Imaging device

Abstract

An imaging apparatus includes: a limiting member; a driven gear including a limited portion; a planetary gear mechanism including: an input portion for transmitting a driving force from a drive source; an output portion for transmitting the driving force to the driven gear; and a stopping member configured to stop rotation along a first rotation direction and allow the stopped portion to rotate along a second rotation direction opposite to the first rotation direction, wherein when the input portion rotates along the first direction, the stopping member stops the rotation, and the output portion causes the driven gear to rotate along a release direction opposite to the limiting direction; when the rotation of the driven gear along the limiting direction is limited and the input portion rotates along the second direction opposite to the first direction, the stopped portion rotates along the second rotation direction.

Description

Technical Field

[0001] This invention relates to an imaging device. Background Technology

[0002] In imaging devices such as electrophotographic systems, photosensitive drums, conveyor rollers, etc., are driven by motors. Driving force is transmitted from the motor to the object to be driven via a transmission system (e.g., gears and belts). Here, when the object to be driven, or one of the components included in the transmission system, rotates due to an external force, other components connected to the transmission system also rotate together. For example, when a rotating body whose rotation in one direction is restricted exists in the transmission system and that rotating body receives a rotational force in the restricted direction due to an external force, the transmission system, the shaft supporting the transmission system, etc., may be damaged due to the load applied to them.

[0003] Japanese Patent Application Publication No. 2016-175217 discloses a structure in which the stiffness of the support portion of the drive component is reduced, and the support portion bends and skips teeth when a predetermined torque is applied, thereby preventing damage. However, in the method of Japanese Patent Application Publication No. 2016-175217, the support portion may bend even during normal use of the device, thus posing a risk of reduced strength of the transmission system.

[0004] Therefore, there is a need for an imaging device equipped with a transmission system comprising a rotating body whose rotation is restricted, and the device having a novel construction to prevent damage to the transmission system even when further rotational force is applied in the restricted direction.

[0005] The present invention was developed in consideration of the above-mentioned problems. The object of the present invention is to provide an imaging device equipped with a transmission system including a rotating body, the rotation of which is restricted to prevent damage to the transmission system. Summary of the Invention

[0006] This invention provides an imaging apparatus for forming an image on a recording material, the imaging apparatus comprising:

[0007] Limiting components;

[0008] The driven gear includes a restricted portion that can contact the restricting member, wherein when the restricted portion contacts the restricting member, the rotation of the driven gear in the restricting direction is restricted;

[0009] A planetary gear mechanism comprising: an input section configured to receive a driving force transmitted from a drive source; an output section configured to transmit the driving force to a driven gear; and a stopped section; and

[0010] A stopping component is configured to stop the rotation of the stopped portion in a first rotational direction, and to allow the stopped portion to rotate in a second rotational direction opposite to the first rotational direction, wherein...

[0011] When the input section rotates in the first direction, the stopping component stops the rotation of the stopped section in the first rotation direction, and the output section causes the driven gear to rotate in the release direction opposite to the limiting direction.

[0012] When the driven gear is restricted from rotating in the limiting direction and the input part rotates in the second direction opposite to the first direction, the stopped part rotates in the second rotation direction.

[0013] Other features of the invention will become clear from the following description of exemplary embodiments with reference to the accompanying drawings. Attached Figure Description

[0014] Figure 1 This is a cross-sectional explanatory diagram showing the structure of the imaging device according to Embodiment 1;

[0015] Figure 2 The diagram illustrates the structure during transfer separation according to Example 1;

[0016] Figure 3A This illustrates the operation during transfer separation according to Example 1;

[0017] Figure 3B This is another view showing the operation during the release of the transfer separation according to Embodiment 1;

[0018] Figure 4 The structure of the transmission system according to Embodiment 1 is shown;

[0019] Figure 5A and 5B The structure of the planetary gear mechanism according to Embodiment 1 is shown;

[0020] Figure 6A This illustrates the operation of the transmission system in Embodiment 1 when the driven gear rotates in the release direction;

[0021] Figure 6B This is another view showing the operation of the transmission system in Embodiment 1 when the driven gear rotates in the release direction;

[0022] Figure 7 The structure and arrangement of the biasing device according to Embodiment 1 are shown;

[0023] Figure 8A This illustrates the operation of the transmission system in Example 1 when the driven gear rotates in the separation direction;

[0024] Figure 8BThis is another view showing the operation of the transmission system in Embodiment 1 when the driven gear rotates in the separation direction;

[0025] Figure 9 This illustrates the operation of the sun gear according to Embodiment 1 rotating without engaging with the stop component;

[0026] Figure 10 This is a partially enlarged view showing the structure of the stop component and the sun gear according to Embodiment 1;

[0027] Figure 11 This is a partially enlarged view showing the construction of the stop component and the sun gear according to a variation example;

[0028] Figure 12 This describes the drive connection between the processing box and the main body of the device;

[0029] Figure 13 The structure of the transmission system according to Embodiment 2 is shown;

[0030] Figure 14 This illustrates how the sun gear according to embodiment 2 engages with the stop component; and

[0031] Figures 15A to 15F This illustrates the variations in the relationship between planetary gear systems, motors, and driven gears. Detailed Implementation

[0032] Preferred embodiments of the invention will now be described in detail with reference to the accompanying drawings. However, the dimensions, materials, shapes, and relative positions of the components described in the following embodiments should be appropriately varied according to the construction of the device to which the invention is applied and various conditions. Therefore, this specification does not limit the scope of the invention unless specifically stated otherwise.

[0033] Example 1

[0034] Schematic structure of imaging device

[0035] The following will refer to Figure 1This section introduces an imaging apparatus according to Embodiment 1, which is equipped with a mechanism for preventing damage during reverse rotation of the transmission system. In this embodiment, a laser beam printer is used as an example to illustrate the imaging apparatus, and the mechanism for preventing damage during reverse rotation of the transmission system is described when applied to the separating portion of a transfer roller (which transfers toner onto paper). According to the invention, the mechanism for preventing damage during reverse rotation of the transmission system is configured to use a planetary gear mechanism to prevent rotation without reducing the strength of the transmission system against input in the direction limiting rotation, and this technique can be applied to a driven object (for which rotation in a specific direction is limited). Its application is not particularly limited. A transmission system is a set of mechanical elements arranged in a path for transmitting driving force from a drive source (e.g., a motor) to a driven object, and includes mechanical elements such as gears, planetary gear mechanisms, etc., which are rotating bodies. The transmission system may also include elements such as shafts, drive belts, etc.

[0036] Figure 1 This is a cross-sectional view of the imaging apparatus 1. When the photosensitive drum 2 rotates, its surface (image-carrying component) is uniformly charged by the charging roller 3, which serves as a charging device. The photosensitive drum 2 is irradiated with a laser corresponding to the image information from the optical device 4, so that an electrostatic latent image corresponding to the image information is formed on the photosensitive drum 2. A toner image (developer image) is formed by supplying toner (developer) carried by the developing roller 5, which serves as a developer-carrying component, to the electrostatic latent image formed on the photosensitive drum 2.

[0037] Simultaneously, in parallel with the formation of the toner image, the recording material P is separated and supplied sheet by sheet via the pickup roller 6 and the paper supply roller 7. The recording material P is conveyed to the transfer roller 9, which serves as a transfer device, via the transfer rollers 8a and 8b, and the toner image formed on the photosensitive drum 2 is transferred onto the recording material P. The recording material P with the toner image transferred onto it is then conveyed to the fixing device 10. This fixing device 10 has a drive roller 10a and a fixing roller 10b containing a heater. The drive roller 10a and the fixing roller 10b apply heat and pressure to the recording material P so that the transferred toner image is fixed onto the recording material P. The recording material P is then discharged via the discharge roller 11. As described above, the imaging device 1 forms an image on the recording material P.

[0038] Based on program or user input, the control unit 200, which controls each component, executes various processes performed by the imaging device. Computers, control circuits, etc., can be used as the control unit 200. In this embodiment, the imaging device 1 has a main body 1a and a processing cartridge 18, which is detachably attached to the main body 1a. The processing cartridge 18 includes a photosensitive drum 2, a charging roller 3, and a developing roller 5. In this embodiment, an example where the processing cartridge 18 can be attached to and detached from the main body 1a of the imaging device 1 will be described; however, the present invention is not limited to imaging devices 1 employing such a system (in which the processing cartridge 18 can be attached to and detached from the main body 1a).

[0039] Restriction of rotation direction of transmission system

[0040] The following will refer to Figure 2 , 3A Sections 3B and 4 describe the limitation of the rotation direction of the transmission system 90 according to Embodiment 1. Figure 2 This is a perspective view showing the configuration during transfer separation. Figure 3A It is a plan view showing the configuration during transfer separation. Figure 3B It is a plan view showing the configuration when the transfer separation is released. Figure 4 This is a perspective view showing the configuration of the transmission system that transmits the driving force for releasing the transfer separation. Figure 3A and 3B In the middle, the direction from the back side to the front side of the paper surface is the direction in which the transfer roller 9 approaches the photosensitive drum 2, and the opposite direction is the direction in which the transfer roller 9 moves away from the photosensitive drum 2.

[0041] The imaging device 1 has a motor M and a transmission system 90 that transmits the driving force of the motor M. The transmission system 90 includes a planetary gear mechanism 100 and a driven gear 20. In this embodiment, the transmission system 90 also includes an idler gear 40. The motor M is configured to drive the planetary gear mechanism 100 and the processing cartridge 18.

[0042] In this embodiment, the rotating body of the processing cartridge 18 is driven by the driving force of the motor M, but the motor M can also drive components other than the rotating body. Furthermore, in this embodiment, the photosensitive drum 2 is driven as the rotating body, but other rotating bodies besides the photosensitive drum 2, such as the developing roller 5, can also be driven.

[0043] The transfer roller 9 is preferably separated from the photosensitive drum 2 to avoid friction between the transfer roller 9 and the photosensitive drum 2, for example, when the imaging device 1 is not in use. The imaging device 1 has a separation mechanism for separating the transfer roller 9 from the photosensitive drum 2. The separation mechanism has a separation component (holding component) 13 and a switching cam (switching component, moving component, slider component) 14.

[0044] The transfer roller 9 is supported by bearing 12. For example... Figure 3A As shown, when the transfer roller 9 separates, the bearing 12 is held by the separation member 13, which restricts the movement of the transfer roller 9 in the direction of contact with the photosensitive drum 2. Specifically, the holding portion 13a of the separation member 13 holds the bearing 12, thereby keeping the transfer roller 9 separated from the photosensitive drum 2. The separation member 13 is biased toward the switching cam 14 in the direction of arrow A in the figure. The switching cam 14 is provided with a receiving portion 14a, and the receiving portion 13b of the separation member 13 contacts the receiving portion 14a, thus holding the separation member 13 in the position of holding the bearing 12. At this time, the separation member 13 acts as a holding member, which uses the holding portion 13a to hold the bearing 12 when the transfer roller 9 and the photosensitive drum 2 are separated from each other.

