JPH03187775A - Printer - Google Patents

Abstract

PURPOSE:To make the printing center of a ribbon correctly correspond to a printing head thereby to prevent the deterioration of printing quality by adding driving pulses by an average of the number of inputs from the start to shut off the light to a pulse motor when the number of the driving pulses reaches the number of the inputs which is corresponding to an optional printing ribbon cassette. CONSTITUTION:Supposing that a cassette bed 7 is found at a first rise position P1 from the number of inputs related to each of printing ribbon cassettes 25A-25C stored in a memory 37 when shutting of the light is started and fin ished, and from the average value of the numbers of the inputs, for instance, in order to position the ribbon cassette 25A to confront to the printing position, the average value Aav related to the ribbon cassette 25A is read from the memory 37, and a pulse motor 33 is driven with the driving pulses of the number of inputs corresponding to the average value Aav. Accordingly, the cassette bed 7 is raised or descended via a rotary cam mechanism 26, and the printing center of a ribbon 25a of the ribbon cassette 25A is set to confront to the print ing head. As a result, the printing quality is improved.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention comprises a pulse motor whose rotation amount is regulated according to the number of drive pulses input, and a plurality of printing ribbon cassettes stacked one above the other. and a cassette stand that sets a printing ribbon cassette at a printing position by being raised and lowered in the vertical direction, and an elevating mechanism that is linked to the pulse motor and that moves the cassette stand up and down a distance corresponding to the amount of rotation of the pulse motor. Regarding a printer equipped with.

(Prior Art) As a printer with the above configuration, there is a multicolor printer in which a plurality of printing ribbon cassettes of different hues are stacked and mounted on a cassette stand.

Regarding this multicolor printer, the applicant
Applications with contents as shown in Figures 3 to 8 by date (
This is called a "conventional application." ) is proposed.

The contents of this conventional application will be explained below.

FIG. 3 is a perspective view showing the overall external appearance of the main parts of a conventional multicolor printer, FIG. 4 is a perspective view showing the structure of the carriage section, and FIG. 5 is a schematic diagram of the carriage section. FIG.

In these figures, the symbol ! is the main frame, 2 is the carriage base, 3 is the motor for horizontal movement of the carriage base,
Reference numeral 4 designates a feed roller that sends the printing paper upward, 5 a motor for driving the feed roller, 6 a thermal head as a print head, 7 a cassette stand, 8 a ribbon winding reel, and 9 a platen.

As shown in FIGS. 4 and 5, the carriage base 2 has a guide shaft IO supported horizontally on the main frame l.
A roller is attached to a guide plate 11 that is supported so as to be movable laterally along the main frame l and is fixed to the main frame l. The carriage base 2 is supported via a timing belt 2 and connected to a timing belt 13 driven by a motor 3, so that the carriage base 2 is reciprocated with a predetermined stroke by the forward and reverse rotation of the motor 3. Note that the ribbon take-up reel 8 is connected to a gear 15 provided at the bottom of the carriage base 2.
When the carriage base 2 moves forward, the gear 15 meshes with a rack 16 provided parallel to the guide plate 1-11 and is driven to rotate, and accordingly, the ribbon take-up reel 8 is wound. It is designed to be driven.

The cassette stand 7 is attached above the carriage base 2 via two pairs of left and right X-shaped sinks 17 and 18.

X type sunk + 7.18 The rear end of each is connected to the pin 1 on the rear side of the carriage base 2 and cassette stand 7.
9.20, and the front end is engaged and connected through longitudinal holes 2I, 22 and guide pins 23.24. The cassette table 7 is configured to move up and down in parallel. Three printing ribbon cassettes 25A, 25B, and 25G can be stacked and mounted on this cassette stand 7, and each printing thermal head 6 and printing ribbon cassette is irradiated with light and receives light. A photosensor 32 as a means is inserted.

6(a) to 6(C) show the elevating and lowering drive structure of the cassette table 7 and its operating procedure. Below the cassette table 7, a rotary cam mechanism 26 that is driven to rotate in forward and reverse directions is provided as an elevating mechanism. This rotary cam mechanism 26 has a first cam 28 with a small diameter outer circumferential surface fixed to a drive mechanism 27 capable of forward and reverse rotation, and a second cam 29 with a large diameter and an arcuate outer circumferential surface fitted loosely therein. In addition, the pin 31 of the second cam 29 is inserted into the arc-shaped elongated hole 30 formed in the first cam 28 .

