Apparatus body and image forming apparatus

Abstract

To provide an apparatus main body and an image forming apparatus that can reduce an operating force during withdrawal of a drawer member.SOLUTION: An apparatus main body 35 comprises: a housing 2; a drawer member 34; a positioning mechanism 47 that performs positioning at a mounting position of the drawer member 34 with respect to the housing 2; and a push-out mechanism 41 that pushes out the drawer member 34 from the mounting position by a predetermined amount during withdrawal of the drawer member 34 from the housing 2. The positioning mechanism 47 includes fitting holes 38a, 38b that are provided in either one of the housing 2 or the drawer member 34, and positioning pins 39a, 39b that are provided in the other of them and fitted to the fitting holes 38a, 38b, and in a fitted state in which the fitting hole 38 and the positioning pin 39 are fitted to each other, performs positioning at the mounting position of the drawer member 34. The positioning pin 39 and the fitting hole 38 are formed in shapes such that when the drawer member 34 is pushed out by the push-out mechanism 41 from the mounting position by the predetermined amount, the fitted state is released.SELECTED DRAWING: Figure 5

Description

[Technical field]

[0001] The present invention relates to an apparatus main body and an image forming apparatus. [Background technology]

[0002] Conventionally, there is known a device body equipped with a drawer member that is provided so as to be freely inserted and removed. A positioning mechanism is provided between the device body and the drawer member for positioning the drawer member when it is attached, and this mechanism is usually configured by fitting a positioning pin provided on one side into a positioning hole provided on the other side. In a device equipped with such a positioning mechanism, in order to reduce the operating force required when removing the drawer member from the device main body, a technology is known in which a locking member is provided on either the device main body or the drawer member, and on the other a locked wall with which the locking member engages in the locked position, and a pushing wall that abuts against the locking member when the locking member rotates in the unlocking direction and pushes the drawer member in the removal direction as the locking member rotates (see, for example, Patent Document 1). Summary of the Invention [Problem to be solved by the invention]

[0003] In the above-mentioned technology, the push-out wall moves the drawer member in the removal direction, which is said to reduce the operating force required for removal. However, as described above, when the drawer member is attached, the device body and the drawer member are fitted to each other by the positioning mechanism, and this fitted state continues even when the drawer member is moved by the push-out wall, so the weight of the drawer member acts on the fitting portion, and there is a problem that a large operating force is still required for removal. SUMMARY OF THE PRESENT DISCLOSURE An object of the present invention is to provide an apparatus body and an image forming apparatus that can solve the above-mentioned problems and reduce the operating force required when removing and extracting a drawer member. [Means for solving the problem]

[0004] The invention described in claim 1 comprises a housing, a drawer member provided so as to be freely inserted and removed from the housing, a positioning mechanism for positioning the drawer member at an installation position relative to the housing, and a push-out mechanism for pushing the drawer member a predetermined amount from the installation position when the drawer member is removed from the housing, the positioning mechanism including a fitting hole provided in either the housing or the drawer member, and a positioning pin provided in the other and fitting into the fitting hole, the positioning mechanism for positioning the drawer member at the installation position in a fitted state in which the fitting hole and the positioning pin are fitted together, and when the drawer member is pushed out the predetermined amount from the installation position by the push-out mechanism, A gap occurs between the fitting hole and the positioning pin. It is characterized by being formed into a shape. Effect of the Invention

[0005] According to the present invention, when the push-out mechanism is activated to push out the pull-out member a predetermined amount and the pull-out member is displaced from the attached position to the released state, a gap is formed between the mating hole and the positioning pin, and the weight of the pull-out member does not act on the mating hole formed in the pull-out member that has been pushed out a predetermined amount in the removal direction from the attached position, so it is possible to provide an apparatus body and an image forming apparatus that can reduce the operating force required when removing the pull-out member. [Brief description of the drawings]

