Driving force transmission mechanism and image forming apparatus

Abstract

To provide a driving force transmission mechanism which can surely transmit driving force even when there is a manufacturing error.SOLUTION: A driving force transmission mechanism (extrusion mechanism) includes a driving force transmission device 100. The driving force transmission device includes a driving side rotary member (drive gear 82) and a driven side rotary member (ejection cam 86) both of which are attached to a support shaft 98, and a coil spring 84. The coil spring is press-fitted to a first cylindrical part 82b of the driving side rotary member and a second cylindrical part 86b of the driven side rotary member and transmits the rotational force to the driven side rotary member when the driving side rotary member is rotated in a first direction. A motor control unit (CPU) gradually increases the rotational speed of the driving side rotary member when the driving force is transmitted to a driven member (ejection arm).SELECTED DRAWING: Figure 9

Description

[Technical Field]

[0001] The present invention relates to a drive force transmission mechanism and an image forming apparatus, and more particularly to a drive force transmission mechanism including a drive force transmission device that transmits drive force from a motor to a driven member, and an image forming apparatus including the same. [Background technology]

[0002] An example of a conventional image forming apparatus equipped with this type of drive force transmission mechanism is disclosed in Patent Document 1. The image forming apparatus of Patent Document 1 includes a cartridge storage unit installed in the apparatus body, a toner cartridge configured to be insertable and removable into the cartridge storage unit, and a drive unit (drive force transmission mechanism) installed in the apparatus body and configured to be attachable and detachable to the toner cartridge. This drive unit includes a motor, a drive transmission member (drive-side rotating member), an eject cam (driven-side rotating member), an eject arm (driven member), an arm position detection sensor (displacement detection sensor), etc. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2016-109712 Summary of the Invention [Problem to be solved by the invention]

[0004] In the technology of Patent Document 1, a one-way clutch is connected to the shaft of the eject cam, and when the drive transmission member rotates in a predetermined direction, the rotational force is transmitted to the eject cam. Patent Document 1 does not disclose the specific configuration of the one-way clutch, but a drive force transmission device with one-way clutch functionality that can be made compact is desirable. It is also desirable to be able to reliably transmit drive force even if there are manufacturing errors in the components.

[0005] Therefore, a primary object of this disclosure is to provide a novel drive force transmission mechanism and image forming apparatus.

[0006] Another object of the present disclosure is to provide a driving force transmission mechanism and an image forming apparatus that can be miniaturized and can reliably transmit driving force even if there are manufacturing errors. [Means for solving the problem]

[0007] The first disclosure is a driving force transmission mechanism including a driving force transmission device that transmits driving force from a motor to a driven member, the driving force transmission device including a support shaft, a driving side rotating member having a first cylindrical portion through which the support shaft is inserted and rotatably attached to the support shaft, a driven side rotating member having a second cylindrical portion through which the support shaft is inserted and being adjacent to the driving side rotating member and rotatably attached to the support shaft, and transmitting driving force to the driven member, and a coil spring having the first cylindrical portion pressed into one end side and the second cylindrical portion pressed into the other end side, transmitting the driving force of the driving side rotating member to the driven side rotating member when the driving side rotating member is rotated in a first direction, the driving force transmission mechanism including a motor that rotates the driving side rotating member, and a motor control unit that controls the operation of the motor, and the motor control unit controls the motor to gradually increase the rotational speed of the driving side rotating member when transmitting driving force from the driven side rotating member to the driven member.

[0008] According to the first disclosure, the use of a coil spring one-way clutch allows the drive force transmission device and drive force transmission mechanism to be miniaturized. Also, the rotation speed of the drive-side rotating member is increased in stages, so drive force can be transmitted reliably even if there are manufacturing errors in the components.

[0009] The second disclosure is dependent on the first disclosure and includes a displacement detection sensor for detecting the displacement of the driven member, and the motor control unit controls the motor to increase the rotation speed of the driving side rotating member when the displacement of the driven member is not detected by the displacement detection sensor and the set value of the rotation speed of the driving side rotating member has not reached a predetermined value.

[0010] The third disclosure is dependent on the second disclosure, and the motor control unit stops the motor when the displacement detection sensor does not detect the displacement of the driven member and the set value of the rotation speed of the driving side rotating member reaches a predetermined value.

[0011] A fourth disclosure is according to the second or third disclosure, and includes a displacement detection sensor for detecting the displacement of the driven member, and a motor control unit stops the motor when the displacement detection sensor detects the displacement of the driven member.

[0012] The fifth disclosure is dependent on the first or second disclosure, and when a torque equal to or greater than a predetermined value is applied to the driven-side rotating member while the driving-side rotating member is rotated in a first direction, the first cylindrical portion or the second cylindrical portion rotates freely relative to the coil spring.

[0013] A sixth disclosure is dependent on the first or second disclosure, and the first direction in which the drive-side rotation member rotates during drive transmission is a direction in which the coil spring contracts in diameter.

[0014] The seventh disclosure is an image forming apparatus that forms an image on paper using consumables, and includes a consumables container storage unit provided in the apparatus main body, a consumables container that is removably stored in the consumables container storage unit, and an extrusion mechanism that is provided in the apparatus main body and pushes out the consumables container stored in the consumables container storage unit to a position where the consumables container can be removed, the extrusion mechanism including a support shaft, a driving-side rotating member that has a first cylindrical portion through which the support shaft is inserted and is rotatably attached to the support shaft, a driven-side rotating member that has a second cylindrical portion through which the support shaft is inserted and is rotatably attached to the support shaft adjacent to the driving-side rotating member, and a second cylindrical portion through which the support shaft is inserted, and a second cylindrical portion through which the support shaft is inserted, and a driving-side rotating member that has a second cylindrical portion through which the support shaft is inserted and is rotatably attached to the support shaft adjacent to the driving-side rotating member, and a driving-side rotating member that has a second cylindrical portion through which the support shaft is inserted, and is rotatably attached to the support shaft. The image forming device includes a coil spring into which a first cylindrical portion is pressed and a second cylindrical portion is pressed into the other end, which transmits the driving force of the driving side rotating member to the driven side rotating member when the driving side rotating member is rotated in a first direction, an arm member that displaces with the rotation of the driven side rotating member to push out a consumable container, a motor that rotates the driving side rotating member, and a motor control unit that controls the operation of the motor, wherein the motor control unit controls the motor to gradually increase the rotational speed of the driving side rotating member when the driving force is transmitted from the driven side rotating member to the arm member to push out the consumable container.

[0015] According to the seventh disclosure, the use of a coil spring one-way clutch allows the ejection mechanism to be made smaller. Also, the rotation speed of the drive-side rotating member is increased in stages, so the ejection operation can be performed reliably even if there are manufacturing errors in the components.

