JPS5887057A - Printer - Google Patents

Abstract

PURPOSE:To provide a carry control mechanism of very simple construction capable of performing accurate carry operation by a method wherein an endless rack belt is coupled with a drum gear which is integrally constructed with a type drum and a stop lever is provided so that it can be caused to couple with the rack belt at a specified timing. CONSTITUTION:A worm shaft 20 is coupled with a drum gear 23 constructed integrally with a type drum provided on a carriage 22 and it is caused to rotate by a motor 21. At the other side of the drum gear 23 opposing to the worm shaft 20, an endless rack belt 24 is installed by means of rollers 25, 26 so that it is brought to the stretch. This rack belt 24 is caused to attach to or detach from the coupling section 28a at one end of a stop lever 28 by a solenoid 27. When coupled, the rack belt 24 stops, and the type drum and the carriage 22 perform carry operation as they move in response to the advance pitch of the worm shaft 20, and at the same time, the drum gear 23 performs rolling movement on the pitch circumference of the surface at which it is brought to contact with the rack belt 24. At this time, a hammer is caused to hit.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a printer, and more particularly to a printer with a completely improved girder mechanism.

The small printer according to the present invention employs the basic structure shown in FIGS. 1 to 3, for example, and has been proposed previously.

That is, in the figure, reference numeral 1 is a type drum, which has one hole 1a, and on its surface, a type belt 2 made of an elastic part such as rubber is wound around the outer periphery of a base 1. has a type 2a and a protrusion 2b that fits into the hole 1a on the opposite side of the type 2a, and this protrusion 2b is inserted into the type drum 1.
If it is suppressed from inside, the type 2a will pop out.

Reference numeral 3 denotes a drum shaft, which is fixed to the type drum 1, supported by a carriage 4 (which can rotate twice), and has a drive gear 5 fixed to the other end.

6 is a worm gear, which connects the bent portions 4a and 4b of the carriage 4.
The thrust direction is regulated by the worm gear shaft 7 (the worm gear shaft 7 is held by a second screw) and meshes with the drive gear 5.

Similarly, the worm gear shaft 7 is rotatably supported between side plates (not shown) and rotated at a predetermined rotational speed by a drive motor (not shown). Further, the worm gear shaft 7 has an oval-shaped cross section and is slidably engaged with an oval-shaped hole provided in the worm gear 6.

Reference numeral 8 denotes a drum control member which has rack-shaped teeth and can engage with the drive gear 5 when pressed toward the drum by a solenoid (not shown).

Reference numeral 9 denotes a printing cam, and cam portions 9a for pressing a hammer 10, which will be described later, are provided on the end face at a predetermined pitch.

Reference numeral 10 denotes an arm 10a that holds a roller 10b for pressing the protrusion 2b of the type 2a with a printing hammer, and the printing cam 9.
It has a suppression arm 10c that engages with the carrier 4, and is rotatably supported on a hammer shaft 11 provided on the carrier 4.

12 is a platen, and 13 is printing paper.

15 is pressed against the type drum by an ink roller, and the type surface (-
Transfer ink.

The carriage 4 is guided by a guide shaft (not shown) so that it can move parallel to the platen 12.

Reference numeral 14 is a return spring, which always pulls the carriage) 4 in one direction (two directions).

Next, the operation of the printing (3) mechanism of this embodiment constructed as described above will be explained with reference to FIGS. 1, 2, 3, and 4.

When the worm gear shaft 7 is rotated in the direction A by a motor (not shown), the worm gear 6, which is engaged in a bidirectional configuration, also rotates in the same direction. Drive gear 5 is worm gear 6
Since the drive gear 5 also rotates in the direction B, the type drum 1 which is fixed to the drum shaft 3 together with the drive gear 5 rotates in the direction B.
also rotates in direction B (Fig. 2.3 (A)).