[0006] [Figure 1] 1 is a schematic diagram illustrating an image forming apparatus to which an embodiment of the present invention can be applied. [Diagram 2] FIG. 2 is a schematic diagram illustrating an apparatus main body used in one embodiment of the present invention. [Diagram 3] 3A to 3C are schematic diagrams illustrating the configuration and operation of a push-out mechanism used in one embodiment of the present invention. [Figure 4] FIG. 1 is a schematic diagram illustrating a problem in the conventional art. [Diagram 5] 4 is a schematic diagram illustrating a positioning mechanism used in one embodiment of the present invention. FIG. [Figure 6] 13A to 13C are schematic diagrams illustrating the configuration and operation of a push-out mechanism used in a modified example of one embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0007] 1 is a schematic diagram of an image forming apparatus according to an embodiment of the present invention. In the figure, the image forming apparatus 1 is a multifunction machine having a printer function and a copying function, and includes a housing 2, a document reading unit 3, an image forming unit 4, and a paper feeding unit 5. The document reading section 3 includes a document transport section 6 and a reading device 7. The document transport section 6 transports a document placed on a document tray 8 along a document transport path 9, and the transported document is discharged onto a document discharge tray 11 via a contact glass 10. The reading device 7 includes an image reader 12 that is disposed below the contact glass 10 and reads an image of the document transported over the contact glass 10 to generate image data. The generated image data is sent to the image forming section 4.

[0008] The paper feed section 5 includes a plurality of paper feed trays 13, 14, and 15 that store transfer sheets S, which are recording media, and a paper feed path 16 through which the transfer sheets S fed from each of the paper feed trays 13, 14, and 15 pass. Each of the paper feed trays 13, 14, and 15 stores transfer sheets S of different sizes, and each of the stored transfer sheets S is separated and fed one by one by a paper feed roller 17 and fed toward the image forming section 4 via the paper feed path 16. 1, a manual feed tray 18 is provided on the right side of the housing 2 so as to protrude from the side wall. The transfer sheets S placed on the manual feed tray 18 are separated and fed one by one by a paper feed roller 19 and sent to the image forming unit 4.

[0009] The image forming unit 4 forms a full-color image using four color toners: yellow (Y), magenta (M), cyan (C), and black (K). The image forming unit 4 has four color image forming units 20Y, 20M, 20C, and 20K, and an optical writing unit 21, and the image forming units 20Y, 20M, 20C, and 20K are arranged in a tandem type in a horizontal direction. Each of the image forming units 20Y, 20M, 20C, and 20K is an image carrier and includes photoconductor drums 22Y, 22M, 22C, and 22K that rotate counterclockwise in FIG. 1, and an electrostatic latent image is formed on the peripheral surface of each of the photoconductor drums 22Y, 22M, 22C, and 22K by exposure scanning from the optical writing unit 21. The electrostatic latent images of each color that are formed are developed with toner of each color contained in a developing device provided in each image forming unit 20Y, 20M, 20C, and 20K, respectively, and a toner image of each color is formed on the peripheral surface of each photosensitive drum 22Y, 22M, 22C, and 22K, respectively.

[0010] The image forming unit 4 is provided with a control unit 23 that controls the operation of each component in the image forming apparatus 1. The control unit 23 receives image data sent from the document reading unit 3, image data generated and sent by an external computer, etc. Then, based on control based on this image data, exposure scanning by the optical writing unit 21 and toner image formation operations in each of the image forming units 20Y, 20M, 20C, and 20K are performed. In addition to this, the control unit 23 controls various operations in the image forming apparatus 1.

[0011] The image forming unit 4 further includes primary transfer rollers 24Y, 24M, 24C, and 24K, an intermediate transfer belt 25, a pair of registration rollers 26, a secondary transfer roller 27, and a fixing device 28. The intermediate transfer belt 25 is driven to run in a clockwise direction in FIG. 1, and during this run, the respective color toner images formed on the respective photoconductor drums 22Y, 22M, 22C, and 22K are superimposed and transferred by the respective primary transfer rollers 24Y, 24M, 24C, and 24K, so that a full-color toner image is formed on the intermediate transfer belt 25.

[0012] Meanwhile, the transfer sheet S is fed from the paper feed unit 5 toward the image forming unit 4. The transfer sheet S fed from each of the paper feed trays 13, 14, 15 or the manual feed tray 18 is temporarily stopped by a pair of registration rollers 26 to correct any skew. The pair of registration rollers 26 then rotates at a predetermined timing to feed the transfer sheet S to a secondary transfer roller 27, which then brings the transfer sheet S into contact with the intermediate transfer belt 25, thereby secondarily transferring the full-color toner image onto the transfer sheet S. The transfer sheet S onto which the toner image has been transferred is sent via a conveyor belt 29 to a fixing device 28, where the transferred toner image is fixed by heat and pressure, after which the sheet is discharged outside the housing 2 by a pair of discharge rollers 30 and stacked on a discharge tray 31.

[0013] The image forming apparatus 1 is configured to be capable of forming an image on one side or both sides of the transfer sheet S. Whether to perform single-sided image formation or double-sided image formation is set based on a user's setting operation or setting information from an external device. When single-sided image formation is set, image formation is performed by the series of operations described above. On the other hand, when double-sided image formation is set, the transfer sheet S, which has passed through the fixing device 28 after a toner image has been formed on one side, is sent to a reverse conveying path 32. The transfer sheet S which has passed through the reverse conveying path 32 is fed to a secondary transfer roller 27 by the operation of a pair of registration rollers 26 in a manner that the back side on which the toner image is not formed faces the intermediate transfer belt 25. Then, after the toner image is transferred and fixed to the back side, the transfer sheet S is discharged onto a paper discharge tray 31 by a pair of discharge rollers 30.

[0014] In the image forming apparatus 1, a plurality of paper detection sensors for detecting the presence of the transfer sheet S are provided inside the housing 2. In this embodiment, a paper detection sensor 33a is provided on the downstream side of the paper feed roller 19 provided on the manual feed tray 18 in the sheet conveying direction, a paper detection sensor 33b is provided on the downstream side of the junction where the sheets fed from the paper feed trays 13, 14, and 15 join, and a paper detection sensor 33c is provided on the upstream side of the registration roller pair 26 in the sheet conveying direction. In addition, a paper detection sensor 33d is provided above the conveyor belt 29, a paper detection sensor 33e is provided on the upstream side of the fixing device 28 in the sheet conveying direction, a paper detection sensor 33f is provided on the downstream side of the fixing device 28 in the sheet conveying direction, and a paper detection sensor 33g is provided on the upstream side of the discharge roller pair 30 in the sheet conveying direction. The detection results by each paper detection sensor 33 are sent to the control unit 23 and are used to identify the location of the jam when a jam of the transfer sheet S occurs inside the housing 2.

[0015] The housing 2 is also provided with a drawer member 34 that is configured to be freely inserted into and removed from the housing 2. The drawer member 34 supports the registration roller pair 26, the secondary transfer roller 27, the fixing device 28, the discharge roller pair 30, the reverse transport path 32, etc., and these members are configured to be removable from the housing 2 as a unit by pulling the drawer member 34 out of the housing 2. The housing 2 and the drawer member 34 form an apparatus main body 35.

[0016] 2, the drawer member 34 is moved (inserted) in an insertion direction A from the front side where the user is positioned toward the back side to be attached to the housing 2, and is moved (removed) in a removal direction B opposite to the insertion direction A to be removed from the housing 2. The conveying direction C of the transfer sheet S in the drawer member 34 is perpendicular to the insertion direction A and the removal direction B. The drawer member 34 has a member body 36 that holds each component such as the fixing device 28 described above, and a front side plate 37 attached to the front side of the member body 36. The front side plate 37 is formed with a main fitting hole 38a and a secondary fitting hole 38b for positioning the drawer member 34 with the housing 2 when the drawer member 34 is in the mounting position mounted on the housing 2. The fitting holes 38a, 38b are fitted with positioning pins 39a, 39b provided on the housing 2, respectively.