[0045] The switching cam 14 is provided with a rack (gear portion) 15, which meshes with a driven gear 20. The driven gear 20 is a gear that transmits the driving force for releasing the disengaged state of the transfer roller 9, and is arranged downstream of the planetary gear mechanism in the path for transmitting the driving force.

[0046] Driven gear 20 rotates in the release direction 21, causing switching cam 14 to rotate along... Figure 3A The movement is in the direction of arrow B. The movement of the separating component 13 releases the restriction in the direction of contact between the transfer roller 9 and the photosensitive drum 2, and the transfer roller 9 contacts the photosensitive drum 2.

[0047] Specifically, the switching cam 14 is provided with a recess 14b as a release portion. Along the switching cam 14... Figure 3A When the movement is in the direction of arrow B, the receiving portion 13b separates from the receiving portion 14a and is received by the recess 14b. For example... Figure 3B As shown, when the received portion 13b is received by the recess 14b, the holding portion 13a is separated from the bearing 12. As a result, the bearing 12 and the transfer roller 9 move, causing the transfer roller 9 to contact the photosensitive drum 2. Thus, the switching cam 14 slides in the direction of arrow B, causing the contact position of the received portion 13b to change between the receiving portion 14a and the recess 14b, thereby enabling the relationship between the transfer roller 9 and the photosensitive drum 2 to switch between a contact state and a separation state. Therefore, the switching cam 14 can be referred to as a switching component, a moving component, or a slider component.

[0048] In this embodiment, the driven gear 20 is connected to the planetary gear mechanism 100 via the idler gear 40, and the driving force of the motor M is transmitted to the driven gear 20 through the planetary gear mechanism 100 and the idler gear 40. The driven gear 20 has a gear portion formed in a portion of it in the circumferential direction. As the idler gear 40 continues to rotate the driven gear 20 in the release direction 21, the driven gear 20 moves to a position where the gear portion of the driven gear 20 no longer meshes with the idler gear 40. That is, by rotating in the release direction 21, the driven gear 20 can move to a disengaged position, in which the connection between the driven gear 20 and the planetary gear mechanism 100 is severed. The planetary gear mechanism 100 and the driven gear 20 can directly mesh with each other.

[0049] In this embodiment, when the gear portion of the driven gear 20 moves to a position where it no longer meshes with the idler gear 40, the receiving portion 13b of the separating member 13 contacts the inclined surface between the receiving portion 14a and the recess 14b. At this time, because the separating member 13 moves along... Figure 3A The direction of arrow A shown is biased, so switching cam 14 moves along... Figure 3A The direction of arrow B is further moved. As a result, the driven gear 20 rotates further in the release direction 21 via the rack 15, and the gear portion of the driven gear 20 separates from the idler gear 40. The switching cam 14 and rack 15 reach the restricted release position, and the receiving portion 13b is received by the recess 14b. Figure 3B ).

[0050] The components can also be arranged such that when the gear portion of the driven gear 20 moves to a position where it no longer meshes with the idler gear 40, the switching cam 14 and the rack 15 simultaneously reach the limit release position, and the receiving portion 13b is received by the recess 14b.

[0051] Therefore, when the imaging device 1 in this embodiment is not used (new product), the transfer roller 9 is separated from the photosensitive drum 2, and when the imaging device 1 is used, the transfer roller 9 is in contact with the photosensitive drum 2.

[0052] The driven gear 20 has an arm 20a (as a restricted part) that can contact and is restricted by a restricting member 30. Regarding the rotation direction of the driven gear 20, the direction in which the arm 20a approaches the restricting member 30 is called the separation direction (restriction direction) 22. Simultaneously, the release direction 21 is opposite to the separation direction 22 and is the direction in which the arm 20a moves away from the restricting member 30. When the arm 20a contacts the restricting member 30, the rotation of the driven gear 20 along the separation direction 22 is restricted. For this purpose, the restricting member 30 is fixed so that it does not move even when receiving rotational force from the driven gear 20, and is arranged, for example, in the device body 1a. Although in Figure 4In the example, the limiting member 30 is a member with a limiting surface, but the structure of the limiting member 30 is not limited to this, as long as the limiting member has a part that can contact the arm 20a.

[0053] In other words, the rotation of the driven gear 20 along the separation direction 22 is restricted by the limiting member 30, thereby preventing damage or separation failure due to excessive movement of the switching cam 14 and maintaining the proper position of the switching cam 14. As described above, the driven gear in this specification refers to a gear that is unrestricted when rotating in one direction (release direction 21), but whose rotation is restricted at a specific position by the limiting member 30 when rotating in another direction (separation direction 22).

[0054] like Figure 4 As shown, when the arm 20a contacts the limiting member 30 and the rotation of the driven gear 20 along the separation direction 22 is restricted, the receiving portion 13b of the separating member 13 is received by the receiving portion 14a of the switching cam 14, and the transfer roller 9 separates from the photosensitive drum 2.

[0055] Here, we assume that with the conveyor roller 9 separated and the driven gear 20 restricted by the limiting member 30, a force that rotates the driven gear 20 along the separation direction 22 is applied to the planetary gear mechanism 100 connected to the driven gear 20. In this case, because the driven gear 20 cannot rotate along the separation direction 22, the transmission system 90 cannot rotate, and a load is applied to the gear and the shaft supporting the transmission system. Therefore, it is preferable to release the force that rotates the driven gear 20 along the separation direction 22.

