JP5413009B2 - Pull-in device and image forming apparatus - Google Patents

Description

  The present invention relates to a pull-in device and an image forming apparatus, and more particularly to a pull-in device including a pull-in unit that pulls a paper feed cassette into a main body device and an image forming apparatus including the pull-in device.

  In general, an image forming apparatus includes a reading unit that reads an image of a document placed on a contact glass, an image forming unit that forms an image read by the reading unit on recording paper, and supplies the recording paper to the image forming unit. An electrostatic latent image is formed by irradiating the surface of the photosensitive member with light by an optical writing device included in the image forming unit, and cyan on the electrostatic latent image formed on the surface of the photosensitive member. In addition, toner composed of magenta, yellow, and black color components is supplied to form a visible image as a toner image, and a color image is formed by transferring the toner image of each color component onto a transfer material.

  Further, the above-described image forming apparatus has a paper feed cassette that stores recording paper. This paper feed cassette is configured to be detachable in the pull-out direction with respect to the paper feed unit via a pair of left and right rail members provided inside the paper feed unit so that recording paper can be replenished appropriately. It has become.

  Such a drawer-type paper feed cassette is heavy in a state where recording paper is replenished, and therefore places a heavy burden on the user when the paper feed cassette is attached or detached. In addition, since the paper feed cassette is heavy, if the user is given an excessive operating force, the paper feed cassette may be installed in the paper feed unit vigorously. In such a case, it is conceivable that the position of the recording paper stored in the paper feed cassette is shifted or the paper feed cassette is damaged due to an impact when the paper feed cassette is mounted.

  Conventionally, in this type of image forming apparatus, when a locking pin provided in a sheet feeding cassette and a locking pin are locked and swinged to a predetermined swinging position, a toggle spring is interposed through the locking pin. A pull-in device that pulls the paper cassette toward the main body, and a guide groove for a locking pin that includes a linear portion parallel to the mounting direction of the paper cassette and a curved portion curved toward the swing fulcrum of the pull-in device. The thing provided with the guide is known (for example, refer patent document 1).

  As a result, in the image forming apparatus described in Patent Document 1 described above, the paper feeding cassette is guided to the guide via the locking pin, and the pulling device locks the locking pin to the predetermined swinging position. When moved, the paper feeding cassette is pulled in by using the urging force of the toggle spring, so that the burden on the user can be reduced. Further, since the guide described above has a curved portion curved in the direction of the swing fulcrum of the retracting device, when the locking pin is guided to the curved portion, the retracting device swings due to the biasing force of the toggle spring. As a result, the paper feeding cassette can be reliably pulled in without increasing the spring constant of the toggle spring.

  Also known is a device having a speed-dependent damper unit that increases or decreases a load for decelerating the moving speed of the paper feeding cassette according to the magnitude of the moving speed of the paper feeding cassette drawn by the biasing force of the toggle spring. (For example, refer to Patent Document 2).

  As a result, the image forming apparatus described in Patent Document 2 described above decelerates the movement speed of the paper feed cassette by the speed-dependent damper unit according to the magnitude of the movement speed of the paper feed cassette. Regardless of the increase or decrease in the storage capacity of the recording paper, variation in the moving speed of the paper feeding cassette can be suppressed. For this reason, it is possible to prevent the recording sheets stacked and accommodated in the paper feed cassette from collapsing due to an impact when the paper feed cassette is mounted, and to prevent the paper feed cassette from being damaged.

  However, in the above-described conventional image forming apparatus, the sliding resistance between the rail member provided in the main body device and the paper feed cassette is not considered. Therefore, if the sliding resistance between the rail member and the paper feed cassette is large, the paper feed cassette needs to be pulled in with a pulling force larger than this sliding resistance, so the spring constant of the toggle spring is increased. It was necessary to increase the biasing force of the toggle spring.

  Further, in the pulling device, the pulling force required to pull in the paper feed cassette is stored by the toggle spring being displaced when the paper feed cassette is pulled out. For this reason, when the sliding resistance between the rail member and the paper feed cassette is large, if the spring constant of the toggle spring is increased, the force required to store the pulling force increases.

  Therefore, when the sliding resistance between the rail member and the paper cassette is large, the force necessary to store the pull-in force increases, so that the force required to pull out the paper cassette increases, There was a problem that the operability of the paper cassette was impaired.

  In addition, the conventional image forming apparatus described above does not include means for restricting the movement of the paper feed cassette in a direction perpendicular to the paper feed cassette attachment / detachment direction. The amount of movement of the sheet feeding cassette in the direction perpendicular to the attaching / detaching direction may increase. In this case, when the locking pin provided in the sheet feeding cassette and the guide are engaged, the positional relationship between the locking pin and the guide is deviated from a predetermined appropriate positional relationship.

  For this reason, since the collision load at the time of contact between the locking pin and the guide increases, the force required for mounting the paper feed cassette increases. Therefore, there is a problem that the operability of the paper feed cassette is impaired.

  SUMMARY An advantage of some aspects of the invention is that it provides a pull-in device and an image forming apparatus that can improve the operability of a paper feed cassette.

In order to achieve the above object, an image forming apparatus according to the present invention has a guide rail fixed to a main body device, a slide rail that can slide relative to the guide rail, and a relative position relative to the slide rail. A slidable paper feed cassette, a unit that can be pulled out and retracted with respect to the main body device, an engagement member provided in one of the main body device and the paper feed cassette, the main body device, and An engagement member provided on either one of the sheet feeding cassettes and engageable with the engagement member; the engagement member and the engagement member; and pulling the unit into the engagement wherein the member when the engaged member is engaged, the retractor unit of the unit is fixed to the main device to draw up to pull completion position of the main device, before The unit is rotatably attached to either the guide rail or the slide rail on the pull-in end of the unit, and the other on the guide rail or the slide rail on the pull-out side of the unit. The rotating body is provided on the opposite side of each rotating body of the guide rail and the slide rail, engages with each rotating body to guide the unit in the pulling-out direction and the drawing-in direction, and A guide member that regulates movement of the rotating body in a thrust direction, and the engagement member and the engaged member are either a cylindrical member or the engagement member or the engaged member. And a guide groove extending along the slide direction of the paper feed cassette on the other of the engaging member and the engaged member. Is formed, when the guide member guides the unit engaged with the rotary member, the guide groove guiding the direction perpendicular to the direction and the said unit by said cylindrical member is guided along the The movement of the sheet feeding cassette in the thrust direction of the rotating body is restricted.

  With this configuration, since the guide member engages with the rotating body and guides the unit in the pulling-out direction and the pulling-in direction, the unit can be moved in the direction perpendicular to the pulling-out direction and the pulling-in direction of the unit and in the thrust direction of the rotating body. In addition to being able to regulate, the sliding resistance of the unit relative to the main unit can be reduced as compared with the conventional case by rotating the rotating body when the unit is pulled out and retracted. Moreover, the posture of the unit can be stabilized by restricting the movement of the unit in the thrust direction of the rotating body. For this reason, when the engaging member and the engaged member are engaged when the unit is retracted, the positional relationship between the engaging member and the engaged member can be maintained within a certain range. The collision load due to contact with the engaged member can be reduced. Therefore, the sliding resistance of the unit with respect to the main unit can be reduced, and the collision load caused by the contact between the engaging member and the engaged member can be reduced, so that the operating force required for operating the retracting device can be reduced. The operability of the unit can be improved.

Further, in the retracting device according to the present invention, when the rotating body is attached to the end of the unit on the retracting side of the unit and the end of the main unit on the pulling side of the unit, Compared with the case where a rotating body is attached to either the pull-in end or the unit pull-out end of the main unit, the horizontal rotation of the unit when the unit is pulled out and pulled in is more It can be strongly regulated. Therefore, the posture of the unit is stabilized and the engaging member is engaged with the engaged member as compared with the case where a rotating body is provided at either the end of the unit on the drawing side of the unit or the end of the main unit on the drawing side of the unit. Since the collision load with the combined member can be further reduced and the operating force of the retracting device can be reduced, the operability of the unit can be further improved.

Further, the pull-in device according to the present invention is such that when the rotating body is attached to the pull-in end of the unit in the main unit and the pull-out end of the unit in the unit, the unit in the main unit Compared to the case where a rotating body is attached to either the end of the unit on the pull-in side or the end of the unit on the unit-drawing side, the horizontal rotation of the unit when the unit is pulled out or pulled in is more It can be strongly regulated. Therefore, the posture of the unit is stabilized and the engagement member is engaged with the engaged member as compared with the case where the rotating body is provided at either the end of the main unit at the drawing side of the unit or the end of the unit at the drawing side of the unit. Since the collision load with the combined member can be further reduced and the operating force of the retracting device can be reduced, the operability of the unit can be further improved.

  Further, in the retracting device according to the present invention, the rotating body has a groove portion formed in a circumferential direction on a circumferential surface of the rotating body, and the guide member includes a fitting portion that fits the groove portion. It is characterized by having.

  With this configuration, the groove portion formed in the circumferential direction on the circumferential surface of the rotating body and the fitting portion of the guide member are fitted to reduce the sliding resistance of the unit with respect to the main body device, and the drawing direction of the unit The movement of the unit in the direction perpendicular to the pull-in direction and the thrust direction of the rotating body can be restricted. Therefore, not only reducing the sliding resistance of the unit with respect to the main unit, but also when it is intended to regulate the movement of the unit in the thrust direction of the rotating body, there is no need to newly provide a member for the regulation. The retractor can be manufactured at a low cost.

  Further, in the pulling-in device according to the present invention, any one of the engaging member and the engaged member is constituted by a cylindrical member, and the groove portions are formed in a circumferential direction so as to face each other. The cylindrical member and the groove so that r / 2> A is satisfied, where r is a diameter of the cylindrical member, and A is a gap between the fitting surface and the fitting portion. And the fitting portion are formed.

  With this configuration, even if the unit moves by an amount corresponding to the gap A in the direction perpendicular to the unit drawing-out direction and the drawing-in direction and in the thrust direction of the rotating body, the position of the center of the columnar member is changed to the engagement member. And any one of the engaged members can be maintained between opposing surfaces formed to engage the cylindrical member. For this reason, compared with the case where the radius (r / 2) of a cylindrical member is smaller than the gap | interval A, and the center position of a cylindrical member cannot be maintained between the said opposing surfaces, it is engaged with an engaging member. Since the collision load at the time of engaging with the member can be reduced, the operating force of the retracting device can be reduced, and the operability of the unit can be further improved.

  Further, in the retracting device according to the present invention, the main body device and the unit each have a restricting member that restricts drawing and retracting of the unit by a predetermined pulling width, and the guide member is provided by the restricting member. It is characterized in that it is provided inside the main body device so as to engage with the rotating body in the entire range of the limited drawer width.

  With this configuration, the sliding resistance between the unit and the main unit can be reduced over the entire width of the unit. In addition, the movement of the unit in the direction perpendicular to the drawing direction and the drawing direction of the unit and in the thrust direction of the rotating body can be regulated over the entire drawing width of the unit, so that the posture of the unit can be stabilized. It is possible to reduce a collision load when the engaging member and the engaged member are engaged when retracted. Therefore, the sliding resistance between the unit and the main unit can be reduced over the entire width of the unit, and the collision load when the engaging member and the engaged member are engaged when the unit is retracted can be reduced. Therefore, the operating force of the retracting device can be reduced over the entire width of the unit, and the operability of the unit can be further improved.

  Further, the retracting device according to the present invention is characterized in that the rotating body is made of resin and the fitting portion is made of sheet metal.

  With this configuration, the size of the fitting portion can be reduced as compared with the case where the fitting portion is formed of resin. In other words, when the fitting part is made of resin, it is necessary to increase the dimension of the fitting part in order to ensure the strength to withstand the load applied when the unit is pulled out and pulled in, whereas In the case where the joint portion is formed of sheet metal, it is possible to ensure the strength to withstand the load applied when the unit is pulled out and pulled in with a size smaller than that of the resin. Therefore, since the space required for arrangement | positioning of a fitting part can be reduced rather than the case where the fitting part is formed with resin, a drawing-in apparatus can be comprised compactly.

  Furthermore, an image forming apparatus according to the present invention includes the above-described pull-in device.

  With this configuration, it is possible to improve the operability when the unit is pulled out and when the unit is pulled in the image forming apparatus, and it is possible to improve the appliance property of the image forming apparatus.

  According to the present invention, the sliding resistance between the paper feed cassette and the main body apparatus is reduced, and the paper feed cassette is restricted from moving in the direction perpendicular to the pull-out direction and the pull-in direction of the paper feed cassette. It is possible to provide a pull-in device and an image forming apparatus that can improve the operability.

1 is a configuration diagram of a printer according to an embodiment of the present invention. FIG. FIG. 3 is a configuration diagram of a yellow image forming unit of the printer according to the embodiment of the present invention. It is a block diagram of the vicinity of a frame in a state in which a side frame is opened from the printer according to the embodiment of the present invention. It is a figure which shows the state by which the guide rail was removed from the drawing-in apparatus which concerns on embodiment of this invention. (A) is a perspective view, (b) is a front view, and (c) is a side view. It is a figure which shows the state by which the guide rail was attached to the drawing-in apparatus which concerns on embodiment of this invention. (A) is a perspective view, (b) is a front view, and (c) is a side view. It is a fragmentary sectional view of the drawing-in device concerning an embodiment of the invention. (A) is sectional drawing which shows the XX 'cross section in FIG.4 (c). (B) is sectional drawing which shows the YY 'cross section in FIG.4 (c). It is a schematic diagram which shows the drawing-in unit in the drawing-in apparatus which concerns on embodiment of this invention. (A) is a side view, (b) is a bottom view. It is a perspective view of the bottom face direction showing the internal structure of the drawing unit concerning an embodiment of the invention. It is a perspective view showing the nail | claw of the drawing-in unit which concerns on embodiment of this invention. It is a bottom view showing the internal structure of the drawing unit concerning an embodiment of the invention. FIG. 6 is a plan view showing an initial state of drawing in the paper feed cassette by the drawing unit according to the embodiment of the present invention. It is a top view showing the state of balance of the energizing force of the 1st spring and the energizing force of the 2nd spring of the drawing-in unit concerning an embodiment of the invention. It is a top view showing the state where drawing-in of a paper feed cassette by a drawing-in unit concerning an embodiment of the invention was completed. It is a fragmentary top view for demonstrating the positional relationship of the engagement protrusion and guide plate of the drawing-in unit which concerns on embodiment of this invention.

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

  First, the configuration will be described. Hereinafter, an example in which the image forming apparatus of the present invention is applied to a tandem type color laser printer (hereinafter simply referred to as “printer”) in which a plurality of photoconductors are arranged in parallel will be described.

  As illustrated in FIG. 1, the printer 500 includes an image forming unit 200 and a paper feeding unit 300 that supplies the transfer paper S to the image forming unit 200. The image forming unit 200 includes four image forming units 1 (Y, M, C, and Bk) that respectively form yellow (Y), cyan (C), magenta (M), and black (Bk) images. ing. Each of the image forming units 1 (Y, M, C, Bk) includes a drum-shaped photoconductor 2 (Y, M, C, Bk), and the four photoconductors 2 (Y, M, C, Bk) are images. The forming unit 200 is arranged in parallel at a regular interval in the left-right direction in the drawing. Each photoconductor 2 (Y, M, C, Bk) is rotated in the direction of the arrow (clockwise) when driving is transmitted from a driving source (not shown) during operation of the printer 500. In addition, each image forming unit 1 (Y, M, C, Bk) includes a developing device or the like necessary for image formation of an electrophotographic system provided around each photoconductor 2 (Y, M, C, Bk). A member is provided. In the present embodiment, Y (yellow), C (cyan), M (representing the color) are displayed after the number indicating the constituent member of each image forming unit 1 for convenience so as to correspond to the toner color of the image to be formed. Magenta) and Bk (black). In the general description, these subscripts may be omitted. Each image forming unit 1 (Y, M, C, Bk) is configured similarly except that the color of the toner used is different. Hereinafter, details of the image forming unit 1Y for yellow will be described.

  As shown in FIG. 2, in the yellow image forming unit 1Y, a charging device 4Y, a developing device 5Y, and a cleaning device are formed as image forming members around the photoreceptor 2Y in the clockwise direction in the order of the electrophotographic process. The device 3Y is arranged in order. The charging device 4Y charges the photoreceptor 2Y according to the image to be formed, and includes a charging roller 4aY that faces the photoreceptor 2Y. The developing device 5Y applies toner to the charged photoreceptor 2Y, and includes a developing roller 5aY, a developing blade 5bY, and a screw 5cY. The cleaning device 3Y removes toner from the photoreceptor 2Y, and includes a cleaning brush 3aY, a cleaning blade 3bY, and a recovery screw 3cY.

  The photoreceptor 2Y has a layer structure in which, for example, aluminum is formed in a cylindrical shape with a diameter of about 30 to 120 [mm], and an organic semiconductor layer that is a photoconductive substance is provided on the surface. Note that the photoconductor 2Y is not limited to a cylindrical shape, and may be, for example, a belt shape.

  As shown in FIG. 1, below the photosensitive member 2 (Y, C, M, Bk), the surface of each photosensitive member 2 uniformly charged by each charging device 4 corresponds to image data for each color. An exposure device 80 is provided as latent image forming means for scanning the laser beam 8 and forming an electrostatic latent image. Between each charging device 4 and each developing device 5, an elongated space is secured in the direction of the rotation axis of the photoconductor 2 so that the laser light 8 irradiated by the exposure device 80 enters the photoconductor 2. ing.

  The exposure apparatus 80 shown in FIG. 1 has a laser scan type configuration including a semiconductor laser light source (not shown), a polygon mirror, etc., and modulates from four semiconductor laser light sources (not shown) according to image data to be formed. The emitted laser beam 8 (Y, C, M, Bk) is emitted. The exposure apparatus 80 has a configuration in which an optical component and a control component are housed in a metal or resin casing, and a light-transmitting dustproof member is provided at the upper exit. Although the printer 500 shown in FIG. 1 includes one exposure device 80, a plurality of exposure devices may be individually provided in each image forming unit. Further, as the exposure apparatus 80, a combination of a known LED (Light Emitting Diode) array and an imaging means (for example, a converging lens) may be used in addition to a semiconductor laser light source. . In this case, several thousand to several tens of thousands of finely processed LEDs are arranged on a straight line, and photosensitive writing is performed with the LEDs corresponding to the dots of the latent image on the photosensitive member 2, so that the optical system is only a simple converging lens. As a result, a mechanical drive system such as a polygon mirror is not required, and reliability can be improved, cost can be reduced, and miniaturization can be realized.

  When the yellow (Y), cyan (C), magenta (M), and black (Bk) toners are consumed by the developing devices 5 (Y, C, M, and Bk) that handle the respective colors, toner detection means (not shown) Is to be detected. Each color toner is supplied to each developing device 5 from four toner cartridges 40 (Y, C, M, Bk) containing toner of each color provided in the upper part of the printer 500 by toner replenishing means (not shown). It has become so. The outer shell of each toner cartridge 40 is configured as a container made of resin, paper, or the like. A part of the outer shell is provided with a discharge port (not shown) so that it can be easily attached to and detached from the mounting portion 400 of the printer 500. When the toner cartridge 40 is mounted on the mounting portion 400, the discharge port of the toner cartridge 40 is coupled to the toner replenishing means provided in the printer 500 main body. In addition, in the printer 500, the mounting unit 400 and the toner cartridge 40 are paired so that the toner cartridge 40 of each color is erroneously mounted and toner is not replenished to a developing device that handles different colors. Wear prevention means are provided.

  As shown in FIG. 2, the developing device 5 includes two screws 5c for stirring and transporting the toner and the carrier. When the developing device 5 is attached to the printer 500, one end of the toner replenishing means is connected to the upper part of the left screw 5c in FIG. The toner is supplied to the developing roller 5a rotating in the direction of the arrow (counterclockwise) by the screw 5c, but the toner blade on the surface of the developing roller 5a is regulated to have a predetermined thickness by the developing blade 5b. It is like that. The developing roller 5a is made of stainless steel or aluminum formed in a cylindrical shape, and is rotatably supported by a frame (not shown) of the developing device 5 so that the distance from the photosensitive member 2 is properly secured. Is provided with a magnet so as to form a predetermined magnetic field line. The electrostatic latent image for each color formed on the surface of each photoconductor 2 by the laser light 8 is developed by the developing device 5 that handles toner of a predetermined color to become a visible image.

  As shown in FIG. 1, an intermediate transfer unit 6 is provided on the upper portion of the photoreceptor 2 (Y, C, M, Bk). The intermediate transfer unit 6 includes an intermediate transfer belt 6a as an image carrier that is supported and stretched by a secondary transfer counter roller 6b, rollers 6c and 6d, and a cleaning counter roller 6e. The intermediate transfer belt 6a travels in an arrow direction (counterclockwise) by rotation of a roller 6b to which driving is transmitted from a driving source (not shown). The intermediate transfer belt 6a is composed of an endless belt, and is stretched and arranged so that the surfaces of the respective photoreceptors 2 after contacting the developing device 5 are in contact with each other. Four primary transfer rollers 7 (Y, C, M, K) are provided on the inner peripheral portion of the intermediate transfer belt 6 a so as to face the respective photoreceptors 2.

  A belt cleaning device 6h is provided on the outer peripheral portion of the intermediate transfer belt 6a at a position facing the cleaning counter roller 6e. The belt cleaning device 6h wipes off unnecessary toner remaining on the surface of the intermediate transfer belt 6a and foreign matters such as paper dust. The cleaning counter roller 6e facing the belt cleaning device 6h includes a mechanism for applying tension to the intermediate transfer belt 6a, and is configured to be movable so as to always apply appropriate belt tension to the intermediate transfer belt 6a. The belt cleaning device 6h is also moved in conjunction with the cleaning counter roller 6e.

The intermediate transfer belt 6a is, for example, a belt based on a resin film or rubber having a thickness of 50 to 600 [μm], and applies a toner image carried by each photoreceptor 2 to each primary transfer roller 7. It has a resistance value that can be electrostatically transferred to the surface of the intermediate transfer belt 6a by a bias. Each member related to the intermediate transfer belt 6a is integrally supported with the intermediate transfer belt 6a and is configured as an intermediate transfer unit 6, and can be attached to and detached from the printer 500. The intermediate transfer belt 6a is made of, for example, a material in which carbon is dispersed in polyamide, and a volume resistance value of which is adjusted to about 10 ⁶ to 10 ¹² [Ωcm]. Further, the intermediate transfer belt 6a is provided with a belt detent rib (not shown) for stabilizing traveling at at least one end portion in the width direction of the intermediate transfer belt 6a.

The primary transfer roller 7 is composed of, for example, a surface of a metal roller as a core metal covered with a conductive rubber material, and a bias is applied to the metal roller from a power source (not shown). . The conductive rubber material is made of, for example, a material in which carbon is dispersed in urethane rubber and the volume resistance is adjusted to about 10 ⁵ [Ωcm]. The primary transfer roller 7 may be a metal roller that does not have a conductive rubber material layer on the surface.

A secondary transfer roller 14a is provided at a position on the outer periphery of the intermediate transfer belt 6a and opposed to a secondary transfer counter roller 6b as a support roller across the intermediate transfer belt 6a. The secondary transfer roller 14a is constituted by a surface of a metal roller as a core metal covered with a conductive rubber material, and a bias is applied to the metal roller from a power source 14b. Carbon is dispersed in the conductive rubber material, and the volume resistance of the conductive rubber material is adjusted to about 10 ⁷ [Ωcm]. The secondary transfer roller 14a abuts on the intermediate transfer belt 6a at a position facing the secondary transfer counter roller 6b to form a secondary transfer nip as a secondary transfer portion. At the secondary transfer nip, that is, at the contact portion between the secondary transfer roller 14a and the intermediate transfer belt 6a, a transfer sheet S as a recording sheet is passed between the intermediate transfer belt 6a and the secondary transfer roller 14a. By applying a bias, the toner image carried by the intermediate transfer belt 6a is electrostatically transferred onto the transfer paper S.

  A plurality of stages (for example, two stages) of paper feed cassettes 9A and 9B are provided in the paper feed unit 300 below the exposure apparatus 80 so as to be drawable. The transfer paper S stored in these paper feed cassettes 9A and 9B is selectively sent out by the rotation of the corresponding paper feed rollers 10A and 10B, and is fed by the separation rollers 11A and 11B and the transport roller pairs 12A and 12B. It is sent to the paper transport path P1.

  A registration roller pair 13 including a pair of rollers is provided in the paper feed conveyance path P1 in order to take a feeding timing for feeding the transfer paper S to the secondary transfer nip. The transfer sheet S is conveyed from the registration roller pair 13 toward a secondary transfer nip formed by the intermediate transfer belt 6a and the secondary transfer roller 14a.

  The printer 500 includes a manual tray 25 as a manual paper feed unit on the right side in FIG. 1, and the manual tray 25 is rotated when not in use, and a side frame F that is a part of the printer 500 main body. It can be stored in. The uppermost transfer sheet S placed on the manual feed tray 25 is fed by the manual feed roller 26 and then separated by a reverse roller 27 as a separation means so as to be reliably conveyed by one sheet. The roller 22 and the roller 24 are sent to the registration roller pair 13 through the paper feed conveyance path P1.

  A fixing device 15 having a heating unit is provided above the secondary transfer nip. The fixing device 15 includes a fixing roller 15a having a built-in heater, and a pressure roller 15b that contacts the fixing roller 15a while applying pressure. As the fixing device 15, a device using a belt, a device using a heating method by IH (Induction Heating), or the like can be appropriately used. After the fixing, the transfer sheet S is guided by a guide member 61a that forms a paper discharge path by switching the direction of a switching guide 63 that is rotatably provided to the direction of the paper discharge roller 62 as shown in FIG. The paper is discharged by the rotation of the paper discharge roller 62 and stacked on the paper discharge tray 60 at the top of the printer 500.

  The printer 500 includes a duplex unit including a refeed path and a roller for reversing and refeeding the transfer sheet S so that images can be formed on both sides of the transfer sheet S.

  Specifically, a switchback conveyance path P5 and a refeed conveyance path P6 are provided in the side frame F, and the transfer sheet S on which image formation on one side is finished is conveyed to the sheet conveyance path P1. A switching guide 63, a second switching guide G2, and a third switching guide G3 are provided. Further, a reversing roller 18a, a reversing roller 22 and the like which are connected to a driving source (not shown) and can be reversed by controlling the driving source are provided. A roller 23 and a roller 24 are in contact with the reversing roller 22, and when the reversing roller 22 rotates clockwise, the transfer paper S is conveyed from the manual feed tray 25 by the cooperation of the reversing roller 22 and the roller 24. When the reverse roller 22 rotates counterclockwise, the transfer paper S in the refeed conveyance path P6 is refeeded in the direction of the registration roller pair 13 by the cooperation of the reverse roller 22 and the roller 23. It has become so.

  When the switching guide 63 rotates in the clockwise direction from the state of FIG. 1, the transfer sheet S after fixing is guided to the reverse conveyance path P4 by the roller pair 17, and to the reverse roller pair 18 through the second switching guide G2. It is transported and once sent to the switchback transport path P5. After the transfer paper S is sent to the switchback conveyance path P5, the reverse roller 18a of the reverse roller pair 18 rotates counterclockwise, and the second switching guide G2 rotates counterclockwise, thereby transferring the transfer paper. S is sent from the switchback transport path P5 to the refeed transport path P6. The transfer sheet S conveyed to the refeed conveyance path P6 is conveyed by the rollers 15c and 20 and the rollers 14c and 21, and further conveyed by the reverse roller 22 and the roller 23 so as to reach the registration roller pair 13. It has become.

  The printer 500 includes a paper feeding device 50 as an additional paper feeding unit below the paper feeding unit 300. The paper feeding device 50 shown in FIG. 1 includes two paper feeding cassettes 9C and 9D. However, the number of transfer sheets S can be increased by increasing the number of paper feeding cassettes 9C and 9D. You may comprise so that the total accommodation number of sheets of the transfer paper S may be increased by increasing a capacity | capacitance.

  In the printer 500, the third switching guide G3 disposed above the fixing device 15 and downstream in the conveying direction of the roller pair 17 rotates counterclockwise from the state shown in FIG. The transfer paper S can be discharged to another paper discharge device (not shown) by guiding S and transporting the transfer paper S to the paper discharge path P8. Another paper discharge device is, for example, a bin tray having several stages of paper discharge trays.

Here, an operation during single-sided printing in which an image is formed on one side of the transfer paper S will be described.
First, the surface of the photoreceptor 2Y uniformly charged by the charging roller 4aY is irradiated with laser light 8Y corresponding to yellow image data emitted from a semiconductor laser light source (not shown) by the operation of the exposure device 80. As a result, an electrostatic latent image is formed on the surface of the photoreceptor 2Y. This electrostatic latent image is developed with yellow toner after being developed by the developing roller 5aY to become a visible image. The visible image developed with the yellow toner is primarily transferred to the surface of the intermediate transfer belt 6a that moves in synchronization with the photoreceptor 2Y under the transfer action of the primary transfer roller 7Y. Such latent image formation, development, and primary transfer operations are sequentially performed in the same manner for the other photoreceptors 2 (C, M, and Bk) at the same timing.

  As a result, yellow Y, cyan C, magenta M, and black Bk toner images are carried on the surface of the intermediate transfer belt 6a as sequentially overlapping four-color toner images. Are conveyed together with the intermediate transfer belt 6a moving in the direction (counterclockwise). On the other hand, the remaining toner and foreign matter are cleaned by the cleaning device 3 on the surface of the photoreceptor 2 that has passed through a position facing the primary transfer roller 7 with the intermediate transfer belt 6a interposed therebetween.

  The four-color toner image formed on the intermediate transfer belt 6a is transferred onto the transfer sheet S conveyed in synchronization with the intermediate transfer belt 6a by receiving a transfer action by the secondary transfer roller 14a. The surface of the intermediate transfer belt 6a is cleaned by a belt cleaning device 6h to prepare for the next image forming process and transfer process. The transfer sheet S on which the image has been transferred is subjected to a fixing action by the fixing device 15 and then discharged to the discharge tray 60 by the discharge roller 62 with the image surface facing downward (face down).

Next, an operation during double-sided printing in which images are formed on both sides of the transfer paper S will be described.
The transfer sheet S on which the image is transferred from the intermediate transfer belt 6a to one side thereof by the same action as in the above-described single-side printing passes through the fixing device 15 and is subjected to the fixing action, and then to the roller pair 17 by the switching guide 63. Guided towards. The transfer sheet S guided toward the roller pair 17 is disposed at the rotation position shown in FIG. 1 through a third switching guide G3 and a reverse conveyance path P4 provided on the downstream side in the conveyance direction of the roller pair 17. It proceeds above the second switching guide G2 and is conveyed to the switchback conveyance path P5 by the reverse roller pair 18. At this time, the reverse roller 18a is driven to rotate clockwise. The roller pair 19 capable of forward / reverse rotation in the switchback transport path P5 is reversely rotated after the transfer paper S is once received by the switchback transport path P5 by forward rotation, and reversely transports the transfer paper S. When the rotation directions of the roller pair 19 and the reverse roller pair 18 are reversed, the second switching guide G2 rotates counterclockwise from the posture shown in FIG. Then, the transfer paper S is fed into the refeed conveyance path P6 by the rollers 15c and 20 and the rollers 14c and 21, with the end that was the rear end until entering the switchback conveyance path P5 of the transfer paper S as the leading edge. The paper is conveyed toward the paper conveyance path P1 and reaches the registration roller pair 13. Thereafter, the transfer sheet S having an image on one side is conveyed again toward the secondary transfer nip where the secondary transfer roller 14a and the intermediate transfer belt 6a face each other at a timing by the registration roller pair 13. The toner image on the intermediate transfer belt 6a is transferred to the other side of the transfer sheet S.

  Images to be formed on the second surface of the transfer paper S are sequentially formed by an image forming process that is started when the transfer paper S is conveyed to a predetermined position. The image forming process in this case is also the same as the above-described full-color toner image formation during single-sided printing, and this full-color toner image is carried on the intermediate transfer belt 6a. However, since the front and back of the transfer sheet S are reversed, the creation of the image data emitted from the exposure device 80 is controlled so that the image is formed in the reverse direction in the sheet conveyance direction with respect to the first image formed. The

  The transfer sheet S on which the full-color toner images are transferred on both sides in this way is subjected to fixing processing by the fixing device 15 again, and is discharged onto the discharge tray 60 by the discharge roller 62.

  In the printer 500, in order to increase the time efficiency of double-sided printing, the conveyance of the transfer sheet S is controlled so that several transfer sheets S are simultaneously conveyed in the conveyance path. The timing for forming images on the front and back sides of the transfer paper S is controlled by a control means (not shown).

  In the printer 500, the polarity of the toner image formed on the photoconductor 2 is negative. By applying a positive charge to the primary transfer roller 7, the toner image on the photoconductor 2 is transferred to the intermediate transfer belt 6a. It is designed to be transferred to the surface. Further, the toner image on the surface of the intermediate transfer belt 6a is transferred onto the transfer paper S by applying a positive charge to the secondary transfer roller 14a.

  In addition, although the example which performs full color printing regarding these single-sided printing and double-sided printing operation was demonstrated, when performing monochrome printing by black Bk, the photoreceptor 2 (Y, M corresponding to yellow Y, cyan C, and magenta M) , C) is not used. For this reason, when performing monochrome printing with black Bk, not only the unused photoreceptor 2 (Y, M, C) and developing device 5 (Y, M, C) are operated, but these unused photoreceptors are also used. The printer 500 includes a mechanism for keeping 2 (Y, M, C) and the intermediate transfer belt 6a in a non-contact state. That is, in the printer 500, the inner frame 6f that supports the roller 6d and the primary transfer rollers 7Y, 7C, and 7M is supported so as to be rotatable about the frame shaft 6g. 2 (Y, M, C) is rotated in a direction (clockwise in FIG. 1), and the image forming process is executed in a state where only the photosensitive member 2Bk is in contact with the intermediate transfer belt 6a, whereby monochrome using black toner is performed. Create an image. As described above, during monochrome printing, the photoreceptor 2 (Y, M, C) of the image forming unit 1 (Y, M, C) that is not used is separated from the intermediate transfer belt 6a, and the photoreceptor 2 (Y, M, C) is separated. By stopping C) and the developing device 5 (Y, M, C), the life of the image forming unit 1 (Y, M, C) can be improved.

  In the printer 500, maintenance such as component replacement is performed by opening an exterior cover (not shown). It is possible to improve the operability in maintenance by configuring the process cartridge as a unit by integrally supporting the members of the image forming unit 1 shown in FIG. 2 and replacing the process cartridge during maintenance. .

  When the image forming unit 1 shown in FIG. 2 is configured as a process cartridge, the process cartridge can be easily attached to and detached from the printer 500 by providing a guide unit and a handle for mounting the printer 500 on the process cartridge. be able to. Further, by providing the process cartridge with a storage device (for example, an IC tag) for storing the characteristics and operation status of the process cartridge, it is possible to improve the convenience in maintenance of the process cartridge.

  Further, if the intermediate transfer unit 6 is pulled out from the main body of the printer 500 with the intermediate transfer belt 6a and each photoconductor 2 being separated from each other, the operability in maintenance of the intermediate transfer unit 6 can be improved.

  As shown in FIG. 3, the duplex unit 30 and the secondary transfer unit 14 are provided on a side frame F that can rotate with respect to the printer 500 about the rotation axis Fa. The duplex unit 30 and the secondary transfer unit 14 can be opened upward as shown in FIG. 3 by rotating the side frame F clockwise from the state of FIG. The side frame F includes a stopper member (not shown), and the stopper member can be rotated by being rotated by an operation of a lock lever (not shown) and removed from a blocking member (not shown) provided on the printer 500 side. It is supposed to become a state. In this way, by opening the side frame F, a plurality of transport paths (P1, P2, P6) can be opened, and jams (paper jams) occur in these transport paths (P1, P2, P6). Treatment such as removal of the transfer paper S can be easily performed.

  A secondary transfer unit 14 is provided between the post-transfer conveyance path P2 and the switchback conveyance path P5. The secondary transfer unit 14 includes a secondary transfer roller 14a, and rotates about the roller 23 as a rotation center. The secondary transfer roller 14a is separated from the intermediate transfer belt 6a when the side frame F is opened as shown in FIG. Further, the secondary transfer unit 14 is given a turning behavior so that the roller 14 c is separated from the roller 21. The secondary transfer unit 14 includes a power source 14b inside, and has a transfer function of the transfer paper S such as the secondary transfer roller 14a and rollers 14c and 23 on the outside.

  The fixing device 15 has a conveyance roller 15c and a conveyance guide surface, and the right side surface forms a refeed conveyance path P6. The fixing device 15 is supported so that it can be pulled out in the right direction in the figure in the state shown in FIG. For this reason, it is possible to easily perform processing such as removal of the transfer paper S in which a jam (paper jam) has occurred inside the fixing device 15.

  Further, a projection (not shown) is provided on the upper surface of the side frame F, and this projection moves the side frame F in a closing direction so that the secondary transfer unit 14 and the duplex unit 30 can be mounted on the printer 500. At this time, it engages with an engaging portion (not shown).

  The conveying roller 15c is urged toward the roller 20 by a spring (not shown), and the roller 14c is urged toward the roller 21 by a spring (not shown). Further, the rollers 12Ab and 12Bb on the printer 500 side of the transport roller pairs 12A and 12B are biased by springs (not shown) toward the rollers 12Aa and 12Ba on the side frame F side of the transport roller pairs 12A and 12B.

  For this reason, when the side frame F is in the closed position shown in FIG. 1, the side frame F is not shown in the direction to be opened by the rollers 12Ab and 12Bb on the printer 500 side of the rollers 15c and 14c and the conveying roller pairs 12A and 12B. It is biased by a spring. As a result, the stopper surface of the stopper member and the blocking member come into contact with each other to position the side frame F. That is, the rollers 12Ab and 12Bb on the printer 500 side of the rollers 15c and 14c and the conveying roller pair 12A and 12B are arranged such that the side frame F is attached to the printer 500 by the stopper member on the side frame F side and the blocking member on the printer 500 main body side. It functions as an urging device for positioning.

Next, with reference to FIGS. 4 to 8, the configuration of the pull-in device accommodated in the paper feeding device 50 of the printer 500 (see FIG. 1) will be described.
First, a schematic configuration of the retracting device will be described with reference to FIGS. 4 and 5.

  As shown in FIG. 4, the pull-in device 301 is interposed between the guide rail 310 fixed to the main body of the paper feeding device 50 in the printer 500 (see FIG. 1), and the paper feeding cassette 9C and the guide rail 310. The first fitting roller 320 and the second fitting roller 330, the pull-in unit 340 interposed between the sheet feeding cassette 9C and the main body of the sheet feeding device 50 (see FIG. 1), and the sheet feeding cassette 9C And a stopper member 390 that restricts drawing and drawing with a predetermined drawing width.

  The guide rail 310, the first fitting roller 320, the second fitting roller 330, and the stopper member 390 are provided on both the left and right sides of the sheet feeding cassette 9C. Only the configuration on the right side as viewed from the above will be described.

  As shown in FIG. 4, the guide rail 310 is formed of a sheet metal that is integrally formed, and includes a guide rail side plate 311, a guide rail top plate 314, a guide rail fitting plate 315, and a guide. Rail lower surface plate 317.

  The guide rail side plate 311 is fixed to the main body of the paper feeding device 50 (see FIG. 1) by screwing. Moreover, the side plate 311 for guide rail has the roller support part 311s (end part by the side of the drawer in the main body apparatus) formed so that the side surface of the 2nd fitting roller 330 might be covered, FIG. As shown in c), a shaft hole 312 is formed in the roller support portion 311s.

  The guide rail upper surface plate 314 is configured by a flat plate formed perpendicular to the guide rail side surface plate 311 at the end of the guide rail side surface plate 311 on the paper feed cassette 9B (see FIG. 1) side.

  The guide rail fitting plate 315 is composed of a flat plate formed perpendicularly to the guide rail upper surface plate 314 at the inner end portion of the guide rail upper surface plate 314, and its longitudinal dimension is based on a stroke α to be described later. Is also configured to be larger.

  Further, the guide rail fitting plate 315 has a guide rail fitting portion 315f that fits into a first fitting groove portion described later of the first fitting roller 320. The guide rail fitting portion 315f corresponds to a portion of the guide rail fitting plate 315 that fits into a first fitting groove portion described later.

  The guide rail lower surface plate 317 is configured by a flat plate formed perpendicular to the guide rail side plate 311 at the end of the guide rail side plate 311 on the paper feed cassette 9D (see FIG. 1) side.

  Here, the main body, the guide rail side plate 311, the guide rail upper surface plate 314, and the guide rail lower surface plate 317 according to the present embodiment are included in the present invention. The main body device is configured. Further, the guide rail fitting plate 315 according to the present embodiment constitutes a guide member according to the present invention. Furthermore, the guide rail fitting portion 315f according to the present embodiment constitutes a fitting portion according to the present invention.

  The guide rail side plate 311, the guide rail upper surface plate 314, the guide rail fitting plate 315, and the guide rail lower surface plate 317 are described as being integrally formed, but these are formed separately. Each member may be connected via a connecting member such as a hinge.

  The first fitting roller 320 is supported by a first fitting roller shaft 321 fixed to a slide rail, which will be described later, by screwing, and a first fitting roller shaft 321 that is rotatable and non-movable in the axial direction. And a fitting wheel 323.

  The first fitting wheel 323 is made of a resin mainly composed of polyacetal. The first fitting wheel 323 has a columnar first columnar wheel 324, a truncated cone-shaped first truncated cone wheel 325, a first columnar wheel 324, A first connecting wheel 326 that connects the one truncated cone wheel 325;

  The second fitting roller 330 is fixed to the shaft hole 312 of the guide rail side plate 311 by screwing, and is rotatable to the second fitting roller shaft 331 and cannot move in the axial direction. And a second fitting wheel 333 supported by the motor.

The second fitting wheel 333 is made of a resin mainly composed of polyacetal. The second fitting wheel 333 has a cylindrical second cylindrical wheel 334, a second truncated cone wheel 335, a second cylindrical wheel 334, and a second cylindrical wheel 334. And a second connecting wheel 336 that connects the two truncated cone wheels 335.
Here, the 1st fitting wheel 323 and the 2nd fitting wheel 333 which concern on this Embodiment each comprise the rotary body which concerns on this invention.

  The pull-in unit 340 is for pulling in the paper feed cassette 9C. The detailed configuration of the pull-in unit 340 will be described later.

  As shown in FIG. 5, the paper feed cassette 9C is constituted by a drawer-type paper feed cassette, and is formed in a pair of support portions 361, 362 formed in a hollow bar shape, a grip portion 363, and a substantially flat plate shape. The tray unit 365 is provided.

The support part 361 is configured to accommodate the first sliding roller 380 and the second sliding roller 383 in a rotatable manner. The support portion 361 is supported by the slide rail 370 via the first sliding roller 380 and the second sliding roller 383. Further, wheel holes 361 a and wheel holes 361 b corresponding to the first sliding roller 380 and the second sliding roller 383 are formed on the upper surface and the lower surface of the support portion 361. In addition, since the support part 362 is comprised substantially symmetrically with the support part 361, description is abbreviate | omitted.
The grip portion 363 has a handle 364.

  The tray unit 365 supports a bottom plate (not shown) configured to be swingable to push up the stored transfer sheet S, and one end of the transfer sheet S. The tray unit 365 supports the first fitting wheel 323 and the second fitting wheel 333. An end fence 367 that restricts the movement of the transfer sheet S in the thrust direction, and a pair of side guides 368a and 368b that restrict the movement of the transfer sheet S in the pull-out direction and the pull-in direction of the paper feed cassette 9C. Yes. Further, the end fence 367 and the side guides 368a and 368b are configured to be position adjustable according to the size of the transfer sheet S.

  The slide rail 370 is constituted by an integrally formed sheet metal, and is interposed between the paper feed cassette 9C and the guide rail 310 (see FIG. 4). The slide rail 370 includes a slide rail side plate 371, a slide rail upper plate 375, a slide rail lower plate 376, and a slide rail fitting plate 377.

  The slide rail side plate 371 includes a main body portion 371h and a roller support portion 371s (an end portion on the side of the unit in the unit) formed in the extending direction of the main body portion 371h. A shaft hole 372 is formed, and a shaft hole 373 is formed in the roller support portion 371s.

  The slide rail upper surface plate 375 is configured by a flat plate formed perpendicularly to the slide rail side plate 371 at the end of the slide rail side plate 371 on the paper feed cassette 9B (see FIG. 1) side. The slide rail lower surface plate 376 is constituted by a flat plate formed perpendicular to the slide rail side plate 371 at the end of the slide rail side plate 371 on the side of the paper feed cassette 9D (see FIG. 1).

  The slide rail fitting plate 377 is composed of a flat plate formed perpendicularly to the slide rail lower surface plate 376 at the inner end of the slide rail lower surface plate 376, and has a longitudinal dimension based on a stroke α to be described later. Is also configured to be larger.

  The slide rail fitting plate 377 has a slide rail fitting portion 377 f that fits into a second fitting groove portion of the second fitting roller 330 described later. The slide rail fitting portion 377f corresponds to a portion of the slide rail fitting plate 377 that fits into a second fitting groove portion described later. Here, the slide rail fitting plate 377 according to the present embodiment constitutes a guide member according to the present invention. Further, the slide rail fitting portion 377f constitutes a fitting portion according to the present invention.

  The first sliding roller 380 is accommodated in the support portion 361 of the paper feed cassette 9C, and is rotated to the first sliding roller shaft 381 and the first sliding roller shaft 381 fixed to the support portion 361 by screwing. And a first sliding wheel 382 supported so as to be movable in the axial direction.

  The first sliding wheel 382 is made of a resin formed in a cylindrical shape, partially protrudes from a wheel hole 361a formed in the paper feed cassette 9C, and comes into contact with the slide rail lower surface plate 376. ing. As a result, the first sliding wheel 382 rotates in accordance with the relative movement between the paper feed cassette 9C and the slide rail 370.

  The second sliding roller 383 is accommodated in the support portion 361 of the paper feed cassette 9C, and rotates to the second sliding roller shaft 384 fixed to the support portion 361 by screwing and the second sliding roller shaft 384. And a second sliding wheel 385 supported so as not to be axially movable.

  The second sliding wheel 385 is made of a resin formed in a cylindrical shape, partially protrudes from the wheel hole 361b formed in the paper feed cassette 9C, and comes into contact with the slide rail lower surface plate 376. ing. As a result, the second sliding wheel 385 rotates in accordance with the relative movement between the paper feed cassette 9C and the slide rail 370.

  The third sliding roller 386 is interposed between the guide rail 310 and the slide rail 370 and has a third sliding roller shaft 387 fixed to the shaft hole 372 by screwing, and a third sliding roller shaft. 387 has a third sliding wheel 388 supported rotatably and not axially movable.

  The third sliding wheel 388 is made of a resin formed in a cylindrical shape, and comes into contact with the guide rail lower surface plate 317 of the guide rail 310. Thereby, the third sliding wheel 388 rotates with the relative movement of the guide rail 310 and the slide rail 370.

Here, the sheet tray 9C of the present embodiment, a slide rail for the side surface plate 371, the upper plate 375 sliding rail, a fitting plate 377 sliding rail, the first sliding roller 380, second The sliding roller 383 constitutes a unit according to the present invention.
The slide rail 370, the first sliding roller 380, the second sliding roller 383, and the third sliding roller 386 are provided substantially symmetrically on the left and right sides when viewed from the front of the paper feed cassette 9C. Here, only the configuration on the right side when viewed from the front of the sheet feeding cassette 9C will be described.

  As shown in FIG. 4C, the stopper member 390 includes a guide rail side first stopper 391 and a guide rail side second stopper 392 provided on the surface of the guide rail upper surface plate 314 on the slide rail upper surface plate 375 side. A slide rail side upper stopper 393 provided on the surface of the slide rail upper surface plate 375 on the guide rail upper surface plate 314 side, and a slide rail provided on the surface of the slide rail upper surface plate 375 on the paper feed cassette 9C side. A side lower stopper 394 and a sheet feeding cassette side stopper 395 provided on the surface on the slide rail upper surface plate 375 side of the support portion 361 are configured.

  The guide rail side first stopper 391 and the slide rail side upper stopper 393 are engaged with each other when the slide rail 370 moves in the pulling-out direction of the sheet feeding cassette 9C to restrict the pulling of the slide rail 370, and the slide rail 370 Is prevented from slipping out of the guide rail 310.

The guide rail side second stopper 392 and the slide rail side upper stopper 393 are engaged with each other when the slide rail 370 moves in the pull-in direction of the paper feed cassette 9C to restrict the pull-in of the slide rail 370. Yes.
Here, the guide rail side first stopper 391, the guide rail side second stopper 392, and the slide rail side upper stopper 393 according to the present embodiment constitute a limiting member according to the present invention.

  The slide rail side lower stopper 394 and the paper feed cassette side stopper 395 engage with each other when the paper feed cassette 9C is pulled out with respect to the slide rail 370, thereby restricting the drawer of the paper feed cassette 9C. 9C is prevented from slipping out of the slide rail 370. In addition, when the paper feed cassette 9C is retracted, the gripper 363 (see FIG. 5) engages with the main body of the paper feed device 50 (see FIG. 1) to limit the pull-in of the paper feed cassette 9C. It is like that.

  Here, if the distance between the guide rail side first stopper 391 and the guide rail side second stopper 392 is α, the slide rail 370 moves within the range of the stroke α corresponding to the drawing width of the paper feed cassette 9C. It moves in the pull-out direction and the pull-in direction.

  Further, the paper feed cassette 9C slides in the pulling direction with respect to the slide rail 370 until the slide rail side lower stopper 394 and the paper feed cassette side stopper 395 are engaged. For this reason, the maximum drawer width of the paper feed cassette 9C is determined by the sum of the stroke α corresponding to the drawer width of the slide rail 370 with respect to the guide rail 310 and the drawer width of the paper cassette 9C with respect to the slide rail 370.

  Here, since the longitudinal dimension of the guide rail fitting plate 315 is larger than the stroke α, the guide rail fitting plate 315 is engaged with the first fitting wheel 323 throughout the stroke α of the paper feed cassette 9C. It comes to match.

  In addition, since the longitudinal dimension of the slide rail fitting plate 377 is larger than the stroke α, the slide rail fitting plate 377 is engaged with the second fitting wheel 333 in the entire region of the stroke α of the sheet feeding cassette 9C. It is supposed to be.

  In addition, when the slide rail side lower stopper 394 and the paper feed cassette side stopper 395 are engaged with each other, the grip portion 363 of the paper feed cassette 9C is lifted by the user, and the paper feed cassette 9C is inclined with respect to the slide rail 370. When this is done, the engagement is released. As a result, the paper feed cassette 9C can be detached from the slide rail 370.

  Further, in the state where the first guide rail side stopper 391 and the slide rail side upper stopper 393 are engaged with each other, the end of the slide rail 370 on the drawer side of the paper feed cassette 9C is lifted by the user, and the slide rail 370 is moved. When tilted with respect to the guide rail 310, the engagement is released. Thereby, the slide rail 370 can be removed from the guide rail 310.

  The guide rail side first stopper 391, the guide rail side second stopper 392, the slide rail side upper stopper 393, the slide rail side lower stopper 394, and the paper feed cassette side stopper 395 are provided in the main body of the paper feeding device 50. It is also possible to employ a stopper that can be switched between engagement and release by operating a switch.

  Next, with reference to FIG. 6A, a configuration around the fitting portion between the first fitting roller 320 and the guide rail 310 will be described.

  As shown in FIG. 6A, the first fitting wheel 323 of the first fitting roller 320 has a first fitting groove 327 formed in the circumferential direction on the circumferential surface thereof. The first fitting groove 327 includes a first cylinder-side fitting surface 324a formed on the first truncated cone wheel 325 side of the first cylindrical wheel 324, and a first cone so as to face the first cylinder-side fitting surface 324a. The first truncated cone side fitting surface 325a formed on the pedestal wheel 325 and the outer peripheral surface 326a of the first connecting wheel 326 are configured.

The groove width of the first fitting groove 327 represented by the distance between the first cylindrical side fitting surface 324a and the first truncated cone side fitting surface 325a is L, and the thickness of the guide rail fitting plate 315 is t. Assuming that the gap (backlash) between the first cylinder side fitting surface 324a and the first truncated cone side fitting surface 325a and the guide rail fitting plate 315 in the first fitting groove 327 is A, the following formula ( 1) is established.
A = L−t (1)

  Next, with reference to FIG. 6B, the configuration around the fitting portion between the second fitting roller 330 and the slide rail 370 will be described.

  As shown in FIG. 6B, the second fitting wheel 333 of the second fitting roller 330 has a second fitting groove 337 formed in the circumferential direction on the circumferential surface thereof. The second fitting groove 337 includes a second circular cylinder side fitting surface 334a formed on the second circular truncated cone wheel 335 side of the second cylindrical wheel 334, and a second circular cone so as to face the second cylindrical side fitting surface 334a. A second frustoconical side fitting surface 335 a formed on the pedestal wheel 335 and an outer peripheral surface 336 a of the second connection wheel 336 are configured. In the second fitting groove portion 337 as well, the relationship represented by the expression (1) is established, similarly to the first fitting groove portion 327 described above.

  Here, the 1st fitting groove part 327 and the 2nd fitting groove part 337 which concern on this Embodiment each comprise the groove part which concerns on this invention. Further, the first cylindrical side fitting surface 324a and the first truncated cone side fitting surface 325a, and the second cylindrical side fitting surface 334a and the second truncated cone side fitting surface 335a are the fitting surfaces according to the present invention. Each is composed.

  As described above, the guide rail fitting portion 315f and the first fitting groove portion 327, and the slide rail fitting portion 377f and the second fitting groove portion 337 are respectively provided on the left and right sides when viewed from the front of the sheet feeding cassette 9C. By fitting, the slide rail 370 is supported at a total of four locations with respect to the guide rail 310, and is guided in the drawing direction and the drawing direction of the sheet feeding cassette 9C.

  Further, the gap A is different between the right and left fitting positions when viewed from the front of the sheet feeding cassette 9C. Specifically, since the positioning of the paper feed cassette 9C in the thrust direction of the first fitting wheel 323 and the second fitting wheel 333 is performed on the right side when viewed from the front of the paper feeding cassette 9C, The gap A at the fitting location is set smaller than the gap A at the left fitting location. Accordingly, when the slide rail 370 is set on the guide rail 310 while the sliding resistance and the clearance are reduced by the first fitting wheel 323 and the second fitting wheel 333, Interference with the fitting plate can be suppressed. The gap A at the right fitting location may be set larger than the gap A at the left fitting location.

Next, the configuration of the pull-in unit 340 will be described with reference to FIGS.
As shown in FIG. 7, the pull-in unit 340 is interposed between the paper feed cassette 9 </ b> C and the main body of the paper feed device 50, a guide plate 341 fixed to the main body of the paper feed device 50, and a paper feed And an engaging protrusion 344 provided on the cassette 9C.

  FIG. 8 shows the internal structure of the pull-in unit 340 from the direction of the paper feed cassette 9D (see FIG. 1). The pull-in unit 340 includes a base member (not shown) fixed to the main body of the paper feeding device 50 (see FIG. 1), a guide plate 341 fixed to the base member, the engagement protrusion 344, the first lever 345, and the like. , Second lever 346, first spring 348, second spring 349, first gear 350, second gear 351, claw 352, speed-dependent damper 353, and damper holder 354. .

  The guide plate 341 has a guide groove portion 342 formed so as to extend in the attaching / detaching direction of the sheet feeding cassette 9C (see FIG. 7). The guide groove portion 342 is inclined so as to be opposed to each other so that the guide surfaces 342a and 342b formed so as to face each other with a predetermined groove width and the guide surfaces 342a and 342b are continuously widened. It has surfaces 342c and 342d, and guides the engaging protrusion 344. Here, the guide plate 341 according to the present embodiment constitutes an engaging member according to the present invention.

  The engagement protrusion 344 is made of a member formed in a cylindrical shape, and protrudes from the lower surface of the tray portion 365 (see FIG. 7) of the sheet feeding cassette 9C. Further, the engagement protrusion 344 is configured such that its diameter is slightly smaller than the groove width of the guide groove portion 342, that is, the distance between the guide surface 342a and the guide surface 342b. There is almost no gap between the guide surfaces 342a and 342b. Here, the engaging protrusion 344 according to the present embodiment constitutes an engaged member according to the present invention.

  The first lever 345 is configured by a plate-like member, and includes a rotation support portion 345a, a spring support portion 345b, and a claw support portion 345c. Further, the first lever 345 is configured to be rotatable on the guide plate 341 with the rotation support portion 345a as a fulcrum.

  The second lever 346 is configured by a plate-like member bent at a predetermined angle, and includes a rotation support portion 346a, a first spring support portion 346b, and a second spring support portion 346c. The second lever 346 is configured to be rotatable on the guide plate 341 with the rotation support portion 346a as a fulcrum.

  The first spring 348 is configured by a coil spring, and engages with a first lever engagement portion 348 a that engages with a spring support portion 345 b of the first lever 345 and a first spring support portion 346 b of the second lever 346. A second lever engaging portion 348b. Further, the first spring 348 biases the spring support portion 345b and the first spring support portion 346b so as to attract each other.

