JP3849796B2 - Thermal transfer printer - Google Patents

Description

  The present invention relates to a thermal transfer printer for printing an image based on information input from an image forming apparatus, for example.

  Conventionally, as a technology of a thermal transfer printer, there is one described in Patent Document 1 and the like, and an example thereof will be described based on FIGS. 6 to 9. This is because the inside of the iron plate base frame 1 bent into a substantially U shape. A paper feed roller 2, a feed roller 3, and a platen roller 4 are arranged at predetermined intervals along a paper feed path formed from the front end portion toward the rear end portion, and are disposed above the paper feed roller 2. By disposing an elastically deformable separating plate 6 from the paper roller 5 to the upstream side of the feed roller 3 in the paper feed path A, a paper discharge path B is formed, and a pressing roller 7 that is elastically pressed against the feed roller 3 is provided. A thermal head 9 that can be pressed and separated from the platen roller 4 by a rotation mechanism 8, a pressing mechanism 10 for pressing down the thermal head 9, and a paper cassette for storing paper P is provided. An ink sheet cassette 13 that accommodates an ink sheet S in which yellow, magenta, and cyan colored bands are formed in a repeating order is removably connected to a sheet feeding port 12 formed at the front end of the base frame 1. It is detachably disposed in the base frame 1 through an insertion hole 14 formed in one side plate portion 1 a of the frame 1.

  The rotating mechanism 8 includes a cross beam portion 16a to which the thermal head 9 is fixed, a substantially L-shaped heat radiation plate portion 16b bent from the rear side edge of the cross beam portion 16a and extending backward, and a cross beam portion 16a. A pair of left and right arc-shaped arm portions 16c and 16d that are bent at right angles from both ends of the arm portion and extend rearward, and a pair of left and right arms that are bent at right angles from the front ends of the arm portions 16c and 16d and extend sideways. It has an aluminum plate frame 16 composed of joint pieces 16e and 16f, and the base end portions of the arm portions 16c and 16d are raised and lowered to a pair of left and right bearing plates 17 cut and raised from the bottom plate portion 1b of the base frame 1 The frame body 16 is urged in the standing direction a by a coil spring 19 that is pivotally supported so that both ends are engaged with the arm portion 16d and the hook portion 18 of the base frame 1.

  The push-down mechanism 10 includes a support shaft 21 that is constructed to be capable of forward and reverse rotation c and d on an upper portion between both side plates 1a and 1c of the base frame 1, and a pair of left and right fan plates that are fitted to both ends of the support shaft 21. 22, a circular arc plate 23 integrally formed on the inner surface of each fan plate 22, and a linear spring 24 disposed in each circular arc plate 23 with the tip protruding outward. A tooth portion 25 formed on the fan plate 22 is linked to a printing motor 28 fixed to the bracket 26 via a gear mechanism 27 (not shown) provided between the other side plate 1c and the bracket 26. As shown in FIGS. 7 and 8, by driving the printing motor 28 from the state in which each arc plate 23 is brought into contact with each engagement piece 16e, 16f, both fan plates 22 are rotated forward c. The distal end portion of each spring 24 is pressed against each engaging piece 16e, 16f, and both arm portions 16c, 6d was rotated in laid down direction b, it is pressed against the thermal head 9 with the platen roller 4 [FIG. 10 (b) refer to Fig.

  The ink sheet cassette 13 has a pair of front and rear cylindrical portions 13a and 13b, and two connecting rods 13c that integrally connect both ends of the cylindrical portions 13a and 13b, and is supplied in the rear cylindrical portion 13a. The ink sheet S is passed between the reel 30 and the take-up reel 31 in the front cylindrical portion 13b. By inserting the ink sheet cassette 13 into the base frame 1 from the insertion hole 14, the ink sheet S is formed. Inserted between the thermal head 9 and the platen roller 4, and as shown in FIG. 9, the end of the supply reel 30 is fitted to a supply shaft 32 protruding from the other side plate 1c, and the take-up reel 31 is inserted. Is fitted to a take-up shaft 33 pivotally supported on the other side plate 1c, and the take-up shaft 33 is linked to a feed motor 34 via a gear mechanism 27. Drive By rotating the winding reel 31 in the winding direction e, taking up the ink sheet S a predetermined length on the reel 31 preparative the winding.

