JPH048812B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a written data input device.

[Technical background of the invention]

The writing type data input device detects the displacement of the writing axis accompanying the writing motion, identifies the writing character shape (numbers, symbols, etc.), and inputs the data to the information processing section. teeth,
Conventionally, a writing shaft is provided in a pen-shaped gripping case with its tip protruding from the tip of the case, and the writing shaft is placed inside the gripping case during a writing operation by pressing the tip of the writing shaft against a writing surface. There is a structure in which a plurality of piezoelectric elements are arranged to detect the displacement of a writing shaft whose tip side is displaced in a direction opposite to the writing direction.

However, since the conventional writing type data input device described above detects the displacement of the writing shaft by bringing the piezoelectric element into direct contact with the writing shaft,
If an impact is applied to the writing shaft, there is a problem that the impact may destroy the piezoelectric element, and the piezoelectric element only detects when pressure is applied from the writing shaft. Therefore, in order to reliably detect the displacement of the writing shaft in any direction, it is necessary to arrange four to eight piezoelectric elements so as to surround the outer periphery of the writing shaft, making it difficult to assemble the piezoelectric elements. There was also the problem of poor assembly.

For this reason, solutions to the above problem have been studied for some time.

Figure 11 shows a writing type data input device that the applicant is considering as a solution to the above problem.In principle, this writing type data input device can be used as a strain sensor to detect the displacement of the writing shaft. The strain gauge is attached to an elastic member that is in elastic contact with the writing shaft, and the strain gauge is mechanically deformed by the deformation of the elastic member that elastically deforms as the writing shaft is displaced. The displacement of the writing shaft is detected from the amount of electrical change corresponding to the amount of mechanical deformation of the gauge.

To explain this writing type data input device, in FIG. 11, 1 is a pen-shaped cylindrical gripping case, and inside this gripping case 1 is a writing shaft 2 with its tip protruding from the tip of the case 1. It is set in.

This writing shaft 2 is similar to, for example, a ballpoint pen refill (center core of a ballpoint pen), and the writing shaft 2 is shaped like a ballpoint pen when the tip of the writing shaft 2 is pressed against a writing surface (for example, a paper surface). The side is provided so as to be displaced in a direction opposite to the writing direction.

Reference numerals 3 and 3 denote a pair of leaf springs located outside the writing shaft 2 and provided inside the grip case 1. One leaf spring 3 is used to hold the grip case 1 on a writing surface with a predetermined side facing up. On the other hand, the leaf spring 3 is arranged so as to be located directly above the writing shaft 2 when the writing state is held diagonally, and the other leaf spring 3 is arranged so as to be located right next to the writing shaft 2 (here, on the right side) when the writing state is held diagonally. There is.

The base ends of the pair of leaf springs 3, 3 are each fixed in the grip case 1, and the tips thereof are bent toward the writing shaft 2 and brought into elastic contact with the outer periphery of the writing shaft 2.

4x is an X-axis direction strain gauge attached to the outer surface of the leaf spring 3, which is located right next to the writing shaft 2 in the writing state, of the pair of leaf springs 3, 3, and 4y is the other leaf spring, that is, the writing shaft in the writing state. These strain gauges are Y-axis direction strain gauges attached to the outer surface of the leaf spring 3 located directly above the leaf spring 2, and these strain gauges 4x and 4y are
For example, it has a structure in which a silicon semiconductor film b is coated on the outer surface of a flexible substrate a that is bonded to a leaf spring 3.

These strain gauges 4x, 4y generate mechanical deformation (strain deformation) by bending and deforming the leaf springs 3, 3 due to the displacement of the writing shaft 2, and convert the amount of mechanical deformation into the amount of electrical deformation. It has a characteristic as shown in FIG. 12, in which the resistance value increases due to compressive strain, and the resistance value decreases due to compressive strain.

The strain gauges 4x and 4y are connected to a writing character recognition circuit (not shown) provided in the grip case 1 through lead wires 5 and 5, and the strain gauge wires 4x and 4y are The change in resistance value is input to the handwriting shape recognition circuit as a voltage change.

On the other hand, 3a, 3a are the strain gauges 4x, 4
A pair of auxiliary leaf springs are provided to face the leaf springs 3, 3 with the writing shaft 2 in between, and the base ends of the auxiliary leaf springs 3a, 3a are also gripped by the case 1. The tip is bent toward the writing shaft 2 and brought into elastic contact with the outer periphery of the writing shaft 2.

The auxiliary leaf springs 3a, 3a press the writing shaft 2 toward the leaf springs 3, 3 to hold the writing shaft 2 in a neutral state.
a, 3a and the plate springs 3, 3, it is equally pressed from four directions and held at the neutral position.

To explain the operation of this writing-type data input device, this writing-type data input device is similar to writing instruments such as ballpoint pens and fountain pens. This writing-type data input device is used by holding it in a posture tilted toward the front side.
As shown in Figure a, it is used by being held obliquely to the writing surface so that a predetermined side, that is, the side where the Y-axis direction strain gauge 4y is provided, faces upward.

However, when the tip of the writing shaft 2 is pressed against the writing surface while holding the grip case 1 diagonally as described above, the writing shaft 2 is caused by the force of pressing the writing shaft against the writing surface.
The tip side of is displaced in the Y-axis direction shown in Fig. 13a,
Due to this displacement of the writing shaft 2, the leaf spring 3 to which the Y-axis direction strain gauge 4y is attached is pushed by the writing shaft 2 and deflects outward (upwards). When the leaf spring is deflected outward in this way, the Y-axis direction strain gauge 4y attached to the outer surface of the leaf spring 3 generates compressive strain, its resistance value decreases, and the writing axis displacement in the Y-axis direction is reduced. The output voltage shown (hereinafter referred to as Y-axis output) changes from the reference voltage V0 to V1 as shown in the Y-axis column of FIG. 13b.

Hereinafter, the amount of change in the output voltage at the time when the tip of the writing shaft is pressed against the writing surface will be referred to as an initial bias.

In this writing preparation state, that is, in a state where the tip of the writing shaft is simply pressed against the writing surface, the writing shaft 2 does not displace in the lateral direction (X-axis direction).
The axial strain gauge 4x does not undergo strain deformation, so the output voltage V1 indicating the writing axis displacement in the X-axis direction at this time is the same as the reference voltage V0 (V1) as shown in the Y-axis column of FIG. = V0). That is, in this writing preparation state, there is no initial bias in the output indicating the writing axis displacement in the X-axis direction (hereinafter referred to as the X-axis output).

Next, when writing is started from this writing preparation state, writing pressure is applied to the writing shaft 2 by this writing operation, so that the amount of displacement of the writing shaft 2 becomes even larger.

For example, if you input the number "1" by hand, the number "1" is normally written in a diagonal line from the upper right to the lower left, so in this case, the writing axis 2 will be displaced diagonally to the upper right. . Therefore, when writing the number "1", both leaf springs 3, 3 are deflected outward, and as a result, the Y-axis strain gauge 4y is further distorted in the compression direction, and the X-axis Since the directional strain gauge 4x also generates compressive strain, when the number "1" is input by hand, Y-axis and X-axis outputs having waveforms as shown in the upper column of FIG. 13b are obtained. V2 indicates the output voltage during this writing.

