JP2008030356A - Image forming apparatus of thermal head type, manufacturing method for frame, and blank used in frame which support thermal head - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce manufacturing costs of a frame which supports a thermal head. <P>SOLUTION: The frame 7 consists of one sheet of an aluminum plate A1 and is equipped with a lateral girder part 71, a radiation part 72, and arms 73 articulated with both side ends of the lateral girder part 71. The arms 73 are comprised of standing end parts 73a articulated via bending parts w1 with both the side ends of the lateral girder part 71, arm parts 73b of a curved shape articulated with the standing end parts 73a, and pivot parts 73c articulated with front ends of the arm parts 73b. The radiation part 72 is articulated from the lateral girder part 71 located at one side x1 of the aluminum plate A1 towards the other side x2 via a bending part w2. The arms 73 form a blank 70 along the shape of the frame 7 from the aluminum plate A1 so that top parts T of curved curves of the arm parts 73b are directed towards the radiation part 72 side via a notch, and also so that the arm parts 73b are located adjacent to the radiation part 72. The frame 7 is shaped by bending the blank 70. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a thermal head type image forming apparatus, and more particularly, to reduce the manufacturing cost of a frame that supports a thermal head.

  For example, in a thermal head type image forming apparatus, an ink ribbon coated with a sublimation dye is superimposed on a recording paper made of photographic paper, and electric energy corresponding to image information is applied to a thermal head (thermal head). The sublimation dye applied to the ink ribbon by the thermal energy generated from the thermal head is sublimated and transferred onto a recording paper made of a dedicated printing paper, for example, predetermined printing (printing), For example, color printing is performed. For this reason, in the sublimation type image forming apparatus, for example, by controlling the energization amount to the thermal head, that is, the heat generation amount of the head printing unit, the image having the floor adjustment is reproduced, so that it is small and simple. It has attracted widespread attention as being capable of reproducing high-quality color images despite its simple structure.

  In general, in a thermal head type image forming apparatus, when color printing is performed, for example, recording sheets stacked in a paper feeding cassette are once transported to the downstream side of the image forming unit, and then fed. For example, yellow (Y) ink on the ink ribbon is transferred to the recording paper while being conveyed in the direction of the paper discharge unit provided at the top of the paper cassette. Thereafter, the recording paper is conveyed to the downstream side of the image forming unit, and, for example, magenta (M) ink is transferred onto the recording paper in an overlapping manner, as in the above-described yellow. Thereafter, cyan (C) is transferred in the same manner, and then an overcoat is applied as necessary.

  As described above, since the recording paper reciprocates in the image forming unit, conventionally, as shown in FIG. 8, the thermal head 41 can be rotated so as to be pressed against and separated from a platen roller (not shown). It is attached to the frame body 7. Further, since the thermal head 41 generates heat during printing and needs to effectively dissipate heat, the frame body 7 is made of an expensive aluminum plate as compared with an iron plate or a steel plate. In the figure, reference numeral 72 denotes a heat radiating portion.

  For example, as shown in FIG. 9, the above-described frame body 7, after cutting out one aluminum plate A1 along the shape of the frame body 7, a blank 70 which is a planar frame body material, It was bent along the imaginary line W (for example, see Patent Document 1: FIGS. 9 and 10).

  However, in the manufacturing method described above, as shown in FIG. 9, the apex portion T of the curve of the curved arm 73 formed on the frame body 7 is located on the outermost peripheral portion a1 on both sides of the aluminum plate A1. Therefore, the material of the blank 70 for manufacturing the frame body 7, that is, the width H1 of the aluminum plate A1 is increased. As a result, there is a problem that the aluminum plate A1 having a large area is necessary, and there are many parts that become chips, and the manufacturing cost of the frame body 7 is naturally increased.

As a countermeasure, for example, an arm part made of a separately manufactured iron plate or steel plate is fixed to a heat radiating plate made of aluminum with a thermal head using screws or the like (for example, patents) (See sentence 1).
JP 2005-349721 A

  However, in the configuration described in Patent Document 1, it is necessary to manufacture the heat sink and the arm part separately, and to fix these heat sink and the arm part integrally using screws or the like. In addition to the increase in the number of parts, the number of assembling steps also increases, resulting in an increase in the cost of this type of image forming apparatus.