  The second spring 349 is constituted by a coil spring, and a second end that engages with a base end portion 349 a fixed to the inlet side end portion of the guide groove portion 342 of the guide plate 341 and a second spring support portion 346 c of the second lever 346. And a lever engaging portion 349b. Further, the second spring 349 biases the second spring support portion 346c of the second lever 346 in the direction of the inlet side end portion of the guide groove portion 342.

  The first spring 348 and the second spring 349 have been described as being configured by coil springs, but are not limited thereto, and may be configured by an elastic member such as a leaf spring or rubber.

  The first gear 350 is constituted by a substantially semi-disc gear, and is connected to the first lever 345 so as to rotate integrally with the first lever 345. The second gear 351 is connected to a latch gear (not shown) that meshes with the first gear 350, and rotates integrally with the latch gear. Further, the second gear 351 meshes with the damper gear of the speed dependent damper 353.

  The speed-dependent damper 353 is configured by a known speed-dependent damper unit, and increases or decreases a load that decreases the rotational speed of the second gear 351 according to the magnitude of the rotational speed of the second gear 351. It is like that. Specifically, the speed-dependent damper 353 increases the load that decreases the rotation speed of the second gear 351 as the rotation speed of the second gear 351 increases.

  The damper holder 354 is fixed to the guide plate 341 and has a locking portion 354a. The damper holder 354 is configured to fix the speed dependent damper 353.

  As shown in FIG. 9, the claw 352 includes a locking portion 352 a, a rotation support portion 352 b that engages with the claw support portion 345 c of the first lever 345, and a protrusion engagement portion 352 c that engages with the engagement protrusion 344. It is configured to rotate on the guide plate 341 with the rotation support portion 352b as a fulcrum.

  As shown in FIG. 10, when the engaging protrusion 344 does not press the protrusion engaging portion 352 c, the retracting unit 340 locks the engaging portion 352 a of the claw 352 with the engaging portion 354 a of the damper holder 354. It has become.

  As shown in FIG. 11, when the engaging projection 344 guided by the guide groove 342 presses the projection engaging portion 352c, the retracting unit 340 uses the rotation support portion 352b as a fulcrum and the claw 352 as the timepiece in FIG. By rotating around, the locking between the locking portion 352a of the claw 352 and the locking portion 354a of the damper holder 354 is released. As a result, the pull-in unit 340 uses the biasing force of the first spring 348 to pull the engagement protrusion 344 along the guide groove 342 in the mounting direction of the paper feed cassette 9C.

  As shown in FIG. 12, the retracting unit 340 rotates the second lever 346 by the biasing force of the first spring 348 when the engaging protrusion 344 is guided to the guide groove 342 and retracted to a predetermined balance position. The moment and the rotational moment of the second lever 346 due to the urging force of the second spring 349 are balanced.

  When the engaging protrusion 344 is further pulled from the balanced position shown in FIG. 12 in the mounting direction of the sheet feeding cassette 9C, the pulling unit 340 receives the rotational moment of the second lever 346 due to the biasing force of the first spring 348. However, since the rotational moment of the second lever 346 due to the biasing force of the second spring 349 becomes larger, the second lever 346 is rotated counterclockwise in FIG. Thereby, the pull-in unit 340 further pulls the claw 352 in the mounting direction of the paper feed cassette 9C via the first spring 348 in accordance with the rotation of the second lever 346, and thereby via the protrusion engaging portion 352c of the claw 352. Thus, the engaging protrusion 344 is retracted to the retracting completion position shown in FIG.

  On the other hand, the pull-in unit 340 moves the claw 352 in the pull-out direction via the engagement protrusion 344 when the paper feed cassette 9C is pulled out, thereby moving the second lever 346 via the first spring 348 in FIG. It is designed to rotate clockwise. Accordingly, the pull-in unit 340 extends the second spring 349 and extends the first spring 348 by further pulling out the paper feed cassette 9C. For this reason, the pull-in unit 340 stores the urging force for pulling in the paper feed cassette 9C in the first spring 348 and the second spring 349 when the paper feed cassette 9C is pulled out.

Next, with reference to FIG. 14, the positional relationship between the guide groove portion 342 and the engaging protrusion 344 in the retracting unit 340 will be described. As shown in FIG. 14, when the diameter of the engaging protrusion 344 is r, the relationship between the gap A obtained by the expression (1) and the diameter r of the engaging protrusion 344 is obtained by the following expression (2). It is done.
r / 2> A (2)

  As described above, the retracting device 301 according to the present embodiment is rotatable on the first fitting wheel 323 rotatably attached to the roller support portion 371 s of the slide rail 370 and the roller support portion 311 s of the guide rail 310. The attached second fitting wheel 333, the slide rail fitting plate 377 that engages with the first fitting wheel 323 and guides the paper feed cassette 9 </ b> C in the drawing direction and the drawing direction, and the second fitting wheel 333 A guide rail fitting plate 315 that engages and guides the sheet feeding cassette 9C in the pulling-out direction and the drawing-in direction is provided, so that the first fitting wheel is in a direction perpendicular to the drawing-out direction and the drawing-in direction of the sheet feeding cassette 9C. The movement of the sheet feeding cassette 9C in the thrust direction of the H.323 and the second fitting wheel 333 can be restricted. In addition, the first fitting wheel 323 and the second fitting wheel 333 rotate when the paper feeding cassette 9C is pulled out and retracted, so that the paper feeding cassette 9C with respect to the main body of the paper feeding device 50 is compared with the conventional case. The sliding resistance can be reduced. Further, by restricting the movement of the sheet feeding cassette 9C in the thrust direction of the first fitting wheel 323 and the second fitting wheel 333, the posture of the sheet feeding cassette 9C can be stabilized. For this reason, when the guide plate 341 and the engaging protrusion 344 are engaged when the paper feed cassette 9C is pulled in, the positional relationship between the guide plate 341 and the engaging protrusion 344 can be maintained within a certain range. The collision load due to the contact between the surfaces 342c and 342d and the engaging protrusion 344 can be reduced.

  Therefore, the sliding resistance of the paper feed cassette 9C with respect to the main body of the paper feed device 50 can be reduced, and the collision load caused by the contact between the inclined surfaces 342c and 342d and the engagement protrusion 344 can be reduced. The operating force required for the operation can be reduced, and the operability of the paper feed cassette 9C can be improved.

  In addition, since the retractor 301 according to the present embodiment includes the first fitting wheel 323 and the second fitting wheel 333, the first fitting wheel 323, the guide rail fitting plate 315, and the second fitting The combination wheel 333 and the slide rail fitting plate 377 are engaged with each other. For this reason, the sliding resistance between the sheet feeding cassette 9 </ b> C and the body of the sheet feeding device 50 can be further reduced as compared with the case where one fitting wheel is provided. Further, the sheet feeding cassette in the direction perpendicular to the pulling-out direction and the drawing-in direction of the sheet feeding cassette 9C and the thrust direction of the first fitting wheel 323 and the second fitting wheel 333, compared to the case where one fitting wheel is provided. The movement of 9C can be more reliably regulated to stabilize the posture of the paper feed cassette 9C, and the collision load between the inclined surfaces 342c and 342d and the engaging protrusion 344 can be reduced.

  Therefore, since the operating force of the pull-in device 301 can be reduced more than when one fitting wheel is provided, the operability of the paper feed cassette 9C can be further improved.

  Further, in the retracting device 301 according to the present embodiment, the first fitting wheel 323 is provided on the roller support portion 371 s of the slide rail 370, and the second fitting wheel 333 is provided on the roller support portion 311 s of the guide rail 310. Therefore, compared with the case where the fitting roller is provided in one of the roller support portion 311s and the roller support portion 371s, the rotation of the paper feed cassette 9C in the horizontal direction when the paper feed cassette 9C is pulled out and retracted is reduced. It can be more strongly regulated.

  Therefore, the posture of the sheet feeding cassette 9C is stabilized and the collision load between the inclined surfaces 342c and 342d and the engaging protrusion 344 is more stable than when either one of the roller support portion 311s and the roller support portion 371s is provided with a fitting roller. Since the operation force of the pull-in device 301 can be reduced, the operability of the paper feed cassette 9C can be further improved.

  In the retracting device 301 according to the present embodiment, the first fitting wheel 323 has a first fitting groove 327 formed in the circumferential direction on the circumferential surface thereof, and the second fitting wheel 333 is The second fitting groove 337 is formed in the circumferential direction on the circumferential surface. Further, the guide rail fitting plate 315 has a guide rail fitting portion 315f that fits with the first fitting groove portion 327, and the slide rail fitting plate 377 slides with the second fitting groove portion 337. Since the rail fitting portion 377f is provided, the sliding resistance of the paper feeding cassette 9C with respect to the main body of the paper feeding device 50 is reduced, and the first direction perpendicular to the pulling-out direction and the pulling-in direction of the paper feeding cassette 9C is the first. The movement of the paper feed cassette 9C in the thrust direction of the fitting wheel 323 and the second fitting wheel 333 can be restricted.

  Therefore, not only the sliding resistance of the paper feeding cassette 9C with respect to the main body of the paper feeding device 50 is reduced, but also the movement of the paper feeding cassette 9C in the thrust direction of the first fitting wheel 323 and the second fitting wheel 333 is restricted. When this is intended, there is no need to newly provide a member for the restriction, so that the retractor 301 can be manufactured at low cost.

