JPH03211072A - Type printer - Google Patents

Abstract

PURPOSE:To ensure that sheets are fed if a load is applied to a sheet feed roller through a sheet by connecting a drive side gear to a driven side gear in a rotating direction with a play. CONSTITUTION:If a sheet is pulled by a user, a load is applied to a sheet feed gear, and this load acts on a driven side gear 3B. However, if a load rests on the driven side gear 3B, the load is not positioned on the driven side gear 3A as the drive side gear 3A which engages with a drive gear 1 by rotation given by a coil spring 11 in an initial sheet feed action has a play in a rotating direction between the drive side gear 3A and the driven side gear 3B. Consequently, the drive side gear 3A engages stably with the drive gear 1 only by action of the coil spring 11, if the drive side gear 3A pulls the sheet, and thus the sheet is fed. Stable sheet feed is ensured as the drive side gear 3A is independently actuated and therefore, they can rotate independently at their specified angles.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a type printer, and more particularly to a type printer that performs printing on a type drum having a plurality of type characters formed on its outer peripheral surface.

[Conventional technology]

First, an outline of the conventional type printer mentioned above will be explained with reference to FIGS. 6 and 7.

In FIGS. 6 and 7, a drive gear 1 transmits the drive of a motor (not shown) through a pinion (not shown).
The drive gear 1 is connected to the type drum via a transmission mechanism such as a main gear (not shown) to rotate the type drum. , a gear section 2 is formed that meshes with an intermittent gear section 4 of a control gear 3 for feeding paper.This gear section 2 is a normal gear section with teeth formed all over its circumference. , the intermittent gear section 4 is a gear section in which teeth are partially formed in the circumferential direction.

Further, the control gear 3 is provided with an intermittent gear portion 5 spaced apart from the intermittent gear portion 4 in the axial direction,
This intermittent gear portion 5 is configured to have teeth 6 at only one location a3 in the circumferential direction.

On the other hand, a paper feed gear 7 includes a gear portion 8 that can mesh with the teeth 6.
is arranged adjacent to the control gear 3, and when the paper feed gear 7 rotates in a specific direction, a sheet (not shown) is fed by a rubber roller (not shown) coaxially arranged with the paper feed gear 7. It has become.

A pin 10 is provided protruding from the upper surface of the control gear 3,
One end of a coil spring 11 is fixed to this pin 10 for rotating the control gear 3 counterclockwise and meshing the intermittent gear section 4 of the control gear 3 with the gear section 2 of the drive gear 1. There is. Note that a stopper (not shown) is normally engaged with this pin 10 to restrain rotation of the control gear 3 in the counterclockwise direction. Further, on the outer peripheral surface of the type drum, a plurality of types are arranged so that they can move forward and backward, and after a specific type is faced to the paper, the type is moved forward with a hammer to the front of the type drum. It is now ready to print.

According to the configuration of the conventional device described above, the counterclockwise rotation of the control gear 3 connected to the coil spring 11 is always restrained by the collar, and the specific information to be printed is determined by driving a motor (not shown). The driving gear and the transmission mechanism are rotated at a predetermined angle ( ) so that the printed characters face the paper (not shown) and then stopped, and the printed characters are advanced to the front of the printing drum and pressed against the paper, Printing can be done by transferring ink from type to paper.

When it becomes necessary to feed the paper, such as when the printing of the share is finished, the collar that restrains the counterclockwise rotation of the control gear 3 by the coil spring 11 is moved, and the coil spring 11 Move the control gear 3 counterclockwise,
The intermittent gear portion 4 of the control gear 3 is meshed with the gear portion 2 of the drive gear 1. Then, the clockwise rotation of the drive gear 1 due to the drive of the motor is transmitted to the control gear 3 via the gear section 2 of the drive gear 1 and the intermittent gear section 4 of the control gear 3, and the control gear 3 is driven by the drive gear 1. I will do it.

When the control gear 3 is rotated in the counterclockwise direction in this manner, the rotation of the control gear 3 is transmitted to the paper feed gear 7 via the intermittent gear portion 5 of the control gear 3 and the gear portion 8 of the paper feed gear 7. The paper feed gear 7 follows the control gear 3 to feed the paper.

[Problem to be solved by the invention]

However, in the above-mentioned conventional type printer, during operation, the user feeds the paper by a rubber roller (not shown) disposed coaxially with the paper feed gear 7.
As shown by the arrow in FIG. 6, when the paper is pulled in the opposite direction to the paper feed direction, a load in the same direction acts on the paper feed gear 7, so the control gear is controlled by a stopper (not shown) at the paper feed timing. Even if the constraint of 3 is released, coil spring 1
There was a problem in that the control gear 3 could not be rotated in the opposite direction J1 depending on the urging force of 1, and the paper feeding operation could not be performed.

SUMMARY OF THE INVENTION An object of the present invention is to overcome the problems of the conventional printers described above and to provide a type printer that can reliably feed paper even when a load is applied to the paper feed roller through the paper. .

[Means to solve the problem]

In order to achieve the above-mentioned object, the present invention includes a drive gear driven by a motor, a main gear that transmits the rotational force of the drive gear to a type drum having a plurality of type characters formed on the surface thereof, and a rotation of the drive gear. A control gear that transmits force to the paper feed gear and a transmission switching mechanism that selectively transmits the rotational force of the drive gear to the main gear or the paper feed gear are provided.
In the type printer, an elastic member is provided for biasing the control gear in a direction to mesh with the drive gear, and the control gear is provided with an intermittent gear portion to which rotational force from the drive gear 1n is transmitted. and a driven gear having an intermittent gear portion that meshes with the paper feed gear, and the driving gear and the driven gear are connected with play in the rotation direction. There is.

Further, according to the present invention, the driven gear may include a timing gear that meshes with the drive gear after the paper feed gear rotates.

[For production]

According to the present invention having the above-described configuration, the driving gear and the driven gear that constitute the control gear are connected with play, so that the load of pulling the paper is applied to the driven gear via the paper feed gear. Even if the load is applied, the load does not act on the drive gear. Therefore, at the timing of paper feeding, the drive gear rotates stably due to the action of the elastic member and is reliably connected to the drive gear driven by the motor. They mesh and are driven by the drive gear. As a result, when the drive gear of the control gear rotates by a predetermined angle, there is no play between the drive side gear and the driven side gear, and the drive side gear and the driven side rotate as one, allowing stable paper feeding. .

Furthermore, if a timing gear is formed on the driven gear, after the paper feed gear rotates, the timing gear directly meshes with the drive gear and is driven, thereby making it possible to reliably rotate the driven gear to the initial position.

〔Example〕

The present invention will be explained below with reference to embodiments shown in the drawings. Note that the same reference numerals are used in the drawings to refer to the same or corresponding configurations as those of the conventional structure described above, and the explanation thereof will be omitted.

FIG. 1 shows the main parts of a type printer according to the present invention, in which a yoke 12 is disposed adjacent to a drive gear 1 to which the drive of a motor (not shown) is transmitted, and a yoke 12 is coaxial with the yoke 12. The drive gear 1 is meshed with a disposed gear (not shown). Further, a main gear 13 is meshed with this gear (not shown), so that the rotation of the drive gear 1 is transmitted to the main gear 13. A type drum (not shown) is coaxially arranged on the main gear 13, and a type sheet in which a plurality of type characters are arranged in an Ω shape is wound around the type drum. Additionally, a hammer (not shown) is disposed within the type drum to cause specific characters on the type sheet to protrude. Further, a ratchet wheel 14 is disposed coaxially with the main gear 13, and a claw portion 15 is formed on the outer periphery of the ratchet wheel 14. Roughly, the claw portion 15 also has a pair of large recesses 16, 1 spaced apart in the diametrical direction.
6 is formed.

The electromagnetic plate 17 is coaxially connected to the yoke 12.
It is arranged so as to be rotatable independently from 2. Further, a coil 18 is arranged adjacent to this electromagnetic plate 17, and by energizing this coil 18, the electromagnetic plates 1 to 17 are attracted to the yoke 12, and the rotation of the yoke 12 is transmitted to the electromagnetic plate 17. It is now possible to do so.

Near the electromagnetic plate 17, there is a ratchet 2 at the tip.
A selection lever 19 set to 0 is rotatably supported by a support shaft 21, and a ratchet 20 of one selection lever
can be engaged with the claws 15 of the mouth 1 to the wheel 14, and can also be fitted into the respective recesses 16. Further, the base end of the selection lever 19 faces above the electromagnetic plates 1 to 17, so that the selection lever 19 can rotate following the rotation of the electromagnetic plate 17. Further, an arm 22 is provided protruding from the selection lever 19, and this arm 22 includes the selection lever 19.
One end of a coil spring 23 is connected to the coil spring 23, which urges the selection lever 19 counterclockwise so that the selection lever 19 does not engage or fit into the pawl 15 and recess 16 of the ratchet wheel 14. Furthermore, one of the selection levers is provided with a protruding stopper 24 for restraining the rotation of the control gear 3 due to the coil spring 11, which is an elastic member. part 15, recessed part 16
In the state shown in the first figure, in which the pin 10 is engaged or not fitted, the pin 10 of the control gear 3 is engaged to restrain the counterclockwise rotation of the control gear 3.

FIGS. 2 to 4 show further essential parts of the type printer according to the present invention, and the drive gear 71 has two gear parts 2Δ and 2B vertically spaced apart from each other. The gear parts 2A and 2B are normal gear parts in which teeth are formed all around the circumference.

The control gear 3 that meshes with the drive gear 1 is composed of a drive side gear 3A and a driven side gear 3B, which is a timing gear, which are arranged adjacent to each other in the axial direction so as to be able to approach and separate from each other. Among these, the drive side gear 3A has an intermittent-1 gear part 4 that can mesh with the upper gear part 2A of the drive gear 1.
That's right. Moreover, on the upper surface of the drive side gear 3A,
A pin 10 is provided protrudingly with which the studs 1 to 24 can be engaged, and on the other hand, a pair of pins are provided on the lower surface of the driving gear 3A, one of which is slightly offset in the circumferential direction with respect to the diametrical direction. A protrusion 25.25 is provided in a protruding manner.

The driven gear 3B has a circular outer periphery that fits into any of the recesses 26 formed at intervals in the circumferential direction on the outer periphery of the paper feeding gear 7 to restrain unnecessary rotation of the paper feeding gear 7. It has a section 27. Furthermore, a protrusion 28 is provided above the outer peripheral portion 27, into which both protrusions 25, 25 of the control gear 3 can be fitted. This protrusion 28 is connected to the driven gear 3
An annular center portion 29 arranged concentrically with the center of B
Both protrusions 25 and 25 of the drive side gear 3A are fitted to the outer periphery of this center portion 29, and the drive side gear 3
A and the driven gear 3B can rotate relative to each other. Further, a pair of stoppers 30 and 31 are arranged in a row at intervals in the diametrical direction of the center portion 29, and each projection 25 comes into contact with these studs 1 to 30 and 31 to stop. It has become. On the outer circumferential surface of one of the sleeves 1 to 30, teeth 6 that can mesh with the gear portion 8 of the paper feed gear 7 are provided. A recessed portion 32 is formed by cutting off portion 27.

Further, on the lower surface of the driven gear 3B, the lower surface of the driving gear 1 is provided after the paper feeding gear 7 is rotated by a predetermined angle due to the meshing of the teeth 6 of the driven gear 3B with the gear portion 8 of the paper feeding gear 7. An intermittent gear portion 33 is formed that meshes with the gear portion 2B and prevents the driven gear 3B from rotating to the initial position.

1 Next, the operation of this embodiment having the above-described configuration will be explained. In FIG. 5 for explaining the operation, the gear portion 2A and the gear portion 2B of the driving gear 1, which are arranged coaxially, and the driving side gear 3Δ and the driven side gear 3B of the control gear 3 are explained. For convenience, they are written side by side in the horizontal direction.

First, to explain the printing operation with reference to FIG. 1, the rotation of the drive gear 1 due to the drive of the motor is transmitted to the main gear 13, and the code pattern on the code plate (not shown) disposed on the main gear 13 and the The contact of the contact piece that is in contact with the code pattern generates a pulse signal corresponding to each type character on the type sheet of the type drum coaxial with the main gear 13, so this pulse signal selects a predetermined type character for printing. By energizing the coil 18, the electromagnetic plate 17 is attracted to the yoke 12, which causes the selection lever 19 to rotate clockwise and the ratchet 2
0 engages with a claw portion 15 of a ratchet wheel 14 coaxial with the main gear 13 to restrain rotation of the main gear 13. In this state, the hammer in the type drum operates, and predetermined type can be pressed against the paper to print.

On the other hand, in the paper feeding operation, the electromagnetic plate 1-17 is attracted to the yaw 912 by energizing the coil 18 at a predetermined timing from the state shown in FIG. The ratchet 20 is rotated sharply and the four parts 1 of the ratchet wheel 14
Move to the back of 6.

The rotation of the sharpening main gear 13 is not restricted.