  The present invention has been made to solve the above-described problems, and reduces the number of parts made of an aluminum plate as a raw material of the frame that supports the thermal head as much as possible, and also reduces the number of parts and assembly man-hours. It is an object of the present invention to provide a thermal head type image forming apparatus, a frame body manufacturing method, and a blank used for a frame body that supports a thermal head.

  In order to achieve such an object, in the present invention, a thermal head having a head printing section for performing printing, a platen roller disposed opposite to the thermal head, and the thermal head being pressed and separated from the platen roller. In a thermal head type image forming apparatus having a frame body rotatably mounted, the frame body is made of a single aluminum plate, a cross beam portion on which the thermal head is mounted, and a thermal head A heat dissipating part for dissipating heat, and arms connected to both side ends of the cross beam part, and the arms are standing end parts connected to both side end parts of the cross beam part via bent parts, and It consists of a curved arm part connected to the end part and a shaft support part connected to the tip of this arm part, and the heat radiating part passes through the bent part from the horizontal girder part located on one side of the aluminum plate. Connected to the other side, and the arm is made of aluminum so that the apex part of the curved curve of the arm part is directed to the heat radiating part side through the cut and the arm part is located adjacent to the heat radiating part. A blank made of a flat frame body material is formed by punching from the pneum plate along the shape of the frame body, and the blank is bent by press work to form the frame body.

  According to this configuration, the apex portion of the curved curve of the arm portion of the arm is disposed adjacent to the inside of the aluminum plate via the cut in a state of entering the heat radiating portion. The lateral width of the aluminum plate as a raw material is reduced, the material dimensions can be reduced, and chips can be reduced. In addition, since the cross beam portion on which the thermal head is mounted, the arm, and the heat radiating portion are integrally formed, the number of parts and the number of assembly steps can be reduced. Further, since the frame body can be formed by stamping and bending by pressing, the manufacturing time can be shortened. As a result, the cost of this type of thermal head type image forming apparatus can be reduced.

  Further, in the present invention, a thermal head having a head printing section for performing printing, a platen roller disposed opposite to the thermal head, and the thermal head can be rotated so as to be pressed and separated from the platen roller. In a thermal head type image forming apparatus provided with a mounted frame body, the frame body is made of a single aluminum plate, and dissipates heat from the horizontal beam section to which the thermal head is mounted and the thermal head. The heat dissipating part and an arm connected to both side ends of the cross beam part are provided, and the arm is connected to the standing end part connected to the both side end parts of the cross beam part via a bent part, and the standing end part. A curved arm portion and a shaft support portion connected to the tip of the arm portion, and the heat radiating portion is connected to the other side of the aluminum plate via the bent portion from the transverse girder portion located on one side of the aluminum plate. In The arm is connected to the frame from the aluminum plate so that the apex portion of the curved curve of the arm part is directed to the heat radiating part side through the cut and the arm part is located adjacent to the heat radiating part. A blank made of a planar frame material is formed along the shape, and the blank is bent to form the frame.

  According to this configuration, according to this configuration, the apex portion of the curved portion of the arm portion of the arm is arranged adjacent to the inside of the aluminum plate through the cut in a state of entering the heat radiating portion. Since it is provided, the lateral width of the aluminum plate as a raw material is reduced, the material dimensions can be reduced, and chips can be reduced. In addition, since the cross beam portion on which the thermal head is mounted, the arm, and the heat radiating portion are integrally formed, the number of parts and the number of assembly steps can be reduced. As a result, the cost of this type of thermal head type image forming apparatus can be reduced.

  In the present invention, the cross beam portion is provided with fixing holes for fixing the thermal head on the left and right in the width direction of the image printed by the head printing unit, and these fixing holes are arranged in the width direction. One of the fixing holes that is long in the orthogonal conveying direction and that is wide in the width direction is formed.

