JPH0343286A - Carriage mechanism - Google Patents

Abstract

PURPOSE:To reduce the extra run of a ribbon cloth by providing a a ribbon cloth running power transmission gear, a drive force transmission gear, a planetary gear as well as an energization spring on the side of one drive force transmission gear with the planetary gear ie engaged when a carriage moves in a non-printing direction and a disengagement mechanism. CONSTITUTION:A spring 13 which engages a drive force transmission gear 5b with a drive force transmission gear 5a by moving the gear 5b upward and a disengagement mechanism 22 which forces the drive force transmission gear 5b in a direction where it is disengaged with the drive force transmission gear 5a during the movement of a carriage in a non-printing direction are provided on the side of the drive force transmission gear 5b with which a planetary gear 4 is engaged during the movement of the carriage in a non-printing direction. While the carriage has moved to the left, the planetary gear 4 moves to the right by drive force of a rack 3 and becomes engaged with the drive force transmission gear 5, rotating counter-clockwise, Then the drive force transmission gear 5b rotates around a clock. However, a ribbon cloth running force transmission gear 1 which engages with the drive force transmission gear 5a,and the drive force transmission gear 5a are not driven as the drive force transmission gear 5a is not engaged with the drive force transmission gear 5b.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a carriage mechanism, and particularly to a carriage mechanism of a printer device used as an output device of an information processing device.

[Prior Art] Conventionally, in the carriage mechanism of this type of printer device, a print head and an ink ribbon cassette are mounted on a carriage that reciprocates along the axial direction of a platen.
a ribbon cloth running force transmission gear that engages with the take-up shaft of the ink ribbon cassette; a pair of driving force transmission gears that mesh with each other, one of which meshes with the ribbon cloth running force transmission gear; A planetary gear is provided which meshes with the ring fixed to the housing and switches to mesh with one of the driving force transmission gears depending on the direction of movement of the carriage.

When the carriage moves left and right along the printing surface by the drive source motor, power is obtained from the front of the carriage and the rack that supports the vertical movement, and the planetary gear moves in the opposite direction of the carriage movement. Provides driving force to the driving force transmission gear. In this case, even when the carriage moves left or right, the running force is transmitted to the ribbon cloth of the ink ribbon cassette via the ribbon cloth running force transmission gear, so that it always rotates in a fixed direction in response to the movement of the carriage. was.

[Problems to be Solved by the Invention] In the conventional carriage mechanism described above, in the case of unidirectional printing, the ribbon cloth running force transmission gear rotates in a constant direction even when the carriage is moving in the non-printing direction. However, this rotation resulted in wasteful consumption of ribbon cloth.

In addition, when the ribbon cloth is running, ink is constantly supplied to the ribbon cloth, or when using an inking type ink ribbon cassette, the amount of ink on the ribbon cloth in the skipped portion when the carriage moves in the non-printing direction during unidirectional printing. When printing is performed, there is a difference in the amount of ink on the ribbon cloth where the ink has been transferred to the printing surface, and if printing is performed again across both ribbon cloths with different ink amounts, uneven shading may occur. There was a drawback that this occurred.

[Means for Solving the Problems] The present invention has been made to solve the above problems, and as a means for solving the problems, the present invention includes a print head and an ink ribbon cassette, and a print head and an ink ribbon cassette that are mounted in a reciprocating manner along the axial direction of the platen. A ribbon cloth running force transmission gear that engages with the take-up shaft of the ink ribbon cassette, a pair of mutually meshed driving force transmission gears, one of which meshes with the ribbon cloth running force transmission gear, and the carriage that moves. and a planetary gear that meshes with a rack fixed to the housing along the moving direction of the carriage and switches to mesh with one of the driving force transmission gears depending on the moving direction of the carriage, and one of the pair of driving force transmission gears in the non-printing direction. One of the driving force transmission gears with which the planetary gear meshes during movement is provided with a spring that biases this driving force transmission gear in the direction of meshing with the other driving force transmission gear, and a spring that biases the driving force transmission gear in the direction of meshing with the other driving force transmission gear when the planetary gear is moved in the non-printing direction. The driving force transmitting gear is configured to include a disengaging mechanism that presses the driving force transmitting gear in the direction of disengaging the driving force transmitting gear from the other driving force transmitting gear.

[Example] FIG. 1 is an external perspective view of an embodiment of the present invention.

In the figure, reference numeral 2 denotes a carriage, on which a printing pad 8 and an ink ribbon cassette 6 are mounted. This carriage 2 is supported by a guide shaft 20 and a rack 3 fixed to the housing, and is connected to a platen (bell) 21 by a platen (bell) 21.
(not shown), it can reciprocate along its axial direction.

Further, on the carriage 2, there is a ribbon cloth running force transmission gear l that engages with the take-up shaft of the ink ribbon cassette 6, and a pair of mutually meshed driving force transmission gears, one of which meshes with the ribbon cloth running force transmission gear 1. 5a, 5b, and a planetary gear 4 which is selectively engaged with one of the driving force transmission gears 5a, 5b depending on the moving direction of the carriage 2.

The ribbon cloth running force transmission gear 1 receives power from the rack 3 when the carriage 2 moves left and right, and is rotatable in only one direction by the action of the planetary gear 4 and the driving force transmission gears 5a and 5b. The rotation of the ribbon cloth running force transmission gear 1 serves as a driving source for running the ribbon cloth 7 of the ink ribbon cassette 6.

The planetary gear 4 is supported by the planetary gear arm 14, and can swing toward the driving force transmission gear 5a or 5b. By meshing this planetary gear 4 with the rack 3,
When the carriage 2 moves in the printing direction, the driving force transmission gear 5a
When moving in the non-printing direction, it meshes with the driving force transmission gear 5b.