In the normal state, the first cam 28 and the second cam 29 are in a position where they are each rotated to the left as much as possible, as shown in FIG. It is in the lowest position. In this case, the drive claw 8a of the take-up reel 8 is connected to the uppermost printing ribbon cassette 25A.
Only this printing ribbon cassette 25A is set in a state in which the ribbon can be wound, that is, in a state in which printing is possible. When the drive shaft 27 rotates 90 degrees clockwise from the state shown in FIG. 6(a), the cassette stand 7 is raised by a certain amount on the outer circumferential arc surface of the first cam 28, as shown in FIG. 6(b). , at this time, the middle row.

The printing ribbon cassette 25B is set in a printable position. Further, during this 90 degree rotation, the second cam 29 is maintained at its original position by the elongated hole 3o and the pin 31.

When the drive shaft 27 further rotates 90 degrees clockwise from the state shown in FIG. 6(b), the second cam 29 changes from the solid line to the two-dot chain line due to the engagement between one end of the elongated hole 30 and the pin 3. It starts rotating integrally with the first cam 28. In this case, until the second cam 29 comes into contact with the cassette stand 7, the outer circumferential arc surface of the first cam 28 acts, so that the cassette stand 7 is not displaced. Then, as the second cam 29 comes into contact with the cassette stand 7 and rotates, the cassette stand 7 is greatly pushed up and raised as shown in FIG. 6(C). The ribbon cassette 25C reaches the printable position. Note that by rotating the drive shaft 27 counterclockwise, the cassette table 7 is rotated by the reverse operation of the above operation.
It is lowered step by step.

Mechanistically, the double photosensor 32 has a structure explained with reference to FIGS. 7 and 8. That is, the photosensor 32 serving as the irradiation/light receiving means is the seventh
As shown in FIG. 8 and FIG. 8, a light emitting element 32a consisting of a light emitting diode facing the ribbon side and a transmitted light receiving element 32b consisting of a light receiving diode are assembled into an appropriate assembly member, and from the light emitting element 32a. When the irradiation light is rotated, it passes through the ribbon 25a of the uppermost printing ribbon cassette 25A in the printable position and is reflected by the light reflection plate 36 attached to the back surface of the printing paper guide 14. The reflected light is received by the transmitted light receiving element 32b.

(Problems to be Solved by the Invention) In such a multicolor printer, blank printing can be prevented by detecting the end of the ribbon using the photosensor 32 serving as the irradiation/light receiving means. Such problems are pointed out.

That is, the drive mechanism 27 for the first cam 28 is controlled by a pulse motor (not shown). This pulse motor has a rotation amount corresponding to the number of drive pulses input to it, and when the first cam 28 is in the state 'etiN of FIGS. 6(a) and 6(b), it is in the state shown in FIG. 6(C). A hit is provided that hits the first cam 28 when driven as shown in FIG. The behavior of the first cam 28 was controlled by determining the number of drive pulses for each of the states shown in FIG.

However, in such control, each cam 28°29,
Cassette stand 7, printing ribbon cassette 25A, 25B
, 25G, and errors in the operation of the pulse motor, a portion of the printing center of each ribbon of each printing ribbon cassette 25A, 25B, and 25C does not correspond accurately to the print head 6, resulting in extreme In such cases, the print head 6 does not hit the ribbon, or even if it hits the ribbon, it is deviated from a part of the print center, resulting in a drop in print quality, resulting in deterioration in print quality.

Therefore, in the present invention, when an arbitrary printing ribbon cassette is set in the printing position by raising and lowering the cassette stand in the vertical direction, a portion of the printing center of the ribbon in that set accurately corresponds to the printing head. The aim is to eliminate deterioration in print quality.