  According to this configuration, since the fixing hole is formed as a long hole that is long in the transport direction orthogonal to the width direction, the attachment position of the head print portion of the thermal head can be finely adjusted. Further, since any one of the fixing holes is formed wide in the width direction, it is possible to absorb a dimensional error in the width direction of the screw hole of the thermal head, which is convenient.

  According to the present invention, in the method of manufacturing a frame that is rotatably mounted so that the thermal head is pressed and separated from the platen roller, the frame is made of a single aluminum plate, It has a cross beam part to which the head is mounted, a heat radiating part that dissipates the heat of the thermal head, and an arm that is connected to both side end parts of the cross beam part, and the arm is bent at both side end parts of the cross beam part. A rising end connected via the arm, a curved arm connected to the standing end, and a shaft support connected to the tip of the arm, and the heat dissipating part is one of the aluminum plates. The arm is connected to the other side through the bent part from the cross beam part located on the side of the arm, and the arm has the apex part of the curved curve of the arm part facing the heat radiating part side through the cut, and the arm part Is located adjacent to the heat sink As described above, along the shape of the frame from aluminum plate to form a blank comprising a flat frame material is punched out by press working, and thereafter, to form the frame body blank is bent by press working.

  According to this configuration, the frame body is punched out of one aluminum plate by press working along the shape of the frame body to form a blank made of a planar frame body material, and then the planar frame is formed. Since the blank made of the body material is bent and integrally formed by pressing, the frame can be manufactured very easily. As a result, the cost of this type of thermal head type image forming apparatus can be reduced.

  In the present invention, a fixing hole for fixing the thermal head to the cross beam portion is simultaneously formed at the time of punching by press working. According to this configuration, since the fixing hole for fixing the thermal head is formed at the same time when punching out by press working along the shape of the frame, it is possible to work in comparison with separately forming the fixing hole. In addition to shortening the process and the working time, the fixing hole is punched out in the same process, so that the dimensional accuracy can be improved, which is convenient.

  Further, in the present invention, it is composed of a single aluminum plate, is located on one side of the aluminum plate, and is attached to the other side of the transverse girder part to which the thermal head is mounted, and the bent part from the transverse girder part. A heat dissipating part that dissipates heat from the thermal head and an arm that is connected to both side ends of the cross beam part, and the arm is connected to both side end parts of the cross beam part via bent parts. And a curved arm part connected to the standing end part, and a shaft support part connected to the tip of the arm part. The arm is a vertex of the curved curve of the arm part. A planar frame material is formed through the cut so that the portion faces the heat radiating portion and the arm portion is positioned adjacent to the heat radiating portion.

  According to this configuration, the apex portion of the curved curve of the arm portion of the arm is disposed adjacent to the inside of the aluminum plate via the cut in a state of entering the heat radiating portion. The lateral width of the aluminum plate as a raw material is reduced, the material dimensions can be reduced, and chips can be reduced. As a result, it is possible to reduce the cost of the blank used for the frame that supports the thermal head.

  Further, in the present invention, the cross beam portion is provided with fixing holes for fixing the thermal head on the left and right sides in the width direction of the image printed by the head printing portion of the thermal head. One of the fixing holes that is long in the conveying direction orthogonal to the direction is formed wide in the width direction.

  According to this configuration, since the fixing hole is formed as a long hole that is long in the transport direction orthogonal to the width direction, the attachment position of the head print portion of the thermal head can be finely adjusted. Further, since any one of the fixing holes is formed wide in the width direction, it is possible to absorb a dimensional error in the width direction of the screw hole of the thermal head, which is convenient.

  According to the present invention, it is possible to obtain an image forming apparatus, a frame body manufacturing method, and a blank used for a frame body that supports a thermal head, in which the number of parts of the frame body that supports the thermal head is reduced and the manufacturing cost is reduced. it can.

