JPH061421Y2 - Printer color ribbon idle feed mechanism - Google Patents

Description

[Detailed description of the device] [Industrial applications]

The present invention relates to a color ribbon idling mechanism of a thermal transfer printer.

[Prior art]

When feeding the specified color to the beginning of the color ribbon based on the print data, the conventional thermal transfer printer uses the power to reciprocate the carriage equipped with the thermal head to wind the ribbon or the carriage. In some cases, a capstan and pinch roller dedicated to idle feeding were installed in the part to wind them with a motor.

[Problems and means to be solved by the device]

In the former method, the carriage must be reciprocated when selecting the specified color when using the color ink ribbon, and this movement is because the thermal head is in pressure contact with the ink ribbon, so that stains etc. adhere to the paper. There is a problem causing it. In the latter method, the ink ribbon must be removed from the capstan each time the cartridge is replaced, and the capstan must be rotated in synchronization with the printing speed in order to rotate the capstan. There are problems such as. An object of the present invention is to eliminate the above-mentioned conventional drawbacks, and a ribbon idling mechanism of a printer that is driven by a capstan driven by a motor provided inside a carriage and a pinch roller provided in a guide frame to remove the ribbon. To provide.

【Example】

FIG. 1 shows an embodiment of a thermal transfer printer according to the present invention, FIG. 1 is a perspective view of a main portion, and FIGS. 2 to 4 are partially enlarged views of a pinch roller portion. The embodiment will be described in detail below with reference to FIG. In FIG. 1, reference numeral 1 is a thermal head, 19 is a heat dissipation plate that rotatably supports a thermal head shaft 21, and a shaft 2
1 is fixed to the carriage frame 20. The carriage frame 20 is supported by the guide shaft 16, and the arrow E
It is arranged so as to be capable of reciprocating in the E1 and E2 directions. An ink ribbon take-up core 24 and a feed core 24 ′ are arranged on the carriage frame 20. After the take-up core 24 rotates and the ink ribbon 25 of the ribbon cassette 26 passes through the thermal head 1, the ink ribbon 25 is taken up by the spool in the ribbon cassette 26. 42 is a capstan for ribbon feeding only. A detection plate 43 for the home position sensor is arranged below the carriage frame 20, and is fixed to the home position sensor 44 on the bottom plate of the guide frame 51. The home position sensor 44 detects the detection plate 43. The guide frame 5 on one wall for fixing the guide shaft 16
A pinch roller 60 is arranged at position 1. The pinch roller 60 rotates around a shaft 60 'and is fixed to a pinch roller mounting plate 61. Pinch roller mounting plate 61
Is supported by a spring support shaft 62. A spring bearing 66, a spring 65, and a washer 64 are attached to the spring support shaft 62 and fixed by an E ring 63. The pinch roller mounting plate 61 indirectly connects to the spring support shaft 62.
Are arranged so as to be movable in the directions of arrows F1 and F2. FIG. 2 is an enlarged view of the pinch roller portion.
6, a pinch roller mounting plate 61 is pivotally supported. In FIG. 3, the carriage 20 moves in the direction of arrow E1 and the ink ribbon 25 is pressed against the pinch roller 60 by the capstan 42. FIG. 4 is an enlarged plan view of the pinch roller 60, the ink ribbon 25, and the capstan 42. The capstan 42 is rotated in the H direction by a drive source provided inside the carriage 20, and the ink ribbon 25 is wound around the spool in the ribbon cassette by the winding core 24. The capstan 42 and the pinch roller 42 form a ribbon winding mechanism. FIG. 5 shows the inside of the carriage portion of the serial thermal transfer printer. Reference numeral 4 denotes a motor installed under the carriage frame, and a motor gear 8 is fixed to a motor shaft 4a penetrating the carriage frame 20. A sun gear 9 is meshed with the motor gear 8. The sun gear 9 has a planetary gear 11. Reference numeral 31 is a pin fixed to the carriage frame 20, and a support arm 10 that supports the sun gear 9 and the planetary gear 11 is rotatably mounted about this pin. The planetary gear 11 can rotate around an axis provided upright on the support arm 10. Reference numerals 12 and 13 denote intermediate gears that transmit the rotation of the planetary gear 11 to the winding gear 14 engaged with the ink ribbon winding core 24. Further, the transmission gear 40 transmits the rotation of the winding gear 14 to the capstan gear 41 engaged with the capstan 42. Reference numeral 3 denotes a cam for rocking the thermal head, which can rotate 360 degrees about the shaft 3a. This cam 3 has at least three cam positions r1, r2, r3 with different radii to the outer circumference. There is. The cam gear 7 fixed to the shaft 3a is transmitted to the planetary gear 11 by the rotation of the sun gear 9. A reflective portion 6 is installed on the upper surface of the cam 3, and the rotational position of the cam 3 is detected by the reflective photosensor 5. A spring support member 18 is in contact with the outer periphery of the upper portion of the cam 3. The compression coil spring 2 is supported by the spring support member 18,
When the cam position r2 that indirectly engages with the cam 3 and the cam position r2 having the largest radius of the cam 3 engages with the spring support member 18, the thermal head 1 is urged from behind by the arrow G1 toward the platen 17 to receive the pressure contact force. In the plan view of FIG. 6, the winding core 24 on the carriage frame 20 is engaged with the gear 14. The capstan 42 is engaged with the gear 41. Further, a feeding core 24 'is provided. FIG. 7 is a block diagram of a thermal transfer printer according to the present invention. The operation of the thermal transfer printer according to the present invention is as follows:
When input to the CPU 30 from the interface 39,
First, the first motor drive circuit 33 is operated to operate the motor 4
Is rotated in the direction of arrow A2, the rotation of the sun gear 9 is further transmitted to the planetary gear 11 and the cam gear 7, the cam 3 is rotated, and the thermal head 1 is moved to the platen 17 side and brought into pressure contact therewith. When the reflective photosensor 5 detects that the thermal head 1 is pressed against the platen 17, the motor 4 reverses to the arrow A1, but the planetary gear 11 is disengaged from the cam gear 7, so the cam 3 stops and the thermal head 1 Maintain pressure contact. The rotation transmitted to the planetary gear 11 from the sun gear 9 due to the rotation of the motor 4 toward the arrow A1 side is the intermediate gears 12 and 13.
Is transmitted to the gear 14 which is integral with the winding core 24, and the winding operation of the ribbon is started. At this time, at the same time, the second motor drive circuit 38 drives the carriage motor 37 to print while moving the carriage frame 20 in the column direction E2. At this time, since the capstan 42 shown in FIG. 1 is separated from the ink ribbon 25, the driving force of the ink ribbon 25 due to the contact between the pinch roller 60 and the capstan 42 is not generated. When the printing operation is completed, the motor 4 again rotates in the direction of arrow A1 and the cam 3 rotates. The spring support member 18 comes into contact with the r1 cam position where the turning radius is small, and the thermal head 1 is separated from the platen 17. At this time, the reflective photosensor 5 simultaneously detects the position and the motor 4 stops. The carriage motor 37 is driven to move the carriage 20 in the E1 direction to the home position of the print start position and return it. The home position is detected by the home position sensor 44 shown in FIG. By the way, since the color ribbon has a plurality of inks sequentially arranged, the print data input to the CPU 30 includes a signal for designating a color to be printed. The present invention, when the ink ribbon 25 and the carriage frame 20 operate, the ink ribbon 2 of the ink ribbon cassette 26
5 is jump-fed to the beginning of the designated color. The carriage frame 20 is further moved in the E1 direction by a predetermined number of steps from the home position position by the rotation of the carriage motor 37. As a result, the ink ribbon 25 is sandwiched between the capstan 42 and the pinch roller 60 as shown in FIG. Further, the pinch roller 60 is pushed by the capstan 42 and moves in the F1 direction, and the pinch roller mounting plate 61 compresses the spring 65 provided on the spring support shaft 62. This makes the pinch roller 60
Causes a repulsive force in the F2 direction, so the ink ribbon 2
5 is securely pressed against the capstan 42. The home position sensor 44 detects the position of the carriage frame 20 at this time, and the first position is detected by the detection signal.
The motor drive circuit is driven to rotate the motor 4 in the A1 direction, whereby the winding core 24 rotates, and at the same time, the capstan 42 rotates in the H direction. As a result, the ink ribbon 25 sandwiched between the capstan 42 and the pinch roller is wound up on the spool in the ink ribbon cassette 26. After completing the idling to the designated color, the carriage motor 37 drives for a predetermined number of steps to move the carriage frame 20 in the E2 direction and return it to the home position. At that time, the capstan 42 separates from the pinch roller 60. On the other hand, the spring 65 that has been compressed by the pinch roller mounting plate 61 also returns to its original position because the pinch roller mounting plate 61 has moved in the F2 direction. Further, when the pinch roller 60 separates from the capstan 42, the ink ribbon 25 also separates from the capstan 42. The idling speed of the ink ribbon 25 is determined by the gear ratio between the take-up gear 14 and the capstan gear 41 shown in FIG. The ink ribbon 25 pulled out at a high speed by the capstan 42 can be wound up by the winding core 24 rotating at a high speed. Since the winding core 24 is provided with a slip mechanism (not shown), the ink ribbon 25 There is no unreasonable tension. When the print signal is input to the interface 39, the carriage 20 stops at the home position.

