JPH0156914B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to a printing device that performs printing using a petal-shaped type wheel.

[Objective] The object of the present invention is to enable a petal-shaped type wheel to be easily attached to the main body of a printing device, and to easily attach and detach the attached type wheel to the rotating shaft of the type selection motor and to rotate both of them. An object of the present invention is to provide a new printing device that can easily and reliably determine relative positions in directions.

[Example] An example embodying the present invention will be described below with reference to the drawings.

FIG. 1 is a sectional side view of the main part of a printing device embodying the present invention, in which a support stand (not shown) supported so as to be able to move step by step parallel to the printing surface of the platen 1 is shown. , a type selection pulse motor 2 is supported so as to be able to reciprocate in a direction perpendicular to the printing surface. This reciprocating movement of the pulse motor 2 is performed based on manual operation of a control lever (not shown). A drive member 4 is fitted and fixed to the tip of a motor shaft 3 of the pulse motor 2. Figures 1 and 2
As shown in the figure, at the tip of the drive member 4, there is a shaft portion 6 having a head 5 with a substantially hexagonal cross section, and a flange 8 having a notch-shaped engagement portion 7 at one location on the peripheral edge.
are integrally formed. The drive member 4 and the motor shaft 3 constitute a rotating shaft driven by the pulse motor 2.

A fixing plate 9 (only the upper part is shown) is fixed to the support base, and a cassette holder 11 is tiltably supported by a shaft 10 on a protrusion 9a provided at the lower part of the fixing plate 9. The cassette holder 11 has a front wall 12 on the platen 1 side, a rear wall 13 of the pulse motor 2 (in this embodiment, the platen 1 side is the front part) and a side wall 1.
4 and a lower wall 15, the rear wall 13 has a bent hooking portion 16 that can be engaged with the hooking portion 9b formed on the upper part of the fixing plate 9, and the flange 8 is connected to the cassette holder 11. Through hole 1 for entering and exiting
7 is provided. Further, at a position approximately at the same height as the head 5 of the driving member 4, a pair of latching protrusions 18 as a non-rotating portion are provided at the upper end of the front wall 12.
(also shown in FIGS. 5A to 5C) are provided protrudingly at intervals of 180 degrees. A tension spring 19 is provided to bias the cassette holder 11 toward the fixing plate 9.

As shown in FIGS. 4A and 4B, when the pulse motor 2 is at the rear position, the cassette holder 11 is placed in a position tilted rearward due to the biasing force of the tension spring 19, and as shown in FIGS. As shown in , after the pulse motor 2 moves forward based on manual operation of the operating lever in one direction, it comes into contact with a pressing member (not shown) linked to the operating lever and is placed in an upright position. There is. Further, based on the manual operation of the operating lever in the opposite direction to the above-described operation of the operating lever, the cassette holder 11 is moved in the reverse order to the above-mentioned state, and becomes the state shown in FIGS. 4A and 4B.

The type wheel cassette 20 stored in the cassette holder 11 has a bottom plate 2 having a substantially circular storage recess 21, as shown in FIGS. 3 and 5A.
2 and an upper lid 23 that covers the lower half of the storage recess 21.
It is composed of. An operating recess 22a for pinching this type wheel cassette 20 is provided at the upper edge of the bottom plate 22, and an entry opening is provided at the center of the upper edge for allowing the entry of a printing hammer 24 (shown in FIG. 1). A hole 22b is cut out, an opening 22c is formed in the center for letting the flange 8 in and out, and an arcuate rib 22 defining the upper half of the storage recess 21 is formed on the circumference.
d is provided protrudingly. The upper lid 23 has a bottom plate 22.
A circular window 23a is provided at a position corresponding to the center of the window 23a, and an elastic tongue piece 25 is formed to protrude from the lower end so that its free end reaches the circular window 23a. A substantially conical protrusion 26 is formed on the inner surface of the free end of the tongue piece 25 .