  The feed motor 34 is selectively connected not only to the take-up reel 31 but also to the paper feed roller 2, the feed roller 3 and the paper discharge roller 5 through a clutch mechanism incorporated in the gear mechanism 27. In FIG. 7, reference numeral 35 denotes a push-up plate for pushing up the paper P in the paper cassette 11, and is urged upward by a spring 35a.

  As shown in FIGS. 8 and 9, both ends of the iron plate top plate 36 are placed on a pair of left and right receiving plates 1 d and 1 e that are bent at right angles outward from the upper end edges of the side plates 1 a and 1 c of the base frame 1. Each receiving plate is inserted by inserting a substantially L-shaped positioning piece 37 extending rearward from the rear edges of both ends of the top plate 36 into positioning holes 38 penetrating the receiving plate portions 1d and 1e. Screw insertion holes 36a penetrating both ends of the top plate 36 are concentrically positioned in the screw holes 39 penetrating the portions 1d and 1e, and two screws are inserted into the screw holes 39 through the screw insertion holes 36a. By screwing 40, both ends of the top plate 36 are fastened to the receiving plate portions 1d and 1e.

  Explaining the printing procedure, as shown in FIG. 10A, the paper P is fed from the paper cassette 11 between the thermal head 9 and the platen roller 4 by the paper feed roller 2 and the feed roller 3 in the paper feed direction f. When the trailing edge of the paper P reaches between the feed roller 3 and the pressing roller 7, as shown in FIG. 10B, the paper feeding is stopped, and then the feed roller 3 is rotated forward and backward. As a result, the paper P is reciprocated three times f and g along the paper feed path A, and the thermal head 9 is pushed down by the spring 24 of the push-down mechanism 10 in the three return paths g. By pressing against the platen roller 4 through the sheet S and paper P, yellow, magenta and cyan are printed on the paper P, and as shown in FIG. The paper sheet P is discharged to the sheet discharge direction h by the discharge roller 5 through the upper separator plate 6.

  As shown in FIGS. 11 and 12, a shaft hole 46 is formed through the base end portion of each arm portion 16c, 16d, and the cylindrical support shaft 17a is integrally projected concentrically by drawing each bearing plate 17. A cylindrical extension shaft 47 is concentrically connected to one support shaft 17 a by a connection screw 48.

The attachment procedure of the arm portions 16c and 16d will be described. As shown by the phantom line in FIG. 11, the shaft hole 46 of one arm portion 16d is fitted to the extension shaft 47, whereby the shafts of both the arm portions 16c and 16d are fitted. The holes 46 are respectively positioned concentrically with the respective support shafts 17a, and then both the arm portions 16c and 16d are slid along the extension shaft 47, whereby the shaft holes 46 of the both arm portions 16c and 16d are respectively supported. The shaft 17a is fitted.
JP-A-11-254715

  In the above conventional configuration, the extension shaft 47 is used to fit the shaft holes 46 of the both arm portions 16c, 16d to the respective support shafts 17a. In this case, the extension shaft 47 and the extension shaft 47 are connected to each other. A connecting screw 48 for connecting to the support shaft 17a is necessary, and the number of parts increases, and it takes time and effort to connect the extension shaft 47 to the support shaft 17a with the connecting screw 48, which is troublesome. Production costs are high.

  Further, since each support shaft 17a is short and is only pressed by the coil spring 19 so that the shaft hole 46 is not detached from each support shaft 17a, an excessive impact is applied, for example, by dropping the base frame 1 or the like. When this occurs, the coil spring 19 may be compressed by the impact force, and the shaft hole 46 of the other arm portion 16c may be disengaged from the support shaft 17a. In this case, the turning operation of both arm portions 16c and 16d is smooth. Can not be done.

  SUMMARY OF THE INVENTION In view of the above-mentioned conventional drawbacks, the present invention provides a thermal transfer printer in which the arm portion is attached with an inexpensive and simple structure, and the shaft hole of the arm portion is not accidentally detached from the support shaft. It is aimed.

In order to achieve the above object, according to the first aspect of the present invention, the feed roller, the feed roller, and the platen roller are respectively spaced at predetermined intervals along the feed path formed from the front end portion to the rear end portion in the base frame. The paper discharge path is connected to the upstream side of the feed roller of the paper supply path, and a thermal head that can be pressed and separated from the platen roller by a rotation mechanism is provided. A pair of left and right arms each having a pair of left and right arms extending rearward from both ends of the cross beam portion to which the head is fixed, and having a shaft hole penetrating from the base end of each arm, and being cut and raised from the bottom plate of the base frame A cylindrical support shaft is concentrically and integrally provided on the bearing plate, and a shaft hole of each arm portion is fitted to each support shaft to bias the thermal head toward the platen roller. The coil spring is Between the thermal head and the platen roller, and an ink sheet is inserted between the thermal head and the platen roller. The paper is reciprocated along the supply path, and both arms are rotated in the return path. subjected to printing on the paper by pressing the platen roller through the ink sheet and the paper to the thermal head Te, the printing completed paper Te thermal transfer printer odor which is adapted to discharge along the discharge path, before Symbol one bearing the bottom plate of the base frame close to the plate, T-shaped consisting of a guide hole parallel to the axis of the supporting shafts, a free hole extending along the lower edge of one of the bearing plates communicates with the guide hole A hole is formed, and a guide piece that is detachably engaged with the guide hole is integrally provided on one arm portion, and is close to the shaft hole between the shaft hole and the cross beam portion of the one arm portion. in position, projects toward the bearing plate L Piece is integrally projected a gap loosely entrant stopper piece between the L-shaped piece and one arm portion is integrally projected from the upper end of one of the bearing plate, the guide piece in the guide hole After the shaft holes of both arm portions are positioned concentrically with the respective support shafts by engaging, the guide pieces are slid along the guide holes to fit the shaft holes of both arm portions to the respective support shafts. The two arm portions are rotated to the platen roller side, and a stopper piece is loosely inserted between the L-shaped piece and one arm portion .

According to a second aspect of the present invention, a paper feed roller, a feed roller, and a platen roller are arranged at predetermined intervals along a paper feed path formed from the front end portion toward the rear end portion in the base frame. A paper discharge path is connected upstream of the feed roller of the paper supply path, a thermal head that can be pressed and separated from the platen roller by a rotating mechanism is provided, and a transverse beam portion to which the rotating mechanism fixes the thermal head A pair of left and right arm portions extending rearward from both ends of each of the shafts, shaft holes extending through the base end portions of the respective arm portions, and a cylindrical support for the pair of left and right bearing plates cut and raised from the bottom plate portion of the base frame. The shaft is concentrically and integrally protruded, and a shaft spring of each arm portion is fitted to each support shaft, and a coil spring that biases the thermal head toward the platen roller in the direction of approaching the one of the one. It is interposed between the arm part and the base frame. An ink sheet is inserted between the thermal head and the platen roller, the paper is reciprocated along the supply path, and both arms are rotated along the return path so that the thermal head passes through the ink sheet and the paper. In the thermal transfer printer in which the sheet is printed by pressing it against the platen roller and the printed sheet is discharged along the sheet discharge path, the bottom plate portion of the base frame approaches the one bearing plate, and the guide hole parallel to the axis of the supporting shafts, T-shaped hole made of a free hole extending along the lower edge of one of the bearing plates communicates with the guide hole is formed, disengageably to said guide hole A guide piece that engages with each other is integrally projected on one arm part, and the shaft holes of both arm parts are positioned concentrically with the respective support shafts by engaging the guide pieces with the guide holes , The By sliding along the Id piece in the guide hole, it is characterized in that the axial hole of the arms and so fitted to the axles.

According to a third aspect of the present invention, in the invention of the second aspect, the L projecting toward the bearing plate at a position close to the shaft hole between the shaft hole and the cross beam portion of the one arm portion. A character piece is integrally protruded, and a stopper piece that can be loosely inserted into a gap between the L shape piece and one arm portion is integrally protruded on the upper end of one bearing plate, and a shaft hole of both arm portions. Is fitted to each support shaft, and then both arm portions thereof are rotated to the platen roller side so that a stopper piece is loosely inserted between the L-shaped piece and one arm portion . .

The invention according to claim 1 corresponds to one embodiment (see FIGS. 1 to 5), and according to this, a guide piece integrally provided on one arm portion is used as a bottom plate of a base frame. By engaging the guide holes formed in the portions, the shaft holes of both arm portions are positioned concentrically with the respective support shafts, and then the guide pieces are simply slid along the guide holes . The shaft hole can be easily fitted to each support shaft. In this case, the conventional extension shaft and the connection screw for connecting the extension shaft are not necessary. Only production costs can be reduced.

Further, after the shaft holes of both arm portions are fitted to the respective support shafts, the both arm portions are rotated to the platen roller side, so that the stopper piece is allowed to play between the L-shaped piece and one arm portion. Even if an excessive impact is applied by, for example, dropping the base frame, the L-shaped piece is caught by the stopper piece by the impact force, so that the shaft hole of the other arm part is a support shaft as in the conventional case. There is no risk of disengagement from both, and the pivoting operation of both arm portions can be performed smoothly.

The invention according to claim 2 corresponds to the basic form, and according to this, the guide piece integrally protruding on one arm portion is engaged with the guide hole formed in the bottom plate portion of the base frame. Thus, after the shaft holes of both arm portions are positioned concentrically with the respective support shafts, the guide holes can be easily fitted to the respective support shafts by simply sliding the guide pieces along the guide holes. In this case, since there is no need for a conventional extension shaft and a connecting screw for connecting the extension shaft, the manufacturing cost can be reduced by the amount that is no longer necessary.

According to the invention described in claim 3, after the shaft holes of both arm portions are fitted to the respective support shafts, the both arm portions are rotated to the platen roller side, whereby the L-shaped piece and one arm The stopper piece is loosely inserted between the two parts, and even if an excessive impact is applied, for example, by dropping the base frame, the L-shaped piece is caught by the stopper piece by the impact force. There is no fear that the shaft hole of the arm portion will be detached from the support shaft, and the rotating operation of both arm portions can be performed smoothly.

1 to 4 show a thermal transfer printer according to an embodiment of the present invention. The thermal transfer printer is close to one bearing plate 17 and is attached to the bottom plate portion 1b of the base frame 1 at the axis O of both support shafts 17a. and the guide hole 50a in parallel, T-shaped hole 50 consisting of a free hole 50b extending along the lower edge of the guide hole 50a communicating with the one bearing plate 17 is formed which is opposite to the T-shaped hole 50 and A semicircular guide piece 51a is integrally provided on the arm portion 16d via a protrusion 51 wider than the guide hole 50a, and the outer diameter r of the guide piece 51a is set to be substantially the same as the width h of the guide hole 50a. The width i of the free hole 50b is set larger than the thickness t of the guide piece 51a.

  An L-shaped piece 52 is integrally projected from the base end portion of the arm portion 16d toward the bearing plate 17, and a stopper piece 53 that can be loosely inserted into a gap β between the L-shaped piece 52 and the arm portion 16d is provided on the bearing plate 17. Is integrally projected at the upper end of the.