Next, we will explain the case where the subtraction symbol "-" is input by hand. Since the subtraction symbol "-" is written almost horizontally from left to right, in this case the writing axis 2 is displaced to the left. . Therefore, when writing the subtraction symbol "-", the strain gauge 4 in the Y-axis direction
y undergoes compressive strain in response to writing pressure, but in the case of the X-axis direction strain gauge 4x, the leaf spring 3 to which it is attached bends inward (to the writing shaft side) following the leftward displacement of the writing shaft 2. Due to the deformation, tensile strain will be generated. Therefore, when the subtraction symbol "-" is input on the writing axis, the waveform Y-axis output and X-axis output as shown in the lower column of Fig. 13b will be obtained. It will be done.

That is, in this writing type data input device, the leaf springs 3, 3 are brought into elastic contact with the writing axis 2 from the X-axis direction and the Y direction, which are orthogonal to each other.
In addition, an X-axis strain gauge 4x and a Y-direction strain gauge 4y are installed, which generate tensile or compressive strain by elastically deforming the leaf springs 3, 3 in the outward and outward directions as the writing shaft 2 is displaced, thereby increasing and decreasing the resistance value. Therefore, the handwritten character shape is recognized by a combination of changes in the X-axis output and Y-axis output due to strain deformation of both strain gauges 4x and 4y.

Therefore, according to this written data input device,
Since the strain gauges 4x and 4y are not in direct contact with the writing shaft 2, there is no fear that the strain gauges 4x and 4y will be destroyed even if an impact is applied to the writing shaft 2, and the writing shaft can be easily fixed with just the two strain gauges 4x and 4y. In order to be able to detect displacement in any direction of the writing axis, it is only necessary to provide the above two strain gauges 4x and 4y as sensors for detecting writing axis displacement. is also easy.

[Problems with background technology]

However, the above written data input device
An X-axis direction strain gauge 4x is provided so as to be positioned directly beside the writing shaft 2 in a writing preparation state in which the grip case 1 is gripped diagonally, so that no initial bias occurs in the X-axis output in the writing preparation state. Therefore, it is possible to write without gripping the gripping case 1 in the correct posture (a posture in which the Y-axis strain gauge 4y is located directly below the writing shaft 2 and the X-axis strain gauge 4x is located directly beside the writing shaft 2). There was a problem in that when inputting characters, it was not possible to correctly recognize the written characters.

To explain an example of this misrecognition of a written character shape, Fig. 14a shows the positions of the strain gauges 4x and 4y when the gripping case 1 is gripped in a position rotated clockwise to some extent from the correct gripping position. At this time, the Y-axis direction strain gauge 4y is placed on the writing axis 2.
The X-axis strain gauge 4x is shifted to the right from the position directly above the writing shaft 2, and the X-axis strain gauge 4x is shifted downward from the position directly beside the writing shaft 2.

When the tip of the writing shaft 2 is pressed against the writing surface in this state, the leaf spring 3 to which the Y-axis strain gauge 4y is attached deforms outward as the writing shaft 2 is displaced in the Y-axis direction. Then, the leaf spring 3 to which the X-axis direction strain gauge 4x is attached is deformed inward. Therefore, at this time, the Y-axis direction strain gauge 4y produces compressive strain, and the Y-axis output becomes the initial bias voltage of voltage value V1 shown in FIG. 14b, and the
The axial strain gauge 4x generates tensile strain, and the X-axis output becomes an initial bias voltage of voltage value V1.

Then, when the number "1" is input by hand, the Y-axis strain gauge 4y undergoes further compressive strain and the Y-axis output becomes V2, and the X-axis strain gauge 4x further undergoes tensile strain and the X-axis output becomes V2.
Therefore, in this case, the X-axis output and Y-axis output have the waveforms shown in the upper column of FIG. 14b.

In other words, the waveform of the X-axis output when gripping case 1 is gripped in a position rotated clockwise to some extent from the correct gripping position and the number "1" is input by hand is as follows:
Grip case 1 in the correct posture and press the number “1”
The waveform has the opposite polarity to the waveform of the X-axis output when ``1'' is inputted in writing, and therefore, even though the number ``1'' is inputted in writing, the written ``1'' is not recognized as another ``1''. (The waveforms of the X-axis output and Y-axis output at this time are as follows: When gripping case 1 is held in the correct posture, the subtraction symbol "-" is displayed.)
Since the waveforms of the X-axis output and Y-axis output are similar to those obtained when ``1'' is input in writing, the written character shape of ``1'' is erroneously recognized as a subtraction symbol ``-''. ). Note that the waveforms of the X-axis output and Y-axis output when the subtraction symbol "-" is entered are as shown in the lower column of Fig. 14b, and this waveform is generated when the gripping case 1 is held in the correct posture. Since the waveforms of the X-axis output and Y-axis output are similar to those obtained when the subtraction symbol "-" is input by hand while gripping the device, there is no need to worry about misrecognition of the subtraction symbol "-".

This also applies when writing is performed while holding the gripping case 1 in a position rotated counterclockwise to some extent from the correct gripping position. In that case, the X-axis output is the waveform in the Since the waveform is an inversion of the above, the written character "-" is mistakenly recognized as the number "1", contrary to the above.

[Purpose of the invention]

This invention was made in view of the above-mentioned circumstances, and its purpose is to
Although the device detects the displacement of the writing shaft using only one strain gauge, there is no need to worry about misrecognizing the writing shape even when the grip case is held in the correct position and rotated in the circumferential direction. The object of the present invention is to provide a writing-type data input device that does not require a manual data input device.

[Summary of the invention]

That is, in the present invention, when a pair of elastic members to which a strain gauge is attached are gripped diagonally with respect to a writing surface in the correct gripping position according to the mark provided on the gripping case to indicate the correct gripping position, By providing a pair of elastic members so that they are shifted by approximately equal angles on both sides of the vertical line passing through the writing axis, the gripping case can be gripped and written in a position rotated in the circumferential direction from the correct gripping position. Even when an input is made, the deformation of both strain gauges due to the displacement direction of the writing axis has the same tendency as the deformation of both strain gauges when the grip case is held in the correct posture and a written input is made. be.

[Embodiments of the invention]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings, taking a handwritten input type small electronic calculator as an example.

The handwritten input type small electronic calculator of this example is as follows:
It is a pen-shaped device with a length of 150 to 200 mm, with the central part to the proximal end serving as the main body of the computer, and the tip end serving as the writing input part.

To explain the configuration of this handwritten input type small electronic calculator, in FIGS. 1 to 5, 10 is a pen-shaped grip case, and this grip case 10 is a case of the main body of the computer (hereinafter referred to as the main body case). )
10a, and a writing input section case (hereinafter referred to as input section case) 10b. The main body case 10a and the input case 10b are both cylindrical, and the main body case 10a has a diameter of 12 to
The thickness is 15mm, and the input case 10b has a diameter of 10mm.
It is said to be ~12mm thick.