The petal-shaped type wheel 27 housed in the type wheel cassette 20 has a central hub portion 2.
8 and a large number of spoke parts 30 extending radially from the hub part 28 and having letter parts 29 at the ends thereof, which are integrally molded from resin. The hub portion 28 is located on the platen 1 side of the hub portion 28.
At the same time, a cap 31 which acts as a hub portion of the type wheel 27 is fixedly attached. A through hole 32 serving as a support hole is formed in the center of the hub portion 28 and has a diameter substantially equal to the outer diameter of the shaft portion 6 of the drive member 4, and a head of the shaft portion 6 is formed in the center of the cap 31. A through hole 33 having a maximum outer diameter approximately equal to the maximum outer diameter of the portion 5 is formed. Further, as shown in FIG. 5A, a wire spring 34 having a substantially hairpin shape is provided between the hub portion 28 and the cap 31, and both arms of the wire spring 34 are arranged so as to cross the through hole 33. , the distance between the two arms is larger than the tip end diameter of the head 5 of the shaft section 6, and smaller than the maximum diameter of the head 5 by a predetermined amount, and the head 4 is arranged between the two arms. When the head 5 enters between the arms, the arms are pushed apart so that the maximum diameter part of the head 5 can enter between the arms.

A housing recess 35 is provided on the platen 1 side of the hub portion 28, and an insertion hole 36 parallel to the shaft portion 6 is formed between the inner bottom surface of the housing recess 35 and the front surface of the hub portion 28. On the other hand, the cap 31 also has the accommodation recess 35.
A housing recess 37 is provided at a position corresponding to the housing recess 37, and an insertion hole 38 is similarly formed between the inner bottom surface of the housing recess 37 and the outer surface of the cap 31. The accommodation recess 3
5, 37 and the insertion holes 36, 38, a working pin 40 having a latching protrusion 39 as a connecting member is housed so as to be movable back and forth, and either of its front and back ends are connected to the insertion hole 36, 38. 38 so that it can protrude outward. The working pin 40 is biased to protrude rearward by a spring 41. Further, when the front end of the working pin 40 projects forward, the projecting portion engages with the locking projection 1 as the type wheel 27 rotates.
8 to restrict the rotation of the type wheel 27.

This type wheel 27 is stored in the storage recess 21 of the type wheel cassette 20, and
When the drive member 4 is not attached to the shaft portion 6, the tongue piece 25 is attached as shown in FIG. 4B.
The protrusion 26 fits into the through hole 33 of the cap 31, determines the center position of the type wheel 27 with respect to the type wheel cassette 20, and supports the type wheel 27 in a freely rotatable manner.

This printing device also has a cover (not shown).
Closing operation or power switch (not shown)
Control means is provided for rotating the pulse motor 2 in one direction a plurality of times (two rotations in the embodiment) in conjunction with the closing operation. Note that the term "multiple rotations" here refers to a number of rotations greater than one rotation.

Now, in order to attach the type wheel cassette 20 containing the type wheel 27 to the printing device, first open the cover of the printing device and insert the type wheel cassette 20 shown in FIG. 4B into the cassette holder 11 which is in the state shown in FIG. 4A. Type wheel cassette 20 with tongue piece 25
Insert it so that it is located on the platen 1 side. Next, as shown in FIG. 4C, when the pulse motor 2 is moved forward by manual operation of the operating lever, the opening of the type wheel cassette 20, in which the head 5 and the shaft section 6 are in a tilted state, is moved forward. 22c and begins to enter the through hole 32 of the type wheel 27. Then, the head 5 comes into contact with the protrusion 26 of the tongue 25 and presses the tongue 25 toward the platen 1 against its elastic force, so that the tongue 25
The engagement between the protrusion 26 and the through hole 32 of the cap 31 is released. On the other hand, when the position of the engaging part 7 of the flange 8 and the position of the operating pin 40 of the type wheel 27 match, the engaging part 7 and the operating pin 40 are moved by the subsequent rightward movement of the pulse motor 2. The drive portion 4 and the type wheel 27 are connected at a predetermined position in the rotational direction.
If the positions of the engaging portion 7 and the working pin 40 do not match (as shown in FIG. 5A), the end face of the flange 8 and the working pin 40 come into contact. When the pulse motor 2 is further moved to the right from this state, the cassette holder 11 is first rotated upright by the pressing member toward the platen 1 side against the force of the tension spring 19, and the bending latching portion 16 is the hooking part 9b of the fixed plate 9
It is held in a latched state.

