JPH0336076A - Ink ribbon change-over mechanism - Google Patents

Abstract

PURPOSE:To realize an inexpensive lightweight serial printer having reliability holding an ink ribbon cartridge receiving a multicolor ink ribbon by providing the first and second drive gears each having an one-way clutch feeding an ink ribbon by the rotary driving of a stepping motor built therein. CONSTITUTION:When the motor gear 10 of a stepping motor 9 is rotated in the direction shown by an arrow(d), the gear 11 meshed with the motor gear 10 is rotated in the direction shown by an arrow (e) and a feed shaft 12 is rotated in the direction shown by an arrow (f) and ribbon feed operation is performed by a torque piece 13. Next, when the motor gear 10 is rotated in the direction shown by an arrow D, the one-way clutch built in the gear 11 becomes an open state and the feed shaft 12 becomes regardless of the rotation of the gear 11 to perform no rotary operation. The gear 16 having the one-way clutch meshed with the gear 11 built therein is rotated in the direction shown by an arrow F to rotate the surface cam 18 fixed to the leading end of a change shaft. By controlling the quantity of rotation of the stepping motor 9 at the time of the change-over of the ribbon, the surface cam 18 is rotated to a predetermined position and a ribbon cartridge 2 is shaken by necessary quantity to allow the position of a multicolor ribbon 1 to correspond to a printing head 5.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an ink ribbon switching mechanism, and particularly to a bearing member in which a ribbon cartridge containing multicolored ink ribbons is installed in a carrier frame in a serial printer. The present invention relates to an ink ribbon switching register structure for a serial printer, which is detachably attached to an ink ribbon cartridge and configured so that the printing color can be switched to a specified color by the swinging movement of an ink ribbon cartridge.

[Conventional technology]

The ink ribbon mounting means for serial printers, which are used as output devices for personal computers and word processor zero information processing systems, is to mount the ink ribbon directly on the main frame of the printer and stretch the ink ribbon over the entire printing width, and to There are two methods in which the carrier on which the print head is mounted performs printing while making left and right spacing movements, and another method in which the print head is mounted on the carrier and is integrated with the print head and performs left and right spacing movements. Two types of methods are used:

In recent years, color CRT display devices capable of displaying multiple colors have been increasingly used as display devices for information processing systems, and with this, it has become desirable to be able to print output in multiple colors. It has become.

In order to satisfy these demands, the same ink ribbon is divided into two or more layers vertically, each layer is colored in a different color, and a multi-colored ink ribbon is used. Printers have come into widespread use.

[Problem to be solved by the invention]

Therefore, it is necessary to provide both an ink ribbon feeding drive unit and an ink ribbon switching drive on the carrier.
This method has drawbacks such as increased manufacturing cost and carrier weight, making it unsuitable for high-speed printing.

[Means to solve the problem]

The present invention provides an ink ribbon switching mechanism for a serial printer that minimizes the increase in carrier weight by transferring a stepping motor for driving the ribbon feeding to the ink ribbon switching drive, and is low cost and highly reliable.

An ink ribbon for a serial printer that is swingably held by a carrier frame on both ends of an ink ribbon cartridge that accommodates multicolor ink ribbons of two or more colors, and that detachably holds an ink ribbon cartridge cartridge that has a cam follower on at least the bottom surface. A switching mechanism,
A first drive gear for feeding the ink ribbon, which is attached to the carrier frame and has a built-in one-way clutch that feeds the ink ribbon by rotational driving of a stepping motor in one direction, and a one-way gear that meshes with the first drive gear. The second drive gear has a built-in clutch and an ink ribbon switching cam fixed on a shaft to engage with a cam follower of the ink ribbon cartridge, so that the ink ribbon switching cam does not rotate during the ribbon feeding operation.

〔Example〕

Next, the present invention will be explained in detail with reference to the drawings.

An embodiment of the present invention is shown in a perspective view in FIG. 1. Referring to FIG. Shafts 3a and 3b are provided and hexagram b1 carrier 4
It is rotatably held by holding parts 4a and 4b formed in a part of the holder.

The carrier 4 carrying the ink ribbon cartridge 2 and the print head 5 is reciprocated from side to side while performing a printing operation along the sliding platen 8 by means of a guide shaft 6.7.

A stepping motor 9 for feeding the ribbon and driving ribbon switching is fixed to the carrier 4, and a motor gear 10 is fixed to the stepping motor shaft 9a. A feed shaft 12 to which a torque piece 13 is fixed for transmitting rotation to a ribbon feed roller (not shown) inside the ink ribbon cartridge 2 is installed correspondingly to the gear 11 that meshes with the motor gear 10 and has a built-in one-way clutch. I'm so happy! 7. The opposite end of the trike piece 13 is rotatably held by a bearing bush 14 embedded in the carrier 4, and is prevented from being removed by a retaining ring 15.