The main body case 10a includes a shaft cylinder 1 made of synthetic resin.
1 is covered with a metal outer cylinder 12 except for the tip thereof, and one side of the shaft cylinder 11 is provided with a horizontally long opening 11a along the axial direction of the case, and the metal outer cylinder 12 includes: In correspondence with the opening 11a of the shaft cylinder 11, an opening 12a is provided which is slightly smaller in length and width than the opening 11a.

Reference numeral 13 denotes a flat display panel fitted into the opening 11a of the shaft cylinder 11, and the periphery of the display panel 13 is covered with the peripheral edge of the opening 12a of the metal outer cylinder 12. A display window 14 fitted with a transparent plate 14a is provided at one end of the display panel 13, and a skip (SK) key 15, a subsequence (SB) key 16, and a subsequence (SB) key 16 are provided at the other end.
A clear (C) key 17 is arranged in one line.

Further, a liquid crystal display element 18 is disposed inside the shaft tube 11 so as to face the display window 14, and behind this liquid crystal display element 18, a wiring having a length extending almost the entire length of the display panel 13 is arranged. A substrate 19 is provided. This wiring board 19 has, on its back side, a written character shape recognition circuit that recognizes written character shapes (numbers, symbols, etc.) based on input from a writing type input section, and performs calculation processing based on input data from this recognition circuit. This wiring board 1 is equipped with an LSI chip 20 forming an information processing circuit, a display drive circuit, etc., and other circuit components (not shown).
Reference numeral 9 indicates substrate support portions 21, 21 formed within the shaft cylinder 11.
It is fixed with screws etc.

In FIGS. 3 and 5, reference numeral 22 denotes an interconnector 23 for connecting each terminal of the liquid crystal display element 18 and liquid crystal display element connection terminals (not shown) arranged on the surface of the wiring board 19. is a spacer interposed between the back surface of the liquid crystal display element 18 and the wiring board 19, and the liquid crystal display element 18 is connected to the wiring board 19 and the transparent plate 14a of the display window 14 via the interconnector 22 and spacer 23. is sandwiched between.

Further, in FIG. 3, reference numerals 24 and 24 are fixed contacts formed on the surface of the wiring board 19 in correspondence with the respective keys 15, 16, and 17, and 25 is a fixed contact formed on the fixed contact forming portion of the wiring board 19. This is a rubber sheet made of rubber. This rubber sheet 25 is attached to each key 1 at a portion corresponding to each of the fixed contacts 24, 24.
5, 16, 17, and the inner surface of each bulge is provided with a key 15, 1.
The movable contacts 26, 2 are brought into contact with the fixed contacts 24, 24 due to the deformation of the bulges due to the extrusion operations of 6, 17.
6 is provided, and by these movable contacts 26, 26 and the fixed contacts 24, 24, the key 1
Key switches 5, 16, and 17 are formed to be turned on by pressing operations.

Further, a mode changeover switch 27 that also serves as a power switch is provided within the base end of the shaft cylinder 11. This mode changeover switch 27 is comprised of a rotary switch that is changed over by rotation of a knob 27a, and is connected to the wiring board 19 by a lead wire 28.

29 is a removable cap screwed onto the base end of the shaft cylinder 11, and a mode changeover switch 27
is designed to be operated by removing this cap 29. Sound emitting holes 30, 30 are opened in the end face of this cap 29.
A piezoelectric buzzer 31 is provided inside. This piezoelectric buzzer 31 has a writing character shape identification circuit of the LSI chip 20 based on an input signal from the writing type input section.
This piezoelectric buzzer 31 is driven by a sound signal from the LSI chip 20 every time a written character shape is identified. It is attached within the cap 29 by adhesive. 32a, 32
b is a spring terminal for piezoelectric buzzer connection provided at the base end of the shaft tube 11, one of which is the spring terminal 3;
2a is in contact with the inner electrode surface of the piezoelectric buzzer 31, and the other spring terminal 32b is in contact with the vibration plate 31a of the piezoelectric buzzer 31. Note that each spring terminal 32a, 32b is connected to the wiring board 19 by a lead wire 33.

Further, a battery storage section 34 that is open on one side is formed at the tip of the shaft tube 11 that is not covered with the metal outer tube 12.
Two button-shaped small batteries 35, 35 are housed in the battery compartment 4, stacked in series. This battery 35,3
5 is a negative electrode side battery contact spring 3 made of a coil spring.
6 and a positive electrode side battery contact spring 37 consisting of a plate spring, and a negative electrode side battery contact spring 3
The other end of 6 is fixed to the wiring board 19 and connected to the negative battery connection terminal on the wiring board 19 surface.

On the other hand, the positive electrode side battery contact spring 37 is removably mounted inside the battery storage section 34. This positive electrode side battery contact spring 37 is integrally formed with an extending piece 37a that extends to the open part of the battery storage section 34, and this positive electrode side battery contact spring 37 is attached to the tip of the extending piece 37a. It is connected to the positive battery connection terminal on the wiring board 19 through the connected lead wire 38 .

Reference numeral 39 denotes a cushion material that presses the batteries 35, 35, and this cushion material 39 is integrated with the positive battery contact spring 37 by inserting the extension piece 37a of the positive battery contact spring 37 therethrough. ing.

Further, 40 is a metal battery cover that covers the open part of the battery storage section 34, and this battery cover 4
0 has a cylindrical shape that covers the entire circumference of the tip of the shaft tube 11. The battery cover 40 is slidably and rotatably fitted onto the outer periphery of the barrel 11, and is screwed into a threaded portion formed on the outer periphery of the barrel 11 at its base end.

When replacing the batteries 35, 35, the battery cover 40 can be rotated to attach the shaft cylinder 11.
After unscrewing the battery cover 40, the battery cover 40 is slid toward the writing input section as shown by the chain line in FIG. 3. To replace the batteries 35, 35, slide the battery cover 40 toward the writing input section. Possibly battery compartment 3
4, remove the positive electrode side battery contact spring 37 together with the cushion material 39, take out the batteries 35, 35 from inside the battery storage part 34, and install new batteries 35, 35.
After storing the battery, the cushion material 39 and the positive battery contact spring 37 are attached again, and the battery cover 40 is returned to its original position.

In FIG. 2, reference numeral 41 denotes a clip provided on the outer side of the base end side of the main body case 10a, which also serves as a mark indicating the correct gripping posture of the gripping case 10. It is provided at a position shifted approximately 90 degrees from the position in the circumferential direction of the main body case 10a.

Next, to explain the structure of the writing type input section, the case 10b of this writing type input section has a proximal shaft tube 42 made of synthetic resin, as shown in FIGS. 3 and 4.
A metal outer cylinder 43 whose proximal end is fitted onto the outer periphery of the proximal shaft cylinder 42, and a tapered base member which is fitted to the distal end of the metal outer cylinder 43 and tapers toward the distal end. 44, and inside the metal outer cylinder 43 there is a distal end thereof and a proximal shaft cylinder 42.
Insulating cylinder 4 made of synthetic resin except for the part that fits into
5 are fitted and fixed.