[0016] An eighth disclosure is according to the seventh disclosure, and includes an arm position detection sensor for detecting displacement of the arm member, and a motor control unit controls the motor to increase the rotation speed of the driving side rotating member when the arm position detection sensor does not detect displacement of the arm member and the set value of the rotation speed of the driving side rotating member has not reached a predetermined value. [Effects of the Invention]

[0017] According to this disclosure, the use of a coil spring one-way clutch allows for a more compact device, and the rotational speed of the drive-side rotating member is increased in stages, ensuring reliable transmission of driving force even when there are manufacturing errors in the components.

[0018] The above and other objects, features, and advantages of the present disclosure will become more apparent from the following detailed description of the embodiments, which proceeds with reference to the drawings. [Brief explanation of the drawings]

[0019] [Figure 1] FIG. 2 is a schematic cross-sectional view showing the internal structure of the image forming apparatus. [Figure 2] FIG. 2 is a diagram showing a state in which a toner cartridge is housed in a toner cartridge housing portion. [Figure 3] FIG. 2 is a perspective view showing a toner cartridge and a drive unit. [Figure 4] FIG. 2 is a perspective view showing a drive unit in a reference state. [Figure 5] FIG. 10 is a diagram showing the extrusion mechanism in a reference state as viewed from above. [Figure 6] 10 is a diagram showing an eject cam and an eject lever in a reference state as viewed from the front. FIG. [Figure 7] 10A and 10B are diagrams illustrating a driving force transmission device included in the extrusion mechanism. [Figure 8] FIG. 2 is an exploded perspective view showing the driving force transmission device. [Figure 9] FIG. 2 is a cross-sectional view showing a driving force transmission device. [Figure 10] FIG. 10 is a diagram showing the ejection mechanism in the ejecting state as viewed from above. [Figure 11] FIG. 10 is an illustrative view showing an eject cam and an eject lever in an ejected state as viewed from the front; [Figure 12] FIG. 10 is an illustrative view showing a state in which the toner cartridge is in a removable position. [Figure 13] FIG. 2 is a block diagram showing an example of an electrical configuration of the image forming apparatus. [Figure 14] FIG. 2 is a diagram illustrating an example of a memory map of a RAM. [Figure 15] FIG. 10 is a flowchart illustrating an example of an extrusion process of a CPU. DETAILED DESCRIPTION OF THE INVENTION

[0020] [Example] 1, an image forming apparatus 10 according to an embodiment of the present disclosure is a color printer that forms a multicolor or monochrome image on paper (recording medium) by electrophotography. As will be described in detail later, the image forming apparatus 10 includes a push-out mechanism 80 (an example of a drive force transmission mechanism) that pushes out the toner cartridge 32 housed in the cartridge housing unit 52 from a housing position to a removable position. The push-out mechanism 80 includes a drive force transmission device 100 that transmits drive force from the motor 72 to an eject arm 90.

[0021] In this specification, when describing directions, the front side when viewing image forming apparatus 10 from the front will be referred to as the "front side," the back side will be referred to as the "rear side," the left side will be referred to as the "left side," the right side will be referred to as the "right side," the top side will be referred to as the "upper side," and the bottom side will be referred to as the "lower side." Furthermore, when describing toner cartridge 32, the directions will be those when toner cartridge 32 is housed in cartridge housing 52.

[0022] First, a basic configuration of an image forming apparatus 10 will be described briefly. As shown in FIG. 1, the image forming apparatus 10 includes components such as a photosensitive drum 12, a developing device 14, a charger 16, a cleaning unit 18, an exposure device 20, an intermediate transfer belt unit 22, a secondary transfer roller 24, and a fixing unit 26. The image forming apparatus 10 forms an image on paper conveyed from a paper feed tray 28 and discharges the paper with the image formed onto a paper discharge tray 30. Image data input from an external computer is used as image data for forming an image on the paper. However, if the image forming apparatus 10 has a scanner function, it can use not only image data input from an external device but also image data read from an original document by the scanner.

[0023] The above-mentioned components are housed in the device body 10a of the image forming apparatus 10. A control unit including a CPU 150, a RAM 154, an HDD 156, etc. (see FIG. 13) is also provided in the device body 10a of the image forming apparatus 10. The control unit transmits control signals to each part of the image forming apparatus 10, causing the image forming apparatus 10 to perform various operations. Therefore, this control unit also serves as a control unit for the extrusion mechanism 80, which is an example of a drive force transmission mechanism. Although not shown, the device body 10a is also provided with an operation panel that accepts operations from the user. The operation panel is appropriately provided with a display with a touch panel (touch panel display), a plurality of operation buttons, etc.

[0024] Here, the image data handled by the image forming apparatus 10 corresponds to a color image consisting of four colors: black (BK), magenta (M), cyan (C), and yellow (Y). For this reason, four photosensitive drums 12, developing devices 14, chargers 16, and cleaning units 18 are provided so as to form four types of latent images corresponding to each color, and these constitute four image stations.

[0025] The photoreceptor drum 12 is an image carrier with a photosensitive layer formed on the surface of a conductive substrate, and is rotatable about its axis by a drive unit (not shown). The charger 16 charges the surface of the photoreceptor drum 12 to a predetermined polarity and potential. The cleaning unit 18 removes and collects toner remaining on the surface of the photoreceptor drum 12 after a toner image is transferred from the photoreceptor drum 12 to the intermediate transfer belt 36. The exposure device 20 is configured as a laser scanning unit (LSU) equipped with a laser emitter, a reflecting mirror, etc., and exposes the charged surface of the photoreceptor drum 12 to light to form an electrostatic latent image on the surface of the photoreceptor drum 12 according to image data.

[0026] The developing device 14 visualizes the electrostatic latent image formed on the surface of the photosensitive drum 12 using toner, which is an example of a consumable item (forming a toner image). A toner cartridge 32, which is an example of a consumable item container described below, is connected to the developing device 14 via a toner supply pipe 34. The toner cartridge 32 is a container that stores unused toner and carrier (hereinafter, toner and carrier may be collectively referred to simply as "toner"), and is stored in a cartridge storage section 52 (see FIG. 2) provided above the developing device 14, and supplies toner to the developing device 14.

[0027] The intermediate transfer belt unit 22 includes an intermediate transfer belt 36, a drive roller 38, a driven roller 40, four intermediate transfer rollers 42, and the like.

[0028] The intermediate transfer belt 36 is a flexible, endless belt that is stretched around multiple rollers, including a drive roller 38 and a driven roller 40, and is disposed so that its surface (outer periphery) contacts the surface of the photosensitive drum 12. The intermediate transfer belt 36 rotates (circularly moves) in a predetermined direction as the drive roller 38 is driven to rotate. The drive roller 38 is rotatable about its axis by a drive unit (not shown). The driven roller 40 rotates as the intermediate transfer belt 36 moves circularly, and applies a constant tension to the intermediate transfer belt 36 to prevent slack in the intermediate transfer belt 36.