Now, if you want to print the desired type 1a, then the gear 5 with teeth corresponding to the type drum 1 will be connected to the IJ.
The control member 8 is pushed forward by a solenoid (not shown) in order to engage the rack teeth 8 of the control member 8 at a predetermined position.
a and the teeth 5a of the drive gear 5 (Fig. 2 (
B)).

Since rotational force is still being applied to the drive gear 5, the drive gear 5 tries to rotate around the rack (i8a) of the control member 8, and as a result, the rotation center of the drive gear 5 becomes D.
This will lead to a shift to E (Figure 2 (B)). This state is exactly the same as when the rack and pinion (4) mesh and the pinion rolls on the rack while bending over each other.

When the type drum 1 moves in the column direction C while rolling, the carriage 4 similarly moves in the column direction C.

A rotatably supported hammer 10 is provided on the carriage 4, and a pressing arm 10c of the hammer 10 engages with a cam portion 9a of the printing cam 9. When the hammer 10 moves in the digit direction C together with the carriage 4, the suppressing arm 10c tries to get over the cam part 9a and rotates in the E direction, and the pressing roller 10b presses the protrusion 2b of the type belt 2, and the type character is in contact with the printing paper 13 and transfers the ink (Fig. 3 (B)).Furthermore, the carriage 4
, the type drum 1 and the hammer 10 move as one in the digit direction C, and when the pressing arm 10c of the hammer 10 rides over the cam portion 9a of the printing cam 9, the type also moves onto the printing paper 1.
3, the printing operation ends (Fig. 2.3 (C)).

At this point, the solenoid that was pressing the control unit 4N8 is de-energized, the control member 80 and the drive gear 5 are disengaged, and the type drum 1 stops its rolling motion and remains in place. Continue the rotational movement (Figure 2.3 (C)). At this time, the return pie 14 is pulling the carriage 4, but it is not returned because the 41p pressure arm 10c of the hammer 10 is engaged with the cam portion 9a of the printing cam 9 (the third
Figure (C)).

Similarly, if printing is performed sequentially and the printing cam 9 is moved away from the type drum 1 after printing one line, the suppression arm 10c of the marker 10 will be released from the cam section. It is then returned to a predetermined position by the tension of the return spring 14.

When printing one line, the printed value is 1.2, 3.4...
If it is continuous like..., the extrusion of member 8 is 1
High-speed printing is possible because printing and movement are carried out in sequence. Similarly, the printing pitch (digit spacing) is mx, where m is the tooth module of the drive gear 5. In addition, the control section (・A
The rack pitch of 8 and the cam pitch of I:11-shaped cam 9 are also the same (2 mx).

A serial printer having a structure as described in 1-1 below has a control mechanism consisting of the rack teeth 8a of the control section 8 and the worm gear 6 (= therefore, M
i The movement of the control member 8 was carried out by a solenoid (not shown). In other words, the rack teeth of the control member 8 were inserted into the worm gear 6 (2) and engaged (by the advance pitch of the worm gear). It uses a structure in which the type drum integrated with the worm gear is rolled and pressed into contact with each other to simultaneously print.

However, if such a double-digit control mechanism is adopted, a large solenoid is required to move the rack plate, which has a large mass, which not only increases the size of the device, but also causes the rack to move due to the rotating worm gear. There was a lot of wasted time trying to get the board to jump in, the timing was difficult, and sometimes the rack board was thrown off, making it difficult to get the correct digits right.
There were drawbacks such as the inability to perform niage.

The present invention was made in order to eliminate the following drawbacks of the conventional technology, and has an extremely simple structure (more than two orders of magnitude more reliable).
(7) An object of the present invention is to provide a printer equipped with a digit one-up control mechanism configured to be able to perform two-up operations.

In order to achieve the object of the present invention (part 2), item 1, a sparge control member is provided with a drum gear integrated with a type drum;
We adopted a structure that includes a rack belt that fits together and a stop lever that engages the rack belt at a predetermined timing.

Hereinafter, the present invention will be described in detail based on embodiments shown in the drawings.

FIG. 4 explains one embodiment of the present invention. In the figure, reference numeral 20 indicates a worm shaft which is rotated by a motor 21. In FIG. A drum gear 23 that is integrated with a type drum (not shown) provided on a carriage 22 is meshed with the worm shaft 20 . The drum gear 23 is rotatably attached to the gear ridge 22, has teeth corresponding to the type characters on the type drum, and is rotated by the worm shaft 20.

On the other hand, on the opposite side of the worm shaft 20 with the drum gear 23 in between, an endless rack belt 24 is connected to a roller 25.
, 26. The reference numeral 27 indicates a solenoid, and a stop lever 28 is connected to the tip of its rod (8) 27a. One end of the stop lever 28 is rotatably supported on a fixed part of the device via a shaft 29, and a retaining part 28a protruding from the other end faces a position where it can mesh with the rack belt 24. . This stop lever 28 is a spring 30
This gives the retaining portion 28a the ability to rotate in the direction away from the rack belt 24.

Next, the operation of this embodiment configured as described above will be explained.

The drum gear 23 is rotated by the worm shaft 20 at a position supported by the carriage 22, and the teeth of the drum gear corresponding to the type to be printed on the type drum integrated with the drum gear mesh with the rack belt 24. When the solenoid 27 is energized, the stop lever 28
is rotated clockwise in FIG. 4, and its retaining portion 28a meshes with the rack belt 24.

As a result, the rack belt 24, which had been in a free state and was driven by the drum gear 23, stops;
Since the drum gear 23 is still being rotated by the worm shaft 20, the center of the drum gear 23, in other words, the type drum (not shown) and the carriage 22 move in accordance with the advancing pitch of the worm shaft 20, and the drum gear 23 moves as shown in FIG. Rolling motion is carried out on the pitch circumference of the surface in contact with the rack belt 24. At this time, the characters on the type belt attached to the type drum are made to fly out using a hammer (not shown), and are brought into rolling pressure contact with the printing paper to perform printing.

After printing is completed, when the solenoid 27 is de-energized, the stop lever 28 is returned by the spring 30 (-), the retaining portion 2Ba and the rack belt 24 are disengaged, the rack belt 24 starts running again, and at the same time the drum gear 2
3 stops moving and rotates at that position to select the next type to be printed.

Thereafter, in the same manner, the selection of characters and the operation of pushing the digits are repeated, and printing is performed in sequence.

As is clear from the above description, according to the present invention, a rack belt is provided which is always in mesh with the drum gear that rotates the type drum, and the rack belt (2) is engaged by driving a solenoid at a predetermined timing. Since it adopts a structure with a matching stop lever, the solenoid (-) can be activated, reducing the time required for the stop lever to engage with the rack belt, and enabling high-speed printing.

[Brief explanation of drawings]

Figures 1 to 3 illustrate the basic structure of the present invention.
Figure 1 (A) is a perspective view of the carriage part, Figure 1 (B)
Figures 2 (A) to (D) are longitudinal sectional side views of the carriage part.
3 is an explanatory diagram explaining the operation of the drive gear and rack teeth.
Figures (A) to (C) are explanatory views showing printing conditions, and Fig. 4 is a plan view showing an embodiment of the present invention. 20... Worm shaft 21... Motor 22.
...Carriage 23...Drum gear 24...
・Rack belt 27... Solenoid 28...
Stop lever 30...Spring (11) (A) * 30 (B) (C) M/',"h

Claims (1)

[Claims] A printer (two printers) comprising a type drum that rotates in the direction of the printing digits, a carriage that conveys this type drum, and a control unit that rotates and moves the type drum, and performs printing by rolling and connecting the type drum with a printing surface. In addition, the control member includes an endless rack belt that meshes with a drum gear that rotates a type drum provided on the carriage, and a stop lever that meshes with the rack belt at a predetermined timing. A printer characterized by: