JP2007145482A - Image forming device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image forming device capable of driving a pushing-up member, without complicating a structure of a paper feeding tray (a paper cassette). <P>SOLUTION: This image forming device has a device body for installing the paper cassette 6, a chassis 1 having a bottom surface 1c and a paper feeding roller 2 arranged in the device body, and the pushing-up member 9 installed on the bottom surface 1c of the chassis 1 and pressing paper 30 to the paper feeding roller 2. The pushing-up member 9 is integrally formed with a rotary shaft part 9m including a shaft part 9n and a nonslip off part 9o for preventing the pushing-up member 9 from slipping out in the upward direction. A fitting hole 1g rotatably supporting the pushing-up member 9 around the shaft part 9n of the rotary shaft part 9m, is arranged on the bottom surface 1c of the chassis 1, and the fitting hole 1g includes a fitting part 1h for fitting the rotary shaft part 9n of the pushing-up member 9 and a support part 1i formed so as to be connected to the fitting part 1h and rotatably supporting the pushing-up member 9 around the rotary shaft part 9m. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an image forming apparatus, and more particularly to an image forming apparatus provided with a push-up member for pressing paper in a paper cassette against a paper feed roller.

  2. Description of the Related Art Conventionally, a paper feeding device (feeding device) that feeds paper by raising a paper receiving portion and paper by a push-up member positioned on the lower surface of the paper receiving portion of the paper cassette on which the paper is placed, and pressing the paper against a paper feeding roller. An image forming apparatus including a paper tray is disclosed (for example, see Patent Document 1). In the image forming apparatus (laser printer) disclosed in Patent Document 1, a rotation shaft portion that is rotatably installed on the bottom surface of the paper feed tray and a rotation shaft portion are formed integrally with the rotation shaft portion. A push-up member having an arm portion formed to be orthogonal to the portion is provided, and the push-up member is configured to be rotated by a drive source installed in the printer main body. That is, in Patent Document 1, the push-up member is installed in a paper feed tray (paper cassette), while the drive source of the push-up member is installed in the printer main body. In order to transmit the driving force from the driving source to the push-up member, three gears are provided on the paper feed tray side.

  As an operation, a driving force from a driving source installed in the printer main body is transmitted to a push-up member installed in the paper feed tray, so that the tip end portion of the rotating arm portion of the push-up member becomes the bottom surface of the paper receiving portion. Abut. Thereby, the paper receiving portion and the paper are raised. The raised paper is pressed against the paper feed roller and taken into the printer body.

JP 2002-205830 A

  However, in the image forming apparatus disclosed in Patent Document 1, a push-up member and three gears for transmitting drive to the push-up member are installed in the paper feed tray, so the structure of the paper feed tray (paper cassette) There is a problem that becomes complicated.

  The present invention has been made to solve the above-described problems, and one object of the present invention is to drive the push-up member without complicating the structure of the paper feed tray (paper cassette). An image forming apparatus is provided.

  An image forming apparatus according to a first aspect of the present invention includes an apparatus main body on which a paper cassette for storing paper is mounted, a chassis having a bottom surface provided on the apparatus main body, and an apparatus main body that feeds paper. In an image forming apparatus including a paper feed roller that transports in a direction, a push-up member that presses the paper in the paper cassette against the paper feed roller is attached to the bottom surface of the chassis. And a rotation shaft portion including a retaining portion for preventing the push-up member from slipping upward. The pivot shaft portion of the push-up member is retained on the bottom surface of the chassis. And a fitting hole for supporting the push-up member so as to be rotatable about the shaft portion of the rotation shaft portion, and the fitting hole is configured to rotate the push-up member. A long hole-like fitting portion for fitting the shaft portion; A long hole-shaped support portion that is formed so as to be connected to the fitting portion and supports the push-up member so as to be rotatable about the rotation shaft portion. And the one side where the convex portion is provided integrally and the other side where the concave portion is provided integrally at a position corresponding to the convex portion, and the shaft portion of the push-up member is one side of the support portion of the fitting hole The convex portion and the concave portion on the other side are supported by a portion other than the concave portion, and the convex portion and the concave portion are formed in a trapezoidal shape when seen in a plan view, and the length of the convex portion in the direction perpendicular to the paper feeding direction is The length of the concave portion in the paper feeding direction is smaller than the length of the concave portion in the paper feeding direction and in plan view, and the length of the concave portion in the paper feeding direction is longer than the length of the portion protruding in the paper feeding direction of the retaining portion of the push-up member. The length in the paper feeding direction of the fitting portion of the fitting hole of the chassis is small and seen in plan view, and the length of the retaining portion of the rotation shaft portion of the push-up member is The pivot shaft part of the push-up member is larger than the length in the direction, and after being inserted into the fitting part, it is moved horizontally from the fitting part to the support part, so that it can be pivoted on the support part. Is done.