[0029] The intermediate transfer rollers 42 are disposed at positions facing each photosensitive drum 12 across the intermediate transfer belt 36, and are pressed against the inner circumferential surface of the intermediate transfer belt 36, rotating as the intermediate transfer belt 36 rotates. During image formation, a voltage of opposite polarity to the charge polarity of the toner that constitutes the toner image formed on the surface of the photosensitive drum 12 is applied to the intermediate transfer rollers 42. The toner image formed on the photosensitive drum 12 is transferred to the outer circumferential surface of the intermediate transfer belt 36 by the action of a transfer electric field formed thereby.

[0030] Furthermore, a secondary transfer roller 24 is disposed at a position facing the drive roller 38 across the intermediate transfer belt 36. During image formation, a voltage (secondary transfer voltage) is applied to the secondary transfer roller 24, and the toner image formed on the outer peripheral surface of the intermediate transfer belt 36 is transferred (secondarily transferred) to the paper by the action of a transfer electric field formed thereby while the paper passes through a transfer nip area between the intermediate transfer belt 36 and the secondary transfer roller 24. Thereafter, the toner remaining on the surface of the intermediate transfer belt 36 is removed and collected by a transfer belt cleaning unit (not shown).

[0031] The fixing unit 26 includes a heat roller, a pressure roller, etc., and is disposed above the secondary transfer roller 24. The heat roller is set to a predetermined fixing temperature, and when paper passes through the fixing nip area between the heat roller and the pressure roller, the toner image transferred to the paper is melted, mixed, and pressed against the paper, thereby thermally fixing the toner image to the paper.

[0032] Furthermore, a paper transport path L is formed within the device body 10a of the image forming apparatus 10 for sending paper placed in the paper feed tray 28 to the paper output tray 30 via the secondary transfer roller 24 and the fixing unit 26. Paper transport means such as a plurality of transport rollers 44 and registration rollers 46 are appropriately arranged along this paper transport path L. During image formation, paper placed in the paper feed tray 28 is guided one sheet at a time to the paper transport path L by a pickup roller (not shown), and is transported to the registration rollers 46 by the transport rollers 44. The registration rollers 46 then transport the paper to the secondary transfer rollers 24 when the leading edge of the paper aligns with the leading edge of the toner image on the intermediate transfer belt 36, and the toner image is transferred onto the paper. Thereafter, the paper passes through the fixing unit 26, whereby unfixed toner on the paper is melted and fixed by heat, and the paper is output onto the paper output tray 30.

[0033] Next, a description will be given of the toner cartridges 32 and the cartridge storage unit 52. Note that Figure 2 shows a state in which all of the toner cartridges 32 are stored in the cartridge storage unit 52.

[0034] As shown in Fig. 2, the apparatus main body 10a is provided with four cartridge storage units 52, which are an example of consumable container storage units. A corresponding toner cartridge 32 is removably stored (attached) in each of the four cartridge storage units 52. For example, an attachment / detachment opening 52a for the cartridge storage unit 52 is provided on the front side of the image forming apparatus 10, and the toner cartridge 32 is pushed into the cartridge storage unit 52 from the attachment / detachment opening 52a toward the rear. The toner cartridge 32 is removed by pulling it out of the cartridge storage unit 52 toward the front.

[0035] The device main body 10a also has a front door 10b that is openable and closable on its front side. When the front door 10b is closed, it covers the four cartridge storage compartments 52. When the front door 10b is open, the front covers 62 of the toner cartridges 32 stored in the cartridge storage compartments 52 are exposed.

[0036] When the toner cartridge 32 is in the storage position, the position of the front surface of the front cover 62 is either at the same position as the attachment / detachment opening 52a of the cartridge storage unit 52 in the front-to-rear direction or slightly behind the attachment / detachment opening 52a of the cartridge storage unit 52. Therefore, when the toner cartridge 32 is in the storage position, the user cannot grasp the toner cartridge 32 and cannot or cannot easily remove the toner cartridge 32 from the cartridge storage unit 52.

[0037] 3 shows the toner cartridge 32 connected to the drive unit 70 provided in the device main body 10a. The drive unit 70 is provided at the back (rear) of the cartridge storage section 52, and the toner cartridge 32 and the drive unit 70 are connected when the toner cartridge 32 is stored in the cartridge storage section 52 (moved to the storage position).

[0038] As shown in FIG. 3, the toner cartridge 32 includes a container body 60, a front cover 62, and a cartridge-side connector 64. The container body 60 is a rectangular cylindrical container that is long in the front-to-rear direction and contains toner. Although not shown, a toner discharge mechanism is provided inside the container body 60, and a toner discharge port is formed at the rear end of the container body 60. The toner discharge mechanism includes an auger screw that transports toner toward the toner discharge port, and an agitator that agitates the toner in the container body 60 to loosen it and supplies toner to the auger screw. The container body 60 may have other shapes, such as a cylindrical shape.

[0039] The front cover 62 is detachably provided at the front end of the toner cartridge 32. This front cover 62 functions as a lid that closes the front opening of the container body 60. In addition, the front end of the toner cartridge 32, including the front cover 62, functions as a grip that the user can grip when removing the toner cartridge 32 from the cartridge storage section 52.

[0040] Furthermore, a cartridge-side connector 64 (hereinafter simply referred to as "connector 64") is provided at the rear end of the container body 60. Although not shown, the connector 64 is provided with terminals that are electrically connected to a CRUM chip 68 (see FIG. 13) provided in the toner cartridge 32. For example, the CRUM chip 68 is provided inside the socket of the connector 64. This CRUM chip 68 stores model information indicating the model of the image forming apparatus 10 to which the toner cartridge 32 is applied, identification information for the toner cartridge 32, information for managing toner replenishment, and the like.

[0041] When the toner cartridge 32 is stored in the cartridge storage section 52, the connector 64 is connected to a main body connector (not shown) provided in the cartridge storage section 52. The main body connector is provided with a terminal electrically connected to a communication section 158 (see FIG. 13) of the device main body 10a, and by connecting the connector 64 to the main body connector, the CRUM chip 68 and the communication section 158 (and therefore the CPU 150) are electrically connected and become able to communicate.

[0042] Furthermore, when the toner cartridge 32 is in the storage position, the toner discharge port formed in the container body 60 is connected to the toner supply pipe 34, and the toner discharged from the toner discharge port is supplied to the developing device 14 via the toner supply pipe 34. In other words, the toner cartridge 32 is ready for use. Note that the storage position refers to the rearmost position of the toner cartridge 32 when inserted into the cartridge storage section 52, and is the position at which the toner cartridge 32 cannot be moved any further rearward.

[0043] 4 together with FIG. 3, the drive unit 70 includes a motor 72, a drive transmission member 74, a drive transmission member 76, and a push-out mechanism 80. However, in FIG. 4, part of the upper cover of the drive unit 70 is omitted.

[0044] The motor 72 is a general-purpose motor such as a stepping motor, and is capable of switching between forward and reverse rotation. The direction and number of rotations (pulse rate) of the motor 72 are switched by instructions from the control unit (CPU 150) of the image forming apparatus 10.

[0045] The drive transmission member 74 and the drive transmission member 76 are each a member for transmitting the rotational drive force of the motor 72, which is the drive source, to an auger screw or an agitator member provided inside the toner cartridge 32. The drive transmission member 74 and the drive transmission member 76 are provided forward of the motor 72. The rotational axes of the drive transmission member 74 and the drive transmission member 76 are in the front-to-rear direction.

[0046] When the toner cartridge 32 and the drive unit 70 are connected, the drive transmission member 74 is connected to the auger screw of the toner cartridge 32. Furthermore, when the toner cartridge 32 and the drive unit 70 are connected, the drive transmission member 76 is connected to the agitator of the toner cartridge 32. Therefore, the auger screw is rotated by the rotational drive force transmitted from the drive transmission member 74, and the agitator is rotated by the rotational drive force transmitted from the drive transmission member 76.

[0047] A rotational drive force is transmitted to drive transmission members 74 and 76 regardless of the rotation direction of motor 72. However, the auger screw transports toner toward the rear when motor 72 is rotated forward. In other words, when the toner is discharged, motor 72 is rotated forward. As a result, the toner in container body 60 is transported toward the rear while being agitated by the auger screw and the agitator, and is supplied to developing device 14 through a toner discharge port formed at the rear end of container body 60 and via toner supply pipe 34.

[0048] On the other hand, when motor 72 rotates in the reverse direction, push-out mechanism 80 is activated, and push-out mechanism 80 performs an operation to push out (eject) toner cartridge 32. In other words, motor 72 serves both as a motor that drives push-out mechanism 80 and a motor that drives a toner discharge mechanism of toner cartridge 32. The rotation direction of motor 72 when push-out mechanism 80 pushes out toner cartridge 32 is set to be opposite to the rotation direction of motor 72 when toner discharge mechanism discharges toner from toner cartridge 32.

[0049] An example of the configuration of the extrusion mechanism 80 will be specifically described below with reference to Figures 4 to 6. Note that Figures 4 to 6 show the extrusion mechanism 80 in a standard state.

[0050] 4 to 6, the push-out mechanism 80 is a mechanism for pushing out the toner cartridge 32 housed in the cartridge housing portion 52 from the housing position to the removal position using the driving force of the motor 72. The push-out mechanism 80 is equipped with a drive transmission device 100 including a drive gear 82, a coil spring 84, an eject cam 86, etc., as well as an eject lever 88, an eject arm 90, a shaft support member 92, a biasing member 94, an arm position detection sensor 96, etc.

[0051] 4 to 6, the eject lever 88 and the eject arm 90 are shaded for ease of understanding. The same applies to Figures 10 and 11. Although it is difficult to see in Figure 4, the eject arm 90 is disposed below the coupling gear of the drive transmission member 76.

[0052] The drive transmission device 100 is a device that transmits the drive force from the motor 72 to the eject arm 90 via the eject lever 88, and includes a drive gear 82, a coil spring 84, an eject cam 86, etc. The drive gear 82 is located forward of the motor 72, and its rotational axis is in the front-to-rear direction. When the motor 72 rotates forward, the drive gear 82 rotates clockwise as viewed from the front, and when the motor 72 rotates reverse, the drive gear 82 rotates counterclockwise as viewed from the front. Furthermore, the rotational axes of the coil spring 84 and the eject cam 86 also extend in the front-to-rear direction, and the drive gear 82, the coil spring 84, and the eject cam 86 are arranged coaxially.

[0053] As will be described later, this driving force transmission device 100 has a one-way clutch function, and when the drive gear 82 rotates in a first direction (counterclockwise in this embodiment), the rotational force is transmitted to the eject cam 86. In other words, when the motor 72 rotates forward, the rotational driving force is not transmitted to the eject cam 86, and the rotational driving force is transmitted to the eject cam 86 only when the motor 72 rotates reversely. This driving force transmission device 100 also has a torque limiter function. The specific configuration of the driving force transmission device 100 will be described later.

[0054] The eject lever 88 is disposed between the eject cam 86 and the eject arm 90. The eject lever 88 has a shaft 88a, an arm 88b, and a gear 88c. The shaft 88a is cylindrical and rotatably supported by a shaft 92a extending vertically on the shaft support member 92. Therefore, the eject lever 88 can rotate horizontally around the shaft 92a. The arm 88b is L-shaped and extends rearward from the shaft 88a. The arm 88b is biased toward the eject cam 86 by one end 94a of a biasing member (torsion spring) 94 attached to the outer peripheral surface of the shaft 88a, and abuts against the left outer surface of the eject cam 86. Therefore, the eject lever 88 rotates so that the arm 88b moves left and right as the eject cam 86 rotates, i.e., depending on the rotational position of the eject cam 86. The gear 88c is formed in an arc shape and projects forward from the shaft portion 88a. The gear 88c is an externally toothed gear and meshes with a gear 90d of the eject arm 90, which will be described later. However, the tooth shapes of the gears 88c and 90d are omitted in Figures 4 and 5 (as well as Figure 10).

[0055] The eject arm 90 (an example of a driven member) is an arm member disposed in front of the eject lever 88. The eject arm 90 has a shaft portion 90a, an arm portion 90b, a contact portion 90c, a gear 90d, and a protrusion 90e. The shaft portion 90a is cylindrical and is rotatably supported by a shaft 92b extending vertically of the shaft support member 92. Therefore, the eject arm 90 is rotatable horizontally around the shaft 92b, and the rotation axis of the eject arm 90 is parallel to the rotation axis of the eject lever 88. The arm portion 90b extends rightward from the shaft portion 90a, and a contact portion 90c protruding forward is formed at the right end (tip) of the arm portion 90b. The contact portion 90c is the portion that comes into contact with the rear end of the toner cartridge 32 during the ejection operation. The gear 90d is formed in an arc shape and projects rearward from the shaft portion 90a. This gear 90d is an externally toothed gear and meshes with the gear 88c of the eject lever 88. Therefore, the eject arm 90 rotates such that the contact portion 90c moves forward and backward as the eject lever 88 rotates. The biasing force of the biasing member 94 acts on the eject arm 90 in a direction that moves the contact portion 90c away from the toner cartridge 32. Furthermore, a protrusion 90e is formed on the front surface of the longitudinal center of the eject arm 90 so as to protrude forward.

[0056] The axial support member 92 includes a shaft 92a, a shaft 92b, a base 92c, and a support post 92d. Although not shown in the drawings, the axial support member 92 is fixed to the device main body 10a. The base 92c is a flat plate-shaped member, and in addition to the above-mentioned shafts 92a and 92b, a support post 92d is provided on the upper surface of the base 92c. The support post 92d is a rectangular pillar extending in the vertical direction, and the other end 94b of the biasing member 94 is engaged with this support post 92d.

[0057] The arm position detection sensor 96 (an example of a displacement detection sensor) is a sensor for detecting position information, i.e., displacement, of the eject arm 90, and is arranged in front of the eject arm 90. The arm position detection sensor 96 is, for example, a photosensor having a light-emitting element and a light-receiving element, and is configured so that when the eject arm 90 reaches the eject position, the protrusion 90e of the eject arm 90 blocks the light from the light-emitting element. In other words, the arm position detection sensor 96 is a sensor that can detect whether the eject arm 90 is in the eject position (i.e., whether the eject arm 90 is displaced or not).

[0058] Next, the configuration of the driving force transmission device 100 will be described in detail with reference to Figures 7 to 9. As shown in Figures 7 to 9, the driving force transmission device 100 includes a driving gear 82, which is an example of a driving-side rotating member, a coil spring 84, an eject cam 86, which is an example of a driven-side rotating member, and a support shaft 98.

[0059] The support shaft 98 is a fixed shaft made of metal and formed in a substantially cylindrical shape, and is provided so as to extend in the front-rear direction. The support shaft 98 rotatably supports the drive gear 82 and the eject cam 86.

[0060] The drive gear 82 is a member for transmitting the rotational drive force of the motor 72 to the eject cam 86, and is connected to the eject cam 86 via a coil spring 84. The drive gear 82 has an annular plate-shaped base portion 82a, a first cylindrical portion 82b (first shaft portion) protruding forward (toward the eject cam 86) from the center of the base portion 82a, and a cylindrical gear portion 82c provided on the peripheral edge of the base portion 82a so as to cover the periphery of the first cylindrical portion 82b. Although not shown, gear teeth are provided on the outer peripheral surface of the gear portion 82c. The drive gear 82 is rotatably attached to the support shaft 98 forward of the motor 72 by inserting the support shaft 98 into the first cylindrical portion 82b. When the motor 72 of the drive unit 70 rotates forward, the drive gear 82 rotates clockwise when viewed from the front, and when the motor 72 of the drive unit 70 rotates reversely, the drive gear 82 rotates counterclockwise when viewed from the front.

[0061] The eject cam 86 is a cam member disposed adjacent to the drive gear 82 on the front side of the drive gear 82. The eject cam 86 has an annular plate-shaped base 86a, a second cylindrical portion 86b (second shaft portion) protruding rearward (toward the drive gear 82) from the center of the base 86a, and a substantially cylindrical cam portion 86c formed on the periphery of the base 86a. In this embodiment, the eject cam 86 is a flat cam, and the cam portion 86c has a protrusion 86d protruding tangentially from its outer circumferential surface. The eject cam 86 is rotatably attached to the support shaft 98 by inserting the support shaft 98 into the second cylindrical portion 86b so that the first cylindrical portion 82b and the second cylindrical portion 86b face each other. The eject cam 86 is rotated by a rotational driving force transmitted from the drive gear 82 via the coil spring 84.

[0062] The coil spring 84 is a member for transmitting the rotational driving force of the drive gear 82 to the eject cam 86 when the drive gear 82 rotates in a first direction (counterclockwise in this embodiment). In this embodiment, a square spring with a rectangular cross section is used as the coil spring 84. The first cylindrical portion 82b of the drive gear 82 is press-fitted into one end of the coil spring 84, and the second cylindrical portion 86b of the eject cam 86 is press-fitted into the other end of the coil spring 84, thereby interlocking the drive gear 82 and the eject cam 86. In this case, the coil spring 84 is attached to the first cylindrical portion 82b and the second cylindrical portion 86b so that its diameter decreases when the drive gear 82 rotates in the first direction. In other words, the first direction in which the drive gear 82 rotates when transmitting drive is the direction in which the diameter of the coil spring 84 decreases, and the tip of the wire constituting the coil spring 84 on the drive gear 82 side extends in the first direction.

[0063] In the driving force transmission device 100, when the motor 72 rotates forward and the drive gear 82 rotates in the second direction (clockwise in this embodiment), if the ejection mechanism 80 is in a reference state and a torque equal to or greater than a predetermined value is applied to the eject cam 86, as described below, the coil spring 84 expands in diameter (i.e., loosens), resulting in a limiter slip state in which the first cylindrical portion 82b or the second cylindrical portion 86b rotates freely relative to the coil spring 84. As a result, the rotational driving force is not transmitted to the eject cam 86, and the eject arm 90 does not operate. On the other hand, when the motor 72 rotates reversely and the drive gear 82 rotates in the first direction, the coil spring 84 contracts in diameter (i.e., tightens), ensuring that the rotational driving force is transmitted from the drive gear 82 to the eject cam 86, thereby operating the eject arm 90. In other words, in the driving force transmission device 100, the action of the coil spring 84 provides a one-way clutch function.

[0064] Furthermore, in the driving force transmission device 100, even when the motor 72 rotates in the reverse direction and the drive gear 82 rotates in the first direction, if some malfunction occurs and a torque greater than a predetermined value is applied to the eject cam 86, the first cylindrical portion 82b or the second cylindrical portion 86b will rotate freely relative to the coil spring 84 against the frictional force with the coil spring 84. In other words, in the driving force transmission device 100, the action of the coil spring 84 also exhibits a torque limiter function.

[0065] In this way, in the driving force transmission device 100, by providing the coil spring 84 with a one-way clutch function (i.e., employing a coil spring-type one-way clutch), the one-way clutch function can be achieved with a simpler configuration than other types of one-way clutches such as ratchet and sprag types, and the device can be made more compact. Furthermore, because it also has a torque limiter function, it can be suitably employed in the extrusion mechanism 80, contributing to space savings.

[0066] Next, the pushing-out operation of the toner cartridge 32 by the pushing-out mechanism 80 will be described with reference to Figures 4-6, 10, and 11. The pushing-out operation refers to the operation of pushing out the toner cartridge 32 from the storage position to the removal position. Figures 10 and 11 show the state when the pushing-out mechanism 80 is in the eject state, that is, when the toner cartridge 32 has been pushed out to the removal position.