[0017] The main fitting hole 38a is formed to be circular, and the secondary fitting hole 38b is formed to be oval, and they are arranged in parallel in the same direction as the transport direction C of the transfer sheet S, near both ends of the housing 2. The secondary fitting hole 38b has the same dimension of its short diameter as the main fitting hole 38a, and its long diameter is larger than that of the main fitting hole 38a and is formed long in the same direction as the transport direction C of the transfer sheet S. This configuration of the fitting holes 38a, 38b makes it possible to suppress inclination of the pull-out member 34 in the transport direction C of the transfer sheet S. The positioning pins 39a, 39b are disposed near both ends of the front side of the housing 2 so as to be able to fit into the fitting holes 38a, 38b. The positioning pins 39a, 39b are formed with a pointed tip so as to be easily fitted into the fitting holes 38a, 38b. The shapes of the fitting holes 38a, 38b and the positioning pins 39a, 39b will be described later.

[0018] The member body 36 is supported by a pair of rail members 40 provided on the housing 2 so as to be movable in an insertion direction A and a removal direction B. The member body 36 is also provided with a control unit, cables, etc. (not shown) that enable electrical connection with the control unit 23 and a power supply device provided on the housing 2, and the operations of each member mounted on the member body 36 are controlled by the power supply and control unit 23 from the housing 2 side. In the above-described configuration, the fitting holes 38a, 38b are provided on the drawer member 34 side and the positioning pins 39a, 39b are provided on the housing 2 side. However, it is also possible to provide the positioning pins 39a, 39b on the drawer member 34 side and the fitting holes 38a, 38b on the housing 2 side.

[0019] 3, a push-out mechanism 41 is provided near a rear side plate 2b that is provided opposite to a front side plate 2a of the housing 2. The push-out mechanism 41 holds the pull-out member 34 in the attached position relative to the housing 2, and pushes the pull-out member 34 out of the attached position by a predetermined amount to assist in removing the pull-out member 34 from the housing 2. The push-out mechanism 41 has a compression spring 42 as a biasing member, and a holding mechanism 43 that holds the pull-out member 34 in the attached position. The compression spring 42 has one end in contact with the rear side plate 2b and the other end in contact with the member body 36, and biases the member body 36 in the removal direction B.

[0020] The holding mechanism 43 has a hook-shaped engaged portion 36a formed integrally with the member body 36, and a holding member 44 that can engage with the engaged portion 36a. The holding member 44 is supported at its center by a support shaft 44a on a side plate (not shown) of the housing 2 so as to be rotatable, and a hook-shaped engaging portion 44b that can engage with the engaged portion 36a is formed on one end side. The other end 44c of the holding member 44 extends to the outside of the housing 2 from an opening 2c formed in the rear side plate 2b, and is configured to be manually pushed down. The support shaft 44a is provided with a torsion coil spring (not shown), and the holding member 44 is biased to maintain the state shown in FIG. 3(a).

[0021] 3(a) shows a state in which the drawer member 34 is in the attached position, and in this state, the holding member 44 is in an engaged position in which the engaging portion 44b is engaged with the engaged portion 36a. When the other end portion 44c is manually pushed downward from this state, the holding member 44 is displaced to a disengaged position in which the engaging portion 44b and the engaged portion 36a are disengaged, and the member body 36 is pushed in the removal direction B by the compression spring 42, resulting in a release state in which the member body 36 is pushed out a predetermined amount from the attached position as shown in FIG. 3(b).

