JPH0712245U - Thermal transfer recorder - Google Patents

Abstract

(57) [Abstract] [Purpose] To prevent blank printing and to prevent malfunctions due to ink on the thermal head when superimposing multiple colors. [Structure] 1 is a platen roller, 2 is a print head, 3 is recording paper, 42 is a photoelectric reflection sensor attached to the print head 2, and 45 is a peeling bar. The peeling bar 45 is attached to a support plate 43 that is swingably supported by the print head 2, and a partition plate 46 that operates the sensor 42 is mounted on the support plate 43.
Is provided.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a thermal transfer recording apparatus that superimposes a recording paper and an ink sheet, guides them between a platen roller and a printing head, and prints on the recording paper with a print head, and more particularly to a mechanism for detecting the presence or absence of an ink sheet. .

[0002]

[Prior art]

 As is well known, in this type of thermal transfer recording apparatus, thermal transfer recording papers or ink sheets respectively fed from a paper stock section or a sheet stock section are superposed on each other and guided onto a platen roller, and a print head sets a predetermined size on the recording paper. It is configured to print. The ink sheet is stored in the cartridge as a pair of the take-up roller and the supply roller. Among these, the take-up roller is received from the cartridge by the slider and moved to the take-up roller spreading position so that the ink sheet is placed on the platen. Be pulled. Then, the head descends onto the ink sheet, and the ink is transferred onto the recording paper by heating the thermal head. At this time, if there is no ink sheet on the platen, blank printing may occur or ink may adhere to the thermal head in the case of multicolor superposition, which may cause malfunction. Therefore, this type of thermal transfer recording apparatus is provided with a mechanism for detecting the presence or absence of an ink sheet.

As a thermal transfer recording apparatus provided with this kind of mechanism, there is Japanese Patent Application No. 4-24603 “thermal transfer recording apparatus” (hereinafter referred to as a prior application) filed by the present applicant. 3 and 4 are an overall external view and a side view of a main part of this prior application. The conventional technique will be described with reference to these drawings. 1 is a platen roller, 2 is a print head which is a thermal head vertically movable above the platen roller 1, 2a is a sheet peeling member, and 3 is a sheet peeling member. The recording paper is supplied from the recording paper supply roller 4 and is wound around the platen roller 1 by the guide rollers 5, 6 and 7.

The four ink sheets denoted by reference numerals 9a to 9d are stored and held in the cartridge 15 while being wound around the ink sheet supply rollers 10a to 10d (10d is not shown) which are paired with each other. Has been done. A sheet exchanging member 16 is arranged on the opposite side of the ink sheet stock portion A with the platen roller 1 interposed therebetween, and is movable in the direction of the sheet stock portion A, whereby the ink sheet take-up roller 11a, 11b, 11c or 11d is installed. The drawing roller is selectively pulled out to the stretching position B shown in the figure. In this case, the drawing shows a state in which the ink sheet take-up roller 11a forming a pair with the ink sheet supply roller 10a is pulled out.

The sheet exchange member 16 includes a sheet receiving block 12, a sheet take-up gear 13, a sheet take-up drive motor 14, etc., and a pair of left and right guide rails 17 arranged in parallel on both sides of the platen roller 1. Since the rotation of the motor 18 is movably held and the rotation of the motor 18 is transmitted through the belt 19 at the time of pulling out and returning the ink sheet take-up roller 11a, 11b, 11c or 11d, the take-up roller extending position B and the take-up roller extending position B are wound. It is configured to reciprocate between the pick-up roller transfer positions C (see FIG. 4). The take-up roller delivery position C is provided at the upper portion of the sheet stock portion A.

Each of the cartridges 15 disposed in the sheet stock portion A is commonly attached to a pair of left and right endless belts 20, and when the ink sheet take-up roller 11a, 11b, 11c or 11d is pulled out or returned. The rotation of the motor 21 is transmitted through the belt 20 so that the rotation of the motor 21 is selectively moved to the take-up roller transfer position C. Reference numeral 22 is a motor for moving the print head 2 up and down.

The cartridge 15 is formed in a horizontally long box shape with an open front surface, and thus has an upper plate 23a and a lower plate 23b facing each other vertically, a pair of side plates facing each other (not shown), and a back plate. The face plates 23c are integrally provided, and the shaft ends of the roller shafts 26 and 27 of the pair of the ink sheet supply roller 10a and the ink sheet take-up roller 11a are rotatably supported on the front end faces of the left and right side plates. . A rotation detection plate 24 formed of a regular square is attached to one end of the roller shaft 26 of the ink sheet supply roller 10a. The length of the diagonal line of the rotation detection plate 24 is larger than the diameter of the ink sheet supply roller 10a. It is set. Therefore, each corner of the rotation detection plate 24 appropriately protrudes outward from the outer circumference of the ink sheet supply roller 10a. A longitudinally elongated notch 23d that allows the rotation detecting plate 24 to rotate is formed in a portion of the back plate 23c of the cartridge 15 corresponding to the rotation detecting plate 24.

A stopper 28 and a seat end detection device 30 that forms a seat end detection mechanism 29 together with the rotation detection plate 24 are disposed near the cutout 23d. The stopper 28 is disposed above a sheet end detection device 30 which will be described later and normally does not contact the rotation detection plate 24, and is used when the ink sheet take-up roller 11a is pulled out or when the ink sheet is taken up. When the roller 11a is returned from the take-up roller mounting position B to the cartridge 15 and moved to the take-up roller transfer position C by moving the cartridge 15 upward from the sheet stock portion A by a predetermined distance, as shown in FIG. As shown in the figure, the rotation detection plate 24 is brought into contact with the rotation detection plate 24, thereby preventing the ink sheet supply roller 10a from rotating.

The seat end detection device 30 is a rotation plate that is rotatably arranged in the vertical direction via a bracket member 32 on a fixed plate 31 that is arranged in parallel in the rear of the cartridge 15 with an appropriate interval. A sensor S including a lever 33, a shutter plate 34 provided integrally with the rotating lever 33, a light emitting diode 35 and a phototransistor 36 that face each other across the shutter plate 34, and a rotating lever 33. 4 is provided with a spring 37 that urges the rotation detecting plate 24 counterclockwise in FIG. 4, and when the rotation detecting plate 24 rotates together with the ink sheet supply roller 10a during printing, the rotation lever 33 is kicked by a corner portion of the rotation detecting plate 24. Each time, the shutter plate 34 is rotated against the spring 37, and the shutter plate 34 blocks light emitted from the light emitting diode 35 and received by the phototransistor 36. Therefore, the sensor S delivers a pulsed output signal. On the other hand, when the ink sheet 9a is used up and the ink sheet supply roller 10a stops, the rotation detection plate 24 also stops, so that the output signal from the sensor S is not sent. In the control circuit, if a signal is not sent from the sensor S even if a predetermined amount of paper is sent (even if printing is performed), it is determined that the ink c and 9a are gone, and the ink sheet take-up roller 11a is returned to the cartridge 15. The cartridge is replaced with a new cartridge.

[0010]

[Problems to be solved by the device]

 By the way, as shown in FIG. 5, when the ink sheet 9a disappears with the completion of printing, the detection operation by the sheet end mechanism 29 also stops with the completion of printing, so that the ink sheet 9a is wound around the ink sheet supply roller 10a. The seat end mechanism 29 does not detect the end even though the seat end is lost. Therefore, even if the take-up roll 11a on which the ink sheet 9a is completely wound up is returned to the cartridge 15 when printing is completed, without noticing that the ink sheet 9a is no longer wound around the ink sheet supply roller 10a, Since the ink sheet take-up roller 11a is used again, when the ink sheet take-up roller 11a is pulled out to the take-up roller spreading position B, the ink sheet is stretched between the ink sheet supply roller 10a and the ink sheet take-up roller 11a. Absent. If the print head 2 is lowered in this state, there is a problem that blank printing is performed without an ink sheet until the sheet end is detected. In addition, there is a problem that ink is attached to the thermal head when superimposing multiple colors, which causes the thermal head to malfunction.

Therefore, the present invention has been made in view of the above-mentioned conventional inconveniences or problems, and an object of the present invention is to reliably detect the absence of an ink sheet before the start of printing, thereby preventing the blank printing. It is an object of the present invention to provide a thermal transfer recording apparatus which prevents a failure caused by ink adhering to a thermal head when superimposing multiple colors.

[0012]

[Means for Solving the Problems]

 In order to achieve this object, a thermal transfer recording apparatus according to the present invention has a print head in which an ink sheet fed from an ink sheet supply roller and wound on an ink sheet take-up roller and a recording paper are superposed on a platen roller. A thermal transfer recording device for printing on recording paper by means of a support plate swingably supported by the print head, and an ink sheet arranged at an end of the support plate to press the ink sheet against the platen roller during printing. A sheet peeling member that attaches and rotates the support plate, an operating member that is provided on the support plate and rotates integrally with the supporting plate, and a detection operation based on the rotation of the operating member to detect the presence or absence of an ink sheet. And a detection switch for performing the operation.

[0013]

[Action]

 According to the present invention, when the print head is lowered to be positioned on the platen roller to perform the printing operation, the sheet peeling member engages with the ink sheet, whereby the support plate rotates and is detected by the operating member. Operate the switch. When there is no ink sheet, the sheet peeling member does not engage, the support plate does not rotate, and the detection switch does not operate by the operating member.

[0014]

【Example】

 An embodiment of the present invention will be described below with reference to the drawings. 1 and 2 are side views of a main part of a thermal transfer device according to the present invention, showing a state with an ink sheet and a state without an ink sheet, respectively. In these figures, the same components as those of the conventional technique are designated by the same reference numerals and detailed description thereof will be omitted. Further, the overall configuration is the same as that of the above-mentioned prior art, so that the illustration is omitted.

In these figures, 41 is an arm whose one end is attached to the print head 2 and whose other end is fixed to a shaft 40 which is coaxially integrated with the rotation shaft of the motor (not shown). The arm 41 swings clockwise and counterclockwise around the shaft 40 by the forward and reverse rotations, whereby the print head 2 moves up and down to come into contact with and separate from the platen roller 1. A photoelectric reflection sensor 42 is attached to the upper surface of the print head 2.

Reference numeral 43 denotes a support plate swingably supported by pins 44 implanted in the print head 2, and a peeling bar 45, which is a sheet peeling member, is attached to the tip of the plate. The support plate 43 is normally hung vertically downward due to the weight of the peeling bar 45. When the peeling bar 45 engages with the ink sheet 9a, the support plate 43 is rotated counterclockwise around the pin 44 in the figure. After being rotated by a predetermined angle by the peeling bar 45, the rotation is regulated by a stopper (not shown), and the ink sheet 9a is pressed against the platen roller 1 to peel the ink sheet 9a from the recording paper 3.

Reference numeral 46 denotes a partition plate which is an operating member, and is attached so as to be orthogonal to the substantially central portion of the support plate 43 and swings integrally with the support plate 43 so that the front end faces the photoelectric reflection sensor 42. Is formed in. Reference numeral 47 is a slider for moving the ink sheet take-up roller 11a between a roller extending position B and a roller transfer position (C in FIG. 4).

Next, the operation of the thermal transfer recording apparatus thus configured will be described. First, the ink sheet 9a is pulled from an ink sheet supply roller (not shown) by the ink sheet take-up roller 11a which is moved in the normal operation, that is, from the roller transfer position to the roller extension position B, and the ink is applied onto the platen roller 1. When the sheet 9a is present, the peeling bar 45 engages the ink sheet 9a before the print head 2 lowered for the printing operation contacts the platen roller 1, and the support plate 43 is fixed by the pin 44. Rotate counterclockwise as the center. By this rotation, the partition plate 46 whose tip is located on the photoelectric reflection sensor 42 is rotated, and the tip is disengaged from the photoelectric reflection sensor 42, and it is determined that there is an ink sheet, and printing is possible. Printing is started when the head 2 descends and comes into contact with the platen roller 1.

On the other hand, when the take-up roll 11a in which all the ink sheets are mistakenly taken up is positioned at the roller stretching position B, the ink sheet is not pulled between the ink sheet supply roller and As shown in FIG. 2, there is no ink sheet on the platen roller 1. In this state, even if the print head 2 descends, nothing comes into contact with the peeling bar 45, so that the support plate 43 keeps hanging down due to the weight of the peeling bar 45, and the partition plate 46 makes the photoelectric reflection sensor 42. The printer keeps the ink sheet out state and keeps the ink sheet out state. If this state continues, the motor is stopped when the print head 2 is positioned before the platen roller 1, the descent of the print head 2 is stopped, and the printing operation is also stopped.

[0020]

[Effect of device]

 As described above, according to the present invention, in a thermal transfer recording apparatus that prints on a recording sheet with a print head, a support plate swingably disposed on the print head and an end portion of the support plate are disposed. The sheet peeling member that presses the ink sheet against the platen roller at the time of printing to rotate the support plate, the operating member that is provided on the support plate and that rotates integrally with the support plate, and the detection by the rotation of the operating member A detection switch that operates to detect the presence or absence of the ink sheet is provided.Before the print head descends and contacts the platen roller, the sheet peeling member engages the ink sheet and rotates the support plate to detect the detection sheet. Since the presence / absence of the ink sheet is detected by the check, when there is no ink sheet, the absence of the ink sheet is detected before the print head contacts the platen roller, and the print head is detected. The without causing contact with the platen roller, you can stop the printing operation, and therefore, it is possible to prevent air printing, a failure due to the ink stick to the thermal head in the case of multi-color superposition can be prevented.

[Brief description of drawings]

FIG. 1 is a side view of a main part of a thermal transfer recording apparatus according to the present invention.
The case where there is an ink sheet is shown.

FIG. 2 is a side view of a main part of the thermal transfer recording apparatus according to the present invention.
The case where there is no ink sheet is shown.

FIG. 3 is an overall external perspective view of a general thermal transfer recording apparatus.

FIG. 4 is a side view of a main part of a conventional thermal transfer recording device.

FIG. 5 is a side view of a main part of a conventional thermal transfer recording apparatus, showing a state where an ink sheet is out.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Platen roller 2 Print head 3 Recording paper 9a-9d Ink sheet 10a-10d Ink sheet supply roller 11a-11d Ink sheet take-up roller 15 Cartridge 42 Photoelectric reflection sensor 43 Support plate 45 Peeling bar 46 Partition plate

Claims (1)

[Scope of utility model registration request] 1. A thermal transfer recording apparatus for superposing an ink sheet fed from an ink sheet supply roller and taken up by an ink sheet take-up roller and a recording sheet on a platen roller and printing on the recording sheet by a print head, Provided on the support plate, a support plate swingably supported by the print head, a sheet peeling member arranged at an end portion of the support plate for pressing the ink sheet against the platen roller during printing and rotating the support plate. A thermal transfer recording apparatus provided with an operating member that rotates integrally with the support plate and a detection switch that operates by the rotation of the operating member to detect the presence or absence of an ink sheet.