[0067] This extrusion operation is performed automatically by instruction from CPU 150 provided in device main body 10a when it is determined that toner cartridge 32 needs to be replaced. Circumstances where toner cartridge 32 needs to be replaced include, for example, when the toner in toner cartridge 32 falls below a predetermined amount, when a toner supply failure occurs in toner cartridge 32, or when an incorrect toner cartridge is inserted into cartridge storage section 52. Whether the toner in toner cartridge 32 has fallen below a predetermined amount (i.e., the remaining toner amount) is determined (detected) by, for example, whether the total number of rotations of the auger screw of toner cartridge 32 is equal to or greater than a threshold value, whether the total number of counted print dots is equal to or greater than a threshold value, whether no toner has fallen from toner cartridge 32, etc.

[0068] 5 and 6, when the push-out mechanism 80 is in the standard state, the eject arm 90 is located at the rearmost arm standard position. In this standard state, a small gap is formed between the contact portion 90c of the eject arm 90 and the rear end of the toner cartridge 32.

[0069] Furthermore, when the extrusion mechanism 80 is in the reference state, the eject cam 86 is located at a cam reference position where the upper surface of the protrusion 86d abuts against the lower surface of the arm 88b of the eject lever 88. Therefore, in this reference state, when the toner cartridge 32 performs a normal toner transport operation, that is, when the motor 72 rotates forward, the one-way clutch (coil spring 84) of the driving force transmission device 100 enters a limiter slip state. Therefore, even if the motor 72 rotates forward during a normal toner transport operation, the eject cam 86 does not rotate, and therefore the eject lever 88 and eject arm 90 do not move. In other words, the reference state is maintained.

[0070] When it is determined that the toner cartridge 32 needs to be replaced, the ejection operation is started from this reference state. When the ejection operation is performed, the motor 72 is rotated in reverse. When the motor 72 is rotated in reverse, a driving force is transmitted from the drive gear 82 to the eject cam 86 via the coil spring 84, causing the eject cam 86 to rotate counterclockwise as viewed from the front. However, the rotation angle of the motor 72 of the drive unit 70 during the ejection operation is basically set so that the eject cam 86 rotates once by controlling the rotation time of the motor 72.

[0071] As the eject cam 86 rotates counterclockwise from the cam reference position, the left side of the arm 88b of the eject lever 88 rides up on the protrusion 86d during one rotation. As a result, as shown in FIGS. 10 and 11 , the arm 88b of the eject lever 88 moves leftward, causing the eject lever 88 to rotate counterclockwise as viewed from above against the biasing force of the biasing member 94. This causes the eject arm 90 to rotate clockwise as viewed from above, causing the abutment portion 90c to move from the rear side to the front side. At this time, the abutment portion 90c pushes the toner cartridge 32, which is in the storage position, forward, moving the toner cartridge 32 to the removal position. In other words, when the push-out mechanism 80 enters the eject state, the toner cartridge 32 is pushed to the removal position where the front end of the toner cartridge 32 protrudes from the attachment / detachment opening 52a of the cartridge storage portion 52.

[0072] When the eject cam 86 further rotates counterclockwise from the eject state, the arm 88b of the eject lever 88 moves over the protrusion 86d of the eject cam 86 and is then moved to the right by the biasing force of the biasing member 94. Accordingly, the eject arm 90 rotates counterclockwise as viewed from above, and the contact portion 90c moves from the front side to the rear side. In other words, the eject arm 90 returns to the arm reference position, and the extrusion mechanism 80 returns to the reference state. However, because the contact portion 90c and the toner cartridge 32 are no longer connected, the toner cartridge 32 remains in the removal position.

[0073] 12, when the toner cartridge 32 is in the removable position, the front end of the toner cartridge 32 protrudes forward from the attachment / detachment opening 52a of the cartridge storage unit 52. For example, the removable position is a position where the toner cartridge 32 has moved approximately 15 to 20 mm forward from the storage position. In other words, the front end of the toner cartridge 32 protrudes approximately 15 to 20 mm forward from the attachment / detachment opening 52a of the cartridge storage unit 52. In this case, the user can grip the front end of the toner cartridge 32 and easily remove the toner cartridge 32 from the cartridge storage unit 52.

[0074] The distance by which the toner cartridge 32 is pushed forward by the push-out mechanism 80 is set shorter than the distance (gap) between the front end of the toner cartridge 32 in the storage position (the front surface of the front cover 62) and the front door 10b of the device main body 10a in the closed state. This is to prevent the front end of the toner cartridge 32 pushed forward by the ejection operation from colliding with the front door 10b of the device main body 10a.

[0075] 13 is a block diagram showing an example of the electrical configuration of the image forming apparatus 10. However, some components that are not directly related to the present invention are omitted.

[0076] 13, the image forming apparatus 10 includes a CPU 150, which is connected to a RAM 154 and an HDD 156 via a bus 152. The CPU 150, RAM 154, HDD 156, etc. form a control unit of the image forming apparatus 10. The CPU 150 is also connected to a communication unit 158, a motor 72, etc. via the bus 152. The communication unit 158 ​​is also connected to the CRUM chip 68 of the toner cartridge 32.

[0077] The CPU 150 performs overall control of the image forming apparatus 10 in accordance with a program stored in the HDD 156. The CPU 150 also functions as a control unit that executes the extrusion process of this embodiment and as a motor control unit that controls the operation of the motor 72. The RAM 154 is used as a working area and buffer area for the CPU 150. The HDD 156 stores control programs and necessary data for the CPU 150 to control the operation of each component of the image forming apparatus 10 as appropriate. However, instead of or together with the HDD 156, other non-volatile memories such as an SSD, flash memory, or EEPROM may be used.

[0078] The communication unit 158 ​​is a communication circuit for communicating with the CRUM chip 68 provided in the toner cartridge 32 , and communicates with the CRUM chip 68 in accordance with instructions from the CPU 150 .

[0079] As described above, motor 72 is a motor that drives the toner discharge mechanism of toner cartridge 32 and also drives push-out mechanism 80. Motor 72 is driven in accordance with instructions from CPU 150, and applies driving force to the toner discharge mechanism of toner cartridge 32 and push-out mechanism 80 by rotating forward or reverse.

[0080] The operation of the push-out mechanism 80 as described above is performed by controlling the rotation direction, rotation speed, and driving time (i.e., the number of rotations) of the motor 72. However, if there are manufacturing errors in the components that make up the push-out mechanism 80, it may not be possible to properly execute the pushing operation of the toner cartridge 32. In particular, when a coil spring-type one-way clutch is used, depending on manufacturing errors and environmental conditions, even if the drive gear 82 is rotated in the first direction, the coil spring 84 may not engage and slip, preventing the driving force from being transmitted to the eject cam 86.