  In the image forming apparatus according to the first aspect, as described above, the push-up member for pressing the sheet against the sheet feeding roller is attached to the chassis having the bottom surface provided in the apparatus main body to which the sheet cassette is mounted. Therefore, unlike the case where the push-up member is attached to the bottom surface of the paper cassette, it is possible to suppress the complicated structure of the paper cassette. As a result, the push-up member can be driven without complicating the structure of the paper cassette. Further, the fitting hole of the chassis is formed so as to be connected to the fitting portion having a long hole shape for fitting the rotation shaft portion of the push-up member, and the push-up member is attached to the rotation shaft portion. A long hole-like support part for pivotally supporting the center, and the long hole-like support part corresponds to the one side on which the convex part is integrally provided and the convex part. Including the other side on which the concave portion is integrally provided at the position, and the shaft portion of the push-up member excludes the convex portion on one side of the support portion of the fitting hole of the chassis and the concave portion on the other side. By configuring so as to be supported by the part, the distance between the convex part on one side and the part excluding the concave part on the other side may be made to correspond to the shaft part of the push-up member. Since it is not necessary to make the space between the concave portion on the other side correspond to the thickness of the shaft portion of the push-up member, the support portion On the other hand the distance between the convex portion and the other side of the recess of the edges may be greater than the thickness of the shaft portion of the push-up member. Thus, when the fitting hole having the fitting portion and the support portion is formed in the chassis by punching with a press, the thickness of the punch is larger than the thickness of the shaft portion of the push-up member. Since it only needs to be formed in accordance with the distance from the recess, even when the thickness of the shaft portion of the push-up member is reduced, it is not necessary to reduce the thickness of the punch. For this reason, it is possible to prevent the punch from being broken even when the thickness of the push-up member is reduced. In addition, the convex and concave portions of the support portion of the fitting hole of the chassis are formed in a trapezoidal shape when seen in a plan view, so that the planar inclination angle is larger than when the convex and concave portions are formed in a rectangular shape. Becomes smaller. Accordingly, it is possible to make it difficult to reduce the corners of the punch when forming the support portion, and therefore it is possible to reduce the number of times of maintenance and replacement of the punch. Further, when viewed in a plan view, the length of the convex portion in the direction perpendicular to the paper feeding direction is formed to be smaller than the length of the concave portion in the paper feeding direction and in the vertical direction so that the gap between the convex portion and the concave portion of the support portion is reduced. Can be easily made larger than the thickness of the shaft portion of the push-up member. In addition, the concave portion is included by making the length of the concave portion in the paper feeding direction smaller than the length of the portion protruding in the paper feeding direction of the retaining portion of the rotation shaft portion of the push-up member in plan view. A portion protruding in the paper feeding direction of the retaining portion of the push-up member can be pressed all over the other side. Thereby, it can suppress that a pushing-up member remove | deviates from the support part of a fitting hole. Further, the length of the fitting portion of the fitting hole of the chassis in the paper feeding direction is made larger than the length of the retaining portion of the rotation shaft portion of the lifting member in the paper feeding direction, so that the pushing member can be easily Can be mounted in the fitting hole of the chassis. Further, after inserting the pivot shaft portion of the push-up member into the fitting portion, by moving in a horizontal direction from the fitting portion to the support portion, it can be easily mounted on the support portion in a rotatable manner, The push-up member can be rotatably mounted on the chassis support.

  An image forming apparatus according to a second aspect of the present invention is provided with an apparatus main body in which a paper cassette for storing paper is mounted, a chassis having a bottom surface provided in the apparatus main body, and provided in the apparatus main body to feed paper. A paper feed roller that transports in the direction and a push-up member that is attached to the bottom surface of the chassis and presses the paper in the paper cassette against the paper feed roller. The push-up member includes a shaft portion and a push-up member in the upward direction. The rotation shaft portion including the retaining portion for preventing the shaft from coming off is integrally formed, and the retaining portion and the shaft portion of the rotation shaft portion of the push-up member are fitted into the bottom surface of the chassis. In addition, a fitting hole that supports the push-up member so as to be rotatable about the shaft portion of the rotation shaft portion is provided, and the fitting hole is for fitting the rotation shaft portion of the push-up member. So that it is connected to the long hole-like fitting part and the fitting part And a long hole-shaped support portion for supporting the push-up member so as to be rotatable about the rotation shaft portion. The long hole-shaped support portion of the fitting hole is integrally provided with a convex portion. And the other side on which the concave portion is integrally provided at a position corresponding to the convex portion, and the shaft portion of the push-up member includes the convex portion on one side of the support portion of the fitting hole and the other side. It is supported by parts other than the recessed part.