(Means for Solving the Problems) In the printer of the present invention, a pulse motor whose rotation amount corresponds to the number of input drive pulses and a plurality of ribbon cassettes for printing can be stacked vertically and mounted. A printer equipped with a cassette stand that moves up and down in order to set a printing ribbon cassette at a printing position, and an elevating mechanism that moves up and down the cassette stand in conjunction with the rotation of the pulse motor in accordance with the amount of rotation. consists of a light emitting part and a light receiving part placed in a position where the light from the emitting part can be received, and the light on the light path between the emitting part and the light receiving part is set at the printing position. Based on the irradiation/light receiving means that is shielded from light by the ribbon of a certain printing ribbon cassette, the drive pulse data from the control means described later, and the output of the irradiation/light receiving means, the first
The number of drive pulses input to the pulse motor from the vertical position to the second vertical position where light on the optical path is blocked (shading start input number), and the number of drive pulses input to the pulse motor from the first vertical position to the second vertical position where the light on the optical path is blocked; Number of drive pulses input to the pulse motor until the third lifting position where the state ends (number of inputs to end shading)
an input number measuring means for measuring each of the printing ribbon cassettes; an average value calculation means for calculating the average value of the two-person dispersion for each printing ribbon cassette, and storing each of the average values. Memo i: When outputting drive pulse data to the input number measuring means and setting an arbitrary printing ribbon cassette at the printing position, the above-mentioned information stored in the memory corresponding to the arbitrary printing ribbon cassette is The present invention is characterized by comprising a control means for outputting an input number of drive pulses to the pulse motor corresponding to the average value.

(Function) When the cassette stand is raised and lowered by the lifting mechanism from the first lifting position to the second lifting position, the ribbon of the printing ribbon cassette mounted on the cassette stand moves the light on the light path in the irradiation/light receiving means. is shielded from light, and when it is lifted and lowered from the first lifting position to the third lifting position, the shaded state disappears. The input number measuring means measures the number of inputs of drive pulses given to the pulse motor from the first lifting position to the second lifting position (shading start input number), and the number of inputs of drive pulses given to the pulse motor from the first lifting position to the third lifting position.
The number of drive pulse inputs given to the pulse motor up to the lifting/lowering position (the number of inputs at the end of light shielding) is measured for each printing ribbon cassette.

The calculation means calculates the average value of the two-person variance, and stores the average value in the memory.

The control means reads an average value from the memory corresponding to the arbitrary printing ribbon cassette when raising or lowering the cassette stand to set an arbitrary printing ribbon cassette at a printing position from among the plurality of printing ribbon cassettes. At the same time, the number of input drive pulses corresponding to the average value is output to the pulse motor.

That is, in the present invention, for example, when the number of drive pulses reaches the number of light shielding start inputs corresponding to the arbitrary printing ribbon cassette, an additional number of drive pulses equal to the average value is added to the pulse motor, resulting in The cassette stand can be raised and lowered by the lifting mechanism so that a part of the printing center of the ribbon of any printing ribbon cassette faces the print head.

(Example) Hereinafter, an example of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a circuit diagram of the main parts of a printer according to an embodiment of the present invention, and FIG. Figure (b
) is a diagram showing the light passing path 34 of the photosensor 32 at a high level when the light is blocked and when the light is released from the light at a low level. FIG. It is a figure which shows the height position change of the ribbon of a printing ribbon cassette.

The printer of the present invention is applicable to the multicolor printer shown in FIGS. 3 to 8, and has the same structure as the multicolor printer. Note that the structure of this multicolor printer is shown in those figures, so a detailed explanation will be omitted here.

The present invention has the following configuration in addition to the configurations shown in FIGS. 3 to 8 above.

As shown in FIG. 1, a rotating cam mechanism 26 serving as an elevating mechanism is driven by a pulse motor 33 whose rotation amount is defined in accordance with the number of drive pulses input. A light passage 3 is provided between the light emitting element 32a as a light emitting part of the photosensor 32 and the transmitted light receiving element 32b as a light receiving part.
4 is formed, and the light on this light passage 34 passes through the second
The ribbon 25a of each printing ribbon cassette is
, 25b and 25c.

The input number measuring means 35 is supplied with data regarding the number of drive pulses input to the pulse motor 33 from the control means 36 and with the light reception output from the photosensor 32.