The procedure for attaching the arm portions 16c and 16d will be described. As shown in FIGS. 5A to 5C, the guide pieces 51a are engaged with the guide holes 50a so that the shaft holes 46 of the both arm portions 16c and 16d are engaged. Are respectively concentrically positioned on the respective support shafts 17a (see phantom lines in FIG. 1), and the guide pieces 51a are slid along the guide holes 50a, whereby the shaft holes 46 of the both arm portions 16c and 16d are respectively supported. The shaft 17a is fitted (see the solid line in FIG. 1). As a result, the guide piece 51a is fitted into the free hole 50b (see phantom line in FIG. 5C), and the arm portions 16c and 16d are allowed to freely rotate about the support shaft 17a. Next, both arm parts 16c and 16d are rotated in the lying direction b on the platen roller 4 side, and the stopper piece 53 is loosely inserted between the L-shaped piece 52 and one arm part 16d [FIG. 4 (a). To (c)].

According to the above configuration, by engaging the guide piece 51a integrally projecting on the arm portion 16d with the guide hole 50a formed in the bottom plate portion 1b of the base frame 1, the shaft holes 46 of both the arm portions 16c and 16d are respectively formed. After positioning concentrically with each supporting shaft 17a, the shaft holes 46 of both arm portions 16c and 16d can be easily fitted to each supporting shaft 17a simply by sliding the guide piece 51a along the guide hole 50a. In this case, since there is no need for the conventional extension shaft 47 and a connection screw 48 (see FIG. 11) for connecting the extension shaft 47, the manufacturing cost can be reduced by the amount that is unnecessary. Can do.

Further, after fitting the shaft holes 46 of the both arm portions 16c and 16d to the respective support shafts 17a, the both arm portions 16c and 16d are rotated to the platen roller 4 side, whereby the L-shaped piece 52 and one of the arm portions 16c and 16d are rotated . The stopper piece 53 is loosely inserted between the arm portion 16d and the L-shaped piece 52 is caught on the stopper piece 53 by the impact force even if an excessive impact is applied, for example, by dropping the base frame 1 or the like. Thus, there is no possibility that the shaft hole 46 of the arm portions 16c, 16d is detached from the support shaft 17a as in the prior art, and the turning operation of both the arm portions 16c, 16d can be performed smoothly.

1 is a cross-sectional view of a thermal transfer printer according to an embodiment of the present invention. It is a disassembled perspective view of the rotation mechanism. It is a disassembled perspective view of the principal part. (A) is the side view of the principal part which shows the attachment state of an arm part, (b) is an AA arrow directional view, (c) is a BB arrow directional view. (A) is a side view of the principal part which shows the attachment procedure of an arm part, (b) is CC arrow directional view, (c) is DD arrow directional view. It is a perspective view of a thermal transfer printer. It is the longitudinal cross-sectional view. FIG. It is the same top view. (A)-(c) is a schematic longitudinal cross-sectional view which shows the same printing procedure. It is a cross-sectional view showing a conventional example. It is a disassembled perspective view of the rotation mechanism.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Base frame 1b Bottom plate part of base frame 2 Paper feed roller 3 Feed roller 4 Platen roller 8 Rotating mechanism 9 Thermal head 16 Frame body 16a Frame cross beam part 16c, 16d Frame body arm part 17 Bearing plate 17a Bearing plate 19 Coil spring 46 Arm shaft hole 47 Extension shaft 48 Connection screw 50 T-shaped hole 50a T-shaped hole guide hole 50b T-shaped free hole 51a Guide piece 52 L-shaped piece 53 Stopper piece β Clearance O Support Axis of shaft A Feeding path B Discharging path P Paper S Ink sheet

Claims (3)

