JPS6027580B2 - printing device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a printing device for printing characters, numbers, etc. on printing paper or the like.

There is a dedicated motor for feeding the paper in the printer.
The paper was fed by one line each time a line was printed.

However, such a device requires two motors, one for rotating the print body and the other for paper feeding.
The motor that instantaneously feeds the paper must have good start-up characteristics, and its peripheral equipment is also complicated. SUMMARY OF THE INVENTION An object of the present invention is to eliminate the various drawbacks of the conventional apparatus described above and to provide a printing apparatus equipped with a paper feeding mechanism that gradually feeds paper during printing. The printing device of the present invention includes a paper feed roller provided opposite to a print body rotated by a rotational drive source, and in which the print body prints on a print sheet conveyed by the paper feed roller. A cam member that rotates in synchronization with the font, and a shape that is formed on the cam member so as to revolve around the center of rotation, and that the distance from the center of rotation gradually changes from one end to the other end while keeping the direction constant. and a cam surface forming a step between the one end and the other end, and a protrusion in sliding contact with the cam surface, and the protrusion slides from the one end to the other end at the step. and a lever that rotates the paper feed roller via a ratchet mechanism that operates in a counter-east direction when moving, and the stepped portion is configured to correspond to a non-printing position at the end of rotation of the printing body.

Hereinafter, one embodiment of the present invention will be described based on the drawings.

The printed body 1 is rotatably supported by each end of the levers 3 and 4 via a shaft 2, and a hem-shaped protrusion la is formed on the outer surface of the printed body 1.

On the surface of this helical protrusion la, a large number of protruding points la', la'... are formed at regular intervals, and the protruding points la', la'...... are formed by these protruding points la', la'... Letters, numbers, etc. are formed by combining the printed points.
A gear lc is fixed to the negative side of the printed body 1, and a cam member ld is fixed to the bottom side. 1 is a cam surface of this cam member ld, and this cam surface ld'' is formed so as to revolve around the center of rotation of the cam member ld (here, the heart of wisteria 2), and from one end to the pond edge. As the distance from the center of rotation increases, the distance from the center of rotation gradually changes while keeping the direction constant (that is, it gradually decreases here).

) shape. Here, assuming that the outer peripheral surface of the cam member ld is a flat surface, the cam surface ld' is a dovetail slope, and there is a stepped portion 4d between one end and the other end.
This stepped portion ld'' corresponds to the non-printing position at the end of the rotation of the printing body 1. 5
1 is a paper feeding lever, and this paper feeding lever 5 has a protrusion 5a that slides into engagement with a cam surface 1d''.

The levers 3 and 4 are each rotatably attached to a shaft 6, and gears 7 and 8 are fixed to the shaft 6, respectively.

The gear 7 is connected to a motor M, which is a rotational drive source, via a gear 9, and the gear 8 meshes with the gear lc of the printed body 1. Therefore, when the motor M rotates, its rotational force is transmitted to the gear 9, the gear 7, the gear 6, the gear 8, and the gear lc in this order, and thus the printed body 1 rotates. On the other hand, a gear assembly 11 is also rotatably attached to the lever 4 via a shaft 10, and the gear assembly 11 has ratchet teeth 11a.
and a gear 11b are combined and fixed to each other.

A stopper 12 driven by a small-capacity solenoid (not shown) is rotatably supported on the ratchet tooth 11a around a shaft 12a, and is positioned so as to be engaged with the ratchet tooth 11a.
1b is always meshed with gear lc. That is, the forced stop means is composed of the gear combination 11, the stopper 12, and a small capacity solenoid (not shown). Note that 13 and 14 indicate the degrees of contact of the levers 3 and 4, respectively. 15 is an ink roller, and ink roller 1
5 is always applied to the outer surface of the printed body 1 and applies ink to the helically arranged protruding points la', 1. Next, a paper feeding mechanism for the printing paper 16, which is the object to be printed, will be explained. The paper feeding lever 5 described above is rotatably attached to a rotating shaft 17 disposed parallel to the shaft 2, and ratchet teeth 5b are formed on one side of the lever 5. The ratchet teeth 5b mesh with the ratchet teeth 18a of a ratchet plate 18 fixed to the shaft 17, and the lever 5 and the ratchet plate 18 form a kind of one-way clutch, and these constitute a ratchet mechanism.
When the protrusion 5a falls down the stepped portion ld', it moves in a counter-east direction so as to shift by one tooth. A paper feed loaf 19 is fixed to the ratchet 17, and the printing paper 16 is in frictional contact with the outer surface of the roller 19.
Therefore, the printing paper 16 is fed at a predetermined speed as the roller 19 rotates. Also,. -La 19
It goes without saying that is placed at a position facing the printed body 1. On the other hand, a spring-engaging protrusion 5c is formed on the outer surface of the paper feed lever 5, and a leaf spring 20 has its tip abutted against this protrusion 5c.