  In the image forming apparatus according to the second aspect, as described above, the push-up member for pressing the paper against the paper feed roller is attached to the chassis having the bottom surface provided in the apparatus main body to which the paper cassette is mounted. Therefore, unlike the case where the push-up member is attached to the bottom surface of the paper cassette, it is possible to suppress the complicated structure of the paper cassette. As a result, the push-up member can be driven without complicating the structure of the paper cassette. Further, the fitting hole of the chassis is formed so as to be connected to the fitting portion having a long hole shape for fitting the rotation shaft portion of the push-up member, and the push-up member is attached to the rotation shaft portion. A long hole-like support part for pivotally supporting the center, and the long hole-like support part corresponds to one side on which the convex part is integrally provided and the convex part. Including the other side on which the concave portion is integrally provided at the position, and the shaft portion of the push-up member excludes the convex portion on one side of the support portion of the fitting hole of the chassis and the concave portion on the other side. By configuring so as to be supported by the part, the distance between the convex part on one side and the part excluding the concave part on the other side may be made to correspond to the shaft part of the push-up member. Since it is not necessary to make the space between the concave portion on the other side correspond to the thickness of the shaft portion of the push-up member, the support portion On the other hand the distance between the convex portion and the other side of the recess of the edges may be greater than the thickness of the shaft portion of the push-up member. Thus, when the fitting hole having the fitting portion and the support portion is formed in the chassis by punching with a press, the thickness of the punch is larger than the thickness of the shaft portion of the push-up member. Since it only needs to be formed in accordance with the distance from the recess, even when the thickness of the shaft portion of the push-up member is reduced, it is not necessary to reduce the thickness of the punch. For this reason, it is possible to prevent the punch from being broken even when the thickness of the push-up member is reduced.

  In the image forming apparatus according to the second aspect, preferably, the convex portion and the concave portion are formed in a trapezoidal shape when seen in a plan view. If comprised in this way, a planar inclination | tilt angle becomes small compared with the case where a convex part and a recessed part are formed in rectangular shape. Accordingly, it is possible to make it difficult to reduce the corner portion of the punch when forming the support portion, and therefore it is possible to reduce the number of times of maintenance and replacement of the punch.

  In the image forming apparatus according to the second aspect, preferably, the length of the convex portion in the direction perpendicular to the paper feeding direction is smaller than the length of the concave portion in the direction perpendicular to the paper feeding direction as viewed in a plan view. If comprised in this way, the space | interval between the convex part of a support part and a recessed part can be easily made larger than the thickness of the axial part of a pushing-up member.

  In the image forming apparatus according to the second aspect, preferably, the length of the concave portion in the paper feeding direction is smaller than the length of the portion protruding in the paper feeding direction of the retaining portion of the push-up member in a plan view. . If comprised in this way, the retaining part of a raising member can be pressed down by the whole other side including a recessed part. Thereby, it can suppress that a pushing-up member remove | deviates from the support part of a fitting hole.

  In the image forming apparatus according to the second aspect described above, preferably, the length of the fitting portion of the fitting hole of the chassis in the paper feeding direction is a retaining portion of the rotating shaft portion of the push-up member when viewed in plan. It is larger than the length in the paper feeding direction. If comprised in this way, the rotating shaft part of a raising member can be easily mounted in the fitting hole of a chassis.

  In the image forming apparatus according to the second aspect, preferably, the rotation shaft portion of the push-up member is inserted into the fitting portion and then moved in the horizontal direction from the fitting portion to the support portion, thereby supporting It is rotatably mounted on the part. If comprised in this way, a pushing-up member can be easily attached to the support part of the fitting hole of a chassis so that rotation is possible.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a perspective view showing the overall structure of a thermal transfer printer according to an embodiment of the present invention. 2, 3 and 4 are diagrams showing details of the structure of the thermal transfer printer according to the embodiment of the present invention shown in FIG. 5 to 8 are views for explaining details of the fitting hole of the chassis of the thermal transfer printer according to the embodiment of the present invention. 9 to 14 are diagrams for explaining the details of the push-up member of the thermal transfer printer according to the embodiment of the present invention. FIG. 15 is a view for explaining a method for forming a fitting hole of a chassis of a thermal transfer printer according to an embodiment of the present invention. A structure of a thermal transfer printer according to an embodiment of the present invention will be described with reference to FIGS. In this embodiment, a thermal transfer printer will be described as an example of the image forming apparatus of the present invention.

  As shown in FIGS. 1 to 4, the thermal transfer printer according to the embodiment of the present invention includes a sheet metal chassis 1 provided in a main body of a device to which a paper cassette 6 containing paper 30 is mounted, and a paper 30. A rubber paper feed roller 2 for feeding paper, a paper feed roller shaft 3 to which the paper feed roller 2 is attached, a paper feed roller gear 4 for rotating the paper feed roller shaft 3, and a paper feed roller bearing 5 The platen roller 7 to which the paper 30 is pressed at the time of printing, the platen roller bearing 8, the metal (sheet metal) push-up member 9 for pressing the paper against the paper feed roller 2, the drive gear 10, and the drive gear A motor 11 (see FIG. 3) that functions as a driving source for driving the motor 10, an intermediate gear 12 (see FIG. 3) for transmitting a driving force from the motor 11 to the driving gear 10, and a paper feed roller 2. Drive to drive A motor 13 (see FIG. 3) functioning as a source, a plurality of intermediate gears 14 (see FIG. 3) for transmitting the driving force from the motor 13 to the paper feed roller gear 4, and the metal to which the motor 11 and the motor 13 are attached A motor bracket 15 made of heat, a thermal head 16, and a torsion coil spring 17 that urges the thermal head 16 in a direction away from the platen roller 7 are provided.