[Effect of device]

Since a predetermined color of the color ink ribbon can be cued at high speed in a standby state before the start of printing, it is advantageous for increasing the speed of the color thermal transfer printer without depending on a large movement of the carriage frame. Further, since the same drive source as the head pressure contact / release and ribbon winding mechanism is used, the cost can be kept low and the structure is simple. Further printing operation,
Since the ink ribbon is separated from the capstan 42, even if the capstan 42 rotates at a high speed, the printing paper will not be soiled, and wrinkles due to excessive tension will not deteriorate print quality. Further, since the ink ribbon 25 stops at the home position at the end of printing, the capstan 42 and the pinch roller 60 are separated,
At the time of stop, the ink ribbon cassette 26 can be easily attached / detached, which is good in terms of operability, and has a great effect on simplification and cost reduction.

[Brief description of drawings]

1 to 4 are schematic views showing an embodiment of a thermal transfer printer according to the present invention. FIG. 1 is a perspective view, FIGS. 2 to 4 are partially enlarged views of a capstan and a pinch roller, and FIG. Is a plan view of the inside of the carriage, FIG. 6 is a plan view of the carriage portion, and FIG. 7 is a schematic view showing the construction of the thermal transfer printer according to the present invention. 1 ... Thermal head 16 ... Guide shaft 20 ... Carriage frame 25 ... Ink ribbon 42 ... Capstan 51 ... Guide frame 60 ... Pinch roller.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Kusadaira 1-4 Fujimi-cho, Gyoda-shi, Saitama Prefecture 1 Jeco Co., Ltd. (72) Toru Iwasa 1-4-1 Fujimi-cho, Gyoda-shi, Saitama 1 Jeco Co., Ltd. (72) Creator Masao Masumura 1-4-4 Fujimi-cho, Gyoda City, Saitama Prefecture

Claims (1)

[Scope of utility model registration request] 1. A thermal head having a heating element arranged thereon is pressed against a platen arranged to face the thermal head and moved to transfer the ink of an ink ribbon provided between the thermal head and the platen onto a recording paper. In a thermal transfer printer, a carriage is provided with a thermal head having a capstan that drives the ink ribbon using a motor as a drive source, and a pinch roller provided on a guide frame. The pinch roller and the capstan are brought into pressure contact with each other to form a color ribbon. A color ribbon idling mechanism for a printer characterized by idling.