[0056] Planetary gear mechanism

[0057] The following will use Figure 4 , 5A Sections 5B, 6A, 6B, and 7 introduce planetary gear mechanisms. Figure 5A and 5B Indicates a planetary gear mechanism. Figure 6A and 6B This indicates the operation of the transmission system when the driven gear rotates in the release direction.

[0058] The planetary gear mechanism 100 is configured to transmit driving force from the motor M and includes: an input gear (input portion, input component, internal gear) 110, which has an internal gear portion 111; and a first planetary gear 120 and a second planetary gear 121, which mesh with the internal gear portion 111. The input gear 110 is configured to receive the driving force transmitted from the motor M. Furthermore, the planetary gear mechanism 100 has a planetary carrier (output portion, output component) 130 serving as a carrier and a sun gear (stopped portion) 140 meshing with the first planetary gear 120 and the second planetary gear 121. The planetary carrier 130 includes a first support shaft 131 and a second support shaft 132, on which the first planetary gear 120 and the second planetary gear 121 are rotatably supported.

[0059] Additionally, the planetary carrier 130 is connected to the driven gear 20 via an idler gear 40, and is configured to transmit the driving force from the motor M to the input gear 110 to the driven gear 20. In an alternative configuration, the planetary carrier 130 and the driven gear 20 can mesh directly without the idler gear 40 positioned between them.

[0060] The imaging device 1 also includes a stop (stopping member) 50, which is configured to stop the sun gear 140 when the input gear 110 rotates in the first direction 101. In this embodiment, the stop is configured to move in a direction intersecting (preferably orthogonal) to the axis of rotation of the sun gear 140.

[0061] The first planetary gear 120 and the second planetary gear 121 are rotatably supported by the first support shaft 131 and the second support shaft 132. The rotation of the first planetary gear 120 and the second planetary gear 121 about the first support shaft 131 and the second support shaft 132 is referred to as the rotation of the first planetary gear 120 and the second planetary gear 121. Furthermore, as described below, the first planetary gear 120 and the second planetary gear 121 can rotate about the sun gear 140. When the first planetary gear 120 and the second planetary gear 121 rotate about the sun gear 140, the first support shaft 131 and the second support shaft 132 also rotate about the sun gear 140. As a result, the planetary carrier 130 rotates.

[0062] When the driving force is applied to the input gear 110 along the first direction 101, the driving force is transmitted to the first planetary gear 120 and the second planetary gear 121 through the internal gear portion 111. At this time, the driving force acts on the first support shaft 131 and the second support shaft 132 of the planetary carrier 130 and on the sun gear 140 through the first planetary gear 120 and the second planetary gear 121.

[0063] The sun gear 140 has a first retaining surface 145, a second retaining surface 146, and a first portion 141 and a second portion 142 protruding from the retaining surfaces to be locked. When the stop 50 is in a position separated from the first portion 141 and the second portion 142 to be locked, the sun gear 140 rotates, simultaneously rubbing against either the first retaining surface 145 or the second retaining surface 146. In the following description, it is assumed that the stop 50 rubs against the first retaining surface 145.

[0064] Simultaneously, the driving force that rotates the driven gear 20 along the release direction 21 acts on the planetary carrier 130 along the first direction 101. The planetary carrier 130 is connected to the driven gear 20, which meshes with the rack 15 of the switching cam 14. Due to the frictional resistance acting on the switching cam 14 and the bias of the separation component 13 toward the switching cam 14, a certain force is required through the driven gear 20 and the rack 15 to rotate the planetary carrier 130 and move the switching cam 14.

[0065] As a result, when the stopper 50 disengages from the first part 141 to be locked and the second part 142 to be locked, the first planetary gear 120 and the second planetary gear 121... Figure 6A The planetary carrier 130 rotates counterclockwise while the planetary carrier 130 does not rotate. Due to the rotation of the first planetary gear 120 and the second planetary gear 121, the driving force is transmitted to the sun gear 140 so that it rotates in a second direction 102, which is different from the first direction 101.

[0066] Here, the stopper 50 is biased by the biasing device 160 so as to contact the first retaining surface 145. Figure 7 An example of the construction and arrangement of such a biasing device 160 is shown. The biasing device 160, which is an elastic body, is connected to the stop 50 at one end and to the main frame 170 at the other end. When the biasing device 160 is included in the device, it applies a rotational biasing force that pushes the stop 50 toward the sun gear 140. A spring can be used as the biasing device 160. In this embodiment, the biasing device 160 is a torsion coil spring.

[0067] During the rotation of the sun gear 140 along the second direction 102, the rotation of the sun gear 140 along the second direction 102 is restricted when the stop 50, biased by the biasing device 160 towards the first holding surface 145, engages with the first portion 141 to be locked. That is, the stop 50 is configured to restrict and stop the rotation of the sun gear 140 along the first rotation direction when the input gear 110 rotates along the first direction 101.

[0068] In this embodiment, when the input gear 110 rotates along the first direction 101, the rotation of the sun gear 140 is restricted and stops due to contact between the locking first portion 141 or the locking second portion 142 and the stopper 50. However, the invention is not limited to this configuration. For example, another gear meshing with the sun gear 140 may have a configuration corresponding to the locking first portion 141 and the locking second portion 142, and may contact the stopper 50.