Due to the elastic force of the leaf spring 20, the lever 5 is moved toward the shaft 1 in FIG.
The levers 3 and 4 are also urged to rotate clockwise around the shaft 6 via the protrusion 5a, the cam surface ld', and the shaft 2. dynamically energized,
The levers 3 and 4 are stopped at 13 and 14 degrees, respectively. Further, a switch bushing piece 21 is disposed opposite to the two leaf springs, and a signal generated when the switch piece 21 and the leaf spring 20 are separated can be used as a printing start position setting signal.

The action will be explained below.

When the motor M is rotated, the printing body 1 is rotated in the A direction due to its rotational force, and at the same time, the cam member ld is also rotated in the A direction.

As the cam member ld rotates, the protrusion 5a slides along the cam surface l, so the lever 5 rotates in the direction B in FIG. 2 while resisting the elastic force of the spring 20. ratchet teeth 5
The roller 19 rotates in direction B via b and 18a. When the roller 19 rotates, the printing paper 16 is continuously fed in the C direction at a constant speed, and when the cam member ld makes one revolution, the feeding amount is only a magnitude a shown in the fourth figure. Print body 1
rotates and reaches the position where printing is to be performed, a solenoid (not shown) rotates the stopper 12 in the direction ○, and the stopper 12
and the ratchet teeth 11a, and the gear combination 11
The rotation in the D direction is stopped.

At this time, since the gear lc of the printed body 1 and the gear 11b of the gear assembly 11 are meshed with each other, the rotation of the gear lc stops and at the same time a reaction force is applied to the levers 3 and 4 in the E direction around the shaft 6. (rotational force) is generated, and this reaction force causes one of the protruding points la', la', .
Needless to say, the printing paper 16 is sandwiched between the printing body 1 and the roller 19 during printing. When printing is completed, the solenoid is deenergized and the stopper 12 and ratchet tooth 1 are closed.
1a and return the printed body 1 to its original position. In this manner, the first line 16a in FIG. 4 is printed while the printing body 1 rotates once.

During this time, since the printing paper is continuously fed, the first line 16a is skewed by the size a on the left and right sides, but this does not pose any practical problem. When the printed body 1 rotates once, the protrusion 5a falls at the stepped portion ld'' of the cam surface ld', and the meshing of the ratchet teeth 5b and 18a shifts by one tooth.
Subsequently, printing of the second line 16b is started.

When the protrusion 5a falls, the spring 20 releases the switch rear piece 21.
The signal generated at this time is used as the printing start position setting signal. In this way, in the illustrated embodiment, printing is performed from line 16a to line 16g by seven rotations of printing body 1, resulting in a total of 1
Printing of the line ends.

FIG. 5 shows another embodiment of the present invention, which is characterized in that the printed body 1' itself is formed into a helical shape.

It is clear that by doing this, the printed body 1' becomes lighter and as a result the inertial force is reduced, so that the response is improved. Further, letters, numbers, etc. may be directly formed instead of the protrusions la'. Further, as the forced stopping means, means for stopping the gear 7 can also be used.

As explained above, according to the present invention, the protrusion of the lever section is brought into sliding contact with the cam surface having the stepped portion of the cam member that rotates in synchronization with the printing body, and the paper is fed through the ratchet mechanism on the lever section. Because the rollers are driven to rotate, it is possible to feed the printing paper gradually and continuously during printing, so unlike instantaneous paper feed type printing devices, the ability to follow the paper feed to the printing operation and its drive power is This eliminates the need for consideration of
As a result, the device can be made smaller and simpler.

Furthermore, in the present invention, the step portion for operating the ratchet mechanism in the opposite east direction corresponds to the non-printing area at the end of rotation of the printing body, and the step portion provides continuity to the cam surface. Since the cam surface is formed so as to revolve around the rotation center of the cam part, during printing, the paper can be fed continuously and at a constant speed as much as possible without being interrupted by parts other than the stepped portion of the cam surface. Therefore, it is possible to obtain a straight printing condition.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a plan view of the entire device of the present invention, Fig. 2 is a right side view of Fig. 1, Fig. 3 is a left side view of Fig. 1,
FIG. 4 is a front view of the printing paper, and FIG. 5 is a perspective view showing another embodiment of the printing body.

1...Printed body, la...projection, lc...gear, l
d...Cam member, ld'...Cam surface, ld''...
Step portion, 3, 4... Lever, 5... Paper feeding lever, 5b, 18a... Ratchet tooth, 11... Gear combination, 12... Stopper, 16... Printing paper, 1
9... Paper feed roller, 20... Leaf spring.

Figure 1 Figure 5 Figure 2 Figure 4 Figure 3

Claims (1)

[Claims] 1. In a printing device in which a paper feed roller is provided opposite to a print body rotated by a rotational drive source, and the print body prints on a print sheet conveyed by the paper feed roller, a cam rotates in synchronization with the print body. a member, the cam member is formed around the center of rotation of the cam member, and has a shape in which the distance from the center of rotation gradually changes from one end to the other end while keeping the direction constant; It has a cam surface that forms a stepped portion between the other end and a protrusion that slides into contact with the cam surface, and when the protrusion moves from the one end to the other end at the stepped portion, a repulsive bundle is generated. A printing device comprising a lever for rotating the paper feed roller via a ratchet mechanism that operates in the direction, and the step portion corresponds to a non-printing area at the end of rotation of the printing body.