Further, a gear 16 having a built-in one-way clutch is meshed with the gear 1 for the purpose of transmitting the drive for ribbon switching. A change shaft 17 to which a cylindrical surface cam 18 corresponding to the cam 7 follower 19 provided on the bottom of the ink ribbon cartridge 2 is fixed is installed in correspondence with the gear 16. The other end of the change shaft is connected to the carrier 4. A retaining ring 1 is rotatably held in a bearing bush 14 buried in the
5, the structure is designed to prevent removal.

Furthermore, a bias spring 20 is fixed on the carrier 4 to keep the cam follower 19 on the bottom of the ink ribbon cartridge 2 in constant contact with the surface cam 18. i
The tip of the bias spring 20 is in contact with the bottom surface of the ink ribbon cartridge 2.

Next, the operation of this mechanism will be explained with reference to FIGS. 4 1 and c-c' arrow views in FIG.
When the gear 11 rotates in the direction of the arrow f, the gear 11 with a built-in one-way clutch that engages with the motor gear 10 rotates in the direction of the arrow e. At this time, the one-way clutch built in the gear 11 rotates the feed shaft 12 in the direction of the arrow f, thereby Torque piece 13 fixed to the tip of shift feed shaft 12
Then perform the cylinder feeding operation. Also, in this state, gear 11
The gear 16, which has a built-in fun-way clutch that meshes with the gear 16, rotates in the direction of the arrow g, and is independent of the rotation of the fd gear 16.

Next, when the motor gear 10 rotates in the direction of the arrow, the gear 1 with a built-in one-way clutch that engages with the motor gear 10
1 rotates in the direction of arrow E, and the Funway clutch built into the gear 11 is in an open state, so that the feed shaft 12 does not perform any rotation operation unrelated to the rotation of the gear 11.

The gear 16 with a built-in one-way clutch that meshes with the gear 11 rotates in the direction of arrow F in the case of the housing, and the one-way clutch built in the gear 16 rotates the change shaft 17 in the direction of arrow G, thereby causing the change shaft to rotate in the direction of arrow G. The surface cam 18 fixed to the tip is rotated.

In addition, by controlling the amount of rotation of the stepping motor 9 when switching the ribbon, the surface cam 18 is rotated to a predetermined position, the ribbon cartridge 2 is swung by a necessary amount, and the position of the multicolor ribbon 1 is made to correspond to the printing hect 5.

〔Effect of the invention〕

As explained above, the present invention uses a configuration using one stepping motor and two drive gears with built-in one-way clutches, thereby providing a low-cost, lightweight, and highly reliable serial printer ribbon switching mechanism. There is an effect.

[Brief explanation of drawings]

FIG. 1 is a perspective view of an embodiment of the present invention, FIG. 2 is a view taken along the line AA' in FIG. 1, FIG. 3 is a view taken along line BB' in FIG. 1, and FIG. FIG. 5 is a schematic view taken along line Y-Y' in FIG. 1, and FIG. 5 is a view taken along line c-c' in FIG. l...Multicolor ink ribbon, 2...Ink ribbon cartridge, 3a, 3b...Support shaft, 4...Carrier, 4a, 4b... ...Holding section, 5...Print head, 6.7...
Guide shaft, 8...Platen, 9...
...Stepping motor, 9a...Motor shaft,
lO...Motor gear, 11...Gear,
12...Feed shaft, 13...
Torque piece, 14...Bearing bouche, 15.
...Retaining ring, 16...Gear, 17...
...Change shaft, 18...Break cam, 1
9...Cam follower, 20...Bias spring.

Claims (1)

[Claims] In impact type serial printers, the print head and ink ribbon cartridge are mounted on a carrier and perform printing operations while reciprocating along the printing surface.
An ink ribbon switching mechanism for a serial printer that removably holds an ink ribbon cartridge that is swingably held by a carrier frame on both sides of an ink ribbon cartridge that accommodates ink ribbons of more than one color, and that has a cam follower on at least a bottom surface. a first drive gear for feeding the ink ribbon, which is attached to the carrier frame and has a one-way clutch that feeds the ink ribbon by rotational driving of a stepping motor in one direction; and a first drive gear that meshes with the first drive gear. It has a one-way clutch, and is composed of a second drive gear fixed on a shaft, and an ink ribbon switching cam that engages with a cam follower of the ink ribbon cartridge, and when the stepping motor is rotationally driven in one direction, the ink ribbon is The ink ribbon switching cam rotates only when the stepping motor is rotated in the opposite direction to the above state, and the ink ribbon lift operation is performed by the vertical movement of the cam follower of the ink ribbon cartridge. An ink ribbon switching mechanism characterized by: