JPS5887083A - Printer - Google Patents

Abstract

PURPOSE:To obtain a printer capable of stably and exactly doing carrying work by providing a rack plate with rack teeth, a carriage with a rotator having worm gear engaging with the rack gear, and a pulse motor to turn the rotator. CONSTITUTION:A carriage 20 is slidably attached to a rotary shaft 23 to be turned by a pulse motor 22, and a rotator 24 with a worm gear 25 is provided to the carriage 20. The rotator 24 can turn integrally with the shaft 23, although it can slidably move to the shaft 23. The worm gear 25 of the rotator 24 is coupled with the rack gear 26a of the rack plate 26. When turning the rotator 24 one time by means of the pulse motor 22 when types come into contact with a printing face 27, the carriage 20 is moved by the advancing pitch of the worm gear 25. Synchronously with the movement, a type drum 21 is turned, types are pushed out by a hammer, and printing is made while pressing the types on the printing face 27.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a printer, and more particularly to a small serial printer having an improved carry mechanism.

The small-sized printer according to the second invention adopts the basic structure as shown in FIGS. 1 to 3, as previously proposed.

That is, in the figure, reference numeral 1 denotes a type drum, which has a plurality of holes 1a, and a type belt 2 made of elastic material such as rubber is wound around the outer periphery of a base 1 on its surface.
(- indicates type 2a, etc., and holes 1a and 1β are on the opposite side from type 2a.
It has a mating protrusion 2b, and when this protrusion 2b is pressed from inside the type drum 1, the type 2a pops out.

Reference numeral 3 denotes a drum shaft, which is fixed to the type drum 1, supported for one rotation by a gear ridge 4, and has a drive gear 5 fixed to the other end.

6 is a worm gear, the bending sound l54a of the carriage 4,
The thrust direction is regulated by 4b, and the worm gear shaft 7 meshes with the drive gear 5 and is held by the worm gear shaft 7.

The worm gear shaft 7 can rotate between thin plates (not shown).
It is supported on two supports and is driven by a drive motor (not shown) at a predetermined rotation speed. Also, the worm gear shaft 7
has an oval-shaped cross section and is slidably engaged in a similarly 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 first drive gear 5 when a solenoid (not shown) is pressed toward the drum.

Reference numeral 9 denotes a printing cam, and cam portions 9a for pressing a hammer 10, which will be described later, are provided at a predetermined pitch at the end (11).

10 has an arm 10a that holds a roller 10b for pressing the back protrusion 2b of the type 2a with a printing hammer, and a pressing arm 10c that engages with the printing cam 9, and a hammer shaft provided in the gear rear 4. 11, it is rotatably supported by C'''.

12 is a platen, and 13 is printing paper.

An ink roller 15 presses against the type drum and transfers ink onto the type surface.

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

14 is a return spring that always pulls the carriage 4 in one direction.
ing.

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 17 is rotated in the direction A by a motor (not shown), the worm gear 7 and
Gear 6 also rotates in the same direction. Since the drive gear 5 is meshed with the worm gear 6, the drive gear 5 also rotates in the B direction, and the typeface Drano 1 fixed to the Drano shaft 3 also rotates in the B direction (second and third Figure (A)).

Now, if you want to print the desired type 1a, use the gear 5 with teeth corresponding to the type drum 1, for example 5a.
In order to engage the control part 8 at a predetermined position, the control part 8 is pushed forward by a solenoid not shown in 12cl, and the rank teeth 8a of the control part 8 are engaged with the teeth 5a of the drive gear 5 (second
Figure ([31).

Since rotational force is still applied to the drive gear 5, the drive gear 5 attempts to rotate using the rack teeth 8a of the control unit 8 as a fulcrum, and as a result, the center of rotation of the drive gear 5 shifts from D 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 meshing with 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.

Gear ridge 4 (second is rotatably supported hammer 10
Further, the pressing arm 10c of the hammer 10 engages with the cam portion 9a of the printing cam 9. When the hammer 10 moves in the column direction C together with the carriage 4, the suppressing arm 10c tries to get over the cam part 9a, rotates in the E direction, and the pressing roller 10b moves against the type belt 2.
The back protrusion 2b is pressed, and the letters come into contact with the printing paper 13 and the ink is transferred (FIG. 3(B)). Furthermore, carriage 4
, the type drum 1 and the hammer 10 move as one in the digit direction C, and when the suppressing arm 10c of the hammer 10 gets over the cam portion 9a of the printing cam 9, the type also hits the printing paper 13. The printing operation ends when the paper is separated. (Figures 2 and 3 (C)
) If the solenoid that was pressing the control assembly 8 is de-energized and the rack teeth 8a of the control assembly 8 are disengaged from the drive gear 5, the type drum 1 will stop rolling. It continues to rotate on the spot (Figures 2 and 3 (C)). At this time, the return pipe 14 pulls the carriage 4 and moves it 17, but it is not returned because the pressing arm 10c of the hammer 10 is engaged with the cam gI59a of the printing press 9 (see Fig. 3). 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 pressing arm 10c of the hammer 10 will be released from the grip. , the tension of the return spring 14 (returns to the predetermined position from 2).When printing one line, the printed value is 1.2, 3.4...
In the case of continuous printing as shown in FIG. 1, the extrusion of the member 8 is performed once, and the printing and movement are continued, so high-speed printing is possible. Note that the printing pitch (digit spacing) is mx, where m is the tooth module of the drive gear 5. Also, the rack pitch of the control section assembly 8 and the cam pitch of the printing cam 9 are also the same (2 mx).