On the other hand, at this time, due to the large rotation of the selection lever 19, its stopper 24 releases the pin 10 of the control gear 3, and as a result, as shown in FIG. 5B, the drive side gear 3 of the control gear 3
A is rotated counterclockwise by the coil spring 11. The energization to the coil 18 is cut off after the pin 10 of the control gear 3 is released, and the radiators 1 to 20 at the tip of one of the selection levers do not restrict the recess 16. However, since the driving gear 3A and the driven gear 3B have play that allows them to rotate at a predetermined angle in the circumferential direction, the driven gear 3B initially remains in a stopped state by itself. Then, as shown in FIG. 5C, at a timing when the biasing force of the coil spring 11 almost disappears, the intermittent gear section 4 starts to mesh with the gear section 2A of the drive gear 1 and transmits the rotation of the drive gear 1. and will continue to rotate in the same direction.

When the aforementioned drive side gear 3A continues to rotate, the drive side gear 3A continues to rotate.
Both protrusions 25, 25 of A engage with both studs 1 to flange 30, 31 of the driven gear 3B, and as shown in the fifth diagram, the driven gear 3B follows the driving gear 3A, and the driven gear 3B follows the driving gear 3A. The teeth 6 of the gear 3B mesh with the gear portion 8 of the paper feed gear 7, and the paper feed gear 7
Rotate.

When the integral rotation of the driving gear 3A and the driven gear 3B continues to a certain extent, and the driving gear 3A returns to its initial position, the teeth of the driving gear 3A as shown in FIG. The portion without the mark faces the gear portion 2Δ of the drive gear 1, and the rotation of the drive gear 1 is no longer transmitted to the drive side gear 3Δ. Then, as shown in FIG.
The rotation of A by the coil spring 11 is restrained.

On the other hand, from just before the state shown in FIG. It will continue to rotate in the direction. Finally, with the driven gear 3B returning to its initial position, the fifth
As shown in Figure G, the driven gear 3B is intermittent -1! A part 3
The toothless portion 3 faces the gear portion 2B of the drive gear 1, and the rotation of the drive gear 1 is no longer transmitted, and the paper feeding operation ends.

By the way, when the user pulls the paper during paper feeding operation, a load is applied to the paper feeding gear 7, and this load is transferred to the driven gear 3B.
However, the drive side gear 3A, which is rotated by the coil spring 11 and meshes with the drive gear 1 at the beginning of the paper feeding operation,
Since there is play in the rotational direction between the driven gears 3B, even if a load is applied to the driven gear 3B, this load is not placed on the drive gear 3A. Therefore, drive side gear 3
Even when the paper is pulled, Δ is stably engaged with the drive gear 1 by the action of the coil spring 11 alone, and the paper can be fed.

According to this embodiment, the drive side gear 3A and the driven side gear 3B are separated and can rotate independently by a predetermined angle, so that the paper feeding operation can be performed stably.

Note that the present invention is not limited to the embodiments described above, and various changes can be made as necessary.

〔Effect of the invention〕

As explained above, according to the present invention, even if a load is applied from the paper to the paper feed roller, this load acts only on the driven gear and is not transmitted to the driving gear, so the driving gear is moved by the elastic member. It is rotated stably and engaged with the drive gear, so that the paper feeding operation can be performed stably.

6

[Brief explanation of drawings]

1 to 5 show an embodiment of a type printer according to the present invention, FIG. 1 is a plan view of the main part, and FIGS. 2 Δ and B are plan views of further main parts of FIG. 1. diagram and front view,
Figure 3 is an exploded perspective view of the main parts of Figure 1, Figure 4 is each gear) 1
FIGS. 5A to 5G are exploded explanatory views showing the operation of this embodiment. FIGS. 6 and 7 are a plan view and an exploded perspective view of a conventional type printer. 1... Drive gear, 3△... Drive side gear, 3B...
Driven side gear, 7...Paper feed 1 gear, 11...Coil spring, 12...Yoke, 13...Main gear, 1/
I...love'')~wheel, 17...electromagnetic plate, 18...coil, 19...selection lever 20.
...To Radi Jtsu 1, 23...Coil spring, 24...
Stopper, 25.28...protrusion.

Claims (1)

[Scope of Claims] 1) A drive gear driven by a motor, a main gear that transmits the rotational force of the drive gear to a type drum having a plurality of type characters formed on its surface, and a main gear that transmits the rotational force of the drive gear to a type drum having a plurality of type characters formed on its surface. In a type printer provided with a control gear that transmits to a feed gear and a transmission switching mechanism that selectively transmits rotational force of the drive gear to the main gear or the paper feed gear, the control gear is meshed with the drive gear. an elastic member that biases the control gear in a direction in which the control gear is rotated; What is claimed is: 1. A type printer comprising a driven gear and a driven gear, the driving gear and the driven gear being connected with play in the rotational direction. 2) The type printer according to claim 1, wherein the driven gear is provided with a timing gear that meshes with the drive gear after rotation of the paper feed gear.