[0069] The following will refer to Figure 10 The engagement between the stop 50 and the first portion 141 to be locked in this embodiment is illustrated by a partially enlarged view. The first portion 141 to be locked rises from the first retaining surface 145 at the raised base portion 141c to form a locking surface 141b protruding from the first retaining surface 145. The gear-side locking surface 141b forms a surface extending from the raised base portion 141c to the raised top portion 141a. The stop 50 contacts and rubs against the first retaining surface 145 primarily through the top portion 50b. Furthermore, when engaged with the first portion 141 to be locked, the locking device-side locking surface 50a contacts either the gear-side locking surface 141b or the raised top portion 141a.

[0070] When the input gear 110 rotates along the first direction 101 and the rotation of the sun gear 140 is restricted, the first planetary gear 120 and the second planetary gear 121 rotate (revolve) about the rotation axis of the sun gear 140 along the first direction 101, while... Figure 6A It rotates counterclockwise (direction 103).

[0071] Because each planetary gear is attached to a first support shaft 131 and a second support shaft 132 located on the planetary carrier 130, the planetary carrier 130 also rotates along the first direction 101 along with the movement of each planetary gear. The driving force from the planetary carrier 130 is transmitted to the driven gear 20 through the idler gear 40, and the driven gear 20 rotates along the release direction 21. That is, when the sun gear 140 stops and the input gear 110 rotates along the first direction 101, the planetary gear mechanism 100 causes the driven gear 20 to rotate along the release direction 21 via the planetary carrier 130.

[0072] In the case shown here, two planetary gears and two support shafts are provided, but this configuration is not limiting. For example, similar effects can be achieved even when the number of planetary gears and support shafts is one, three, or more.

[0073] Mechanism used to prevent damage when the rotation of the transmission system is restricted.

[0074] The following will refer to Figure 8A , 8B Section 9 introduces a mechanism to prevent damage when the rotation of a transmission system is restricted. Figure 8A and 8B This describes the operation of the transmission system when the driven gear 20 rotates along the separation direction 22, and Figure 9 This illustrates how the sun gear 140 rotates without engaging with the stopper 50 via the inclined surface portion.

[0075] When a driving force is applied to the input gear 110 along the second direction 102, the driving force causing rotation along the separation direction 22 is transmitted to the driven gear 20, contrary to the above. However, the driven gear 20 is prevented from rotating along the separation direction 22 by the limiting member 30, and the planetary carrier 130 transmitting the driving force is in a locked state. Therefore, the first planetary gear 120 and the second planetary gear 121 rotate about the first support shaft 131 and the second support shaft 132 in the rotation direction 122, respectively, and drive the sun gear 140 along the first direction 101. That is, the direction of the force received by the sun gear 140 due to the rotation of the input gear 110 along the first direction 101 is opposite to the direction of the force received by the sun gear 140 due to the contact between the arm 20a and the limiting member 30 and the rotation of the input gear 110 along the second direction 102.

[0076] In this embodiment, the stopper 50 restricts the rotation of the sun gear 140 and stops the sun gear 140 when it rotates along the second direction 102. Simultaneously, the stopper 50 allows the sun gear 140 to rotate along the first direction 101. Therefore, when the arm 20a contacts the limiting member 30 and the input gear 110 rotates along the second direction 102, which is opposite to the first direction 101, the sun gear 140 rotates along the first direction 101. At this time, the stopper 50 allows the sun gear 140 to rotate along the first direction 101. That is, the stopper 50 is configured to allow the sun gear 140 to rotate along the second direction, which is opposite to the first rotation direction.

[0077] The relationship between the sun gear 140 and the stop 50 will be described below when the arm 20a contacts the limiting member 30 and the input gear 110 rotates along the second direction 102. The sun gear 140 is provided with a first inclined portion 143, and when the sun gear 140 rotates along the first direction 101, the stop 50 is lifted by the first inclined portion 143 (e.g., ...). Figure 9As shown), the stop 50 moves over the second portion 142 to be locked, so as to contact the second retaining surface 146. As the sun gear 140 rotates further, the stop is similarly lifted by the second inclined portion 144 and moves over the first portion 141 to be locked, so as to contact the first retaining surface 145 again. That is, the first inclined portion 143 and the second inclined portion 144 are inclined portions configured to cause the stop 50 to move when the sun gear 140 rotates in the second rotational direction.

[0078] In the Figure 10 In the example shown in the enlarged view, the second inclined portion 144 includes: a first portion 144a smoothly connected to the second retaining surface; a second portion 144b smoothly connected to the first portion 144a; and a third portion 144c smoothly connected to the second portion 144b. The third portion 144c is connected to the locking surface 141b via the raised top portion 141a of the first portion 141 to be locked, thereby giving the surface a discontinuous cliff shape. Therefore, the second inclined portion 144 has a portion smoothly connected to and inclined from the second retaining surface 146, and a portion connected to the first retaining surface 145 via the first portion 141 to be locked. In the portion connected to the first retaining surface 145, the surface of the first retaining surface 145 and the surface of the second inclined portion 144 are discontinuous due to the presence of the inclination angle.

[0079] Using the above-described structure, the sun gear 140 can rotate along the first direction 101 without being restricted by the stop 50. That is, when the sun gear 140 rotates along the first direction 101, the top portion 50b (or contact surface 50c) of the stop 50 smoothly contacts and rubs against the second inclined portion 144 to reach the raised top portion 141a of the first portion 141 to be locked, without restricting its movement. At the raised top portion 141a, the stop 50 moves discontinuously to the first retaining surface 145 by biasing force. As a result, even when the driven gear 20 is driven along the separation direction 22 where rotation is restricted, the sun gear 140 idles to release the driving force, thus preventing the transmission system from locking. In other words, it is possible to prevent the transmission system from locking and to prevent damage to the transmission system, shafts, etc.