Writing shaft insertion holes 42a and 44a having a slightly larger diameter than the writing shaft 46 are passed through the centers of the proximal shaft tube 42 and the base member 44, respectively. protrudes from the base end of the proximal barrel 42, and is inserted into the writing shaft insertion holes 42a, 44a of the proximal barrel 42 and the cap member 44, with its distal end protruding from the distal end of the cap member 44.

This writing shaft 46 is similar to a ballpoint pen refill (center core of a ballpoint pen) in which a writing tip 46a having a writing ball is attached to the tip of the ink cylinder.In this embodiment, the ink cylinder is used as the writing shaft 46. We use manufactured products.

47 is a sphere having a ventilation hole that is fitted and fixed to the base end of the writing shaft 45; 48 is a cylindrical spherical receiver screwed to the base end surface of the base end side barrel 42;
The spherical body 47 is pressed to the innermost part of the spherical body receiver 48 by the coil spring 49, and the spherical body 47
It is rotatably held inside.

This spherical support 48 supports the base end of the writing shaft 46 via the spherical body 47.
is supported by a spherical receiver 48 so as to be able to tilt in any direction with its base end as a fulcrum.
6a to the writing surface to write down numbers, symbols, etc., the tip side of the cap member 44
It is adapted to be displaced in the direction opposite to the writing direction by the clearance with the writing shaft insertion hole 44a.

The spherical receiver 48 is made of a plate spring, and a sensor is provided on the outer surface of the spherical receiver 48 as shown in FIG. A semiconductor strain gauge 50z similar to the strain gauge shown is fixed with adhesive. This strain gauge 50z prevents mechanical deformation by deforming the spherical receiver 48, which elastically deforms in the axial direction due to the force applied in the axial direction of the writing shaft 46 when the tip (writing tip 46a) of the writing shaft 46 is pressed against the writing surface. The strain gauge 50z converts the amount of mechanical deformation generated into an amount of electrical change, and when tensile strain occurs in the strain gauge 50z, its resistance value increases. This strain gauge 50z in the Z-axis direction is connected to the wiring board 19 of the computer main body by a lead wire 51.

In addition, in the input unit case 10b, three horizontally long leaf springs 5 are provided in the space between the base end side shaft cylinder 42 and the base member 44 along the length direction of the writing shaft.
2, 52, 52a are arranged at equal intervals so as to surround the writing shaft 46, of which two leaf springs 5
2 and 52, a T-axis strain gauge 50t and an S-axis strain gauge 50s are adhesively fixed to the outer surfaces thereof, respectively, as sensors for detecting displacement of the writing shaft 46 in the circumferential direction due to writing motion.

The pair of leaf springs 52, 52 to which the strain gauges 50t, 50s are attached are arranged so that when the gripping case 10 is held diagonally to the writing surface in the correct posture with the predetermined side, that is, the side where the clip 41 is provided facing up, It is provided so as to be located above the center of the writing shaft 46, and the pair of leaf springs 52, 52
When the grip case 10 is gripped in the correct posture as described above, the pair of leaf springs 52, 52 are approximately on both sides of the vertical line passing through the writing shaft 46.
They are arranged so that they are offset by 45 degrees.

In addition, the other leaf spring 52a is connected to the writing shaft 46.
The auxiliary leaf spring 52a serves as an auxiliary leaf spring for holding the writing shaft 46 in a neutral state by pressing the writing shaft 46 toward the pair of leaf springs 52, 52.
It is provided on the side opposite to the pair of leaf springs 52 and 52 with 6 in between, so as to directly face an intermediate position between the pair of leaf springs 52 and 52.

Each of the leaf springs 52, 52, 52a has its base end screwed to the outer periphery of a cylindrical protrusion 42b protruding from the tip of the proximal shaft cylinder 42, so that it can be held in a cantilevered state within the input case 10b. The writing shaft 46 is fixed in place, and is elastically deformed in the radial direction of the writing shaft 46 at the tip side from this fixed part. Further, the tip of each of the leaf springs 52, 52, 52a is bent toward the writing shaft 46 as shown in FIG. As a result, the writing axis 46 is
The writing shaft 46 is maintained in a neutral state, that is, in a state in which the writing shaft 46 is located at the center of the writing shaft insertion holes 42a, 44a of the base-side barrel 42 and the base member 44.

Each of the leaf springs 52, 52, 52a is made of stainless steel with a thickness of approximately 0.5 mm, a width of approximately 4 mm, and a length of the bent portion of approximately 10 mm.
2, 52a has a spring force that causes the tip of the leaf spring to displace about 0.4 mm when 1 kg of writing pressure (pressure that displaces the writing shaft 46 in the circumferential direction) is applied to the writing shaft 46. Although there are individual differences in writing pressure, this writing pressure is about 0.5 to 1.5 kg (usually about 0.7 kg), so the spring force of the leaf springs 52, 52, 52a is selected to the above value. By doing so, even if there are individual differences in writing pressure, the leaf springs 52, 52, 52a can be sufficiently deflected and deformed by the writing pressure. However, the writing pressure
If the weight exceeds 1.5Kg, use leaf springs 52, 52, 52.
Since the amount of deflection of a becomes too large and the leaf spring becomes fatigued due to repeated deflection and deformation, in this embodiment,
The diameter of the writing shaft insertion hole 44a of the base member 44 is set so that when the amount of deflection of the leaf springs 52, 52, 52a exceeds a certain level, the writing shaft 46 hits the base member 44 and is prevented from further deformation. The durability of the leaf springs 52, 52, 52a is ensured by selecting the appropriate length.

The strain gauges 50t and 50s attached to the pair of leaf springs also have a silicon semiconductor film b coated on the outer surface of a flexible substrate a that is bonded to the leaf springs 52 and 52, as shown in FIG. It is considered a semiconductor strain gauge.

These strain gauges 50t, 50s generate mechanical deformation due to the deflection deformation of the leaf springs 52, 52 due to the displacement of the writing shaft 46, and convert this mechanical deformation amount into an electrical change amount.
50s, the electrical resistance value increases due to tensile strain, and the resistance value decreases due to compressive strain.
It has the characteristics shown in Figure 2. These strain gauges 50t, 50s have lead wires 53, 5
3 to the wiring board 19 of the computer main body. The lead wires 53, 53 are guided into the main body case 10a through a lead wire insertion hole (not shown) provided in the proximal shaft tube 42.

Further, the base of the base member 44 extends from the distal end of the metal outer cylinder 43 to the distal end of the insulating inner cylinder 45 and is fitted inside thereof so as to be slidable in the circumferential direction and the axial direction. As shown in FIG. 6, the portion of the cap member 44 that fits into the insulating inner cylinder 45 has a protrusion 54 (see FIG. 3) that projects from a part of the inside of the tip edge of the insulating inner cylinder 45. An inclined groove 55 is formed to slidably engage.

By rotating this base member 44, the base member 44 is moved in the axial direction by the guiding action of the inclined groove 55, and when the small electronic calculator of the writing input type is used, the writing tip at the end of the writing shaft 46 is moved from its tip to the tip of the writing shaft 46. 4
6a is moved to a protruding state, and when the writing input type small electronic calculator is not used, it is moved to the tip side as shown by the chain line in FIG. 3 to protect the writing tip 46a at the tip of the writing shaft 46. ing.

The above-mentioned writing type input section has a strain gauge of 50t, 5
Leaf springs 52, 52 with 0s attached and auxiliary leaf spring 5
The base end of 2a was fixed to the tip of the proximal barrel 42, a writing shaft 46 was inserted into the proximal barrel 42, and a spherical receiver 48 was attached to the base end of the proximal barrel 42. After that, the insulating inner cylinder 45 is fitted and fixed in advance, and the metal outer cylinder 43 with the base member 44 fitted to the distal end thereof is passed through the writing shaft 46 into the base member 44 and fitted to the outside of the proximal shaft cylinder 42, This metal outer cylinder 4
3 is assembled by caulking it to the proximal barrel 42 with its base end protruding from the base end of the proximal barrel 42, and this writing type input unit is The metal outer cylinder 43 is integrated with the computer main body by fitting the base end of the metal outer cylinder 43 into the tip of the shaft cylinder 11 of the main body case 10a and caulking it to the shaft cylinder 11.

The writing input unit detects circumferential displacement of the writing shaft 46 caused by a writing operation performed by bringing the tip of the writing shaft 46 (writing tip 46a) into contact with a writing surface.
It is detected by two strain gauges 50t, 50s in the T-axis direction and the S-axis direction via plate springs 52, 52, and this writing type input section and the computer main body section are connected to each other.
A written data input device is constituted by the written character shape recognition circuit formed in the LSI chip 20.

To explain the operation of the writing type input section, the plate springs 52, 5 to which strain gauges 50t, 50s are attached.
2 and the auxiliary leaf spring 52a, when no external force is acting on the writing shaft 46, the writing shaft 46 is not deformed either inside (on the writing shaft 46 side) or outside with a constant spring force.
It maintains the cutting position where it presses down.

When the tip side of the writing shaft 46 is displaced upward in FIG. 1, the strain gauges 50t, 50s
The leaf springs 52, 52 with which they are attached are both connected to the writing shaft 4.
6 and deflects outward, both strain gauges 50t and 50s generate compressive strain and their resistance values decrease. Further, when the tip side of the writing shaft 46 is displaced downward, the leaf springs 52, 52 follow the displacement of the writing shaft 46 by their spring force and are deflected inward, and both strain gauges 50t, 50s absorb the tensile strain. As a result, its resistance value Ry2 increases.

Furthermore, when the tip side of the writing shaft 46 is displaced to the left in FIG. 1, the T-axis direction strain gauge 50t
The left leaf spring 52 to which the S-axis direction strain gauge 50s is attached is pushed by the writing shaft 46 and deflects outward, and the right leaf spring 52 to which the S-axis direction strain gauge 50s is attached is pressed by the writing shaft 46.
The T-axis strain gauge 50t generates a compressive strain and its resistance value decreases, and the S-axis strain gauge 50s generates a tensile strain and its resistance value decreases. increases.

Further, when the tip side of the writing shaft 46 is displaced to the right, the left leaf spring 52 to which the T-axis strain gauge 50t is attached is deflected inward, and the right leaf spring 52 to which the S-axis strain gauge 50s is attached is outward. At this time, the T-axis strain gauge 50t generates tensile strain and its resistance value increases, and the S-axis strain gauge 50s generates compressive strain and its resistance value decreases.

In addition, at this time, the auxiliary leaf spring 52a is attached to the writing shaft 4.
6 is deflected and deformed inwardly or outwardly.

Next, I will explain the written character shape recognition circuit.
FIG. 8 shows a circuit of the handwritten input type small electronic calculator, and the handwritten character recognition circuit is composed of a data memory section 60, a registered standard pattern section 61, and a recognition calculation section 62.

Further, the T-axis direction strain gauge 50t and the S
The axial strain gauge 50s and the Z-axis strain gauge 50z are fixed resistors 64a and 64, respectively.
b, 64c are connected in series, and the connection points thereof are connected to a T-axis signal output amplifier 63t, an S-axis signal output amplifier 63s, and a Z-axis signal output amplifier 6, respectively.
3z is connected, and each strain gauge 50
t, 50s, and 50z are connected to the low potential _VDD (-3V) side, and fixed resistors 64a, 64b, and 64c are connected to the high potential _VSS (0V) side.

The outputs of the amplifiers 63t, 63s, and 63z are respectively connected to A/D converters 65t, 65s, and
The data is input to the data memory section 60 via the data terminal 65z.

To explain the operation of this handwritten character recognition circuit, this circuit switches the power switch/mode selector switch 27 to the computer mode and turns on the computer power supply circuit 66 when using a handwritten input type small electronic computer.
Turning it ON puts it into operation.

Then, as shown in FIG. 7, hold the grip case 10 with the clip 41 facing up like a general writing instrument, and move it toward you from a state where it is oriented diagonally to the writing surface (for example, a paper surface) P (from a state where it is perpendicular to the writing surface). When the tip of the writing shaft 46 is pressed against the writing surface P while the writing position is held tilted to the side, the spherical receiver 48 expands and deforms due to the pressure in the axial direction applied to the writing shaft 46. The strain gauge 50z generates tensile strain and its resistance value Rz increases.

When the resistance value Rz of the Z-axis direction strain gauge 50z increases in this way, the divided voltage between this strain gauge 50z and the fixed resistor 64c changes, and the signal is output from the Z-axis signal output amplifier 63z toward the high potential V _SS side. A high voltage is output. The output of this amplifier 63z (hereinafter referred to as Z-axis output) is sent to the A/D converter 65z.
is converted into a digital signal and inputted to the data memory section 60.
0 to the CPU (Central Information Processing Unit) 67, and this Z-axis output is sent to the CPU 6.
7, the CPU 67 applies a reset signal to the timer 68 from its reset terminal R to reset the timer 68.

Further, the data memory section 60 outputs the T-axis signal output amplifier 63t and the S-axis signal output amplifier 63 only when the Z-axis output is input thereto.
is adapted to accept the output of s, and therefore,
When no writing pressure is applied in the axial direction of the writing shaft 46 (when the tip of the writing shaft is not pressed against the paper surface), the outputs of the T-axis signal output amplifier 63t and the S-axis signal output amplifier 63s are output from the data memory section 60.
is no longer entered.

Now, the grip case 10 is clipped to the clip 41.
If you hold it in the correct posture by holding it diagonally so that it is directly above you, then in this correct holding posture,
As shown in FIG. 9a, the T-axis strain gauge 5
The leaf spring 52 to which 0t is attached and the leaf spring 52 to which the S-axis direction strain gauge 50s is attached are connected to the writing shaft 4.
The position is shifted by an equal angle (45 degrees) on both sides of the vertical line (Y-axis line) passing through 6.

When the tip of the writing shaft 46 is pressed against the writing surface P with the grip case 10 held in the correct posture in this way, the tip side of the writing shaft 46 pressed obliquely to the writing surface P will move directly upward (Y axial direction), the plate springs 52, 52 to which the strain gauges 50t, 50s are attached are deflected outward to the same extent, and the T-axis strain gauge 50t attached to both plate springs 52, 52 Both the S-axis direction strain gauge 50s generates compressive strain, and their resistance values Rt and Rs decrease.

