Patent Application
20200264554
The present invention relates to a positioning apparatus that positions a draw-out portion with respect to an apparatus body and an image forming apparatus including the same.
Generally, in an image forming apparatus such as a printer, a copier, or a multifunctional apparatus, a photosensitive drum and a process unit that acts on the photosensitive drum are integrated as a cartridge, and a cartridge system in which this cartridge is attachable to and detachable from an apparatus body is employed.
Conventionally, in Japanese Patent Laid-Open No. 2007-178657, a color laser printer including a drum unit and a body casing to which the drum unit is attachable to and detachable from is proposed. The drum unit is a cartridge in which four drum subunits are supported by a pair of side plates. The body casing includes a standard shaft that a notch portion of the drum unit abuts to position the drum unit in an attached state. In addition, the notch portion of the drum unit is pressed against the standard shaft by being pressed toward the rear side of the apparatus by a pressing mechanism portion.
However, the notch portion of the drum unit described in Japanese Patent Laid-Open No. 2007-178657 abuts the standard shaft at two portions, which are an upper edge extending in the horizontal direction and a lower edge extending in the vertical direction. Therefore, a force of pressing the drum unit in the attachment direction does not act on the notch portion. Hence, the drum unit is pressed in the attachment direction by only the pressing mechanism portion, resulting in increase in the size and cost of the pressing mechanism portion.
According to one aspect of the present invention, a positioning apparatus includes an apparatus body, a draw-out portion configured to be drawn out from and attached to the apparatus body, and a positioning mechanism configured to position the draw-out portion at an attachment position with respect to the apparatus body, wherein the positioning mechanism includes a first engaging portion provided in one of the apparatus body and the draw-out portion, a first engaged portion provided in another of the apparatus body and the draw-out portion and configured to determine a position of the draw-out portion in an attachment direction by engaging with the first engaging portion, and wherein the first engaged portion includes an inclined surface that is inclined downward toward a downstream side in the attachment direction and causes a force in the attachment direction to act on the draw-out portion on a basis of a weight of the draw-out portion in a state in which the first engaged portion is engaged with the first engaging portion.
Further features of the present invention will become apparent from the following description of exemplary embodiments with reference to the attached drawings.
First, a printer 100 serving as an image forming apparatus according to a first exemplary embodiment is a full-color laser beam printer of an electrophotographic system. As illustrated in
In addition, the left side, the right side, the upper side, and the lower side are defined with a state in which the printer 100 is viewed from the front side as a standard. The left side and the right side will be also respectively referred to as the non-driving side and the driving side. Further, a direction from the right side toward the left side or from the left side toward the right side will be referred to as a left-right direction, and a direction from the upper side toward the lower side or from the lower side toward the upper side will be referred to as an up-down direction.
As illustrated in
The controller 200 controls an electrophotographic image formation process of the printer 100, and communicates various electric information with the external host apparatus 400. In addition, the controller 200 performs processing of electric information input from various process devices and sensors, processing of command signals to the various process devices, predetermined initial sequence control, sequence control of a predetermined image formation process, and so forth.
The sheet feeding portion 18 is provided in a lower portion of the printer 100, and includes a cassette 19 that accommodates the sheet S, an inner plate 21 that supports the sheet S and is capable of ascending and descending, a pickup roller 20a, and a separation roller pair 20b. The cassette 19 is formed to be capable of being drawn out to the front side from the apparatus body 100A and being attached to the apparatus body 100A from the front side. The sheet S supported on the inner plate 21 is fed by the pickup roller 20a. When a plurality of sheets S are fed at once, one sheet S is separated and fed by the separation roller pair 20b. To be noted, a torque limiter system or a retard roller system may be applied to the separation roller pair 20b, and a separation pad may be used instead of one of the separation roller pair 20b.
The fixing unit 23 includes a fixing film 23a configured to be heated by a heater, and a pressurizing roller 23b that is in pressure contact with the fixing film 23a, and a fixing nip Q is formed by the fixing film 23a and the pressurizing roller 23b. The discharge roller pair 24 includes a discharge driving roller 24a and a discharge driven roller 24b that is rotationally driven in accordance with the discharge driving roller 24a.
The image forming unit 10 serving as an image forming portion includes a cartridge tray 40, four process cartridges PPY, PPM, PPC, and PPK, a scanner unit 11, a transfer unit 12, and a cleaning unit 26. The process cartridges PPY, PPM, PPC, and PPK will be also collectively referred to as process cartridges PP. The transfer unit 12 includes a driving roller 14, an auxiliary roller 15, a tension roller 16, and an intermediate transfer belt 13. The intermediate transfer belt 13 is stretched over the driving roller 14, the auxiliary roller 15, and the tension roller 16, is formed from a dielectric material, and is flexible.
Primary transfer rollers 17Y, 17M, 17C, and 17K respectively opposing photosensitive drums of the process cartridges PPY, PPM, PPC, and PPK are provided in a space enclosed by the intermediate transfer belt 13. A secondary transfer roller 27 is provided opposite to the driving roller 14 with the intermediate transfer belt 13 interposed therebetween. A secondary transfer nip T2 is formed by the intermediate transfer belt 13 and the secondary transfer roller 27.
The four process cartridges PPY, PPM, PPC, and PPK respectively form toner images of four colors of yellow, magenta, cyan, and black. Y, M, C, and K respectively represent yellow, magenta, cyan, and black. To be noted, the four process cartridges PPY, PPM, PPC, and PPK have the same configuration except for the image to be formed. Therefore, only the configuration and image formation process of the process cartridge PPY will be described, and description of the process cartridges PPM, PPC, and PPK will be omitted.
As illustrated in
The process cartridges PPY, PPM, PPC, and PPK are held by the cartridge tray 40, and a user can access the cartridge tray 40 by opening the front door 31. Further, the user can replace the process cartridges PPY, PPM, PPC, and PPK by drawing out the cartridge tray 40 to the front side.
Next, an image forming operation of the printer 100 configured in this manner will be described. When the controller 200 of the printer 100 receives a job signal from the interface portion 300, an unillustrated developing separation mechanism provided in the apparatus body 100A moves in the front-rear direction. The developing separation mechanism causes the developing roller 3 to abut the photosensitive drum 1.
To be noted, in a job in which a monochromatic image is formed, only the photosensitive drum of the process cartridge PPK abuts the developing roller, and in a job in which a full-color image is formed, the photosensitive drums of the process cartridges PPY, PPM, PPC, and PPK abut respective developing rollers. Then, the photosensitive drums, the developing rollers, and the intermediate transfer belt 13 are driven by an unillustrated drive source.
The scanner unit 11 radiates laser light corresponding to an image signal onto the photosensitive drum 1 of the process cartridge PPY. In this case, the surface of the photosensitive drum 1 is uniformly charged to a predetermined polarity and predetermined potential in advance by a charging roller 5, and an electrostatic latent image is formed thereon as a result of being irradiated by the laser light from the scanner unit 11. The electrostatic latent image formed on the photosensitive drum 1 is developed by the developing roller 3, and thus a yellow toner image is formed on the photosensitive drum 1.
To be noted, a light guide 57 illustrated in
Similarly, the laser light is also radiated onto the photosensitive drums of the process cartridges PPM, PPC, and PPK from the scanner unit 11, and toner images of magenta, cyan, and black are formed on the respective photosensitive drums. The toner images of respective colors formed on the respective photosensitive drums are transferred onto the intermediate transfer belt 13 by primary transfer bias applied to the primary transfer rollers 17Y, 17M, 17C, and 17K. The full-color toner image transferred onto the intermediate transfer belt 13 is conveyed to the secondary transfer nip T2 by the intermediate transfer belt 13 rotated by the driving roller 14. To be noted, the image formation process of each color is performed at such a timing that each toner image is superimposed on an upstream toner image that has been already transferred onto the intermediate transfer belt 13 through primary transfer.
The skew of the sheet S fed out by the sheet feeding portion 18 is corrected by the registration roller pair 22 in parallel with this image formation process. Further, the registration roller pair 22 conveys the sheet S toward the secondary transfer roller 27 at a timing matching conveyance of the toner image on the intermediate transfer belt 13. The full-color toner image on the intermediate transfer belt 13 is transferred onto the sheet S at the secondary transfer nip T2 by a secondary transfer bias applied to the secondary transfer roller 27. In addition, after the transfer of the toner image, toner remaining on the surface of the intermediate transfer belt 13 is removed by the cleaning unit 26, and is collected into an unillustrated waste toner collection container.
The sheet S onto which the toner image has been transferred is subjected to predetermined heat and pressure in the fixing nip Q of the fixing unit 23, thus the toner melts and then adheres to the sheet S, and thereby an image is fixed to the sheet S. The sheet S having passed through the fixing unit 23 is discharged onto a discharge tray 25 by the discharge roller pair 24.
Next, a configuration of the cartridge tray 40 serving as a draw-out portion will be described. As illustrated in
The coupling members 42 to 46 are formed from a resin material, and are arranged in this order from the front side to the rear side. The light guide 57 described above is provided on each of the coupling members 42 to 45. The tray side plates 41L and 41R are formed from a metal material, the guide member 47L is supported by the tray side plate 41L, and the guide member 47R is supported by the tray side plate 41R. The guide members 47L and 47R are respectively slidable on a plurality of rollers 56L and 56R respectively provided on holders 52L and 52R illustrated in
The coupling member 42 includes receiving portions 42b and a grip portion 42d, and the user can draw out the cartridge tray 40 from the apparatus body 100A by gripping the grip portion 42d. In addition, when an impact toward the front side is applied to the printer 100 in a state in which the front door 31 is closed, the receiving portions 42b abut the front door 31 and thus suppress damage to components inside the printer 100. Similarly, the coupling member 46 include receiving portions 46a, and, when an impact toward the rear side is applied to the printer 100, the receiving portions 46a abut a fixing stay 35 illustrated in
The tray side plates 41L and 41R have shapes in which the upper portions thereof extend further to the outside than the lower portions thereof, and the distance between the tray side plates 41L and 41R in the left-right direction is smaller in the upper portion than in the lower portion. As a result of this, the width of the cartridge tray 40 in the left-right direction can be reduced without degrading the insertability/ejectability of the process cartridges PPY, PPM, PPC, and PPK, which contributes miniaturization of the printer 100.
Further, the lower side of the tray side plates 41L and 41R are bent into L shapes to secure the strength. Although the tray side plates 41L and 41R and the coupling members 42 to 46 are each fastened by screws, the configuration is not limited to this, and thermal caulking or the like may be used. In addition, a configuration in which only the coupling members 42 and 46 are fastened to the tray side plates 41L and 41R and the coupling members 43 to 45 are not fastened to the tray side plates 41L and 41R may be employed.
As illustrated in
Drum flanges 1a of the process cartridges PPY, PPM, PPC, and PPK illustrated in
In addition, boss portions 42aL, 43aL, 44aL, and 45aL are respectively formed on left end portions of the coupling members 42, 43, 44, and 45, and boss portions 42aR, 43aR, 44aR, and 45aR are respectively formed on right end portions of the coupling members 42, 43, 44, and 45. To be noted, the groove portions 1d are defined in left and right end portions of the process cartridge of each color as illustrated in
In this manner, the process cartridges PPY, PPM, PPC, and PPK are mounted on the cartridge tray 40, and are grounded via a wire material 48 serving as a drum ground wire provided in the guide member 47L.
Next, a positioning configuration of the cartridge tray 40 will be described. To be noted, the apparatus body 100A and the cartridge tray 40 constitute a positioning apparatus 140 illustrated in
The body side plates 36L and 36R respectively serving as a first support portion and a second support portion respectively include shaft support portions 50aL and 50aR on the rear side of the apparatus, and the shaft support portions 50aL and 50aR support a positioning shaft 50 serving as a first engaging portion and a shaft. To be noted, although the positioning shaft 50 is fixed so as to be immobile with respect to the shaft support portions 50aL and 50aR, the positioning shaft 50 may be rotatably supported as long as the positioning shaft 50 is immobile in the front-rear direction and in the up-down direction.
In addition, the body side plates 36L and 36R respectively have positioning grooves 36aL and 36aR on the apparatus front side. The positioning grooves 36aL and 36aR will be also collectively referred to as a body positioning portion 36a. As illustrated in
Further, a shaft contact portion 42c that supports an approximate center portion of the positioning shaft 49 in the axial direction thereof from below is formed on the coupling member 42, and the shaft contact portion 42c regulates downward warpage of the positioning shaft 49. To be noted, the shaft contact portion 42c may support a different position of the positioning shaft 49 from below instead of the approximate center portion of the positioning shaft 49 in the axial direction. However, it is preferable to regulate the downward warpage of the positioning shaft 49 at the center portion of the positioning shaft 49. In addition, the shaft contact portion 42c may be formed in a shape elongated in the axial direction.
As illustrated in
The fitting groove 37aR has a width equal to or slightly smaller than the outer diameter of the positioning shaft 49, and the end portion 49a of the positioning shaft 49 fits in the fitting groove 37aR when the cartridge tray 40 is positioned at an attached position. The guide groove 37bR has a width larger than the outer diameter of the positioning shaft 49, and guides the end portion 49a of the positioning shaft 49 to the fitting groove 37aR when attaching the cartridge tray 40 to the apparatus body 100A. To be noted, the guide groove and the fitting groove are also similarly defined in the body side plate 36L, and guide or engage with a left end portion of the positioning shaft 49.
As illustrated in
As illustrated in
As illustrated in
As illustrated in
Therefore, in the present exemplary embodiment, a rib 46b serving as a contact portion is formed in an approximate center portion of the coupling member 46 in the axial direction, that is, in the left-right direction. That is, the rib 46b is provided at a position between the body side plates 36L and 36R and between the positioning grooves 41bL and 41bR in the axial direction of the positioning shaft 50. The rib 46b abuts an approximate center portion of the positioning shaft 50 in the axial direction to support the positioning shaft 50 from below, and thus regulates downward warpage of the positioning shaft 50. To be noted, the rib 46b may support a different position of the positioning shaft 50 from below instead of the approximate center portion of the positioning shaft 50 in the axial direction. However, it is preferable to regulate the downward warpage of the positioning shaft 50 at the center portion of the positioning shaft 50. In addition, the rib 46b may be formed in a shape elongated in the axial direction, or a plurality of ribs 46b may be provided in the axial direction. In addition, although the downward warpage of the positioning shaft 50 is regulated by the rib 46b because the positioning shaft 50 receives a force in the gravity direction, the rib 46b does not have to contact the lower portion of the positioning shaft 50 as long as the member regulates the warpage of the positioning shaft 50 by receiving the force in the warping direction.
In addition, as illustrated in
Next, the draw-out operation and attachment operation of the cartridge tray 40 will be described. The product values of the process cartridges PPY, PPM, PPC, and PPK are lost when the developer is consumed to such a degree that it becomes impossible to form an image of a quality satisfactory the user that has purchased the process cartridges.
Therefore, an unillustrated detection portion that detects the amount of remaining developer of each process cartridge may be provided, and the detected amount of remaining developer may be compared by the controller 200 with a threshold value for cartridge lifetime notification or lifetime warning that is set in advance. In this case, when the detected amount of remaining developer of a process cartridge is smaller than the threshold value, a lifetime notification or lifetime warning is displayed for the process cartridge to prompt the user to replace the process cartridge. Then, the user opens the front door 31 of the printer 100, draws out the cartridge tray 40 to the outside of the apparatus, and replaces the process cartridge. The draw-out operation and attachment operation of the cartridge tray 40 will be described in detail below.
The front door 31 serving as a door member is supported so as to be openable and closeable with respect to the apparatus body 100A as illustrated in
When the user opens the front door 31, a plurality of unillustrated link members move in an interlocked manner via the door links 32L and 32R, and the transfer unit 12 rotates around the driving roller 14 by about 1°. As a result of this, the photosensitive drum 1 of each process cartridge is separated from the intermediate transfer belt 13 as illustrated in
Next, as illustrated in
Here, the tray pressing units 51 serving as first pressing units are respectively provided on the holders 52L and 52R respectively supported by the body side plates 36L and 36R, and press the cartridge tray 40 from the rear side to the front side during image formation. The tray pressing units 51 each include a tray pressing lever 53, a tray pressing link 54, and an urging spring 55 as illustrated in
As illustrated in
As illustrated in
Next, although motion of the surroundings of the positioning shafts 49 and 50 will be described with reference to
At the same time, the end portion 49a of the positioning shaft 49 of the cartridge tray 40 is released from the fitting groove 37aR of the positioning groove 36aR, and moves on to the guide groove 37bR. The cartridge tray 40 is drawn out in the draw-out direction Y2 while the end portion 49a of the positioning shaft 49 is guided by the guide groove 37bR.
When the cartridge tray 40 is drawn out to some extent, the guide members 47L and 47R of the cartridge tray 40 are guided on the rollers 56L and 56R as illustrated in
After the cartridge tray 40 is drawn out and a process cartridge is replaced, the cartridge tray 40 is attached to the apparatus body 100A. The attachment operation of attaching the cartridge tray 40 to the apparatus body 100A is the reverse of the draw-out operation. At this time, first, the sliding surface 46d starts sliding on the positioning shaft 50, and the end portion 49a of the positioning shaft 49 is passed onto the fitting groove 37aR from the guide groove 37bR after the positioning shaft 50 has passed the sliding surface 46d, as illustrated in
Since the boundary portion between the guide groove 37bR and the fitting groove 37aR has upward inclination and the end portion 49a of the positioning shaft 49 fits in the fitting groove 37aR, an operation force for the user to attach the cartridge tray 40 is large. However, since the positioning shaft 49 enters the fitting groove 37aR after the positioning shaft 50 has passed the sliding surface 46d, the timing when the operation force of the user increases does not concentrate, and therefore the operation force can be reduced. To be noted, the cartridge tray 40 is configured to be automatically pulled in to the attached position by a pull-in apparatus that will be described later when the cartridge tray 40 is inserted to a position at a predetermined distance from the attachment position on the front side.
When the cartridge tray 40 is inserted to the attached position and the front door 31 is closed, the tray pressing units 51 press the cartridge tray 40 to the rear side as illustrated in
As described above, in a state in which the front door 31 is closed and the printer 100 is capable of forming an image, the positioning shaft 50 engages with the positioning grooves 41bL and 41bR on the front side of the cartridge tray 40. At this time, since the positioning grooves 41bL and the 41bR are provided with the inclined surface 41f, the cartridge tray 40 is pulled in the attachment direction Y1 on the basis of the weight of the cartridge tray 40 and the downward force from the pressing units 33 and 34. As a result of this, the positioning surface 41e is pressed against the positioning shaft 50, and thus the cartridge tray 40 can be positioned in the attachment direction Y1 with a high precision.
In addition, the positioning shaft 49 engages with the positioning grooves 36aL and 36aR on the rear side of the cartridge tray 40. At this time, since the end portion 49a of the positioning shaft 49 fits in the fitting grooves of the positioning grooves 36aL and 36aR, rotation of the cartridge tray 40 in a direction perpendicular to the attachment direction Y1, that is, rotation of the cartridge tray 40 about the positioning shaft 50 can be restricted.
The positioning shaft 50 and the positioning grooves 36aL and 36aR that are provided in the apparatus body 100A and the positioning shaft 49 and the positioning grooves 41bL and 41bR that are provided in the cartridge tray 40 constitute a positioning mechanism 60 illustrated in
Further, since the positioning shaft 50 is supported from below by the rib 46b provided on the coupling member 46 of the cartridge tray 40, downward warpage, that is, deformation of the positioning shaft 50 is regulated. In addition, the locking portions 46c provided on the coupling member 46 reduce deformation of the cartridge tray 40 itself. Further, since the positioning shaft 49 on the rear side of the cartridge tray 40 is also supported from below by the shaft contact portion 42c, downward warpage of the positioning shaft 49 is regulated. According to such a configuration, the shaft diameter of the positioning shafts 49 and 50 can be reduced, the positioning shafts 49 and 50 can be formed from a cheaper resin material, and thus the cost and size can be reduced.
According to these, the cartridge tray 40 can be positioned at the attached position with high precision with respect to the apparatus body 100A, and the positioning precision of the cartridge tray 40 can be improved. Particularly, although the process cartridges held by the cartridge tray 40 are pressed from above by the pressing units 33 and 34 during image formation, this does not affect the positioning precision of the cartridge tray 40. Therefore, the positioning precision of each process cartridge held by the cartridge tray 40, specifically, the positioning precision between the photosensitive drum 1 and the intermediate transfer belt 13 is improved, and thus an image of high quality can be formed.
In addition, the cartridge tray 40 is urged to the front side at the attached position by the effect of the inclined surface 41f on the front side of the cartridge tray 40 and pressurization by the tray pressing units 51 on the rear side. Therefore, displacement of the cartridge tray 40 caused by vibration at the time of image formation or the like can be suppressed. In addition, by generating pressing force on the front side and rear side of the cartridge tray 40, the pressing force can be distributed, and thus the urging springs 55 of the tray pressing units 51 can be configured to have smaller elasticity. As a result of this, the size and cost of the tray pressing units 51 can be reduced.
To be noted, the positioning shaft 50 and the positioning grooves 41bL and 41bR that are included in the positioning mechanism 60 may be interchanged as long as the positioning shaft 50 is provided in one of the apparatus body 100A and the cartridge tray 40 and the positioning grooves 41bL and 41bR are provided in the other. In addition, the positioning shaft 49 and the positioning grooves 36aL and 36aR that are included in the positioning mechanism 60 may be interchanged as long as the positioning shaft 49 is provided in one of the apparatus body 100A and the cartridge tray 40 and the positioning grooves 36aL and 36aR are provided in the other.
In addition, the positioning shaft 49 does not have to be a penetrating shaft that extends in the entirety of the cartridge tray 40 in the left-right direction, and may be in any form as long as two projections projecting from the both sides of the cartridge tray 40 are formed.
In addition, although each process cartridge is formed by integrating the drum unit OP and the developing unit DP, these may be separately provided. Further, for example, a configuration in which the cartridge tray 40 only holds the drum unit OP and a configuration in which the cartridge tray 40 only holds the developing unit DP may be employed.
A pull-in apparatus 90 of the present exemplary embodiment will be described below. As illustrated in
The holder 91 is fixed to the fixing stay 35 of the apparatus body, and pivotably holds the arm 92 at a pivot support portion 91o. The arm 92 is always urged in a clockwise direction in
The urging force that the arm spring 93 applies to the arm 92 is adjusted in accordance with the total weight of the cartridge tray 40 including the process cartridges PP. In the configuration example to which the present exemplary embodiment is applied, a good operability can be obtained in the case where the urging force of the arm 92 is set to 2 kgf. This value is about 1 kgf to 1.5 kgf in terms of a force of pulling the cartridge tray 40 in the attachment direction. This is set to be smaller than force in the same direction generated by the tray pressing units 51 described above and by the contact between the inclined surface 41f and the positioning shaft 50. Meanwhile, the magnitude of the urging force of the arm spring 93 is set such that the cartridge tray 40 can be pulled in to the attached position against the frictional drag between the sliding surface 46d illustrated in
The arm 92 is capable of pivoting between the position of the stand-by state illustrated in
In the stand-by position, the arm 92 projects toward the front side of the image forming apparatus through an opening portion 35o illustrated in
As illustrated in
The locking member 94 and a locking spring 95 constitute a locking mechanism that locks the arm 92 in the stand-by position in the drawn-out state of the cartridge tray 40. In the description below, the position of the locking member 94 at which the abutting portion 941 faces the abutted portion 911 to restrict pivoting of the arm 92 will be referred to as a “locked position”, and the position of the locking member 94 at which the abutting portion 941 is separated from the abutted portion 911 to allow the pivoting of the arm 92 will be referred to as a “lock-release position”.
The locking member 94 is supported by the arm 92 so as to be pivotable about a pivot 92o, and is always urged in a counterclockwise direction in
As illustrated in
As a guide shape for guiding the second action portion 46s2 in the cartridge tray, inclined surfaces 92a1 and 92b1 of the arm upper portion 92a and the arm lower portion 92b are provided at an upstream end portion of the arm 92 in the attachment direction Y1 at the stand-by position. The inclined surfaces 92a1 and 92b1 are opposed to each other in the Z-axis direction, and are each inclined with respect to the X-Y plane such that the interval therebetween in the Z-axis direction is smaller on the more downstream side in the attachment direction Y1. In addition, the inclined surfaces 92a1 and 92b1 are formed in a region that overlaps with a position p1 in the X-axis direction where the second action portion 46s2 first abuts the locking member 94.
As illustrated in
An operation of the pull-in apparatus 90 will be described below with reference to
In the stand-by state illustrated in
In addition, in the stand-by state, although the locking member 94 is pressed in a counterclockwise direction r1 in
Then, as illustrated in
While the locking member 94 is pivoting from the locked position to the lock-release position, the arm 92 is kept in a state in which the arm 92 has been pivoted in the returning direction R2. In other words, the shape of the first engagement surface 92s is designed so as to secure such a pivot amount of the arm 92 that the locking member 94 can pivot to the lock-release position without interfering with the abutted portion 911. For example, this is satisfied in the case where the minimum distance from the pivot 92o of the locking member 94 to the abutted portion 911 is smaller than the pivoting radius of the abutting portion 941 about the pivot 92o during a period from the time when the second action portion 46s2 abuts the locking member 94 to the time when the abutting portion 941 is separated from the abutted portion 911.
As a result of the second action portion 46s2 moving the locking member 94 to the lock-release position, a state in which pivoting of the arm 92 in the pull-in direction R1 is not hindered by the locking member 94, that is, the lock-release state is taken. That is, if the cartridge tray 40 is vanished while maintaining the positions of the arm 92 and the locking member 94 of
The second engagement surface 92d of the arm 92 engages with the first action portion 46s1 in a state in which the locking of the arm 92 is released by the second action portion 46s2. When the second engagement surface 92d engages with the first action portion 46s1, the pull-in force in the attachment direction Y1 starts acting on the cartridge tray 40 from the arm 92 due to the urging force of the arm spring 93. In other words, the second engagement surface 92d starts abutting the first action portion 46s1 in a surface region of the arm 92 that abuts the first action portion 46s1 and in a direction whose normal vector includes a positive component in the Y-axis direction, in the course of inserting the cartridge tray 40.