[0022] Next, the shapes of the fitting holes 38a, 38b and the positioning pins 39a, 39b will be described. Prior to describing the configuration of the present invention, first, the shapes of the fitting holes and positioning pins that have been conventionally used and the problems associated with them will be described. 4 shows a conventionally used fitting hole 50 and a positioning pin 51 that fits into the fitting hole 50. The fitting holes 50 are disposed near both end portions of a front plate 52 of a drawer member (not shown), one of which is formed in a circular shape and the other in an elliptical shape. The positioning pins 51 are disposed in the vicinity of both side ends of a housing (not shown) at positions corresponding to the fitting holes 50, respectively.

[0023] When a drawer member (not shown) is inserted into a housing (not shown) and takes the attached position, each fitting hole 50 and each positioning pin 51 are fitted into each other as shown in Fig. 4(a). In this state, the straight portions of each positioning pin 51 are securely fitted into each fitting hole 50, and the drawer member (not shown) is securely positioned relative to the housing (not shown). Thereafter, when a push-out mechanism (not shown) similar to that of this embodiment is operated, the drawer member (not shown) is pushed out a predetermined amount, and the front side plate 52 moves leftward relative to the positioning pin 51, as shown in FIG. 4(b). However, even in this state, in the conventional technology, the straight portions of the positioning pins 51 are firmly fitted into the fitting holes 50, and when the drawer member that has been moved a predetermined amount in the removal direction B is pulled out, a frictional force proportional to the weight of the drawer member (not shown) acts between the fitting holes 50 and the straight portions of the positioning pins 51. In the conventional configuration, in order to further pull out the drawer member (not shown) from this state, a large force is required as the removal operation force to compensate for the frictional force acting.

[0024] The configuration of one embodiment of the present invention that solves the above-mentioned problems will be described below. In Fig. 5, which shows one embodiment of the present invention, the fitting holes 38a, 38b and the positioning pins 39a, 39b form a positioning mechanism 47. The positioning pins 39a, 39b used in this embodiment are configured so that the tapered portion formed at the tip is longer than that of a conventional positioning pin 50. When the drawer member 34 is inserted into the housing 2 and takes the attached position, the fitting holes 38a, 38b and the positioning pins 39a, 39b take the position shown in Fig. 5(a) in which they fit together. In this state, the straight portions 39c (only the positioning pin 39a side is shown) of the positioning pins 39a, 39b are firmly fitted into the fitting holes 38a, 38b, and the positioning mechanism 47 firmly positions the drawer member 34 relative to the housing 2.

[0025] Thereafter, when the pushing mechanism 41 is operated, the pull-out member 34 is pushed out a predetermined amount, and the front side plate 37 moves leftward relative to the positioning pins 39a, 39b (only the positioning pin 39a side is shown), as shown in FIG. 5(b). In this state, the straight portions 39c of the positioning pins 39a, 39b are disengaged from the fitting holes 38a, 38b, and the tapered portions 39d (only the positioning pin 39a side is shown) formed at the tip portions of the positioning pins are positioned in the fitting holes 38a, 38b. As a result, when the pull-out member that has been moved a predetermined amount in the removal direction B is pulled out, a gap D is generated between the fitting holes 38a, 38b and the tapered portions 39d of the positioning pins 39a, 39b because the tapered portions 39d are longer than in the conventional configuration.

[0026] According to the present invention, with the above-mentioned configuration, when the push-out mechanism 41 is actuated to push out the drawer member 34 by a predetermined amount and the drawer member 34 is displaced from the attached position to the released state, the positioning pins 39a, 39b that have been fitted into the fitting holes 38a, 38b are displaced relative to the fitting holes 38a, 38b. As a result, the positioning pins 39a, 39b that have been fitted with the straight portions 39c into the fitting holes 38a, 38b position the tapered portions 39d with respect to the fitting holes 38a, 38b. Since a gap D is formed between the fitting holes 38a, 38b and the tapered portions 39d, the weight of the drawer member 34 does not act on the fitting holes 38a, 38b formed in the drawer member 34 that has been pushed out by a predetermined amount in the removal direction B from the attached position. This makes it possible to provide the device body 35 that can reduce the operating force required when removing the drawer member 34.