When the resistance values Rt and Rs of the T-axis strain gauge 50t and the S-axis strain gauge 50s decrease in this way, the partial voltage between the strain gauges 50t and 50s and the fixed resistors 64a and 64b changes, Since the output of the T-axis signal output amplifier 63t (hereinafter referred to as T-axis output) and the output of the S-axis signal output amplifier 63s (hereinafter referred to as S-axis output) are closer to the low potential V _DD side, the T of this T-axis signal output amplifier 63t 9th axis output and S axis output of S axis signal output amplifier 63s.
An initial bias at point V1 shown in Figure b occurs.

If the number "1" is inputted in this state, the writing shaft 46 is further displaced upward from the initial state due to the writing pressure, so when the number "1" is inputted in writing, the T-axis direction strain is generated. Gauge 5
0t and the S-axis direction strain gauge 50s undergo further compressive strain, and their resistance values Rt and Rs further decrease.
Therefore, when writing the number "1", the T-axis output of the T-axis signal output amplifier 63t and the S-axis output of the S-axis signal output amplifier 63s have an output voltage as shown in the upper column of FIG. 9b. The waveform becomes V2.

Note that the number "1" is usually written in a diagonal line from the upper right to the lower left, so the writing axis 46
will be displaced diagonally to the upper right, and therefore,
The S-axis strain gauge 50s is on the right side of the T-axis strain gauge 50t on the left side with respect to the writing axis 46.
Since the compressive strain is slightly large, the amount of change in the output voltage with respect to the initial bias V1 is slightly larger for the S-axis output.

Next, if the subtraction signal "1" is input by hand, the subtraction symbol "1" is written almost horizontally (in the X-axis direction) from left to right. Displace to the left from the state.

When the subtraction symbol "-" is written, the T-axis direction strain gauge 50t on the left side undergoes further compressive strain and its resistance value Rt decreases, so the T-axis output of the T-axis signal output amplifier 63t is set to the initial bias V1.
The output will be even closer to the low potential V _DD side,
Conversely, the resistance value Rs of the S-axis direction strain gauge 50s on the right increases to reduce the degree of compressive strain, and the S-axis output of the S-axis signal output amplifier s is shifted to the high potential V _SS side, contrary to the initial bias V1. The output will be closer to each other.

Therefore, when writing the subtraction symbol "-", the T-axis output of the T-axis signal output amplifier 63t and the S-axis output of the S-axis signal output amplifier 63s are outputs as shown in the lower column of FIG. 9b. The waveform becomes voltage V2.

Next, a case will be described in which a handwritten input is performed without gripping the gripping case 10 correctly as described above.

For example, if the gripping case 10 is gripped from the correct gripping position to a position rotated clockwise to some extent, at this time, the strain gauges 50t, 50s
As shown in FIG. 10a, the plate springs 52, 52 with which the grip case 10 is attached come to a position offset clockwise from the position when the grip case 10 is gripped in the correct posture, but if the grip case 10 is rotated circumferentially. Since the maximum rotation angle of the grip case 10 when gripped is about 25 degrees, the leaf springs 52, 52 are at an angle of 45 degrees with respect to the X axis when the grip case 10 is gripped in the correct posture. does not shift beyond the center of the writing axis 46 to the opposite side.

Therefore, even when gripping case 10 is gripped in a clockwise position from the correct gripping position, when the tip of writing shaft 46 is pressed against the writing surface,
Since both leaf springs 52, 52 deform outward in the same way as when gripping case 10 is gripped in the correct posture, the T-axis output of T-axis signal output amplifier 63t and the S-axis of S-axis signal output amplifier 63s in T-axis direction To the output,
An initial bias at point V1 shown in FIG. 10b will occur.

If the number "1" is inputted in this state, the upward displacement of the writing shaft 46 causes T
The axial strain gauge 50t and the S axial strain gauge 50s are further subjected to compressive strain, and their resistance value Rt,
Rs further decreased, T-axis signal output amplifier 63t
The T-axis output of the S-axis signal output amplifier 63s and the S-axis output of the S-axis signal output amplifier 63s form the waveform of the output voltage V2 as shown in the upper column of FIG. 10b.

In this case, since the strain gauges 50t and 50s are deviated in the above direction, the compression of the strain gauge 50t in the T-axis direction is greater than when the gripping case 10 is held in the correct posture and the number "1" is input by hand. The degree of strain increases slightly, and conversely, the degree of compressive strain of the S-axis direction strain gauge 50s decreases, so the voltage value V of the T-axis output and S-axis output
2 is slightly different from the voltage value when the gripping case 10 is gripped in the correct posture and the number "1" is input by hand. The waveform has the same tendency as the waveform when the number "1" is input by hand.

Next, suppose that the subtraction symbol "-" is input by hand. When the subtraction symbol "-" is written, the T-axis strain gauge 50t on the left is further compressed, and the S-axis strain gauge 50s on the right is conversely strained. Since the degree of compressive strain is reduced, the T-axis signal output amplifier 63
The T-axis output of t and the S-axis output of the S-axis signal output amplifier 63s have waveforms as shown in the lower column of FIG. 10b.

And when inputting this subtraction symbol "-" by hand,
Because the strain gauges 50t and 50s are deviated in the above direction, the compressive strain of the strain gauge 50t in the T-axis direction is Since the degree of tensile strain of the S-axis direction strain gauge 50s becomes slightly larger, the voltage V2 of the T-axis output and the S-axis output is changed by holding the gripping case 10 in the correct posture and subtracting the sign "-".
Although it is slightly different from the voltage value when inputting by hand, the waveforms of the T-axis output and S-axis output have the same tendency as the waveform when holding the gripping case 10 in the correct posture and inputting the subtraction symbol "-" by writing. It becomes a waveform.

This is also the case when the gripping case 10 is gripped in a counterclockwise rotation position opposite to the above and a handwritten input is performed, and in this case, the T-axis direction strain gauge 50
Although the degree of compression and tensile strain of the strain gauges 50s in the t and S axis directions is opposite to that when the gripping case 10 is gripped in the clockwise direction, the strain directions of the strain gauges 50t and 50s do not change. In this case as well, the waveforms of the T-axis output and the S-axis output have the same tendency as the waveforms when the grip case 10 is held in the correct posture and a handwritten input is performed.

That is, in this writing-type data input device, the pair of leaf springs 52, 52 to which the strain gauges 50t and 50s are attached are held diagonally to the writing surface P in the correct posture with the holding case 10 facing up on a predetermined side. Sometimes this pair of leaf springs 52, 52 are used as the writing shaft 4.
Since the grip case 10 is positioned at approximately equal angles on both sides of the vertical line passing through the vertical line 6, even if the grip case 10 is held in a position rotated in the circumferential direction from the correct grip position and a handwritten input is made. , writing axis 4
Both strain gauges 50t, 50 with a displacement of 6
The strain deformation of s has the same tendency as the strain deformation of both strain gauges 50t and 50s when the gripping case 10 is held in the correct posture and a written input is made. Therefore, this writing type data input device Although the displacement of the writing shaft 46 is detected using only the two strain gauges 50t and 50s, even when the gripping case 10 is held in a position rotated in the circumferential direction from the correct position and input is performed, writing is not possible. There is no need to worry about misrecognizing letterforms.

