JPH0924652A - Cassette - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make a mechanism of a printer body simple by providing a bobbin, which can be mounted on or dismounted from a cassette body without removing a tension adjusting unit from the cassette body, and engaging the bobbin with the tension adjusting unit while the bobbin is mounted on the cassette body. SOLUTION: A slide actuating brake is used for a tension adjusting unit 13 of a feed side bobbin 11. When the feed side bobbin 11 applies a turning torque of at least a specified magnitude to a rotating shaft of an actuating brake, which engages with the feed side bobbin 11, the rotating shaft of the slide actuating brake rotates with the feed side bobbin 11 to adjust a back tension to make the sme constant. Further, a slide actuating clutch is used for a tension control unit 14 of a take-up side bobbin 12. If a turning torque acting between a rotating shaft of an actuating clutch and a rotating shaft on a driving side of a printer body is at most a specified value, a rotating shaft on a driving side of the slide actuating clutch and a rotating shaft of the take-up side bobbin 12 rotate without sliding.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermal transfer sheet cassette used in a printer for thermal transfer recording.

[0002]

2. Description of the Related Art Conventionally, a thermal transfer sheet having a color material layer provided on one surface of a base sheet and an image receiving sheet having an image receiving layer as needed are provided with a heating device such as a thermal head and a platen. It is pressed against the roller and selectively heats the heat generation part of the heating device according to the image information, and transfers the color material contained in the color material layer on the thermal transfer sheet to the image receiving sheet to record an image. Various methods have been proposed. Among them, the heat-sensitive melting transfer method and the heat-sensitive sublimation transfer method are widely used.

The former heat-sensitive melt transfer method is a thermal transfer sheet in which a base material sheet such as a plastic film has a base sheet such as a plastic film carrying a heat-melting ink layer in which a coloring material such as a pigment is dispersed in a binder such as a wax or a resin having a heat-melting property. It is an image forming method in which a coloring material is transferred together with a binder onto an image receiving sheet such as paper or a plastic sheet by applying energy according to image information of a heating device such as a thermal head. On the other hand, the latter thermal sublimation transfer method is a thermal transfer sheet in which a dye layer in which a sublimable dye used as a coloring material is dissolved or dispersed in a binder resin is carried on a base material sheet such as a plastic film, and paper or a plastic sheet. By using an image receiving sheet provided with an image receiving layer on a support, by applying energy according to the image information of a heating device such as a thermal head, the sublimable dye contained in the dye layer on the thermal transfer sheet It is a method of recording an image by transferring it to an image receiving layer on a transfer target.

The printing mechanism of the printer adopting the above-mentioned image forming system is as shown in FIG. 1, and the thermal transfer sheet 1 and the image receiving sheet 2 are passed between the platen roller 3 and the thermal head 4 in a pressure contact state. Thermal head 4
An image is recorded on the image receiving sheet 2 by selectively applying heat. Here, the thermal transfer sheet 1
The one used is that which is unwound from the supply side bobbin 5 and wound around the winding side bobbin 6, and both bobbins 5 and 6 are housed in a cassette case in order to facilitate mounting on the printer. Is also used. Further, as the image receiving sheet 2, a continuous sheet wound on a roll 7 as shown in the figure or a sheet-shaped sheet stacked in a stacker is used. In order to achieve high print quality without causing uneven transfer and misregistration of the thermal transfer sheet 1, the tension (back tension) between the supply side bobbin 5 and the thermal head 4 and the thermal head 4 and the winding head. It is important to properly control the tension (front tension) between the side bobbins 6. For this reason, the printer is provided with a tension adjusting means on one or both of the driving portions that engage with the supply side bobbin 5 and the winding side bobbin 6.

[0005]

However, if the printer is provided with the tension adjusting means for the thermal transfer sheet as described in the prior art, the mechanism of the printer body becomes complicated, resulting in an increase in cost and a failure. There is a problem.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a thermal transfer sheet cassette capable of simplifying the mechanism of the printer body.

[0007]

In order to achieve the above object, a cassette of the present invention comprises a cassette body and a lid body for covering the cassette body, and a supply side bobbin around which a thermal transfer sheet is wound and a winding side. In a cassette in which a bobbin is housed in the cassette body, at least one bobbin is provided with a tension adjusting portion, and the bobbin is configured to be attachable to and detachable from the cassette body without removing the tension adjusting portion from the cassette body. It is characterized in that the bobbin and the tension adjusting portion are engaged with each other when the bobbin is mounted on the cassette body.

Further, the supply side bobbin and / or the take-up side bobbin provided with the tension adjusting portion may be provided with a bearing portion of the cassette body at or near an engaging portion with the tension adjusting portion. It is preferable.

In the cassette of the present invention configured as described above, since the tension adjusting portion is provided on the bobbin, it is not necessary to provide the tension adjusting means for the thermal transfer sheet on the printer body, and the mechanism of the printer body is simplified. Close. In addition, the bobbin can be replaced while leaving the tension adjusting portion.

[0010]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 2 is a plan view showing an example of the cassette according to the present invention with the upper half lid thereof opened.