  Further, in the retracting device 301 according to the present embodiment, the relationship shown in the equation (2) is established between the gap A in the first fitting groove 327 and the diameter r of the engagement protrusion 344. Even if the paper cassette 9C moves by an amount corresponding to the gap A in the direction perpendicular to the drawing direction and the drawing direction of the paper feeding cassette 9C and in the thrust direction of the first fitting wheel 323 and the second fitting wheel 333, The center position of the engaging protrusion 344 can be maintained between the guide surface 342a and the guide surface 342b. Therefore, the radius (r / 2) of the engagement protrusion 344 is smaller than the gap A, and the center position of the engagement protrusion 344 cannot be maintained between the guide surface 342a and the guide surface 342b. Thus, the collision load between the inclined surfaces 342c and 342d and the engaging projection 344 can be reduced, so that the operating force of the pull-in device 301 can be reduced and the operability of the paper feed cassette 9C can be further improved. it can.

  Further, in the retracting device 301 according to the present embodiment, the guide rail fitting plate 315 is engaged with the first fitting wheel 323 in the entire stroke α, and the slide rail fitting plate 377 is engaged in the entire stroke α. Since it engages with the second fitting wheel 333, the sliding resistance between the sheet feeding cassette 9C and the body of the sheet feeding device 50 can be reduced over the entire stroke α. Further, when the paper cassette 9C is retracted, the first fitting wheel 323 and the second fitting wheel 333 are moved in the thrust direction of the first fitting wheel 323 and the second fitting wheel 333 throughout the stroke α. Since the movement of the paper feed cassette 9C can be restricted and the posture of the paper feed cassette 9C can be stabilized, the collision load between the inclined surfaces 342c and 342d and the engaging protrusion 344 can be reduced.

  Therefore, the operating force of the drawing device 301 can be reduced over the entire stroke α, and the operability of the paper feed cassette 9C can be further improved.

  Further, in the retracting device 301 according to the present embodiment, the first fitting wheel 323 and the second fitting wheel 333 are formed of resin, and the guide rail fitting plate 315 and the slide rail fitting plate 377 are formed of sheet metal. Therefore, the dimensions of the guide rail fitting plate 315 and the slide rail fitting plate 377 can be reduced as compared with the case where the guide rail fitting plate 315 and the slide rail fitting plate 377 are made of resin. That is, in the case where the guide rail fitting plate 315 and the slide rail fitting plate 377 are formed of resin, in order to ensure the strength to withstand the load applied when the paper feed cassette 9C is pulled out and pulled in, it is used for the guide rail. While it is necessary to increase the size of the fitting plate 315 and the slide rail fitting plate 377, when the guide rail fitting plate 315 and the slide rail fitting plate 377 are formed of sheet metal, they are more than the case of resin. With a small size, it is possible to ensure the strength to withstand the load applied when the paper feed cassette 9C is pulled out and pulled in.

  Therefore, the space required for the arrangement of the guide rail fitting plate 315 and the slide rail fitting plate 377 can be reduced as compared with the case where the guide rail fitting plate 315 and the slide rail fitting plate 377 are made of resin. Therefore, the retracting device 301 can be configured in a compact manner.

  In addition, since the pull-in device 301 according to the present embodiment can reduce the sliding resistance between the paper feed cassette 9C and the main body of the paper feed device 50, the first spring 348 necessary for pulling in the paper feed cassette 9C. In addition, the urging force of the second spring 349 can be reduced. Thereby, since the spring constants of the first spring 348 and the second spring 349 can be reduced, the retracting unit 340 can be configured compactly by reducing the dimensions of the first spring 348 and the second spring 349. Furthermore, since the spring constants of the first spring 348 and the second spring 349 can be reduced, the operating force of the drawing device 301 can be reduced and the operability of the paper feed cassette 9C can be improved.

  Furthermore, since the printer 500 according to the present embodiment includes the pull-in device 301 described above, the operability when the paper feed cassette 9C is pulled out and pulled in the printer 500 can be improved, and the printer 500 The appliance can be improved.

  In the present embodiment, the case where the pulling device 301 according to the present invention is applied to pulling in the paper feed cassette 9C has been described. The drawing device 301 according to the present invention may be applied as a drawing device for a process cartridge unitized by supporting members integrally. Further, when the toner bottles 40Y to 40Bk (see FIG. 1) are configured to be drawable from the printer 500, the pulling device 301 according to the present invention may be applied as the pulling device for the toner bottles 40Y to 40Bk. Good.

  Further, the first fitting wheel 323, the second fitting wheel 333, the first sliding wheel 382, the second sliding wheel 385, and the third sliding wheel 388 according to the present embodiment have polyacetal as a main component. Although described as being constituted by a resin, the resin is not limited to this, and the resin may be polyamide (PA), polycarbonate (PC), polyphenyl ether (PPE), polybutylene terephthalate (PBT), or ultrahigh molecular weight polyethylene (UHPE). Engineering plastics such as) can be used. Further, different resins may be used for each wheel depending on the use environment of each wheel, and a plurality of materials may be used for one wheel.

  Furthermore, in the present embodiment, as shown in FIG. 4C, a roller support portion 311s is formed on the end portion on the drawer side of the paper feed cassette 9C on the side plate 311 for the guide rail, and the slide rail side In the face plate 371, the roller support portion 371 s is formed at the end of the paper feed cassette 9 </ b> C on the pull-in side. A portion 311s may be formed, and a roller support portion 371s may be formed at the end of the slide rail side plate 371 on the drawer side of the paper feed cassette 9C. Also in this case, the same effect as the effect of the present invention described above can be obtained.

  As described above, the pull-in device and the image forming apparatus according to the present invention have an effect that the operability of the paper feed cassette can be improved, and include the pull-in means for pulling the paper feed cassette into the main body device. The present invention is useful as a pull-in device and an image forming apparatus including the pull-in device.

9C Paper cassette (unit)
50 Paper feeder (Main unit)
301 Pull-in device 310 Guide rail 311 Guide rail side plate (main unit)
311s roller support part (end part on the drawer side of the unit in the main unit)
314 Top plate for guide rail (main unit)
315 Guide rail fitting plate (guide member)
315f Guide rail fitting part (fitting part)
317 Guide rail bottom plate (main unit)
320 First fitting roller 323 First fitting wheel (rotating body)
324a First cylinder side fitting surface (fitting surface)
325a First truncated cone side fitting surface (fitting surface)
327 First fitting groove (groove)
330 Second fitting roller 333 Second fitting wheel (rotating body)
334a Second cylinder side fitting surface (fitting surface)
335a Second truncated cone side fitting surface (fitting surface)
337 Second fitting groove (groove)
340 Pull-in unit 341 Guide plate (engagement member, engaged member)
344 Engaging protrusion (engaged member, engaging member)
370 Slide rail 371 Slide rail side plate (unit)
371s roller support (end of unit on the drawing side)
375 Top plate for slide rail (unit)
376 Bottom plate for slide rail (unit)
377 Slide rail fitting plate (guide member)
377f Slide rail fitting part (fitting part)
380 First sliding roller (unit)
383 Second sliding roller (unit)
391 Guide rail side first stopper (limitation member)
392 Guide rail side second stopper (limitation member)
393 Slide rail side upper stopper (restriction member)

JP 2006-151687 A Japanese Patent Laid-Open No. 2007-70068

Claims (7)

A guide rail fixed to the main unit,
And relatively slidable slide rail relative to the guide rail, and a relatively slidable sheet cassette with respect to the slide rail, a drawer and retractable units to the main device,
An engagement member provided in any one of the main unit and the paper feed cassette;
An engaged member that is provided on either the main body device or the paper feed cassette and is engageable with the engaging member;
The engaging member and the engaged member are included, and when the unit is pulled and the engaging member and the engaged member are engaged, the unit is pulled to the pull-in completion position of the main body device. A retraction unit fixed to the main body device ,
The unit is rotatably attached to either the guide rail or the slide rail on the end of the unit on the pull-in side, and the other of the guide rail or the slide rail on the end of the unit on the pull-out side. Rotating body,
The guide rail and the slide rail are provided on the opposite side of the rotating bodies, engage the rotating bodies to guide the unit in the pull-out direction and the pull-in direction, and move the rotating body in the thrust direction. A guide member for restricting the movement of the rotating body,
In the engaging member and the engaged member, either the engaging member or the engaged member is constituted by a columnar member, and either the engaging member or the engaged member is A guide groove extending along the slide direction of the paper feed cassette is formed, and when the guide member engages with the rotating body to guide the unit, the columnar member extends along the guide groove. A pulling device that restricts movement of the sheet feeding cassette in a direction perpendicular to a guiding direction of the unit and in a thrust direction of the rotating body by being guided . The rotating body has a groove formed in a circumferential direction on a circumferential surface of the rotating body;
The retracting device according to claim 1, wherein the guide member has a fitting portion that fits into the groove portion. The rotating body and the guide member arranged at the end of the unit on the drawing-in side are a slide rail in a direction perpendicular to the guiding direction of the unit and in a thrust direction of the rotating body above the sheet feeding cassette. The groove portion and the fitting portion are fitted so as to restrict the movement of
The rotating body and the guide member arranged at the end portion on the drawer side of the unit are the slide rail in a direction perpendicular to the guiding direction of the unit and in a thrust direction of the rotating body below the sheet feeding cassette. The retracting device according to claim 2, wherein the groove portion and the fitting portion are fitted so as to restrict movement thereof. The groove part has a fitting surface formed in the circumferential direction facing each other;
When the diameter of the cylindrical member is r, and the gap between the fitting surface and the fitting portion is A,
r / 2> A
Retraction device according to claim 2 or claim 3, characterized in that but formed with said cylindrical member so as to establish the groove and the fitting portion. The main body device and the unit each have a limiting member that restricts drawing and drawing of the unit by a predetermined drawing width,
The said guide member is provided in the inside of the said main body apparatus so that it may engage with the said rotary body in the whole area of the said drawer | drawing-out width | variety restrict | limited by the said limitation member. The retracting device according to claim 1. The rotating body is formed of resin;
The retracting device according to any one of claims 2 to 4 , wherein the fitting portion is formed of a sheet metal.   An image forming apparatus comprising the pull-in device according to claim 1.

Images