  Hereinafter, an embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a conceptual diagram showing a configuration of a main part of a thermal head type image forming apparatus according to an embodiment of the present invention, and FIG. 2 is a perspective view showing a main part of the image forming apparatus shown in FIG. 3 is a perspective view of the frame of the image forming apparatus shown in FIG. 1, FIG. 4 is a top view of the frame shown in FIG. 3, FIG. 5 is a front view of the frame shown in FIG. 3, and FIG. It is a side view of the frame shown in FIG. FIG. 7 is a development view of an aluminum plate for forming the frame shown in FIG.

  As shown in FIG. 1, the thermal head type image forming apparatus 1 includes a paper feed cartridge 2 on which a recording paper P made of photographic paper or the like is placed, an ink ribbon cartridge 3 to which an ink ribbon 31 is attached, Sublimation dye applied to the ink ribbon 31 is sublimated, an image forming unit 4 for forming an image on the recording paper P, a paper transporting unit 5 for sequentially transporting the recording paper P to the image forming unit 4, and image formation The chassis 6 (see FIG. 2) on which the means 4 and the like are mounted and a drive motor (not shown) that drives the paper transport means 5, such as a stepping motor, a gear group including a drive gear, an intermediate gear, a cam gear, and the like. Drive means, and control means for performing various controls (not shown).

  In the recording paper P, a receiving layer made of a thermal transfer recording material is usually formed on a photographic paper base. As this thermal transfer recording material, a material obtained by adding an additive such as a lubricant to a polyester resin or polycarbonate resin is generally used.

  The paper feed cartridge 2 includes a placement portion 21 for placing and storing the recording paper P, and a lid portion 22. The paper feed cartridge 2 is placed on the placement portion 21 by the rotation operation of the paper feed roller 51. The recording paper P positioned at the top of the recording paper P is sequentially sent out in the paper feeding direction a (from left to right in FIG. 1: arrow a direction).

  The ink ribbon cartridge 3 includes a supply unit 3a having a supply bobbin (not shown) that is rotatably wound around the ink ribbon 31 and a take-up bobbin that is rotatably disposed and winds up the ink ribbon 31. It is comprised from the winding part 3b which has (not shown). The ink ribbon 31 is prepared by dissolving a sublimation dye with, for example, an acetate or a polyester solution, adding a dispersant to the colloidal solution, mixing the binder, and mixing the binder, For example, it is applied to paper or a film, and as is well known, a yellow printing area, a magenta printing area, a cyan printing area, and a surface protective layer area (OP layer) are provided. These yellow print area, magenta print area, cyan print area, and surface protective layer area have substantially the same dimensions as the maximum dimensions (width and length) of the transferred image. In addition, an identification unit is provided between the regions.

  As shown in FIG. 2, for example, the chassis 6 is formed by bending an iron plate or the like to form side surfaces 62 a and 62 b at both ends of the bottom surface 61. And both side surface parts 62a and 62b are comprised so that the below-mentioned press mechanism 43 may be supported so that rotation is possible.

  For example, the image forming unit 4 presses the thermal head 41 as the printing unit, the platen roller 42 facing the thermal head 41 through the ink ribbon 31, and presses the thermal head 41 against the platen roller 42 during printing. A pressing mechanism 43 is provided.

  Although not shown, the thermal head 41 has, for example, a head printing unit, and is mounted on a frame 7 described later so as to be rotatable so that the thermal head 41 is pressed and separated from the platen roller 42. The head printing section is a linear arrangement of heating elements over almost the same length as the width direction (main scanning direction) of the printed image. The heating elements convert electrical energy into thermal energy based on the print data. Convert. Each heating element is supplied with a color signal obtained by separating the image into three primary colors of yellow (Y), magenta (M), and cyan (C). Each heating element takes either a heat generation state or a non-heat generation state in accordance with the color signal, so that a sublimation dye in a portion of the sublimation dye applied to the ink ribbon 31 that faces the heat generation element that generates heat is removed. Sublimation or melt diffusion is performed and transferred onto the recording paper P. Therefore, the image is recorded line by line while moving the recording paper P relative to the thermal head 41 in the printing direction b (sub-scanning direction: right to left in FIG. 1: arrow b) in FIG. As a result, an image is formed.

  The platen roller 42 is rotatably supported by platen roller bearings (not shown) provided on both side surfaces 62 a and 62 b of the chassis 6 so as to face the thermal head 41.

  In the sheet conveying means 5, for example, a metal feed roller 52 that applies a conveying force to the recording sheet P is disposed on the upstream side in the printing direction b. Opposed to the feed roller 52, for example, a metal press roller 53 that presses the recording paper P against the feed roller 52 is disposed. The sheet conveying means 5 includes the above-described sheet feeding roller 51 and a conveying roller (not shown) provided as necessary.

  As shown in FIG. 2, the feed roller 52 is rotatably supported by a feed roller bearing 52a and is driven to rotate by the drive gear (not shown). The feed roller bearing 52a is supported by, for example, a bearing support hole (not shown) provided in the side surfaces 62a and 62b. Further, grip portions 52g that contact the vicinity of both left and right end portions of the recording paper P and act as slips are formed at left and right symmetrical positions on the surface of the feed roller 52 across the central axis of the paper feed path. The grip 52g may be formed with irregularities having a predetermined height by, for example, rolling (knurling) or the like. The recording paper P can be accurately conveyed by the grip portion 52g.

  The press roller 53 is a metal shaft, and its surface is finished smoothly. As shown in FIG. 2, the press roller 53 is rotatably supported by a press roller bearing 53 a and rotates following the rotation of the feed roller 52.

  With such a configuration, for example, the paper transport unit 5 corresponds to the sequential transfer of each color region so that superimposed color printing is performed by the ink ribbon 31 coated with three sublimation dyes. The feed roller 52 and the press roller 53 disposed opposite to the feed roller 52 repeat the reciprocating transfer in the longitudinal direction of the recording paper P, that is, the paper feeding direction a and the printing direction b (reverse direction). . Further, the control means (not shown) drives the drive means, and at the time of printing, the thermal head 41 attached to the frame body 7 is pressed against the platen roller 42 by the pressing mechanism 43, and at the time of paper feeding and paper ejection, Control is performed so that the above-mentioned pressing force by the pressing mechanism 43 is released and the thermal head 41 is retracted (state shown in FIG. 1).

  The recording paper P conveyed to the image forming unit 4 is once sent to the most downstream side in the paper feeding direction a. Thereafter, the recording paper P is conveyed from the right side to the left side, that is, in the printing direction b in FIG. 1 at substantially the same speed as the ink ribbon 31. In parallel with this, yellow image data is supplied to the thermal head 41 from a control means (not shown). Along with this, when the heating element of the head printing portion of the thermal head 41 generates heat, the sublimation dye in the portion facing it sublimates and is transferred (attached) to the surface of the recording paper P. A yellow (Y) image is formed. When the yellow image has been formed on the surface of the recording paper P, the thermal head 41 is retracted (raised) by the spring force of a torsion coil spring (not shown) by releasing the pressing force of the pressing mechanism 43.

  Thereafter, the control means controls the ink ribbon 31 to be wound up by an ink ribbon sensor or the like (not shown) until the leading end of the magenta printing area of the ink ribbon 31 is detected. Further, the sheet conveying means 5 is driven and conveyed in the paper feeding direction a which is opposite to the printing direction b until the leading edge of the recording paper P reaches the printing position. By this operation, a magenta image can be formed on the recording paper P. Thereafter, the above-described operation is repeated for each color of magenta, cyan, and the surface protective layer (colorless and transparent) to form a color image in the image area on the surface of the recording paper P, that is, to perform overlapping color printing. The thermal head 41 is initially lifted upward, and a sufficient gap is formed between the thermal head 41 and the platen roller 4 so as not to hinder the conveyance of the ink ribbon 31 and the recording paper P.

  When the color image has been formed on the recording paper P, the control means releases the pressing force of the pressing mechanism 43 against the thermal head 41 and reversely drives the stepping motor of the driving means so as to raise the thermal head 41. In addition, the paper conveying means 5 is controlled so that the recording paper P is discharged from the apparatus main body. For example, in FIG. 1, the paper discharge unit (not shown) provided on the upper portion of the lid portion 22 of the paper supply cartridge 2 is controlled. To the part.