Of the pair of driving force transmitting gears 5a and 5b, the driving force transmitting gear 5b is engaged with the planetary gear 4 during movement in the non-printing direction. A spring 13 for meshing and a mesh release mechanism 22 for pressing the driving force transmission gear 5b in the meshing release direction with respect to the driving force transmission gear 5a when moving in the non-printing direction are provided.

The disengagement mechanism 22 includes a rotatably supported integral cam 12 and a permanent magnet 11, and a coil 10 that is energized and de-energized by a switch 9 and operates the cam 12 via the permanent magnet 11.

2 and 3 are cross-sectional views of the inside of the carriage viewed from the rack 3 side.

FIG. 2 shows a case of bidirectional printing in which printing is possible when the carriage 2 moves in both left and right directions. In this state, when the switch 9 is turned OFF, no magnetic force is generated in the coil 10 as shown in FIG. It is lifted upward by the force of , and engages with the driving force transmission gear 5a.

4 and 5 are cross-sectional views of the interior of the carriage viewed from above during bidirectional printing.

FIG. 4 shows a state in which the carriage is moving in the direction of the arrow. The planetary gear 4 receives driving force from the rack 3, moves to the left, and rotates clockwise to connect with the driving force transmission gear 5a. They will intertwine. As a result, the driving force transmitting gear 5a rotates counterclockwise, and the ribbon cloth running force transmitting gear 1 meshing with the driving force transmitting gear 5a rotates clockwise.

Figure 5 shows the carriage moving to the left as shown by the arrow.The planetary gear 4 receives driving force from the rack 3, moves to the right, and transmits the driving force while rotating counterclockwise. meshes with gear 5b, thereby driving force transmission gear 5b
The driving force transmitting gear 5a that meshes with the driving force transmitting gear 5b rotates counterclockwise, and the ribbon cloth running force transmitting gear l that meshes with the driving force transmitting gear 5a rotates clockwise.

As shown in FIGS. 4 and 5, when the carriage moves in both left and right directions, the ribbon cloth running force transmission gear 1 obtains clockwise rotation and gives the ribbon cloth 7 running in a fixed direction.

FIG. 3 shows a case of unidirectional printing in which printing is possible only when the carriage moves in the right direction. In this state, when the switch 9 is turned on, magnetic force is generated in the coil 10, which attracts the S pole of the permanent magnet 11, and the cam connected thereto rotates clockwise, causing the driving force transmission gear 5 to rotate.
This will push down b.

FIGS. 6 and 7 are views of the inside of the carriage viewed from above during unidirectional printing.

FIG. 6 is a diagram when the carriage is moving in the direction of the arrow, and the planetary gear 4 receives driving force from the rack 3, moves to the left, and rotates clockwise while transmitting the driving force. The ribbon cloth running force transmission gear 1 meshing with 5a obtains clockwise rotation.

Figure 7 is a diagram when the carriage is moving to the left as indicated by the arrow, and the planetary gear 4 receives driving force from the rack 3 to move to the right and is driven while rotating counterclockwise. meshes with the force transmission gear 5b, thereby the driving force transmission gear 5
b rotates clockwise. However, as shown in FIG. 3, the driving force transmitting gear 5a and the driving force transmitting gear 5b do not mesh with each other, so the driving force transmitting gear 5a and the ribbon cloth running force transmitting gear 1 that meshes with the driving force transmitting gear 5a do not obtain a driving force. .

[Effects of the Invention] As explained above, in the carriage mechanism of the present invention, one of the driving force transmitting gears, which is engaged with the planetary gear during movement in the non-printing direction, has a drive force transmitting gear. a spring that urges the gear in the direction of engagement with the other driving force transmission gear; and a disengagement mechanism that presses the one driving force transmission gear in the direction of disengaging the other driving force transmission gear when moving in the non-printing direction. Therefore, when performing unidirectional printing, unnecessary running of the ribbon cloth is reduced by not applying driving force to the ribbon cloth running force transmission gear only when the carriage moves in the direction where printing is not performed. There is an effect that can be done.

[Brief explanation of drawings]

FIG. 1 is an external perspective view showing an embodiment of the present invention, and FIGS. 2 and 3 are cross-sectional views of the inside of the carriage when printing in both directions, viewed from the rack side. FIGS. 4 and 5 are cross-sectional views of the interior of the carriage viewed from above in the states shown in FIGS. 2 and 3, respectively. 6 and 7 are cross-sectional views of the inside of the carriage viewed from above during unidirectional printing, respectively. 1: Ribbon cloth running force transmission gear 2: Carriage 3 Neck 4: Planetary gears 5a, 5b = Driving force transmission gear 6: Ink ribbon cassette 8: Print head 13: Spring 22: Engagement release mechanism

Claims (1)

[Claims] A carriage carrying the print head and the ink ribbon cassette and reciprocating along the axial direction of the platen includes a ribbon cloth running force transmission gear that engages with the winding shaft of the ink ribbon cassette; A pair of mutually meshed driving force transmission gears, one of which meshes with the other, and a planet that meshes with a rack fixed to the housing along the moving direction of the carriage and is switched to mesh with one of the driving force transmission gears depending on the moving direction of the carriage. One of the pair of driving force transmitting gears, with which the planetary gear meshes when moving in the non-printing direction, has a gear that meshes with the other driving force transmitting gear. A carriage mechanism comprising: a spring that biases the carriage in the non-printing direction; and a disengagement mechanism that presses the one drive force transmission gear in the direction of disengagement with the other drive force transmission gear when moving in the non-printing direction.