This action causes the head 5 of the drive member 4 to move against the wire spring 3.
4, and after the maximum diameter part passes between the two arm parts, the engagement with the wire spring 34 is completed and it is fitted into the through hole 33 of the cap 31, as shown in FIG. 4D. The shaft portion 6 is fitted into the through hole 32 of the hub portion 28, and the positioning of the drive member 4 and the type wheel 27 in the axial direction is completed. The relationship between the flange 8 and the working pin 40 is such that the flange 8 presses the working pin 40 toward the platen 1 side against the force of the spring 41, and the surface of the flange 8 on the platen 1 side comes into contact with the hub portion 28. At the same time, the working pin 40 is pressed against the spring 41.
It is projected forward against the urging force of. On the other hand, the protrusion 26 of the tongue piece 25 is connected to the cap part 31 by the head 5.
The tongue piece 25 is completely pushed out from inside the through hole 33 of the tongue piece 25.
It is located in the space of the cassette holder 11 in a bent state. In this state, the type wheel 27
can rotate together with the driving member 4 by the pressing force of the flange 8 and the frictional force by the wire spring 34.

Thereafter, when the cover of the printing device is closed or the power switch is closed, a rotation support signal is output from the control means so that the pulse motor 2 rotates two rotations, and the drive member 4 rotates through the motor shaft 3. Start rotating in the direction. In this case, at first the drive member 4 and the type wheel 27 rotate as one unit (up to 180 degrees
degree), but as shown in FIG. 5B, the working pin 40
When the protruding end of the type wheel 27 engages with the locking protrusion 18 of the cassette holder 11, the rotation of the type wheel 27 is blocked and only the drive member 4 continues to rotate, and during one further rotation, the type wheel 27 rotates as shown in FIG. 5C. Flange 8
The working pin 40 is engaged with the engaging portion 7 by the biasing force of the spring 41. As a result, as shown in FIG. 1, the type wheel 27 and the drive member 4 are connected in a predetermined relative positional relationship, and positioning in the rotational direction is performed.
The engagement with the drive member 4 and the type wheel 27 are released, and the drive member 4 and the type wheel 27 are stopped in a state where they can rotate together due to the pin engagement. In this way, no matter what rotational position the type wheel 27 is in, the position between the type wheel 27 and the driving member 4 at the tip of the motor shaft 3 is determined during two rotations of the motor shaft 3.
Therefore, it is only necessary to mount the type wheel 27, and the mount control mechanism can be simplified.

Therefore, in this state, type wheel 2
The type wheel 7 is in a state where it can freely rotate with respect to the type wheel cassette 20 and the cassette holder 11, and is rotated together with the drive member 4 by the subsequent rotation of the pulse motor 2, so that the type selection operation of the type wheel 27 is executed as appropriate. .

Next, the operation for taking out the type wheel cassette 20 will be explained.

When the operating lever is operated in the reverse order with the type wheel cassette 20 attached to the cassette holder 11, after the pulse motor 2 starts to move backward, the pressing member separates from the cassette holder 11 and the cassette is removed. Holder 11 is tension spring 1
Due to the urging force of 9, it is tilted rearward. Therefore, the hooking portion 9b of the fixed plate 9 and the cassette holder 11
At the same time, the engagement between the engaging portion 7 of the flange 8 and the working pin 40 is released, and the flange 8 is disengaged from the opening 22c of the type wheel cassette 20 and It comes out of the through hole 17 of the cassette holder 11, and the shaft part 6 is inserted into the hub part 28.
The head 5 is released from the engagement state with the wire spring 34, and the head 5 is completely removed from the through hole 32, and the head 5 is released from the engagement state with the wire spring 34.
Get out of 3 completely. On the other hand, following the movement of the head 5 coming out of the through hole 33 of the cap 31, the protrusion 26 of the tongue 25 enters the through hole 33 due to the elastic force of the tongue 25. In this state, pinch the operation recess 22a of the type wheel cassette 20,
When the type wheel cassette 20 is pulled upward, it can be taken out from the cassette holder 11 with the type wheel 27 stored therein.