  Thus, according to the present invention, as shown in FIGS. 3 to 7, the thermal head 41 is mounted on the frame body 7 so as to be rotatable so as to be pressed and separated from the platen roller 42. The frame body 7 includes a cross beam portion 71 to which the thermal head 41 is mounted, a heat radiation portion 72 that dissipates heat of the thermal head 41, and arms 73 that are connected to both side ends of the cross beam portion. Yes. The arm 73 includes a standing end portion 73a connected to both side ends of the cross beam portion 71 via a bent portion w1, a curved arm portion 73b connected to the standing end portion 73a, and the arm portion 73b. It is formed from a shaft support 73c connected to the tip. Further, the shaft support portion 73c is provided with a shaft hole 73d, and is supported by, for example, both side surface portions 62a and 62b of the chassis 6 by a support shaft (not shown). By this support shaft, the frame body 7 is configured to be rotatable so as to be pressed and separated from the platen roller 42 around the support shaft.

  The cross beam 71 is provided with fixing holes 71a and 71b for fixing the thermal head 41 on the left and right in the width direction of the image printed by the head printing unit (see FIG. 7: arrow X direction). The holes 71a and 71b are long holes that are long in the conveying direction (see FIG. 7: arrow Y direction) orthogonal to the width direction X of the image, and one of them, for example, a fixing hole on the right side in the illustrated example. 71a is formed wide in the width direction X. Further, in the cross beam 71, for example, a through hole 71c, a notch 71d, and the like are formed as necessary in order to avoid contact with a press spring (not shown) of the above-described pressing mechanism 43.

  As shown in FIG. 7, the frame body 7 is formed by punching out a single aluminum plate A1 along the shape of the desired frame body 7 by, for example, pressing, and cutting or penetrating a predetermined portion. A blank 70 made of a planar frame material, in which holes and further cutouts are formed, is formed by bending into a predetermined shape by, for example, pressing.

  Next, a blank 70 made of a planar frame material forming the frame 7 shown in FIG. 3 will be described. As shown in FIG. 7, the blank 70 is made of a single aluminum plate A1, and is provided with a cross beam portion 71 on one side x1 of the aluminum plate A1, and from this cross beam portion 71 via a bent portion w2. The heat radiation part 72 is connected toward the other side x2. Further, the standing end portion 73a of the arm 73 is connected to both side end portions of the cross beam portion 71 via the bent portion w1, and the apex portion T of the curved curve of the arm portion 73b is connected to the heat radiating portion 72 side through the cut z1. The arm 72 is provided so that the arm portion 73 b is positioned adjacent to the heat radiating portion 72. Further, in the illustrated example, the heat radiating portion 72 is bent by the bent portions w3 and w4, and the cross section is formed in a U shape. In the space formed by this U shape, for example, the ink ribbon cartridge 3 A supply unit 3a is provided.

  Next, the manufacturing method which manufactures the frame 7 as shown in FIG. 3 from the above-mentioned blank 70 is demonstrated. First, as shown in FIG. 7, a blank 70, which is a planar frame material, is formed by stamping from an aluminum plate A1 along the shape of a predetermined frame 7 by pressing. At the time of this punching, a cut z1, a shaft hole 73d, fixing holes 71a and 71b, a through hole 71c, and a notch 71d are simultaneously formed in a predetermined portion. Thereafter, in order to form the blank 70, which is a planar frame material, into a desired frame shape, the frame body 7 is formed by being bent by press working in a state of being placed on a mold or the like.

  In the present embodiment having the above-described configuration, the apex portion T of the curved curve of the arm portion 73b of the arm 73 enters the heat radiating portion 72 toward the inside of the aluminum plate A1 through the cut z1. Since it is disposed adjacent to the heat radiating portion 72, the lateral width H1 of the aluminum plate A1 as a raw material is, for example, about 20% smaller than the conventional example shown in FIG. Can be reduced and chips can be reduced. Moreover, since the cross beam portion 71 to which the thermal head 41 is mounted, the arm 73 and the heat radiating portion 72 are integrally formed, the number of parts and the number of assembly steps can be reduced. Further, since the frame body 7 can be formed by stamping and bending by press working, the manufacturing time can be shortened. As a result, the cost of this type of thermal head type image forming apparatus can be reduced.