  As shown in FIGS. 1 to 4, the chassis 1 has one side surface 1 a to which the motor bracket 15 is attached, the other side surface 1 b, and a bottom surface 1 c that connects the one side surface 1 a and the other side surface 1 b. In addition, an ink sheet cartridge insertion hole 1d for attaching an ink sheet cartridge (not shown) containing an ink sheet is provided on the other side surface 1b of the chassis 1. Further, as shown in FIG. 4, a feed roller bearing mounting hole 1 e and a platen roller bearing mounting hole 1 f are provided on one side surface 1 a and the other side surface 1 b of the chassis 1. A paper feed roller bearing 5 that rotatably supports both ends of the paper feed roller 2 is attached to the paper feed roller bearing mounting holes 1e on the one side surface 1a and the other side surface 1b of the chassis 1. Further, platen roller bearings 8 that rotatably support both end portions of the platen roller 7 are attached to the platen roller bearing attachment holes 1f on the one side surface 1a and the other side surface 1b of the chassis 1.

  Here, in this embodiment, as shown in FIGS. 3 and 4, a push-up member 9 is rotatably attached to the bottom surface 1c of the chassis 1 provided in the apparatus main body. Specifically, the bottom surface 1c of the chassis 1 is provided with fitting holes 1g and 1o into which rotation shaft portions 9m and 9p of a push-up member 9 described later are fitted, respectively. Further, as shown in FIG. 5, the fitting hole 1g is provided with a long hole-like fitting portion 1h. The fitting portion 1h has a length L1 in the paper feeding direction (A direction) when seen in a plan view. The fitting hole 1g is provided with a long hole-like support portion 1i so as to be connected to the fitting portion 1h. The support part 1i has one side 1k on which the convex part 1j is integrally provided, and the other side 1m in which the concave part 11 is integrally provided at a position corresponding to the convex part 1j. The convex portion 1j and the concave portion 11 are formed in a trapezoidal shape when viewed in plan, and the length W1 of the convex portion 1j in the direction perpendicular to the paper feeding direction (B direction) is the corresponding length W2 of the concave portion 11. Smaller than. Further, the corners of the convex portion 1j and the concave portion 11 are formed in a square shape. Moreover, it forms so that the space | interval between the opposing sides between the one side 1k and the other side 1m in the support part 1j may become length L2. This length L2 is formed to be larger than the thickness t of a shaft portion 9n of the push-up member 9 described later.

  As shown in FIGS. 6 and 7, when viewed in plan, the length L3 of the recess 11 in the paper feeding direction (A direction) is the paper feeding direction (see FIG. 6) of the retaining portion 9o of the push-up member 9 described later. It is smaller than the length L6 (see FIG. 7) of the portion protruding in the (A direction). Further, as viewed in a plan view, the length L1 of the fitting portion 1h of the fitting hole 1g in the paper feeding direction (A direction) is larger than the length L4 of the retaining member 9o of the push-up member 9 in the paper feeding direction. Thereby, it is possible to fit in the fitting portion 1h from the upper side to the lower side in the horizontal state without inclining the rotation shaft portion 9m. Further, as shown in FIGS. 7 and 8, the interval L5 in the sheet feeding direction (A direction) between the convex portion 1j of the support portion 1i of the fitting hole 1g and the portion 1n excluding the concave portion 11 of the other side 1m is In order to insert the shaft portion 9n, the shaft portion 9n of the push-up member 9 is formed to be slightly larger than the thickness t.

  In the present embodiment, as shown in FIG. 8, the shaft portion 9n of the push-up member 9 is supported by a portion 1n excluding the convex portion 1j and the concave portion 11 of the other side 1m. In such a configuration, for example, even when the thickness t of the shaft portion 9n of the push-up member 9 is reduced, the supply of the convex portion 1j is such that the interval L5 is slightly larger than the thickness t of the shaft portion 9n of the push-up member 9. The length L7 in the paper direction (A direction) is set, and the length L3 of the concave portion in the paper feeding direction (A direction) is changed by an amount corresponding to the change in the length L7 of the convex portion 1j in the paper feeding direction (A direction). Thus, the interval L5 can be changed without changing the interval L2. In addition, as shown in FIG. 4, the fitting hole 1o has the same shape as the fitting hole 1g, and has the fitting part 1p and the support part 1q. The relationship between the rotation shaft portion 9p of the push-up member 9 and the fitting hole 1o is the same as the relationship between the rotation shaft portion 9m and the fitting hole 1g described above.