Note that without tilting the cassette holder 11,
It is not possible to take out the type wheel cassette 20 while it is in the vertical position shown in the figure, but this is because there is a risk of damaging the ribbon located between the type wheel cassette 20 and the platen 1 if the removal operation is performed in that state. It is.

Note that the present invention is not limited to the above-mentioned embodiments, and for example, instead of the engaging portion of the working pin and the flange, a connecting mechanism using a key and a keyway may be provided between the driving member and the rotating shaft. It is also possible to arbitrarily change the shape, structure, etc. of each part without departing from the spirit of the present invention, such as configuring the key and keyway to rotate together when they match.

[Effect] As detailed above, when the printing device of the present invention attaches the type wheel to the rotating shaft, even when the relative positions of the rotating shaft and the type wheel in the rotational direction are not in a predetermined positional relationship, the connecting member is By rotating the rotary shaft multiple times while engaged with the non-rotating part of the printing device, the rotary shaft and the type wheel can be automatically and reliably connected by the connecting member, making it possible to replace the type wheel. It has excellent effects in that it can be done quickly and easily.

[Brief explanation of drawings]

Fig. 1 is a cross-sectional view of a main part of a printing device embodying the present invention, Fig. 2 is a perspective view showing a driving member, Fig. 3 is a perspective view of a type wheel cassette in which a type wheel is stored, and Fig. 4 A. ~D are partial sectional views for explaining the positional relationship between the drive member and the type wheel, and Figures 5A~C are partial front views for explaining the positional relationship between the working pin of the type wheel and the engaging portion of the flange. It is. Platen...1, Pulse motor...2, Drive member...4, Head...5, Shaft...6, Engagement part...
7, Flange...8, Cassette holder...11,
Type wheel cassette...20, tongue piece...2
5, Protrusion...26, Type wheel...27,
Accommodation recess...35, 37, insertion hole...36, 3
8. Working pin...40, Spring...41.

Claims (1)

[Claims] 1. Petal type wheel 27 and printing impact device 2
4, in which a motor 2 appropriately selects and sequentially prints characters on a type wheel 27, the rotary shaft 6 being driven by the motor 2 and to which the type wheel 27 is removably attached.
and a working pin 40 provided on the type wheel 27 and movable between an engaging position advanced toward the rotating shaft 6 and a retracted retracted position; a spring member 41 formed on the rotary shaft 6 and biasing the rotary shaft 6 toward the rotary shaft 6 when the rotary shaft 6 and the type wheel 27 face each other at a specific rotational position in the rotational direction; An engaging portion 7 that engages with the working pin 40 advanced to the engaging position by the biasing force of the spring member 41; a head 5 having a large diameter portion formed at the tip of the rotating shaft 6; spring means 34 for axial positioning of the type wheel 27 on the rotating shaft 6 by engagement with the rotating shaft 6; applying a frictional force to cause the rotating shaft 6 and the type wheel 27 to rotate together when they are not facing each other in the rotational position; and applying a rotational force to the type wheel 27 based on the frictional force. Time, type wheel 27
and engages with the type wheel 2 against the frictional force.
a rotation prevention means 18 for preventing the rotation of the rotary shaft 6; and a type wheel 27 in a state in which the head 5 of the rotary shaft 6 and the spring means 34 are engaged and the type wheel 27 is positioned on the rotary shaft 6 in the axial direction; wheel 2
7 on the rotary shaft 6 in the rotational direction, the motor 2 is rotated at least a plurality of times, and while the rotation of the type wheel 27 is prevented by the rotation preventing means 18, the rotary shaft is rotated on the working pin 40. and a control means for controlling the type wheel 27 to rotate relative to the type wheel 27 to the specific position where the engaging portion 7 engages. 2. The printing device according to claim 1, wherein the control means is configured to rotate the motor 2 as a cover of the printing device is closed. 3. The printing device according to claim 1, wherein the control means is configured to rotate the motor 2 when a power switch is closed.