  Further, since the fixing holes 71a and 71b are formed as long holes that are long in the transport direction orthogonal to the width direction, the attachment position of the head print portion of the thermal head 41 can be finely adjusted. Further, since any one of the fixing holes 71a and 71b is formed wide in the width direction, it is convenient because a dimensional error in the width direction of the screw hole of the thermal head 41 can be absorbed.

  Further, the frame body 7 is punched out of one aluminum plate A1 by press working along the shape of the frame body 7 to form a blank 70 which is a planar frame body material. Since the blank 70 which is a body material is bent and integrally formed by pressing, the frame body 7 can be manufactured very easily. As a result, the cost of this type of thermal head type image forming apparatus can be reduced.

  Further, since the fixing holes 71a and 71b for fixing the thermal head 41 are formed at the same time when punching out along the shape of the frame body 7 by pressing, the fixing holes 71a and 71b are separately formed. Compared to the above, the working process and working time can be shortened, and the fixing holes 71a and 71b are punched out in the same process, so that the dimensional accuracy can be improved, which is convenient.

  Furthermore, the apex portion T of the curved portion of the arm portion 73b of the arm 73 is adjacent to the heat radiating portion 72 via the cut line z1 in a state of entering the heat radiating portion 72 toward the inside of the aluminum plate A1. Since it is arranged, the lateral width H1 of the aluminum plate A1, which is a raw material, is reduced, the material dimensions can be reduced, and chips can be reduced. As a result, the cost of the blank 70 used for the frame body 7 that supports the thermal head 41 can be reduced.

  The above-described embodiment is a preferred embodiment of the present invention, but the present invention is not limited to this, and various modifications can be made without departing from the gist of the present invention.

  In the above-described embodiment, the thermal head type image forming apparatus in which the sublimable dye applied to the ink ribbon is sublimated and transferred onto the recording paper by the thermal head has been described. In a thermal head type image forming apparatus in which a thermal recording paper provided with a thermal coloring layer is used as the recording paper P, and the thermal recording paper is heated with a thermal head to perform color development recording. Of course, it may be applied.

1 is a conceptual diagram illustrating a configuration of a main part of a thermal head type image forming apparatus according to an embodiment of the present invention. FIG. 2 is a perspective view illustrating a main part of the image forming apparatus illustrated in FIG. 1. It is a perspective view of the frame of the image forming apparatus shown in FIG. It is a top view of the frame shown in FIG. It is a front view of the frame shown in FIG. It is a side view of the frame shown in FIG. It is an expanded view of the aluminum plate for forming the frame shown in FIG. It is a perspective view which shows the conventional frame. It is an expanded view of the aluminum plate for forming the frame shown in FIG.

Explanation of symbols

A1 Aluminum plate T Vertex part x1 One side x2 The other side w1 Bending part w2 Bending part z1 Cut 1 Thermal head type image forming apparatus 41 Thermal head 42 Platen roller 7 Frame body 70 Blank 71 Horizontal girder part 71a Fixing hole 71b Fixing hole 72 Heat radiation part 73 Arm 73a Standing end part 73b Arm part 73c Shaft support part

Claims (7)