[0081] Therefore, in this embodiment, the rotation speed (pulse rate) of the motor 72 is controlled so that the rotation speed of the drive gear 82 is increased stepwise from a low speed to a high speed, thereby ensuring reliable extrusion even when there are manufacturing errors in the components (drive gear 82, coil spring 84, eject cam 86, etc.) that make up the drive transmission device 100. This is based on the knowledge found through verification experiments by the inventors that, although it would normally seem that power transmission is easier at low speeds, in reality, components that are free from manufacturing errors will operate at low speeds (low rotation speeds), and components that are free from manufacturing errors will not operate at low speeds but will engage and operate as the speed increases (high rotation speeds). It is also possible to set the rotation speed to high from the beginning, but this would mean that although there would be no problem with manufacturing errors, the engagement force would be too strong and the toner cartridge 32 would fly out at high speed, and the upper limit of the torque limiter would increase, which could cause problems in preventing user injury and could cause parts to be worn down by friction between metals, shortening their lifespan.For these reasons, the rotation speed of the drive gear 82 is increased in stages.

[0082] Specifically, when executing the extrusion operation, first, the motor 72 is rotated in reverse for a predetermined time (the time required for one rotation of the eject cam 86) at an initial value set to a low rotation speed (for example, 300 [ppm]). At this time, if the arm position detection sensor 96 detects displacement of the eject arm 90, it is determined that the extrusion operation has been performed properly, and the motor 72 is stopped to end the extrusion operation.

[0083] On the other hand, if the arm position detection sensor 96 does not detect any displacement of the eject arm 90 even when the motor 72 is rotated in reverse (i.e., if it is not detected that the eject arm 90 is at the eject position), it is determined that the ejection operation was not performed properly. In this case, if the set value of the rotation speed of the motor 72 (i.e., the set value of the rotation speed of the drive gear 82) has not reached a predetermined value (e.g., 700 [ppm]), the rotation speed of the motor 72 is set to a high rotation speed (e.g., 700 [ppm]), and the motor 72 is rotated in reverse again for a predetermined time. On the other hand, if the set value of the rotation speed of the motor 72 has reached the predetermined value, the motor 72 is stopped, and the user is notified that an eject error has occurred by, for example, displaying a message on the display.

[0084] Fig. 14 is an illustrative view showing an example of a memory map 200 of the RAM 154. As shown in Fig. 14, the RAM 154 includes a program storage area 202 and a data storage area 204. The program storage area 202 of the RAM 154 stores an image forming program 202a, an extrusion condition determination program 202b, a communication program 202c, an extrusion control program 202d, etc.

[0085] The image forming program 202a is a program for controlling components such as the photosensitive drum 12 to print a multi-color or monochrome image on paper. The extrusion condition determination program 202b is a program for determining whether the toner cartridge 32 needs to be replaced. The communication program 202c is a program for sending and receiving necessary information to and from the CRUM chip 68 of the toner cartridge 32. The extrusion control program 202d is a program for controlling the motor 72 to cause the extrusion mechanism 80 to perform an extrusion operation. This extrusion control program 202d includes a rotation control program for controlling the rotation speed of the motor 72 so as to gradually increase the rotation speed of the drive gear 82 from low to high.

[0086] Although not shown, the program storage area 202 also stores other programs for causing the CPU 150 to execute various functions as appropriate.

[0087] Furthermore, the data storage area 204 of the RAM 154 stores an image data buffer 204a, a remaining toner amount data buffer 204b, rotation condition data 204c, and the like.

[0088] The image data buffer 204a is a buffer for temporarily storing image data etc. transmitted from an external computer. The remaining toner amount data buffer 204b is a buffer for temporarily storing the remaining toner amount in the toner cartridge 32 transmitted from the toner cartridge 32. The rotation condition data 204c is data on rotation conditions such as the rotation speed (initial value, increment, etc.) and rotation time of the motor 72 used when the extrusion mechanism 80 performs the extrusion operation.

[0089] Although not shown, the data storage area 204 is provided with a timer (counter) or register required for executing the control program, and stores other data required for executing the control program.

[0090] 15 is a flow diagram showing an example of the extrusion process (ejection process) executed by CPU 150 of image forming apparatus 10. This extrusion process is started when it is determined that toner cartridge 32 needs to be replaced, for example, when the toner in toner cartridge 32 becomes less than a predetermined amount.

[0091] 15, when the extrusion process is started, the CPU 150 sets the rotation speed N of the motor 72 to an initial value (for example, 300 [ppm]) in step S1. In the next step S3, a control signal is sent to the motor 72 to rotate the motor 72 in the reverse direction at the set rotation speed N.

[0092] In the next step S5, it is determined whether a predetermined time has elapsed. That is, it is determined whether the time required for the eject cam 86 to make one rotation has elapsed. If "NO" in step S5, the process waits until the predetermined time has elapsed. On the other hand, if "YES" in step S5, the process proceeds to step S7.

[0093] In step S7, it is determined whether ejection has been detected. That is, a detection signal is acquired from the arm position detection sensor 96, and it is determined whether the eject arm 90 has reached the eject position during the predetermined time while the motor 72 is rotating in reverse. If the answer is "YES" in step S7, the process proceeds to step S9, where a stop signal is sent to the motor 72, and the ejection process is terminated. On the other hand, if the answer is "NO" in step S7, the process proceeds to step S11.

[0094] In step S11, it is determined whether the set value of the rotation speed N is equal to or greater than a predetermined value (for example, 700 [ppm]). If the answer is "YES" in step S11, proceed to step S13. In step S13, a stop signal is sent to motor 72 and an error notification is executed. For example, a control signal is sent to the display of the operation panel, and a message indicating that an ejection error has occurred is displayed on the display. Thereafter, this ejection process is terminated. On the other hand, if the answer is "NO" in step S11, proceed to step S15. In step S15, the set value of the rotation speed N of motor 72 is increased. That is, the rotation speed N of motor 72 is set to a high rotation speed (for example, 700 [ppm]), and return to step S3.

[0095] As described above, this embodiment employs a coil spring one-way clutch, thereby enabling the downsizing of the driving force transmission device 100 (and thus the push-out mechanism 80, which is an example of a driving force transmission mechanism). Furthermore, the rotation speed of the motor 72 (and thus the rotation speed of the drive gear 82, which is an example of a drive-side rotating member) is increased in stages, so that the driving force can be reliably transmitted and the push-out operation can be reliably performed even if there are manufacturing errors in the components. Furthermore, by increasing the rotation speed of the motor 72 in stages, it is possible to prevent the toner cartridge 32 from popping out at high speed and the upper limit of the torque limiter from increasing, thereby ensuring safety and preventing a shortened service life of the components.