  9 to 14, the metal push-up member 9 pushes up the chassis mounting portion 9a attached to the chassis 1 and the lower surface of the pressing plate 6a of the paper cassette 6, thereby causing the paper 30 (FIG. (Not shown) has a push-up portion 9b that presses the paper feed roller 2, and a chassis spring 9c and a coil spring 9c that holds the push-up portion 9b with a predetermined tension. The chassis mounting portion 9a includes a coil spring mounting portion 9e, an engagement hole 9f that engages with the push-up portion 9b, an insertion hole 9g into which the platen roller bearing 8 is inserted, and a cam groove 10a of the drive gear 10 (FIGS. 1 and 2), and a cam engaging portion 9h. As shown in FIGS. 2 and 5, the insertion hole 9 g of the push-up member 9 has an inner diameter larger than the outer diameter of the platen roller bearing 8 that does not contact the platen roller bearing 8 when the push-up member 9 rotates. Have Moreover, as shown in FIGS. 9-14, the chassis mounting part 9a further has the rotating shaft part 9m engaged with the fitting hole 1g. The rotating shaft portion 9m includes a shaft portion 9n and a retaining portion 9o for preventing the push-up member 9 from coming off upward. The shaft portion 9n is formed to be bent at a right angle (vertical) with respect to the horizontal surface of the push-up member 9. The retaining portion 9o is bent at a right angle with respect to the vertical surface of the shaft portion 9n, protrudes from the push-up member 9, and extends in parallel with the horizontal surface of the push-up member 9. Further, as shown in FIGS. 9, 10 and 12, the chassis mounting portion 9a has a rotation shaft portion 9p having the same shape as the rotation shaft portion 9m with a predetermined distance in the B direction from the rotation shaft portion 9m. The rotation shaft portion 9p has a shaft portion 9q and a retaining portion 9r. The rotation shaft portion 9p is fitted into the fitting hole 1o in the present embodiment.

  The push-up portion 9b includes an engaging portion 9i that engages with the chassis mounting portion 9a, a coil spring mounting portion 9k, and a pressing portion 9l that presses the lower surface of the pressing plate 6a. As shown in FIG. 8, the engaging portion 9i of the push-up portion 9b is rotatably engaged with the engaging hole 9f of the chassis mounting portion 9a. Further, one end 9d of the coil spring 9c is attached to the coil spring attachment portion 9e of the chassis attachment portion 9a, and the other end 9j of the coil spring 9c is attached to the coil spring attachment portion 9k of the push-up portion 9b. Such a structure in which the chassis mounting portion 9a and the push-up portion 9b are connected by the coil spring 9c reduces the load on the push-up member 9 by absorbing the load applied to the push-up portion 9b by the weight of the paper 30 by the coil spring 9c. It has a function.

  Here, in this embodiment, as shown in FIGS. 2 and 3, the drive gear 10 is attached to one side surface 1 a of the chassis 1. A cam groove 10 a with which the cam engaging portion 9 h of the push-up member 9 abuts is provided on the one side surface 1 a side (back surface side) of the drive gear 10. The cam groove 10a has a circular groove portion 10b and a concave groove portion 10c. When the drive gear 10 rotates in a state where the cam engaging portion 9h of the push-up member 9 is engaged with the circular groove portion 10b and the concave groove portion 10c, the push-up member 9 is centered on the rotating shaft portions 9m and 9p. To turn. As shown in FIG. 3, the motor 11 has a motor gear 11a. As shown in FIG. 3, the intermediate gear 12 is attached to one side surface 1a of the chassis 1, and has a large-diameter gear portion 12a and a small-diameter gear portion 12b. The motor gear 11 a and the large diameter gear portion 12 a of the intermediate gear 12 are engaged, and the small diameter gear portion 12 b of the intermediate gear 12 is engaged with the drive gear 10. For this reason, the driving force from the motor 11 is transmitted to the push-up member 9 through three gears of the motor gear 11 a, the intermediate gear 12, and the driving gear 10. The thermal head 16 has a function of rotating about the support shaft 16a and printing on the paper 30 (see FIG. 20).

  Further, as shown in FIG. 2, a pressing plate 6 a is provided at a predetermined position of the paper cassette 6. The pressing plate 6a is formed to be rotatable around a fulcrum portion 6b. The pressing plate 6 a is formed so as to press the paper 30 against the paper feed roller 2 by being pushed up by the pressing portion 9 l of the push-up member 9. The paper feed roller 2 is disposed above the pressing plate 6 a of the paper cassette 6. The paper feed roller 2 is configured to convey the paper 30 (see FIG. 20) in the paper feed direction (the direction of arrow A in FIG. 2) by rotating. The rubber paper feed roller 2 is attached in the vicinity of the center of the paper feed roller shaft 3. Both ends of the paper feed roller shaft 3 are rotatably supported by paper feed roller bearings 5 attached to one side surface 1a and the other side surface 1b of the chassis 1. A paper feed roller gear 4 is attached to the end of the paper feed roller shaft 3 on the side surface 1a so as not to idle. As shown in FIG. 3, an intermediate gear 14 is engaged with the paper feed roller gear 4. The plurality of intermediate gears 14 are arranged to engage with the motor 13.

  Next, with reference to FIG. 15, the formation method of the fitting holes 1g and 1o of the chassis 1 in this embodiment is demonstrated. First, a sheet metal to be the chassis 1 is placed on the lower mold 50. By pressing the upper die 60 having the punch 61 having the shape of the fitting holes 1g and 1o on the bottom surface 61a against the sheet metal, the fitting holes 1g and 1o are formed in the portion that becomes the bottom surface 1c of the chassis 1. . Moreover, in this embodiment, the thickness of the part with respect to the support part 1i (1q) of the fitting hole 1g (1o) of the chassis 1 of the punch part 61 is larger than the thickness of the axial part 9n (9q) of the pushing-up member 9. Is set to L2.