To explain the recognition of this written character shape, the 8th
As shown in the figure, the T-axis signal output amplifier 63t
The T-axis output of the S-axis signal output amplifier 63s and the S-axis output of the S-axis signal output amplifier 63s are converted into digital signals by the A/D converters 65t and 65s and sent to the data memory section 60.
from this data memory section 60 to the recognition calculation section 62.

In addition, the registered standard pattern section 61 has registered standard glyph patterns such as numbers and operation symbols corresponding to the combination of the T-axis output and the S-axis output, and the recognition operation section 62 receives data from the data memory section 60. The input data is compared with the standard glyph pattern from the registered standard pattern section 61, the glyph pattern with the highest correlation is selected, and the glyph pattern number is sent to the CPU.
67.

Further, when writing of one number or symbol is finished and the tip of the writing shaft 46 is released from the writing surface, the Z-axis direction strain gauge 50z returns from the tensile strain state and the Z-axis signal from the Z-axis signal output amplifier 63z is There is no output. When this Z-axis output disappears,
A start signal is sent from the set terminal S of the CPU 67 to the timer 68, and the timer 68 starts counting clock pulses φ.

When the timer 68 counts the preset number of clock pulses and times out, a carry signal is sent from the timer 68 to the C terminal of the CPU 67, and based on this, the CPU 67
A timing pulse is output from the B terminal to the piezoelectric buzzer 31 to drive the piezoelectric buzzer 31 to sound.

The time-up time of the timer 68 is set to be sufficiently longer than the pause time during the writing operation when inputting numbers, symbols, etc. by writing in a plurality of writing operations. That is, for example, the number “5”
is input by two writing operations: writing "5" and writing "-", but if the time-up time of the timer 68 is set as described above,
The piezoelectric buzzer 31 does not operate for a short period of time after writing "5" until starting writing "-",
The alarm will sound an appropriate amount of time after "5" is completely written.

In other words, this piezoelectric buzzer 31 notifies the end of the input every time one number, symbol, etc. is input by hand, and waits until the piezoelectric buzzer 31 notifies the end of the input to proceed with the next number, symbol, etc. If you enter the information by hand, numbers and symbols, etc. that are input in one writing operation, as well as numbers and symbols, etc. that are input in multiple writing operations, will not be confused as input information for one character. can be entered.

On the other hand, the CPU 67 sends numerical information and calculation command information to the calculation memory section 69 based on the glyph pattern number inputted from the recognition calculation section 62, and the numerical information sent to the calculation memory section 69 is Sent to the display section 70 and displayed on the liquid crystal display element 18
Displayed by

Further, the calculation memory unit 69 stores numerical information from the CPU 67 and executes calculations between the calculation number and the operand according to the calculation command information, and the calculation results are sent to the display unit 70 and displayed. be done.

Next, there are the skip (SK) key 15, subsequence (SB) key 16, and clear (C) key 17 provided on the outer surface of the computer main body.
The effect of this will be explained.

The skip key 15 is operated when registering a standard glyph pattern in the registered standard pattern section 61. When the skip key 15 is pressed while the power switch/mode changeover switch 27 is switched to the standard glyph pattern registration mode, the skip key 15 is pressed. Each time you press 15, the display will show 0, 1, 2,...9,
Numbers and operation symbols such as +, -, ×, ÷, =, . . . are sequentially displayed.

For example, when the number "1" is written down with "1" displayed on the display section, the T-axis output and S-axis output of the T-axis signal output amplifier 53t and the S-axis signal output amplifier 53s are transferred from the data memory section 60. The combination of the T-axis output and the S-axis output at this time is sent to the registered standard pattern section 61, and the next time the skip key 15 is pressed, it is registered as a standard character shape pattern of the number "1".

Therefore, by pressing the skip key 15 and writing down numbers and symbols while sequentially displaying them, a written character shape that matches the user's habits can be registered as a standard character shape pattern in the registered standard pattern section 61. I can do it.

The sub-sequence key 16 is pressed when a written character is misrecognized and a different number or symbol is displayed on the display. When this sub-sequence key 16 is pressed, the recognition calculation section 62 The glyph pattern with the next highest correlation after the glyph pattern selected is selected. Each time the subsequence key 16 is pressed, the glyph patterns are selected in descending order of correlation, and the glyph pattern number input from the recognition calculation section 62 to the CPU 67 is input again.

Therefore, even if incorrect input information is input from the CPU 67 to the arithmetic memory unit 69 due to a misrecognition of a written character shape, the subsequence key 16 must be pressed until the same numbers, symbols, etc. as those input by hand are displayed on the display unit. By pressing the button, the information input to the calculation memory section 69 can be corrected.

In addition, the clear key 17 is pressed to clear the previous calculation result or to clear the input when a number or symbol was entered by hand by mistake. All you have to do is press the clear key 17 and then re-enter the numbers, symbols, etc. by hand.

In addition, when a written character shape is misrecognized as described above and a different number or symbol is displayed on the display, the misrecognition can be corrected by canceling the input using the clear key 17 and inputting it again. Correct the misrecognition of the written character by operating the sub-sequence key 16 or by pressing the clear key 17.
It is up to the user to decide whether to cancel the input and re-enter it.

In other words, this handwriting input type small electronic calculator identifies written numbers, operation symbols, etc. by the displacement of the writing shaft 46, and inputs the data to the information processing section to perform calculations. When you write down symbols, etc., calculations are automatically performed and the calculation results are displayed.

As described above, this handwriting input type small electronic calculator has a base end held on the outside of the writing shaft 46, and a case 1
A pair of leaf springs 52, 52 are provided which are fixed in the inside of the writing shaft 46 and come into elastic contact with the outer periphery of the writing shaft 46 at their tips. When gripped diagonally, the writing shaft 46 is provided so as to be displaced by approximately equal angles on both sides of the vertical line passing through the writing shaft 46, and the pair of leaf springs 52, Strain gauges 50t, 5 which generate mechanical deformation due to elastic deformation of the leaf springs 52, 52 and convert this mechanical deformation amount into an electrical change amount.
0s, and further press the writing shaft 46 on the side facing the pair of leaf springs 52, 52 across the writing shaft 46 to bring the writing shaft 46 into a neutral state. Auxiliary leaf spring 52 to hold
This is a configuration in which a is provided.

In this handwriting input type small electronic calculator, a strain gauge 5 is used to detect the displacement of the writing shaft 46.
A leaf spring 5 with 0t and 50s in elastic contact with the writing shaft 46
2,52, this strain gauge 50t,
Since the strain gauges 50s are prevented from coming into direct contact with the writing shaft 46, even if an impact is applied to the writing shaft 46, the strain gauges 50t and 50s will not be destroyed by this impact, and the displacement of the writing shaft 46 cannot be detected. can be carried out using only the two strain gauges 50t, 50s, and therefore only the two strain gauges 50t, 50s need to be provided as sensors for detecting the displacement of the writing shaft 46.
Incorporation of 0s is also easy.