A paper feed roller, a feed roller, and a platen roller are arranged at predetermined intervals along a paper feed path formed from the front end to the rear end in the base frame, and upstream of the feed roller in the paper feed path. And a pair of left and right thermal heads extending rearward from both ends of the cross beam portion to which the thermal head is fixed. A shaft hole is provided in the base end portion of each arm portion, and a cylindrical support shaft is concentrically provided integrally with a pair of left and right bearing plates cut and raised from the bottom plate portion of the base frame. A coil spring is provided between the one arm portion and the base frame to fit the shaft hole of each arm portion to each support shaft and urge the thermal head toward the platen roller in the direction of approaching the thermal head. Intervening with the thermal head An ink sheet is inserted between the latin rollers, and the paper is reciprocated along the supply path, and both arms are rotated on the return path to press the thermal head against the platen roller via the ink sheet and the paper. subjected to printing on the paper by, the printing completed paper Te thermal transfer printer odor which is adapted to discharge along the discharge path, the bottom plate portion of the base frame close before SL one of the bearing plate, supporting shafts and the guide hole parallel to the axis of, T-shaped hole made of a free hole extending along the lower edge of one of the bearing plates communicates with the guide hole is formed, detachably engaged with the guide hole The guide piece is integrally projected on one arm portion, and an L-shaped piece projecting toward the bearing plate is integrally formed between the shaft hole and the cross beam portion of the one arm portion at a position close to the shaft hole. Projecting from the L-shaped piece and one arm Clearance loosely entrant stopper piece is integrally projected from the upper end of one of the bearing plate, concentrically each of support shafts the shaft hole of the arms by engaging the guide piece in the guide hole After the positioning, the guide pieces are slid along the guide holes so that the shaft holes of both arm portions are fitted to the respective support shafts, and both arm portions are rotated to the platen roller side to form L-shaped pieces. A thermal transfer printer characterized in that a stopper piece is loosely inserted between the arm and one arm portion . A paper feed roller, a feed roller, and a platen roller are arranged at predetermined intervals along a paper feed path formed from the front end to the rear end in the base frame, and upstream of the feed roller in the paper feed path. And a pair of left and right thermal heads extending rearward from both ends of the cross beam portion to which the thermal head is fixed. A shaft hole is provided in the base end portion of each arm portion, and a cylindrical support shaft is concentrically provided integrally with a pair of left and right bearing plates cut and raised from the bottom plate portion of the base frame. A coil spring is provided between the one arm portion and the base frame to fit the shaft hole of each arm portion to each support shaft and urge the thermal head toward the platen roller in the direction of approaching the thermal head. Intervening with the thermal head An ink sheet is inserted between the latin rollers, and the paper is reciprocated along the supply path, and both arms are rotated on the return path to press the thermal head against the platen roller via the ink sheet and the paper. In the thermal transfer printer in which printing is performed on the paper and the printed paper is discharged along the paper discharge path, the shafts of both support shafts are placed on the bottom plate portion of the base frame close to the one bearing plate. and the guide hole parallel to the heart, T-shaped hole made of a free hole extending along the lower edge of one of the bearing plates communicates with the guide hole is formed which is detachably engaged with the guide hole guides A piece is integrally projected on one arm portion, and the guide pieces are engaged with the guide holes to position the shaft holes of both arm portions concentrically with the respective support shafts, and then the guide pieces are guided. along the hole By sliding, thermal transfer printers, characterized in that the axial hole of the arms and so fitted to the axles. An L-shaped piece projecting toward the bearing plate is integrally projected between the shaft hole of the one arm portion and the cross beam portion at a position close to the shaft hole , and the L-shaped piece and one arm portion are A stopper piece that can be loosely inserted into the gap between the two bearing plates is integrally projected at the upper end of one bearing plate. After the shaft holes of both arm portions are fitted to the respective support shafts, the both arm portions are connected to the platen roller. 3. The thermal transfer printer according to claim 2, wherein the stopper piece is loosely fitted between the L-shaped piece and one of the arm portions .

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