A thermal head having a head printing section for performing printing, a platen roller disposed to face the thermal head, and a frame rotatably mounted so that the thermal head is pressed and separated from the platen roller A thermal head type image forming apparatus comprising:
The frame body is made of a single aluminum plate, and is connected to a cross beam portion to which the thermal head is mounted, a heat radiating portion for radiating heat of the thermal head, and both side end portions of the cross beam portion. An arm, and the arm includes an upright end portion connected to both side ends of the cross beam portion via a bent portion, a curved arm portion connected to the upright end portion, and an arm portion of the arm portion. The heat dissipation part is connected from the horizontal girder part located on one side of the aluminum plate toward the other side through a bent part, and the arm is composed of a shaft support part connected to the tip. From the aluminum plate to the shape of the frame so that the apex part of the curved curve of the arm part is directed to the heat radiating part side through a cut and the arm part is located adjacent to the heat radiating part. Punched by pressing To form a blank comprising a flat frame material, the blank thermal head type image forming apparatus is characterized in that molding the frame body is bent by press working. A thermal head having a head printing section for performing printing, a platen roller disposed to face the thermal head, and a frame rotatably mounted so that the thermal head is pressed and separated from the platen roller A thermal head type image forming apparatus comprising:
The frame body is made of a single aluminum plate, and is connected to a cross beam portion to which the thermal head is mounted, a heat radiating portion for radiating heat of the thermal head, and both side end portions of the cross beam portion. An arm, and the arm includes an upright end portion connected to both side ends of the cross beam portion via a bent portion, a curved arm portion connected to the upright end portion, and an arm portion of the arm portion. The heat dissipation part is connected from the horizontal girder part located on one side of the aluminum plate toward the other side through a bent part, and the arm is composed of a shaft support part connected to the tip. From the aluminum plate to the shape of the frame so that the apex part of the curved curve of the arm part is directed to the heat radiating part side through a cut and the arm part is located adjacent to the heat radiating part. Along the plane frame material To form a rank, a thermal head type image forming apparatus is characterized in that molding the frame body by bending the blank.   In the cross beam portion, fixing holes for fixing the thermal head are provided on the left and right sides of the width direction of the image printed by the head printing portion, and these fixing holes are in a conveying direction orthogonal to the width direction. 3. The thermal head type image forming according to claim 1, wherein one of the fixing holes is wide and the width of the fixing hole is wide in the width direction. 4. apparatus. In the manufacturing method of the frame body that is rotatably mounted so that the thermal head is pressed and separated from the platen roller,
The frame body is made of a single aluminum plate, and is connected to a cross beam portion to which the thermal head is mounted, a heat radiating portion for radiating heat of the thermal head, and both side end portions of the cross beam portion. An arm, and the arm includes an upright end portion connected to both side ends of the cross beam portion via a bent portion, a curved arm portion connected to the upright end portion, and an arm portion of the arm portion. The heat dissipation part is connected from the horizontal girder part located on one side of the aluminum plate toward the other side through a bent part, and the arm is composed of a shaft support part connected to the tip. From the aluminum plate to the shape of the frame so that the apex part of the curved curve of the arm part is directed to the heat radiating part side through a cut and the arm part is located adjacent to the heat radiating part. Punched by pressing Forming a blank comprising a flat frame material, thereafter, the manufacturing method of the frame, characterized in that the blank has been molded the frame body is bent by press working.   The frame manufacturing method according to claim 4, wherein a fixing hole for fixing the thermal head is simultaneously formed in the cross beam portion at the time of punching by the press working.   Consists of a single aluminum plate, located on one side of the aluminum plate, and connected to the other side of the horizontal girder part to which the thermal head is to be attached, and the bent part from the horizontal girder part. A heat dissipating part for dissipating heat of the thermal head, and arms connected to both side end parts of the cross beam part, and the arms are connected to both side end parts of the cross beam part via bent parts. And a curved arm portion connected to the standing end portion, and a shaft support portion connected to the tip of the arm portion, and the arm is a vertex of the curved curve of the arm portion. A frame for supporting a thermal head, characterized in that a planar frame material is formed through a cut so that a portion faces the heat radiating portion and an arm portion is positioned adjacent to the heat radiating portion. Blank used for the body.   The cross beam portion is provided with fixing holes for fixing the thermal head on the left and right sides in the width direction of the image printed by the head printing portion of the thermal head, and these fixing holes are orthogonal to the width direction. The frame for supporting a thermal head according to claim 6, wherein the frame is a long hole that is long in the conveying direction, and any one of the fixing holes is formed wide in the width direction. Blank used for.