The input number measuring means 35 is configured such that, for example, the cassette table 7 moves from the first lifting position PI (■ in FIG. 2(a)) to the second position where the light passage 34 is shielded from light by the ribbon 25a of the printing ribbon cassette 25A. When the elevator is moved up and down to lifting position P2 [between ■ and ■ in Figure 2 (a)], the number of drive pulse inputs from the first lifting position PI to the second lifting position P2 is defined as the number of inputs at which light shielding starts. al, the third elevating position P3 (■ and ■ in Fig. 2 (a)) where the light shielding is released from the first elevating position PI
When the light emitting device is lifted up and down to a position between the first and second lifting positions pt and 3, the number of input drive pulses from the first lifting position pt to the third lifting position P3 is counted as the number of inputs a2 at the end of shading. The input number measuring means 35 is connected to another printing ribbon cassette 25 in the same manner as described above.
Between the first elevating position PI and the second elevating position P2' of the cassette table 7 regarding B [between ■ and ■ in FIG. 2(a)]
between the first vertical position 1iIP1 and the third vertical position P3', where the number of drive pulse inputs is defined as the number b1 of light shielding start inputs.
The number of drive pulse inputs between ■ and ■ in FIG. The number of drive pulse inputs between position P2'' [between ■ and ■ in Figure 2 (a)] is set as the number of light shielding start inputs CI, and the first vertical position PK and the third vertical position P3'' are Between [
The number of input drive pulses between ■ and ■ in FIG. 2(a) is measured as the number of inputs at the end of light shielding C2.

In this case, the input number measuring means 35 determines whether the cassette table 7 is at the second vertical position P2, P2'P2'' and the third vertical position P3, P3' based on the state of the light reception output from the photosensor 32.
, P3'' and measure the number of inputs.

To explain this with reference to FIG. 2, first, the cassette stand 7 is raised and lowered sequentially from ■ to ■ in FIG. 2(a) at time to, and the ribbon height of each printing ribbon cassette is becomes higher as shown in Figure 2 (C). Then, at time 11, when the cassette table 7 reaches the second elevating position P2 and the optical path 34 is blocked by the ribbon 25a of the printing ribbon cassette 25A, the photo sensor 32 for the input number measuring means 35 is The received light output changes from low level to high level at time [l] in FIG. 2(b).

The input number measuring means 35 detects the photo sensor 3 due to the above-mentioned light shielding.
2, when there is a change in the received light output, the number of driving pulse inputs from the first lifting position pt to the second lifting position P2 is determined as the light shielding start input from the driving pulse input number data given from the control means 36. It is measured as number 81. Further, at time t2, when the cassette table 7 reaches the third elevating position P3 and the light passing path 34 is unblocked by the ribbon 25a of the printing ribbon cassette 25A, the input number measuring means 3
The light receiving output of the photosensor 32 for 5 is shown in Fig. 2(b).
Since the level changes from the high level to the low level at the time [2, the input number measuring means 35 calculates the number of drive pulses input from the control means 36 based on the data on the number of drive pulses input at that time. The number of drive pulse inputs from the vertical position P1 to the third vertical position 1) 3 is measured as the number of light shielding end inputs a2. In this way, as the cassette stand 7 moves up and down, the input number measuring means 35 calculates the time t3. Let the number of shading start inputs at t5 be bl and cl, and the number of shading end inputs at times t4 and t6 be b2. Measure as c2.

The memory 37 stores the number of shading start inputs a l, b 1 . c l and number of shading end inputs a 2. b2. c 2.

The average value calculating means 38 calculates the input number al related to the printing ribbon cassette 25A stored in the memory 37.

Average value of a2 Aa v (=(a l+a 2) /2
), the number of inputs bt regarding the printing ribbon cassette 25B
.

Average value of b2 Bav, printing ribbon cassette 25C
The average value Cav of the input numbers cl and c2 with respect to the input values cl and c2 are respectively calculated. The average values Aav, Bav, and Cav are also stored in the memory 37, respectively.

The control means 36 controls the operations of the input number measuring means 35, the memory 37, and the calculating means 38, and each printing ribbon cassette 25 stored in the memory 37
Based on the number of light shielding start/end inputs for each of A, 25 B, and 25 C and their average value, the cassette table 7 is at the first vertical position P! For example, if the printing ribbon cassette 25A is to face the printing position when the memory 3
7, the average value AaV regarding the printing ribbon cassette 25A is read out, and the pulse motor "33 is driven with the input number of drive pulses corresponding to the average value Aav."