Reference numeral 10 in the drawing denotes a cassette body, which is a supply side bobbin 11 and a winding side bobbin 12 around which the thermal transfer sheet S is wound.
Is stored in it. The supply side bobbin 11 and the take-up side bobbin 12 are provided with flanges 11a and 12a at one end, respectively, and the outside of the flanges 11a and 12a serves as a rotation support portion, and the rotation support portion is the bearing portion 10a of the cassette body 10. It is inserted in 10b. On the other hand, tension adjusting portions 13 and 14 are provided on the other end sides of the supply side bobbin 11 and the winding side bobbin 12, and their mounting states are shown in an enlarged manner in FIGS. 3 and 4.

That is, the rotating shaft 15 of the tension adjusting portions 13 and 14 and the mounting shaft 1 of the bobbins 11 and 12 having the same diameter as the rotating shaft 15.
The end faces of 6 are located at the upward semicircular bearing portion 17 provided on the cassette body 10, the end face of the rotary shaft 15 is provided with a diametrical groove 15a, and the end face of the mounting shaft 16 is provided at the end face. A diametrical ridge 16a that fits in the groove 15a of the rotary shaft 15 is provided, and the ridge 16a is provided in the groove 15a.
The tension adjusting portions 13 and 14 and the bobbins 11 and 12 are engaged with each other by inserting. Therefore, the bobbins 11 and 12 can be attached to and detached from the cassette body 10 without removing the tension adjusting portions 13 and 14 from the cassette body 10. Since the bearing parts 17 of the cassette body 10 are provided at or near the engaging parts of the bobbins 11 and 12 and the tension adjusting parts 13 and 14, respectively.
The bobbins 11 and 12 and the tension adjusting portions 13 and 14 can rotate integrally in an engaged state.

In this embodiment, a slip actuating brake is used for the tension adjusting portion 13 of the supply side bobbin 11 and operates as follows. That is, when a rotational torque of a certain value or more is applied from the supply side bobbin 11 to the rotation shaft 15 of the operation brake engaged with the supply side bobbin 11, the rotation shaft 15 of the sliding operation brake rotates with the supply side bobbin 11. Therefore, the back tension can be controlled to be constant.

A slip actuating clutch is used in the tension controller 14 of the winding bobbin 12 and operates as follows. That is, if the rotational load acting between the rotary shaft 15 of the slip actuating clutch engaged with the take-up bobbin 12 and the rotary shaft on the drive unit side of the printer body is below a certain value, the drive in the slip actuated clutch The rotating shaft on the part side and the rotating shaft 16 of the winding bobbin 12 rotate without slipping.
When the rotational load acting between the rotary shaft 15 of the slip actuating clutch engaged with the take-up bobbin 12 and the rotary shaft on the drive unit side of the printer body becomes a certain value or more, the drive unit side of the slip actuating clutch is The rotary shaft and the rotary shaft 16 of the winding bobbin 12 rotate by sliding. Therefore, if the rotation speed of the rotation shaft on the drive unit side of the printer body is always set higher than the conveyance speed of the thermal transfer sheet, the rotation torque applied to the winding bobbin 12 can be kept constant.

The sliding actuating brake and the sliding actuating clutch can be of friction type, hysteresis type and powder type, but are not limited to these. Further, the slip actuating clutch can be used as a slip actuating brake by engaging one rotating shaft with the supply side bobbin and making the other rotating shaft a fixed shaft.

[0017]

As described above, in the cassette of the present invention, at least one bobbin is provided with the tension adjusting portion, and the bobbin can be attached to and detached from the cassette main body without removing the tension adjusting portion from the cassette main body. Due to the configuration, if this cassette is adopted, the mechanism of the printer main body can be simplified, and moreover, compared with the case where the tension adjusting means is provided in the printer main body, the cassette is used when the tension adjusting means needs to be replaced. Maintenance is easy because you only have to change. Also,
When the aptitude value of the back tension or the front tension differs depending on the thermal transfer sheet or the image receiving sheet to be used, it is possible to deal with it without changing the mechanism of the printer body.

Further, as compared with the construction in which the tension adjusting portion is removed from the cassette body together with the bobbin and then the tension adjusting portion is attached to and detached from the bobbin, the bobbin can be easily replaced and the tension adjusting portion may be lost. There is an advantage that there is no.

[Brief description of drawings]

FIG. 1 is a schematic diagram illustrating a printing mechanism unit in a printer.

FIG. 2 is a plan view showing an embodiment of a cassette according to the present invention with an upper half lid thereof opened.

FIG. 3 is an enlarged view of an engagement portion between a tension adjusting portion and a bobbin.

FIG. 4 is a sectional view taken along line XX of FIG.

[Explanation of symbols]

 10 cassette body 11 supply side bobbin 12 winding side bobbin 13,14 tension adjusting part 15 rotating shaft (tension adjusting part) 16 mounting shaft (bobbin) 17 bearing part (cassette main body) S thermal transfer sheet

Claims (2)

[Claims] 1. A cassette comprising a cassette body and a lid body for covering the cassette body, wherein a supply side bobbin around which a thermal transfer sheet is wound and a winding side bobbin are accommodated in the cassette body, and at least one bobbin is provided. The bobbin is configured to be attachable to and detachable from the cassette body without removing the tension adjusting portion from the cassette body. When the bobbin is mounted on the cassette body, the bobbin and the tension adjusting portion are attached. A cassette characterized by being engaged with. 2. The cassette according to claim 1, wherein the supply side bobbin and / or the take-up side bobbin provided with the tension adjusting portion has an engaging portion with the tension adjusting portion or a bearing portion of the cassette main body in the vicinity thereof. A cassette characterized by being provided with.