In the serial printer having the above structure, the second control mechanism is composed of the rack teeth 8a of the control member 8 and the worm gear 6 as described above, and the movement of the control member 8 is controlled by a solenoid (not shown). It was carried out by For this reason, the rank teeth of the control member 8 are inserted into the worm gear 6 and engaged with each other, thereby rolling and moving the type drum integrated with the worm gear by the advancing pitch of the worm gear. .

However, since the rack teeth perpendicular to the rotating direction of the worm gear 6 jump into the rotating worm gear 6, the timing is difficult, and in some cases, the rack teeth are blown off, resulting in problems such as not being able to jump into the worm gear 6.

The present invention has been made in order to eliminate the above-mentioned drawbacks of the conventional art, and provides a printer having a digit control mechanism configured to ensure carry with an extremely simple structure. It is intended to.

In order to achieve the above objects, the present invention (-) g2,
As a carry control member, the rack plate is engaged with the carriage (nira (7) ohm), and the rotating body is rotated by a pulse motor in synchronization with the rotation of the type drum, and the type drum is Adopts a structure that uses weight and pressure contact.

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

The fourth factor is to explain an embodiment of the present invention, and what is indicated by the reference numeral 20 in the figure is a carriage, and a type drum 21 is rotatably attached to this carriage 20, and is driven by a motor (not shown). be rotated. The carriage 20 is slidably attached to a rotating shaft 23 which is rotated by a pulse motor 22 in the +''-axial direction.

Further, the carriage 20 is provided with a rotating body 24,
A worm gear 25 is formed in a part of this rotating body 24, and this rotating body 24 is configured so that it can slide freely on two rotating shafts 23 (but can only rotate integrally with the shaft 23). ing.

The worm gear 25 of the rotating body 24 meshes with the rank teeth 26a of the rack plate 26(8). Reference numeral 27 indicates a printing surface.

Next (2) The operation of this embodiment configured as above will be explained.

The type drum 21 is rotated by a motor (not shown) (c) When the type to be printed contacts the printing surface 27C, the rotary body 24 is rotated once by the pulse motor 22. The worm gear 25 and the rack teeth 27a of the rotary body 24 rotate. They are in mesh with each other, and the advancing pitch of the worm gear 25 of the rotating body 24 moves the gear ridge 20 in the direction of rotation of the type drum 21.

At this time, by synchronizing the moving speed of the carriage 20 and the rotational speed of the type drum (the type drum 21 rotates on the printing surface 21 and simultaneously pushes out the type with a hammer (not shown), against the printing paper. It will be printed by rolling.

In this way (2), since the present invention does not adopt a method in which the rack teeth are inserted into the worm gear rotating at high speed, the timing of meshing the two is difficult and can be avoided as in the conventional method. This problem does not occur, and the carry operation can be performed reliably.

As is clear from the above description, the present invention adopts a structure in which a rotating body having a worm gear is provided on the gear ridge, the worm gear and rack teeth are always kept in mesh, and the rotating body is rotated by a pulse motor. Therefore, unlike the conventional structure in which the rack teeth are inserted into the worm gear, there is no difficulty in timing, and the printer is equipped with a simple carry control mechanism that can perform reliable carry operations. can be provided.

[Brief explanation of the drawing]

Figures 1 to 3 illustrate the basic structure of the present invention.
Figure 1 (3) is a perspective view of the carriage part, Figure 1 (B)
is the longitudinal cross section of the carriage part () III and Figure 2 (A)
~(D) is an explanatory diagram showing the operation of the drive gear and rack teeth,
Figures 3(A)-(C1 is an explanatory diagram showing the printing state, 4S4
The figure is a plan view showing one embodiment of the present invention. 20... Carriage 21... Type drum 22
...Pulse motor 23...Rotating shaft 24...Rotating body 25...Worm gear 26...Rack plate 26a--Rack teeth. Patent applicant Canon Electronics Co., Ltd. Agent Patent attorney Taku Kato (1'l) False 1゜ (B)

Claims (1)

[Claims] It is equipped with a type drum that rotates twice in the same direction as the printing digit direction, a carriage that conveys the type drum, and a control member that moves the type drum, and prints by rolling and pressing the type drum against the printing surface. A rack plate having rack teeth as the control member;
A printer comprising: a carriage having a rotating body having a worm gear that meshes with the rack teeth; and a pulse motor rotating the rotating body.