[0080] Furthermore, there is no need to deform the support shaft of the gear supporting the transmission system 90 or cause the gears to skip teeth in order to release the driving force. That is, the transmission system 90 is maintained in the engaged state when the sun gear 140 rotates in the second direction 102 to release the driving force. For example, the meshing (connection) between the input gear 110, the first planetary gear 120 and the second planetary gear 121, the sun gear 140 and the planet carrier 130 of the planetary gear mechanism 100 is maintained. Moreover, the meshing (connection) between the planet carrier 130 and the driven gear 20 is maintained through the idler gear 40.

[0081] As described above, when the sun gear 140 rotates along the first direction 101, the stop 50 crawls over the first portion 141 to be locked and the second portion 142 to be locked. After crawling over, the stop again contacts the first retaining surface 145 or the second retaining surface 146. At this time, in this embodiment, the stop 50 moves in a direction intersecting the rotation axis of the sun gear 140.

[0082] Preferably, a first inclined portion 143 and a second inclined portion 144 are present so that when the sun gear 140 rotates in the first direction 101, the stop 50 crawls over the first portion 141 and the second portion 142 to be locked. The force applied by the biasing device 160 in the direction of locking the stop 50 is thus dispersed. As a result, the force applied to the stop 50 from the first portion 141 and the second portion 142 to be locked in the direction of releasing the lock becomes greater than the force applied by the biasing device 160 in the direction of locking the stop 50.

[0083] Simultaneously, when the sun gear 140 rotates along the second direction 102, the stop 50 engages with the first portion 141 to be locked and the second portion 142 to be locked. Therefore, this design ensures that the force applied by the biasing device 160 in the direction of locking the stop 50 becomes greater than the force applied to the stop 50 from the first portion 141 to be locked and the second portion 142 to be locked in the direction of releasing the lock. Therefore, the construction of the stop 50, the locked portion, etc., of the present invention is not limited to that shown in the drawings, and the materials, dimensions, shapes, and structures of the stop 50, the locked portion, the inclined portion, the retaining surface, etc., the biasing force of the biasing device, the momentum of the sun gear, etc., can be designed to satisfy the above-described relationships.

[0084] Furthermore, as described above, in this embodiment, the motor M is configured to drive the planetary gear mechanism 100 and the processing box 18. As a result, the force for moving the processing box 18 is transmitted to the transmission system 90 and then to the input gear 110. That is, the input gear 110 is rotated by mounting the processing box 18 onto and removing it from the device body. Even when the processing box 18 is attached and detached while the arm 20a is in contact with the limiting member 30 and the input gear 110 rotates in the second direction 102, the force acting on the input gear 110 can be released by the rotation of the sun gear 140. Therefore, the processing box 18 can be attached and detached smoothly.

[0085] This will be referenced Figure 12 The drive connection between the processing box 18 and the device body 1a is described. Figure 12 The drive connection between the processing box 18 and the device body 1a is explained. Figure 12 In the illustrated configuration, the processing box 18 has a gear CG, and the main body 1a has a gear MG connected to the motor M and the planetary gear mechanism 100 (specifically, the input gear 110). The gear CG rotates about a rotation axis 180, and the gear MG rotates about a rotation axis 182. The driving force of the motor M is transmitted to the processing box 18 by meshing the gears CG and MG. In this configuration, the processing box 18 can be attached / detached in a direction intersecting the rotation axis 182 of the gear MG (arrow C direction). In this case, the gear MG may rotate when the processing box 18 is attached or detached.

[0086] Because gear MG is connected to motor M and planetary gear mechanism 100, rotation of input gear 110 may occur when the processing cartridge 18 is attached or detached. Even in this configuration, the force acting on input gear 110 can be released by rotating sun gear 140. Therefore, processing cartridge 18 can be attached and detached smoothly. The above-described drive connection between processing cartridge 18 and device body 1a is merely exemplary, and the present invention can also be applied to imaging devices with configurations different from those described above.

[0087] Here, a case is shown where the sun gear has two lockable portions, two retaining surfaces, and two tilting portions; however, this configuration is not limiting. For example, similar effects can be achieved even when there are one or three or more lockable portions, retaining surfaces, and tilting portions.

[0088] Furthermore, although a configuration in which the stop 50 oscillates about the rotation axis has been shown, this configuration is not limiting. For example, even when locking is achieved through linear motion, a similar effect can be obtained as long as the bias direction allows for smooth movement of the tilted portion.

[0089] Furthermore, although the shape of the portion to be locked protruding outward from the retaining surface along the radial direction of the sun gear has been shown, this shape is not limiting. For example, even if the recess has a shape that retracts inward along the radial direction of the sun gear, a similar effect can be obtained as long as it can engage with the stop 50. Figure 11 An example of such a variation is shown, wherein the stopper 50 engages with the first lockable portion 141 having a retractable shape in one rotational direction, but is able to contact the first retaining surface in another rotational direction via the inclined portion 144.

[0090] Furthermore, although a drive system for switching between the separated and contact states of the transfer roller 9 has been described as an example, this configuration is not limiting. For example, the invention can also be applied to a drive system for switching between the separated and contact states between the photosensitive drum 2 and the developing roller 5 of the processing cartridge. In addition, the invention is applicable not only to drive systems for switching between separated and contact states, but also to any drive system in which a driving force can be further applied in the limiting direction when rotation is limited.

[0091] In other words, the driven gear 20 can switch between the separation state and the contact state of the transfer roller 9, or between the separation state and the contact state between the developing roller 5 and the photosensitive drum 2.

[0092] Example 2

[0093] The following will refer to Figure 13 and 14 This section introduces a mechanism according to Embodiment 2 for preventing damage when the rotation of the transmission system is restricted. Components identical to those described above are given the same reference numerals, and their descriptions are omitted. In Embodiment 1, the cross-sections of the first retaining surface 145 and the second retaining surface 146 are shaped to be substantially concentric with the circumference of the sun gear 140. Meanwhile, in Embodiment 2, the first retaining surface and the second retaining surface are surfaces extending in a direction intersecting the rotation axis of the sun gear 140 (more preferably in a perpendicular direction).

[0094] Figure 13 The construction of a transmission system for transmitting the driving force used to release the transfer separation is shown, and Figure 14 The diagram illustrates how the sun gear 140 and the stopper 50 engage.

[0095] When a driving force is applied to the input gear 110 along the second direction 102, the driving force is transmitted to the driven gear 20 to rotate along the separation direction 22. However, rotation along the separation direction 22 is prevented by the limiting member 30, and the planetary carrier 130 that transmits the driving force is in a locked state. Therefore, the first planetary gear 120 and the second planetary gear 121 rotate about the first support shaft 131 and the second support shaft 132 respectively along the rotation direction 122, and drive the sun gear 140 along the first direction 101.

[0096] The sun gear 140 is provided with a first inclined portion 143. When the sun gear 140 rotates along the first direction 101, the stop 50 is lifted by the first inclined portion 143, contacts the first retaining surface 145, and then passes through the second portion 142 to be locked, so as to contact the second inclined portion 144. As the sun gear 140 rotates further, the stop is similarly lifted by the second inclined portion 144, contacts the first retaining surface 145, passes through the first portion 141 to be locked, and then contacts the first inclined portion 143 again. Therefore, the sun gear 140 can rotate along the first direction 101 without being restricted by the stop 50. As a result, even when the driven gear 20 is driven along the separation direction 22 where rotation is restricted, the sun gear 140 idles to release the driving force, thereby preventing the transmission system from locking. That is, it is possible to prevent the transmission system from locking and to prevent damage to the transmission system, shafts, etc.

[0097] Here, a case is shown with two lockable parts, two retaining surfaces, and two inclined parts, but this configuration is not limiting. For example, similar effects can be achieved even when there are one or three or more lockable parts, retaining surfaces, and inclined parts.

[0098] Furthermore, although the construction of the stop oscillation has been shown, it is not limiting. For example, even when locking is achieved through linear motion, a similar effect can be obtained as long as the bias direction allows for smooth movement of the tilted portion.

[0099] Furthermore, although a shape in which the part to be locked protrudes from the retaining surface toward the locking device side along the rotation axis of the sun gear has been shown, this shape is not limiting. For example, even in the case of a shape that retracts toward the side opposite to the locking device along the rotation axis of the sun gear, a similar effect can be obtained as long as it can engage with the locking device.

[0100] Other embodiments

[0101] In the above embodiments, a monochrome imaging device using a single processing box is illustrated and explained, but the present invention is not limited thereto and can also be applied to a panchromatic imaging device using multiple processing boxes.

[0102] Furthermore, in the above embodiments, the printer is used as an example of an imaging device, but the present invention is not limited thereto. For example, other imaging devices such as copiers and fax machines, or other imaging devices of multifunction machines combining these functions, can be used. Similar effects can be obtained by applying the present invention to the drive transmission mechanisms used in these imaging devices.

[0103] Figures 15A to 15F The variations in the relationship between the planetary gear unit, the motor M, and the driven gear 20 are shown.

[0104] In each of the above embodiments, the sun gear 140 is the stopped portion limited by the stopper 50, the input gear 110 is the input portion to which driving force is input from the motor M, and the planetary carrier 130 is the output portion that transmits driving force toward the driven gear 20. However, the present invention is not limited thereto.

[0105] One of the internal gear, sun gear, and planet carrier of the planetary gear unit can be the input part (the driving force is input from the motor M to the input part), one of the other two can be the output part that transmits the driving force toward the driven gear 20, and the remaining one can be the stopped part that is restricted by the stopper 50.

[0106] In any of these configurations, such as in the above embodiment, when the input portion rotates in the first direction, the stopper 50 stops the rotation of the stopped portion in the first rotation direction, and the output portion causes the driven gear 20 to rotate in the release direction 21.

[0107] Simultaneously, when the input part rotates in a second direction opposite to the first direction and the rotation of the driven gear 20 in the separation direction (restriction direction) 22 is restricted, the stopped part rotates in the second rotation direction opposite to the first rotation direction. The stopper 50 allows the stopped part to rotate in the second rotation direction.

[0108] As described above, according to embodiments of this specification, in an imaging apparatus equipped with a transmission system (which includes a rotating body whose rotation is restricted), damage to the transmission system can be prevented while maintaining its strength. That is, in this specification, in a transmission system including a driven gear (as an element) that serves as a rotating body (whose rotation is restricted in one direction), the driven gear is arranged downstream of the planetary gear mechanism's transmission system. Therefore, when the driven gear rotates in an unrestricted direction, the strength of the transmission system does not decrease, and even when the driven gear receives a rotational force in the restricted direction, the sun gear will still rotate. As a result, damage to gears, shafts, etc., can be prevented because no load is applied to the elements of the transmission system. In particular, when the present invention is applied to an imaging apparatus or a multi-functional machine, even when the rotating body of the transmission system rotates in a direction with restricted rotation during attachment or disassembly of a gear-driven cartridge or conveyor roller, the effect of preventing attachment / disassembly failure due to transmission system locking can be achieved.

[0109] According to the present invention, in an imaging device equipped with a transmission system including a rotating body (the rotation of which is restricted), damage to the transmission system can be prevented.

[0110] Although the invention has been described with reference to exemplary embodiments, it should be understood that the invention is not limited to the disclosed exemplary embodiments. The scope of the following claims should be interpreted in the broadest sense to cover all such variations and equivalent structures and functions.

Claims

1. An imaging apparatus for forming an image on a recording material, the imaging apparatus comprising: Limiting components; The driven gear includes a gear portion formed partially along the circumferential direction and a restricted portion that can contact the restricting member, wherein when the restricted portion contacts the restricting member, the rotation of the driven gear along the restricting direction is restricted. A planetary gear mechanism comprising: an input section configured to receive a driving force transmitted from a drive source; an output section configured to transmit the driving force to a driven gear via the gear section; and a stopped section; and A stopping component is configured to stop the rotation of the stopped portion along a first rotational direction, and to allow the stopped portion to rotate along a second rotational direction opposite to the first rotational direction, wherein... When the input section rotates in the first direction, the stopping member stops the rotation of the stopped section in the first rotation direction, and the output section causes the driven gear to rotate in a release direction opposite to the limiting direction. When the driven gear's rotation along the limiting direction is restricted and the input portion rotates along a second direction opposite to the first direction, the stopped portion rotates along the second rotation direction. By rotating in the release direction, the driven gear can be moved to a position where the connection between the driven gear and the planetary gear mechanism is broken.

2. The imaging apparatus according to claim 1, wherein: The planetary gear mechanism includes an internal gear, a sun gear, planetary gears that engage with the internal gear and the sun gear, and a carrier with a support shaft on which the planetary gears are rotatably supported. One of the internal gear, the sun gear, and the carrier is the input part, one of the other two is the output part, and the remaining one is the stopped part.

3. The imaging apparatus according to claim 2, wherein: The sun gear is the stopped part, the internal gear is the input part, and the carrier is the output part.

4. The imaging apparatus according to any one of claims 1 to 3, further comprising: Main body of the device; as well as The box, which is detachably attached to the main body of the device, wherein The drive source is configured to drive the planetary gear mechanism and the housing.

5. The imaging apparatus according to claim 4, wherein: The input section is rotated by mounting the box onto and removing it from the device body.

6. The imaging apparatus according to claim 1, comprising: The part to be locked, among which When the input portion is rotated in the first direction, the stopped portion stops by contacting the portion to be locked with the stopping component.

7. The imaging apparatus according to claim 6, wherein: The portion to be locked has a locking surface, which is disposed on the portion to be stopped and engages with the stopping component. The stopped portion has a retaining surface and an inclined portion. When the stopped portion rotates, the retaining surface contacts and slides against the stopping component. The inclined portion includes a portion that is smoothly connected to and inclined from the retaining surface, and a portion that is connected to the retaining surface through the locking surface.

8. The imaging apparatus according to claim 7, wherein: In the portion where the inclined section is connected to the retaining surface via the locking surface, the retaining surface and the surface of the inclined section are discontinuous.

9. The imaging apparatus according to claim 7, wherein: When the restricted part contacts the restricting member and the input part rotates in the second direction, the stopping member moves from a state of contact with the holding surface of the part to be locked to a state of contact with the inclined part, then crawls over the part to be locked and returns to a state of contact with the holding surface.

10. The imaging apparatus according to claim 7, wherein: The stopping component is biased by a biasing device so that it contacts the stopped portion.

11. The imaging apparatus according to claim 7, wherein: The portion to be locked protrudes outward from the retaining surface along the radial direction of the stopped portion.

12. The imaging apparatus according to claim 7, wherein: The portion to be locked is recessed inward from the retaining surface along the radial direction of the stopped portion.

13. The imaging apparatus according to claim 7, wherein: The retaining surface is a surface that extends in a direction intersecting the rotation axis of the stopped portion, and The portion to be locked protrudes from the holding surface toward the stopping component along the rotation axis of the stopped portion.

14. The imaging apparatus according to claim 7, wherein: The retaining surface is a surface that extends in a direction intersecting the rotation axis of the stopped portion, and The portion to be locked is recessed from the holding surface toward the side opposite to the stopping component along the rotation axis of the stopped portion.

15. The imaging apparatus according to claim 1, wherein: The stopped portion has an inclined portion, which causes the stopping component to move when the stopped portion moves along the second rotation direction.

16. The imaging apparatus according to any one of claims 1 to 3, further comprising: A photosensitive drum on which an electrostatic latent image corresponding to the image information is formed; The developing roller supplies developer to the photosensitive drum in order to form a developer image; as well as A transfer roller that transfers the developer image onto the recording material.

17. The imaging apparatus according to claim 16, wherein: Driven gears switch the contact and separation between the transfer roller and the photosensitive drum.

18. The imaging apparatus according to claim 16, wherein: Driven gears switch the contact and separation between the developing roller and the photosensitive drum.

Images