  Next, with reference to FIGS. 4 and 16 to 19, a method for attaching the push-up member of the thermal transfer printer according to the present embodiment will be described.

  First, as shown in FIGS. 16 and 17, the push-up member 9 is disposed above the bottom surface 1 c of the chassis 1. Next, by moving the push-up member 9 from the horizontal state vertically downward (in the direction of arrow Z in FIG. 20), the rotation shaft portions 9m and 9p of the push-up member 9 are respectively fitted into the fitting portions 1h of the fitting holes 1g. And it fits in the fitting part 1p of the fitting hole 1o. As a result, the state shown in FIG. 18 is obtained. Next, from the state of FIG. 18, the pivot shafts 9 m and 9 p of the push-up member 9 are moved in the arrow Y direction (horizontal direction) until they contact the bottom surface 1 c of the chassis 1. As a result, the state shown in FIG. 19 is obtained. Further, from the fitting portion 1h and the fitting portion 1p to the support portions 1i and 1q having a length L5 (see FIG. 7) larger than the thickness t of the shaft portion 9n and the shaft portion 9q of the push-up member 9, the arrows in FIG. It moves in the X direction (horizontal direction), and the pivot shaft portion 9m and the pivot shaft portion 9p of the push-up member 9 are rotatably mounted on the support portion 1i and the support portion 1q.

  Next, the sheet feeding operation of the thermal transfer printer according to the present embodiment will be described with reference to FIGS.

  First, as shown in FIG. 20, when the small-diameter gear 12b of the intermediate gear 12 rotates in the direction of arrow C in FIGS. 20 and 21 by the driving force from the motor 12 (see FIG. 3), the driving gear 10 Rotate in the D direction. Accordingly, the cam engaging portion 9h of the push-up member 9 is engaged with the concave groove portion 10c of the cam groove 10a of the drive gear 10 from the state of being engaged with the circular groove portion 10b of the cam groove 10a of the drive gear 10. become. Thus, as shown in FIG. 21, the push-up member 9 rotates in the direction of arrow E with the rotation shaft portion 9m and the rotation shaft portion 9p (see FIG. 3) as the rotation center. The sheet 30 supported by the pressing plate 6a of the sheet cassette 6 is pressed against the sheet feeding roller 2 by the pressing unit 9l. Next, as shown in FIG. 3, the driving force of the motor 14 is transmitted to the paper feed roller gear 4 via the plurality of intermediate gears 14. Accordingly, as shown in FIG. 21, the paper feed roller shaft 3 and the paper feed roller 2 rotate in the F direction, so that the paper 30 is conveyed in the A direction.

  In the present embodiment, as described above, the push-up member 9 for pressing the paper 30 against the paper feed roller 2 is attached to the chassis 1 having the bottom surface 1c provided in the apparatus main body to which the paper cassette 6 is mounted. Thus, unlike the case where the push-up member 9 is attached to the paper cassette 6, it is possible to suppress the structure of the paper cassette 6 from becoming complicated. Thus, the push-up member 9 can be driven without complicating the structure of the paper cassette 6.

  Further, in the present embodiment, the fitting hole 1g of the chassis 1 is connected to the fitting part 1h having a long hole shape for fitting the rotation shaft part 9m of the lifting member 9 and the fitting part 1h. And a long hole-shaped support portion 1i for supporting the push-up member 9 so as to be rotatable about the rotation shaft portion 9m. 1j is formed so as to include one side 1k provided integrally and the other side 1m provided with a concave portion 1l integrally at a position corresponding to the convex portion 1j, and the shaft portion 9n of the push-up member 9 is The support 1i of the support portion 1i of the fitting hole 1g of the chassis 1 is supported by the convex portion 1j on one side 1k and the portion 1n excluding the concave portion 11 on the other side 1m. Press the distance L5 in the sheet feeding direction between the other side 1m excluding the recess 1l and the portion 1n The distance L2 between the convex portion 1j on one side 1k of the support member 1i and the concave portion 11 on the other side 1m may correspond to the thickness t of the shaft portion 9n of the push-up member 9. Since there is no need, the distance L2 between the convex portion 1j on one side 1k of the support portion 1i and the concave portion 11 on the other side 1m can be made larger than the thickness t of the shaft portion 9n of the push-up member 9. Thereby, when forming the fitting hole 1g which has the fitting part 1h and the support part 1i in the chassis 1 by punching with a press machine, the thickness of the punch is made larger than the thickness t of the shaft part 9n of the push-up member 9. Since it only needs to be formed in accordance with the distance L2 between the convex part 1j and the concave part 11 of the large support part 1i, it is necessary to reduce the thickness of the punch even when the thickness t of the shaft part 9n of the push-up member 9 is reduced. Absent. For this reason, even when the thickness of the pushing-up member 9 becomes small, it can suppress that a punch breaks.