[0027] Next, a modification of the above-mentioned embodiment will be described with reference to FIG. The modified example shown in FIG. 6 differs from the embodiment shown in FIG. 3 in that a solenoid 45 is used as a drive unit for driving a holding member 44, but the other configurations are the same. The solenoid 45 is fixed to the outside of the rear side plate 2b by a bracket 46, and the tip of the plunger 45a is attached to the other end 44c of the holding member 44. The operation of the solenoid 45 is controlled by the control unit 23, and when the plunger 45a occupies the first position shown in Fig. 6(a), the holding member 44 occupies the engaged position, and when the plunger 45a occupies the second position shown in Fig. 6(b), the holding member 44 occupies the disengaged position. According to this configuration, the operation of the holding member 44 can be performed automatically, and the operation of pulling out the pull-out member 34 from the housing 2 can be simplified.

[0028] In the above embodiment and each modified example, an example was shown in which the image forming apparatus 1, which is a multifunction machine capable of forming a full-color image and has a printer function and a copying function, is used as the image forming apparatus, but the image forming apparatus is not limited to this, and the present invention is also applicable to printers, facsimiles, copying machines, etc. Also, in this embodiment, a configuration was shown in which a transfer sheet S is used as a recording medium on which an image is formed, but this transfer sheet S is not limited to recording paper, and also includes cardboard, postcards, envelopes, plain paper, thin paper, coated paper (coated paper, art paper, etc.), tracing paper, OHP sheets, OHP films, resin films, etc., and any material that is sheet-shaped and capable of forming an image may be used.

[0029] Although the preferred embodiments of the present invention have been described above, the present invention is not limited to such specific embodiments, and various modifications and changes are possible within the scope of the spirit of the present invention described in the claims unless otherwise specifically limited in the above description. The effects described in the embodiments of the present invention are merely examples of the most preferable effects resulting from the present invention, and the effects of the present invention are not limited to those described in the embodiments of the present invention. [Explanation of symbols]

[0030] 1. Image forming device 2. Chassis 23 Control Unit 34 Drawer member 35 Device body 38a Main fitting hole 38b Compliant fitting hole 39a, 39b Locating pin 41 Push-out mechanism 42 Pressurizing member (compression spring) 43 Retention mechanism 44 Retaining member 45 Drive unit (solenoid) 47 Positioning mechanism [Prior art documents] [Patent documents]

[0031] [Patent Document 1] JP 2001-253620 A

Claims

1. A housing and A drawer member that is provided so as to be freely inserted and removed from the housing; a positioning mechanism for positioning the drawer member at a mounting position relative to the housing; a push-out mechanism that pushes out the pull-out member a predetermined amount from the mounting position when the pull-out member is removed from the housing; the positioning mechanism includes a fitting hole provided in either the housing or the drawer member, and a positioning pin provided in the other of the housing and fitted into the fitting hole, and positions the drawer member at the mounting position in a fitted state in which the fitting hole and the positioning pin are fitted into each other; The positioning pin and the fitting hole are formed in a shape such that a gap is generated between the fitting hole and the positioning pin when the pull-out member is pushed out the predetermined amount from the mounting position by the push-out mechanism.

2. The device body according to claim 1, The device body, wherein the pushing-out mechanism has a biasing member that biases the pull-out member in a pushing direction, and a holding mechanism that holds the pull-out member in the mounting position.

3. The device body according to claim 2, The device body is characterized in that the holding mechanism has a holding member that can be engaged with and detached from the drawer member.

4. In the device body according to claim 3, The device body, characterized in that the holding member is manually operated.

5. In the device body according to claim 3, The holding member is automatically operated, and the device body has a drive unit that drives the holding member, and a control unit that controls the operation of the drive unit.

6. 6. An image forming apparatus comprising the main body according to claim 1.

Images