As illustrated in
When drawing the cartridge tray 40 out of the apparatus body, the pull-in apparatus 90 changes from the pulled-in state illustrated in
When the cartridge tray 40 is drawn out further, the second action portion 46s2 is separated from the pressing portion 94s of the locking member 94. In addition, the first action portion 46s1 pivots the arm 92 in the returning direction R2 to a position beyond the stand-by position. Then, the arm 92 pivots in the pull-in direction R1 to the stand-by position while sliding on the first action portion 46s1 at the first engagement surface 92s, thus the abutting portion 941 of the locking member 94 abuts the abutted portion 911 of the holder 91, and the pull-in apparatus 90 takes the stand-by state illustrated in
The pull-in apparatus 90 of the present exemplary embodiment, having a configuration in which the pivoting of the arm 92 is locked in the stand-by state, requires two actions of (1) pivoting of the arm 92 in the returning direction R2 and (2) pivoting of the locking member 94. That is, in the case where (1) and (2) described above do not act on the pull-in apparatus 90 in this order, normally the locking of the arm 92 is not released. As a result of this, in the stand-by state as illustrated in
Further, in the configuration of the present exemplary embodiment, the locking member 94 is held in a gap between two portions of the arm 92, and this gap needs to be accessed to move the locking member 94. If it is attempted to release the locking by one action of moving the locking member 94 to the lock-release position in the state in which the arm 92 is in the stand-by position, the locking member 94 needs to be strongly pressed in an arrow direction of
Therefore, according to the configuration of the present exemplary embodiment in which the locking member 94 is surrounded and protected by the arm 92, the stability of the pull-in apparatus 90 can be further improved. To be noted, in the present exemplary embodiment, the second action portion 46s2 is used as a second abutting portion, and the possibility of an object other than the second action portion 46s2 getting into the gap of the arm 92 is reduced by setting the thickness of the second action portion 46s2 to be smaller than the interval z1 of the arm 92. Even in the case of using a second abutting portion not having a plate-like shape instead of this, an effect similar to that of the present exemplary embodiment can be obtained by disposing the second abutting portion between a plurality of parts of the arm member.
In addition, in the pull-in apparatus 90 of the present exemplary embodiment, at least the arm spring 93 and the pivot support portion 910 of the arm 92 are disposed further on the rear side than the front side wall surface 35a of the fixing stay 35 illustrated in
In addition, in the configuration of the present exemplary embodiment, the arm spring 93 urges the arm 92 in the pull-in direction R1 in the entire region from the stand-by position to the pulled-in position. Therefore, compared with a configuration used for a pull-in apparatus of a so-called toggle type in which the urging direction of the arm by the spring member changes within the range from the stand-by position to the pulled-in position, the distance to which the arm 92 is capable of pulling in the cartridge tray 40 can be set to be long. In the case of the pull-in apparatus of a toggle type, the pull-in action occurs after the arm passes a middle position. The pull-in action is weak near the middle position, and rather a force in a direction of pushing back the cartridge tray is applied before passing the middle position. In contrast, in the case of the present exemplary embodiment, the urging force of the arm spring 93 is efficiently transmitted as a force of moving the cartridge tray 40 in the attachment direction Y1 at the stage of
In addition, the present exemplary embodiment also has a good space-saving characteristic. In the state illustrated in
To be noted, the pull-in apparatus 90 of the present exemplary embodiment has a configuration in which the force the cartridge tray 40 receives from the arm 92 in the course of the lock-release operation and the pull-in operation includes a component toward one side in the X-axis direction, which is the left side in
Here, in the present exemplary embodiment, positioning of a photosensitive drum in the longitudinal direction in the case of performing an image forming operation after attaching the cartridge tray 40 to the apparatus body is performed by pressing the photosensitive drum leftward. Specifically, a driving coupling provided in the apparatus body presses the drum coupling 1c illustrated in
In such a configuration, the pull-in apparatus 90 of the present exemplary embodiment is provided such that the direction of a component force applied to the cartridge tray 40 in a direction perpendicular to the attachment direction in the course of the pull-in operation coincides with the direction in which the photosensitive drum is pressed in the longitudinal direction in a state after the tray is attached. If these are opposite to each other, a guide shape that regulates the position of the cartridge tray 40 in the left-right direction at the time of inserting the cartridge tray 40 and another guide shape that receives a force that the cartridge tray 40 receives via the photosensitive drum after being attached and regulates the position of the cartridge tray 40 need to be provided separately. For example, the guide shape is a side wall that opposes the guide member 47L of the cartridge tray 40 in the left-right direction. In contrast, in the present exemplary embodiment, the directions of these forces coincide with each other, and therefore the position regulating function at the time of inserting the cartridge tray 40 and the position regulating function after the attachment can be realized by the same guide shape, and thus the configuration of the apparatus can be simplified.
In addition, as illustrated in
The contact t1 and the wire spring t2 are provided in a left end portion of the cartridge tray 40, and are not provided on the right side thereof. In such a configuration, the position at which the arm 92 presses the first action portion 46s1 in the attachment direction of the cartridge tray 40 in the attached state of the cartridge tray 40 is offset to the left side with respect to the center position of the cartridge tray 40 in the X-axis direction. Therefore, a force of the wire spring t2 pressing the cartridge tray 40 via the contact t1 and a force that the cartridge tray 40 receives from the pull-in apparatus 90 cancel each other, and thus inclination of the cartridge tray 40 is suppressed.