Moreover, in this handwritten input type small electronic calculator, the pair of leaf springs 52, 52 to which the strain gauges 50t, 50s are attached are provided at the positions described above, so that the gripping case 10 can be moved in the circumferential direction from the correct gripping posture. Even when writing is input while gripping the gripping case 10 in the correct posture, the deformation of both strain gauges 50t and 50s due to the displacement of the writing shaft 46 is the same as when the gripping case 10 is gripped in the correct posture and writing is input. The deformation has the same tendency as the deformation of 50t and 50s, so the two strain gauges 50t and 50s deform.
Although the displacement of the writing shaft 46 is detected in only 50 seconds, there is no need to worry about misrecognizing the written character shape even when the grip case 10 is gripped in a position rotated in the circumferential direction from the correct gripping position and a handwritten input is performed. do not have.

In addition, in the above embodiment, the strain gauge 50t,
A mark (clip 41 in the above embodiment) indicating the correct gripping posture is provided on the gripping case 10 with the leaf springs 52, 52 to which the 50s are attached.
Accordingly, when the grip is held diagonally to the writing surface in the correct gripping posture, the angle is 45 with respect to the vertical line passing through the writing axis 46.
The angle of the leaf springs 52, 52 with respect to the vertical line is
It may be within the range of about 30 to 60 degrees, and the plate spring 5 to which the strain gauges 50t and 50s are attached
2, 52 is a writing shaft 46 when the grip case 10 is gripped diagonally with respect to the writing surface with a predetermined side up.
It may be provided so that it is located below the center. Further, in the above embodiment, the auxiliary leaf spring 52a is one piece, but this auxiliary leaf spring 52a is attached to the writing shaft 4.
They may be provided at two locations so as to directly face a pair of leaf springs 52, 52 to which strain gauges 50t, 50s are attached, respectively, with the strain gauges 50t, 50s sandwiched therebetween.

In addition, in the above embodiment, the strain gauge 50t,
50s is attached to the outer surface of the leaf springs 52, 52;
In addition, the strain gauges 50t and 50s are not limited to semiconductor strain gauges, and strain gauges using metal foil or the like may be used.

Furthermore, in the above embodiment, the strain gauge 50
Elastic member and writing shaft 46 for attaching t, 50s
Although a leaf spring is used as an auxiliary elastic member to return the pen to the neutral state, these elastic members may be made of an elastic resin plate such as polycarbonate, and the writing shaft 46 is limited to a ballpoint pen refill. Alternatively, it may be a simple shaft rod.

Further, in the above embodiment, the Z-axis strain gauge 50z is provided to detect when axial writing pressure is applied to the writing shaft 46, but this Z-axis strain gauge 50z may not be provided. .

Further, in the above embodiment, the writing shaft 46 is supported at its base end so that the tip side can tilt in any direction, but if the writing shaft 46 is made flexible, the base end of the writing shaft 46 may be fixed within the gripping case 10.

Although the above embodiment has been explained by taking as an example a written data input device incorporated in a small electronic calculator with written input, the present invention is also applicable to a data input device that is connected to a personal computer, for example, which is equipped with only a written input section. It can also be applied to a writing type data input device for inputting data to a personal computer.

〔Effect of the invention〕

According to this invention, when the pair of elastic members to which the strain gauges are attached are held diagonally to the writing surface in the correct holding position according to the mark provided on the holding case to indicate the correct holding position, writing is possible. The grip case is positioned at approximately equal angles on both sides of the vertical line passing through the axis, so even if you grip the grip case in a circumferentially rotated position from the correct grip position and perform writing input. The deformation of both strain gauges due to the displacement of the writing axis has the same tendency as the deformation of both strain gauges when the grip case is held in the correct posture and a written input is made.
Therefore, even though the displacement of the writing shaft 46 is detected using only two strain gauges, even when the grip case is held in a position rotated in the circumferential direction from the correct gripping position and a handwritten input is performed, the shape of the writing character remains unchanged. There is no need to worry about misrecognizing it.

[Brief explanation of drawings]

1 to 10 show an embodiment of the present invention, in which FIG. 1 is a perspective view of a displacement detection section of a writing shaft, FIG. 2 is an external perspective view of a small electronic calculator with writing input, Figure 3 is an enlarged cross-sectional view taken along the line A-A in Figure 2, Figures 4 and 5 are enlarged cross-sectional views taken along the lines B-B and C-C in Figure 3, and Figure 6 is the tip of the case. An enlarged perspective view of the mouthpiece member, Fig. 7 is a usage state diagram of the handwritten input type small electronic calculator, Fig. 8 is a circuit diagram of the handwritten input type small electronic calculator, and Fig. 9 is a grip case held in the correct posture. Output waveform diagram when inputting the number “1” and the subtraction symbol “-” by hand,
FIG. 10 is an output waveform diagram when the numeral "1" and the subtraction symbol "-" are input by hand while gripping the gripping case in a position rotated in the circumferential direction from the correct gripping position. FIG. 11 is a perspective view of a writing shaft displacement detection section of a writing data input device that the applicant had considered before this invention, FIG. 12 is a resistance change characteristic diagram of a strain gauge, and FIG. Figure 14 is an output waveform diagram when the numeral "1" and the subtraction symbol "-" are input by hand with the grip case held in the correct posture using the writing data input device shown in Figure 11. FIG. 7 is an output waveform diagram when the number "1" and the subtraction symbol "-" are input by hand while gripping the gripping case in a position rotated in the circumferential direction from the correct gripping position. 10... Gripping case, 46... Writing shaft, 50
t, 50s...strain gauge, 52...plate spring,
52a...Auxiliary leaf spring.

Claims (1)

[Claims] 1. A writing shaft with its tip protruding inside the grip case, whose tip side is displaced in the opposite direction to the writing direction as a writing operation is performed by pressing the tip against a writing surface, and the displacement of this writing shaft is detected. In the writing type data input device, the writing type data input device is equipped with a means for recognizing a written character shape and inputting the data to an information processing unit, the base end of which is fixed in a gripping case on the outside of the writing shaft, and the tip of the writing shaft of the writing shaft. A pair of elastic members are provided that come into elastic contact with the outer periphery, and the pair of elastic members are
When the gripping case is gripped obliquely to the writing surface in the correct gripping position according to the mark provided on the gripping case to indicate the correct gripping position, the gripping case is held at approximately the same angle on both sides of the vertical line passing through the writing axis. Strain gauges are provided at shifted positions, and each of the pair of elastic members causes mechanical deformation by elastic deformation of the elastic member due to displacement of the writing shaft, and converts the amount of mechanical deformation into an amount of electrical change. and further includes at least one auxiliary elastic member on a side of the writing shaft opposite to the pair of elastic members that presses the writing shaft toward the pair of elastic members to hold the writing shaft in a neutral state. A written data input device characterized by being provided with.