JPS6144070B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to a petal-shaped type wheel used in printing devices such as typewriters.

[Objective] The object of the present invention is to determine the relative position in the rotational direction between the rotary shaft rotationally driven by the type selection motor and the type wheel when a petal-shaped type wheel is attached to a printing device. To provide a petal-shaped wheel which can be easily and reliably carried out, has an extremely simple structure, and is convenient for assembly.

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

FIG. 1 is a sectional side view of a 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 a platen 1 is shown. , type selection pulse motor 2
is supported so as to be able to reciprocate in a direction perpendicular to the printing surface. This reciprocating motion 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. As shown in FIGS. 1 and 2, at the tip of the drive member 4, a shaft portion 6 having a head 5 with an approximately hexagonal cross section and a flange 8 having a single notch 7 at the peripheral edge are integrally formed. has been done. This drive member 4 and motor shaft 3
A rotating shaft driven by the pulse motor 2 is configured by the above.

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 and a rear wall 13 on the pulse motor 2 side.
It is formed of a side wall 14 and a lower wall 15 (in this embodiment, the platen 1 side is the front part), and a rear wall 1
3 has a hook 9 formed on the upper part of the fixing plate 9.
A bent hook 16 that can be engaged with the cassette holder 11 is provided, and a through hole 17 is provided for allowing the flange 8 to move in and out of the cassette holder 11. Further, the front wall 1 is located at approximately the same height as the head 5 of the driving member 4.
A pair of latching protrusions 18 (also shown in FIGS. 5A to 5C) as non-rotating portions are protruded from the upper end of 2 at an interval 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 2 defining the upper half of the storage recess 21 is formed on the circumference.
2d is provided protrudingly. The upper lid 23 has a bottom plate 2.
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 substantially hairpin-shaped wire spring 34 is provided between the hub portion 28 and the cap 31, and both arms thereof are arranged 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 5 is arranged between the two arms. When the head 5 enters, both 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 is accommodated so as to be movable back and forth, and either of its front and rear ends is directed outward from the insertion holes 36, 38. It has become possible to protrude to The working pin 40 is biased to protrude rearward by a spring 41.
Further, when the front end portion of the working pin 40 projects forward, the projecting portion is latched to the latching projection 18 as the type wheel 27 rotates.

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 to center the type wheel 27 with respect to the type wheel cassette 20 and to support 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)
A well-known control means is provided for rotating the pulse motor 2 in one direction a plurality of times (twice 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 insert the cassette holder 1 in the state shown in FIG. 4A.
1, insert the type wheel cassette 20 into the platen 1 so that the tongue piece 25 is positioned on the platen 1 side, as shown in FIG. 4B. Next, as shown in Figure 4C,
The pulse motor 2 is activated by manual operation of the control lever.
When the type wheel cassette 20 is moved forward, the head 5 and the shaft 6 pass through the opening 22c of the type wheel cassette 20, which is in an inclined state, and pass through the through hole 3 of the type wheel 27.
2 begins to enter. And the head 5 is the tongue piece 2
5, press the tongue piece 25 against the elastic force of the tongue piece 25 toward the platen 1 side, and as shown in FIG.
The engagement with the through hole 33 is released. On the other hand, the position of the notch 7 of the flange 8 and the type wheel 27
When the position of the working pin 40 matches that of the working pin 40, the working pin 40 located at the coupling position is reliably moved to the cutout part 7 by the action of the spring 41 as the pulse motor 2 moves to the right. The drive member 4 and the type wheel 27 are connected at a predetermined position in the rotational direction.
If the positions of the flange 8 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 with each other. 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 held in a latched state by the latching portion 9b of the fixed plate 9.

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 to the front restriction position against the urging force of.
On the other hand, the protrusion 26 of the tongue piece 25 is completely pushed out from the through hole 33 of the cap part 31 by the head 5,
The tongue piece 25 is located in the space of the cassette holder 11 in a bent state. In this state, the type wheel 27 applies the pressing force of the flange 8 and the wire spring 34.
The type wheel 27 can rotate together with the drive member 4 due to the frictional force, and relative rotation between the drive member 4 and the type wheel 27 is possible against the frictional force.