[0096] The configuration of the ejection mechanism 80 described above is merely an example, and can be modified as appropriate without departing from the spirit of the present invention. For example, in the above embodiment, a planar cam is used as the cam member (eject cam) of the ejection mechanism, and this is used in combination with an eject lever, but a three-dimensional cam can also be used as the cam member. That is, in the above embodiment, the eject arm (driven member) receives driving force from the eject cam (driven-side rotating member) of the driving force transmission device via the eject lever, but the driving force may also be transmitted directly from the eject cam.

[0097] In the above-described embodiment, a coil spring with a rectangular cross section (i.e., a square spring) is used, but the cross-sectional shape of the coil spring is not particularly limited, and for example, a coil spring with a circular cross section can also be used. Furthermore, although a cam member is used as the driven rotating member, the driven rotating member may also be a gear member. Furthermore, when increasing the rotational speed of the driving rotating member in stages, the rotational speed of the motor 72 is increased in two stages, low speed (300 [ppm]) and high speed (700 [ppm]), but it may also be increased in three or more stages (e.g., low speed, medium speed, and high speed).

[0098] Furthermore, in the above-described embodiment, the displacement of the eject arm (driven member) is directly detected by the arm position detection sensor, but the displacement of the eject arm may be indirectly detected by detecting the displacement of the toner cartridge. In other words, the arm position detection sensor (displacement detection sensor) also includes the toner cartridge position detection sensor.

[0099] Furthermore, although a color printer has been exemplified as the image forming apparatus in the above embodiment, the image forming apparatus may also be a monochrome printer. Also, the image forming apparatus does not need to be limited to a printer, but may also be a copier, facsimile, or a multifunction machine having these functions.

[0100] Furthermore, in the above-described embodiment, a toner cartridge is exemplified as a consumable container, but the consumable container is not limited to a toner cartridge and may be a toner bottle. Furthermore, liquid toner may be used as the consumable toner. In this case, the consumable container is a liquid toner container. Furthermore, in the above-described embodiment, an electrophotographic image forming apparatus is exemplified, but this does not necessarily mean that it is limited to this. In the case of an inkjet image forming apparatus, the consumable is ink. Therefore, the consumable container that stores the consumable ink is an ink cartridge or an ink bottle. Furthermore, the drive force transmission mechanism according to the present invention can be applied to devices other than image forming apparatuses.

[0101] Furthermore, the specific numerical values ​​and part shapes given above are merely examples and can be changed as appropriate according to the needs of product specifications, etc. [Explanation of symbols]

[0102] 10...Image forming device 10a...Device body 32...Toner cartridge (consumable container) 52...Cartridge storage section (consumables container storage section) 70...Drive unit 72...Motor 80...Extrusion mechanism (driving force transmission mechanism) 82 ... Drive gear (drive side rotating member) 84... Coil spring 86 ... Eject cam (driven rotating member) 88...Eject lever 90...Eject arm (driven member, arm member) 94 ... biasing member 96...Arm position detection sensor (displacement detection sensor) 98...Support shaft 100 ... Driving force transmission device 150...CPU (motor control unit)

Claims

1. A driving force transmission mechanism including a driving force transmission device that transmits driving force from a motor to a driven member, The driving force transmission device is support shaft, a drive-side rotating member having a first cylindrical portion through which the support shaft is inserted and attached rotatably to the support shaft; a driven-side rotating member having a second cylindrical portion through which the support shaft is inserted, the driven-side rotating member being attached adjacent to the driving-side rotating member so as to be rotatable with respect to the support shaft, and transmitting a driving force to the driven member; a coil spring into one end of which the first cylindrical portion is press-fitted and into the other end of which the second cylindrical portion is press-fitted, the coil spring transmitting a driving force of the driving-side rotating member to the driven-side rotating member when the driving-side rotating member is rotated in a first direction; the motor that rotates the drive-side rotating member; and a motor control unit for controlling the operation of the motor; The motor control unit controls the motor so as to increase the rotation speed of the driving-side rotating member in stages when transmitting driving force from the driven-side rotating member to the driven member.

2. a displacement detection sensor for detecting the displacement of the driven member; 2. The driving force transmission mechanism according to claim 1, wherein the motor control unit controls the motor to increase the rotational speed of the driving-side rotating member when the displacement of the driven member is not detected by the displacement detection sensor and the set value of the rotational speed of the driving-side rotating member has not reached a predetermined value.

3. 3. The driving force transmission mechanism according to claim 2, wherein the motor control unit stops the motor when the displacement detection sensor does not detect a displacement of the driven member and a set value of the rotational speed of the driving-side rotating member reaches a predetermined value.

4. 4. The driving force transmission mechanism according to claim 2, wherein the motor control unit stops the motor when the displacement of the driven member is detected by the displacement detection sensor.

5. 3. The driving force transmission mechanism according to claim 1, wherein when a torque equal to or greater than a predetermined value is applied to the driven-side rotating member while the driving-side rotating member is rotated in the first direction, the first cylindrical portion or the second cylindrical portion rotates freely relative to the coil spring.

6. 3. The driving force transmission mechanism according to claim 1, wherein the first direction in which the driving-side rotating member rotates during driving force transmission is a direction in which the coil spring contracts in diameter.

7. An image forming apparatus that forms an image on a sheet using consumables, a consumables container storage section provided in the device body; a consumable container that is removably accommodated in the consumable container storage section; and a push-out mechanism provided in the device body for pushing out the consumable container stored in the consumable container storage section to a position where the consumable container can be removed; The extrusion mechanism includes: support shaft, a drive-side rotating member having a first cylindrical portion through which the support shaft is inserted and attached rotatably to the support shaft; a driven-side rotating member having a second cylindrical portion through which the support shaft is inserted, the driven-side rotating member being adjacent to the drive-side rotating member and rotatably attached to the support shaft; a coil spring into which the first cylindrical portion is press-fitted at one end and the second cylindrical portion is press-fitted at the other end, the coil spring transmitting the driving force of the driving-side rotating member to the driven-side rotating member when the driving-side rotating member is rotated in a first direction; an arm member that displaces in accordance with the rotation of the driven rotation member to push out the consumable container; a motor that rotates the drive-side rotating member; and a motor control unit that controls the operation of the motor; An image forming apparatus, wherein the motor control unit controls the motor to gradually increase the rotational speed of the drive-side rotating member when transmitting a driving force from the driven-side rotating member to the arm member to push out the consumable container.

8. an arm position detection sensor for detecting displacement of the arm member; 8. The image forming apparatus according to claim 7, wherein the motor control unit controls the motor to increase the rotation speed of the driving side rotating member when the arm position detection sensor does not detect displacement of the arm member and the set value of the rotation speed of the driving side rotating member has not reached a predetermined value.

Images