As a result, the cassette stand 7 is raised and lowered via the rotary cam mechanism 26, and the ribbon 25a of the printing ribbon cassette 25A is moved up and down.
A part of the print center of the printer is set so as to face the print head [state shown by ■ in FIG. 2(a)]. Another printing ribbon cassette 25B.

Similarly for 25C, each ribbon 25b,
A part of the print center of the print head 25c is set so as to face the print head [states shown by ■ and ■ in FIG. 2(a)].

Further, for example, when a part of the printing center of the printing ribbon cassette 25G to the printing ribbon cassette 25A is made to face the printing head, the control means 36 stores the average value Ca v of both printing ribbon cassettes 25A and 25G from the memory 37. , Aav are read respectively, and the difference in the number of drive pulse inputs between the read average values Cav −
After calculating Aa v, the rotation direction of the pulse motor 33 is reversed to calculate the difference in the number of inputs Ca v -A.
A number of drive pulses corresponding to av are given to the pulse motor 33. As a result, the cassette table 7 is lowered from ■ to ■ in FIG. 2(a) via the rotating cam mechanism 26.

(Effects of the Invention) As is clear from the above explanation, according to the present invention,
Even if there are variations in the dimensional tolerances of the cassette stand, its lifting mechanism, assembly of printing ribbon cassettes, or errors in the operation of the pulse motor, printing will occur at a portion of the printing center of each ribbon in each printing ribbon cassette. Since the head can be aligned accurately, the print head will not hit the ribbon, or even if it does hit the ribbon, it will not deviate from a part of the print center, resulting in improved print quality. can.

[Brief explanation of drawings]

Fig. 1 is a circuit diagram of the main parts of a printer according to an embodiment of the present invention, Fig. 2 is a diagram for explaining the operation of the embodiment, and Fig. 2(a) shows how the cassette table moves up and down. Figure 2 (
b) shows the light reception output of the photosensor, and FIG. 2(C) is a diagram showing the height of the ribbon of the printing ribbon cassette mounted on the cassette stand. Figures 3 to 8 show a multicolor printer, Figure 3 is an external perspective view showing its main parts, Figure 4 is a perspective view of the carriage shown in Figure 3, and Figure 5 is the same. 6(a), 6(b) and 6(c) are schematic side views showing the sequential upward movement of the cassette table, FIG. 7 is a plan view of the printing ribbon cassette loading section, and FIG. The figure is a partially cutaway side view showing the configuration of the photosensor. 25A~25C...Printing ribbon cassette, 25a~
25c... Ribbon, 26... Rotating cam mechanism (elevating and lowering)
mechanism), 32... photosensor (irradiation/light receiving means),
33... Pulse monitor, 34... Light passage path, 35...
...Input number measuring means, 36...Control means, 37...
Memory, 38...mean value calculation means.

Claims (1)

[Claims] (1) A pulse motor whose rotation amount corresponds to the number of input drive pulses and multiple printing ribbon cassettes can be stacked vertically and vertically to set the installed printing ribbon cassettes at the printing position. A printer equipped with a cassette stand that is raised and lowered in a direction, and an elevating mechanism that moves up and down the cassette stand in conjunction with the rotation of the pulse motor and according to the amount of rotation, the printer comprising: a light irradiation unit; The irradiation system consists of a light receiving section placed in a position where light can be received, and the light on the light path between the irradiating section and the light receiving section is blocked by the ribbon of the printing ribbon cassette set at the printing position.
a second elevating position where light on the light path is blocked from the first elevating position of the cassette table based on drive pulse data from the control means described later and the output of the irradiation/light receiving means; The number of drive pulses input to the pulse motor (shading start input number), and the number of drive pulses input to the pulse motor from the first lifting position to the third lifting position where the shading state ends. an input number measuring means for measuring the number of inputs (the number of inputs at the end of shading) for each printing ribbon cassette; and an average value calculation means for calculating the average value of both the input numbers for each printing ribbon cassette. a memory for storing each of the average values; and a memory for outputting drive pulse data to the input number measuring means, and when setting an arbitrary printing ribbon cassette at a printing position, the above-mentioned data is stored in a memory corresponding to the arbitrary printing ribbon cassette. A printer comprising: control means for outputting an input number of drive pulses to the pulse motor corresponding to the average value stored in a memory.