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
゜), but as shown in Fig. 5B, the working pin 4
The protruding end of 0 is the latching protrusion 18 of the cassette holder 11.
When engaged, the rotation of the type wheel 27 is blocked and only the drive member 4 continues to rotate, and during one further rotation, the working pin 40 is inserted into the notch 7 of the flange 8 as shown in FIG. 5C. The engagement is ensured by the biasing force of the spring 41. As a result, the type wheel 27 and the drive member 4 are connected in a predetermined relative positional relationship as shown in FIG. is released, and the driving member 4 and the type wheel 27 are brought into a state where they can rotate together through pin engagement. Thereafter, the drive member 4 is stopped after making two revolutions from the start.

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, when the type wheel 27 is mounted, the motor shaft 3 only needs to rotate twice, and the control mechanism for printing operations 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 moves against the cassette holder 11.
The cassette holder 11 is disposed at an angle further to the rear of the biasing force of the tension spring 19. Therefore, the hooking portion 9b of the fixed plate 9 and the cassette holder 11
At the same time, the engagement between the notch 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, the shaft part 6 completely comes out of the through hole 32 of the hub part 28, the head part 5 is released from the engaged state with the wire spring 34, and the through hole 3
Completely escape from 2.33. 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, by pinching the operation recess 22a of the type wheel cassette 20 and pulling the type wheel cassette 20 upward, the type wheel 27 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.

Moreover, the assembly of such type wheel 27 is as follows:
First, insert the spring 41 onto the working pin 40, and then insert the type wheel 27 so that the spring 41 is sandwiched between the type wheel 27 and the cap 31.
When the cap 31 is attached to the cap 7, the working pin 40 is movable and supported by the type wheel 27 and the cap 31 while being urged forward by the spring 41, making assembly extremely easy.

It should be noted that the present invention is not limited to the above-mentioned embodiments, and the shape, structure, etc. of each part can be arbitrarily changed without departing from the spirit of the present invention.

[Effects] As described in detail above, the present invention engages the petal-shaped wheel with the flange of the rotating shaft driven by the motor to engage the rotating shaft and the petal-shaped wheel, and a working pin that engages with a non-rotating portion of the printing device to cause a relative rotational movement therebetween when the relative positions in the rotational direction are not in a predetermined positional relationship; By providing a spring that applies spring force in the engagement direction, despite the extremely simple structure, the type wheel and rotation shaft can always be connected reliably and quickly. The control mechanism of the printing device can be simplified.

In addition, since the working pin is movably supported by the type wheel and the cap, and a spring is provided on the working pin between the type wheel and the cap, it can be assembled very easily. play.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of the main parts 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. 4A ~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 notch of the flange. It is. Platen...1, Pulse motor...2, Drive member...4, Head...5, Shaft...6, Notch...7, Flange...8, Cassette holder...1
1. Type wheel cassette... 20. Tongue piece...
25, Protrusion...26, Type wheel...2
7, Accommodation recess...35, 37, Insertion hole...36,
38, Working pin...40, Spring...41.

Claims (1)

[Claims] 1. A printing impact device 24, rotating shafts 3 and 4 driven by the motor 2, and a petal-shaped wheel 27 detachably mounted on the rotating shafts 3 and 4.
In the printing device, the characters on the petal-shaped type wheel 27 are appropriately selected as the rotating shafts 3 and 4 rotate, and printing is performed sequentially by the printing impact device 24. A cap 31 attached to one side, the rotating shafts 3 and 4, and a petal-shaped wheel 27.
are in a predetermined positional relationship, one end side engages with the flange 8 of the rotating shafts 3, 4 to connect the rotating shafts 3, 4 and the petal-shaped wheel 27; 27 is not in a predetermined positional relationship, one end side contacts the flange 8 to allow relative rotation between the rotating shafts 3, 4 and the petal type wheel 27, and the other end side contacts the non-rotating part of the printing device. The petal-shaped wheel 27 and the cap 31 are movable between a regulating position where the petal-shaped wheel 27 and the cap 31 are engaged with each other to restrict rotation of the petal-shaped wheel 27.
a working pin 40 supported by the petal-shaped wheel 27 and the cap 31;
A petal-shaped wheel characterized in that a spring 41 is provided on the working pin 40 located between them and biases the working pin 40 toward the flange 8.