  Moreover, in this embodiment, the convex part 1j and the concave part 11 are formed in a rectangular shape by forming the convex part 1j and the concave part 11 of the supporting part 1i of the fitting hole 1g of the chassis 1 in a trapezoidal shape when seen in a plan view. The planar inclination angle is smaller than that in the case of forming in the above. Accordingly, it is possible to make it difficult to reduce the corner portion of the punch when forming the support portion 1i, and therefore it is possible to reduce the number of times of maintenance and replacement of the punch.

  In the present embodiment, the length W1 in the direction perpendicular to the paper feeding direction of the convex portion 1j is smaller than the length W2 in the direction perpendicular to the paper feeding direction of the concave portion 1l in plan view. The distance L2 between the convex portion 1j and the concave portion 11 of the support portion 1i can be easily made larger than the thickness t of the shaft portion 9n of the push-up member 9.

  Further, in the present embodiment, the length L3 of the recess 11 in the sheet feeding direction is made smaller than the length L6 of the portion protruding in the sheet feeding direction of the retaining portion 9o of the push-up member 9, so that the recess 11 is formed. The retaining portion 9o of the push-up member 9 can be pressed by the entire other side 1m. Thereby, it can suppress that the pushing-up member 9 remove | deviates from the support part 1i of the fitting hole 1g.

  In this embodiment, the length L1 in the sheet feeding direction of the fitting portion 1h of the fitting hole 1g of the chassis 1 is set to the length in the sheet feeding direction of the retaining portion 9o of the rotation shaft portion 9m of the push-up member 9. By making it larger than the length L4, the rotation shaft portion 9m of the push-up member 9 can be easily mounted in the fitting hole 1g of the chassis 1.

  Moreover, in this embodiment, after rotating shaft part 9m of push-up member 9 is inserted in fitting part 1h, it moves to supporting part 1i by moving horizontally from fitting part 1h to supporting part 1i. By movably mounting, the push-up member 9 can be easily mounted on the support portion 1i of the fitting hole 1g of the chassis 1 so as to be rotatable.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is shown not by the above description of the embodiment but by the scope of claims for patent, and all modifications within the meaning and scope equivalent to the scope of claims for patent are included.

  For example, in the above-described embodiment, the thermal transfer printer is shown as an example of the image forming apparatus. However, the present invention is not limited to this, and other image forming apparatuses such as an inkjet printer and a laser printer other than the thermal transfer printer may be used as long as the image forming apparatus. It is also applicable to the device.

  Moreover, in the said embodiment, although the example which provided each two rotation shaft parts and fitting holes was shown, this invention is not restricted to this, A rotation shaft part and a fitting hole, An example in which one each or three or more are provided may be shown.

  Moreover, although the example which forms the convex part and recessed part of an insertion part in trapezoid shape was shown in the said embodiment, this invention is not restricted to this, For example, you may form in rectangular shape other than trapezoid shape.

  Moreover, although the example which transmits the driving force of a motor to a pushing-up member via a some gear was shown in the said embodiment, in this invention, you may drive directly with a motor not only in this.

  Moreover, in the said embodiment, although the example which forms the convex part of a support part and the corner | angular part of a recessed part in a square was shown, this invention is not limited to this, The corner | angular part of a convex part and a recessed part is formed in a round shape. Also good. If comprised in this way, the corner | angular part of a support part will decrease. As a result, when the support portion is formed, the reduction in the corner portion of the punch can be reduced as compared with the case where the support portion is formed in a square shape, so that the number of times of maintenance and replacement of the punch can be reduced.

1 is a perspective view showing an overall configuration of a thermal transfer printer according to an embodiment of the present invention. FIG. 2 is a perspective view in which a print head and a platen roller are removed from FIG. 1. FIG. 3 is a plan view corresponding to FIG. 2. It is a perspective view which shows the positional relationship of the chassis by one Embodiment of this invention, a pushing-up member, and a fitting hole. It is a top view which shows the detail of the fitting hole by one Embodiment of this invention. It is an enlarged plan view showing the case where the rotation shaft portion of the push-up member is attached to the fitting hole according to the embodiment of the present invention. It is sectional drawing along the 200-200 line | wire of FIG. It is sectional drawing in alignment with 300-300 change of FIG. It is a perspective view which shows the whole structure of the raising member by one Embodiment of this invention. FIG. 10 is a plan view corresponding to FIG. 9. It is sectional drawing along the 400-400 line of FIG. It is a disassembled perspective view of the raising member by one Embodiment of this invention. FIG. 11 is a cross-sectional view taken along line 400-400 in FIG. 10 of the chassis mounting portion of the push-up member according to the embodiment of the present invention. FIG. 11 is a cross-sectional view taken along the line 400-400 in FIG. 10 of the push-up portion of the push-up member according to the embodiment of the present invention. It is the schematic which shows the punching process by a punch. It is a perspective view for demonstrating the procedure which mounts a pushing-up member in the fitting hole by one Embodiment of this invention. It is sectional drawing in alignment with the 500-500 line | wire of FIG. 16 in the process X of FIG. It is sectional drawing in alignment with the 500-500 line | wire of FIG. 16 in the process Y of FIG. It is sectional drawing in alignment with the 500-500 line | wire of FIG. 16 in the process Z of FIG. FIG. 3 is a cross-sectional view taken along line 100-100 in FIG. FIG. 3 is a cross-sectional view taken along the line 100-100 in FIG. 2 illustrating a paper feeding state of a paper feeding operation of the thermal transfer printer according to the embodiment of the present invention.

Explanation of symbols

1 Chassis 1c Bottom 1g, 1o Fitting hole
1h, 1p fitting portion 1i, 1q support portion 1j convex portion 1k one side 1l concave portion 1m other side 2 paper feed roller 6 paper cassette 9 push-up member 9m, 9p rotating shaft portion 9n shaft portion 9o retaining portion
10 Drive gear
10a Cam groove 11 Motor 11a Motor gear 12 Intermediate gear 30 Paper

Claims (6)

An apparatus main body on which a paper cassette for storing paper is mounted, a chassis having a bottom surface provided on the apparatus main body, and a paper feed roller provided on the apparatus main body for conveying paper in a paper feeding direction. In the image forming apparatus,
A push-up member for pressing the paper of the paper cassette against the paper feed roller is attached to the bottom surface of the chassis,
The push-up member is integrally formed with a rotating shaft portion including a shaft portion and a retaining portion for preventing the push-up member from being pulled upward.
The bottom surface of the chassis is fitted with a retaining portion and a shaft portion of the rotating shaft portion of the lifting member, and the lifting member can be rotated around the shaft portion of the rotating shaft portion. Is provided with a fitting hole to support
The fitting hole is formed to be connected to the fitting portion having a long hole shape for fitting the turning shaft portion of the push-up member, and the push-up member is connected to the turning shaft. A long hole-like support part for supporting the part pivotably about the part,
The elongated hole-like support portion of the fitting hole includes one side on which a convex portion is integrally provided and the other side on which a concave portion is integrally provided at a position corresponding to the convex portion, and the push-up The shaft portion of the member is supported by a convex portion on one side of the support portion of the fitting hole and a portion other than the concave portion on the other side,
The convex portion and the concave portion are formed in a trapezoidal shape when seen in a plan view, and the length of the convex portion in the direction perpendicular to the paper feeding direction is smaller than the length of the concave portion in the direction perpendicular to the paper feeding direction. ,
In plan view, the length of the recess in the paper feeding direction is smaller than the length of the portion of the push-up member protruding in the paper feeding direction of the retaining portion,
In plan view, the length of the fitting portion of the fitting hole of the chassis in the paper feeding direction is larger than the length of the retaining portion of the rotation shaft portion of the push-up member in the paper feeding direction,
The rotation shaft portion of the push-up member is rotatably mounted on the support portion by being moved in the horizontal direction from the fit portion to the support portion after being inserted into the fit portion. An image forming apparatus. An apparatus main body in which a paper cassette for storing paper is mounted;
A chassis having a bottom surface provided in the apparatus body;
A paper feed roller provided in the apparatus main body for conveying paper in a paper feed direction;
A push-up member attached to the bottom surface of the chassis and for pressing the paper of the paper cassette against the paper feed roller;
The push-up member is integrally formed with a rotating shaft portion including a shaft portion and a retaining portion for preventing the push-up member from being pulled upward.
The bottom surface of the chassis is fitted with a retaining portion and a shaft portion of the rotating shaft portion of the lifting member, and the lifting member can be rotated around the shaft portion of the rotating shaft portion. Is provided with a fitting hole to support
The fitting hole is formed to be connected to the fitting portion having a long hole shape for fitting the turning shaft portion of the push-up member, and the push-up member is connected to the turning shaft. A long hole-like support part for supporting the part pivotably about the part,
The long hole-shaped support portion of the fitting hole includes one side on which a convex portion is integrally provided and the other side on which a concave portion is integrally provided at a position corresponding to the convex portion, and the push-up member The shaft portion is supported by a convex portion on one side of the support portion of the fitting hole and a portion other than the concave portion on the other side.
Image forming apparatus.   The convex portion and the concave portion are formed in a trapezoidal shape when seen in a plan view, and the length of the convex portion in the direction perpendicular to the paper feeding direction is smaller than the length of the concave portion in the direction perpendicular to the paper feeding direction. The image forming apparatus according to claim 2.   4. The image formation according to claim 2, wherein a length of the concave portion in the paper feeding direction is smaller than a length of a portion of the push-up member protruding in the paper feeding direction in a plan view. apparatus.   In plan view, the length of the fitting portion of the fitting hole of the chassis in the paper feeding direction is larger than the length of the retaining portion of the rotation shaft portion of the lifting member in the paper feeding direction. The image forming apparatus according to claim 2. The rotation shaft portion of the push-up member is rotatably mounted on the support portion by being moved in the horizontal direction from the fit portion to the support portion after being inserted into the fit portion. The image forming apparatus according to any one of claims 2 to 5.

Images