Further, as described above, the process cartridges PPY, PPM, PPC, and PPK are positioned not with respect to the apparatus body of the image forming apparatus but with respect to the cartridge tray 40. In such a case, the precision of the positioning may be degraded if the user is let perform the final positioning of the cartridge tray 40 by an insertion operation. In the case where the positioning precision of the cartridge tray 40 with respect to the body is low, the laser light irradiation position on the surface of the photosensitive drum 1 is displaced from an ideal position, resulting in displacement of an image position on the sheet. In contrast, according to the exemplary embodiment described above, since the positioning of the cartridge tray 40 with respect to the body is performed by the urging force of the arm spring 93 and the like, such a problem can be suppressed.
In the present exemplary embodiment, as illustrated in
In addition, the first engagement surface 92s of the arm 92 preferably has a shape that reduces fluctuation of the operational load of inserting the cartridge tray 40 to a position where pulling in of the cartridge tray 40 is started. For example, it is preferable that the first engagement surface 92s has an arcuate shape centered in a position away from the pivot support portion 910 of the arm 92 by a certain distance as viewed in the Z-axis direction. In addition, although all the components other than the springs 93 and 95 are formed from a resin material in the present exemplary embodiment, it can be also considered to form components that receive strong force, such as the arm 92, from a metal material. In addition, it can be also considered to use torsion coil springs or compressive springs for the springs instead of tension springs.
In addition, a pull-in operation similar to that of the present exemplary embodiment can be realized also in the case where the arm 92 and the locking member 94 are disposed in the cartridge tray 40 and the first action portion 46s1 and the second action portion 46s2 are disposed in the apparatus body. That is, the arm member and the restriction member may be disposed in one of the apparatus body and the unit, and the first abutting portion and the second abutting portion may be disposed in the other of the apparatus body and the unit. However, disposing the arm 92 and the locking member 94 that are movable members in the apparatus body as in the present exemplary embodiment is advantageous for reducing the weight and size of the cartridge tray 40 and suppress damage to the members.
A pull-in apparatus according to a second exemplary embodiment will be described. In the first exemplary embodiment, since only one arm 92 is provided, the cartridge tray 40 is pressed leftward or rightward by the arm 92 when inserting the cartridge tray 40 in the apparatus body, which is a cause of generation of a frictional force between the apparatus body and the cartridge tray 40.
In the present exemplary embodiment, two arms 92L and 92R are symmetrically arranged in the left-right direction as illustrated in
In the present exemplary embodiment, detailed configurations of the arms 92L and 92R and the locking members 94L and 94R and operations of the arms 92L and 92R and the locking members 94L and 94R at the time of inserting the cartridge tray are the same as those of the arm 92 and the locking member 94 of the first exemplary embodiment. Therefore, also according to the configuration of the present exemplary embodiment, a pull-in apparatus capable of suppressing erroneous release of the locking can be provided.
In addition, in the configuration of the present exemplary embodiment, in forces that the two arms 92L and 92R apply to two first action portions 46s1, components in the X-axis direction perpendicular to the attachment direction of the cartridge tray 40 cancel each other. As a result of this, friction between the cartridge tray 40 and the apparatus body can be reduced, and thus the operational load can be reduced. In addition, inclination of the cartridge tray 40 as viewed from above caused by the force received from the pull-in apparatus 90 during the inserting operation can be suppressed. Further, in the case where the same spring member as in the first exemplary embodiment is used as the arm spring 93, since the tension of the arm spring 93 acts on the cartridge tray 40 through the arms 92L and 92R respectively connected to the two ends of the arm spring 93, the force in the attachment direction received by the tray is approximately doubled. As a result, the required pull-in force can be secured even in the case where a spring member weaker than in the first exemplary embodiment is used, and therefore the cost of the arm spring 93 can be reduced.
A pull-in apparatus according to a third exemplary embodiment will be described. Whereas the arm 92 holds the locking member 94 in the first exemplary embodiment, in the present exemplary embodiment a locking member 94A is pivotably supported by the holder 91 as illustrated in
In the stand-by state, an engagement portion 92e of the arm 92 abuts the locking member 94A, and thus pivoting of the arm 92 in the pull-in direction R1 is restricted. When the cartridge tray 40 is inserted, the first action portion 46s1 provided on the tray presses the first engagement surface 92s of the arm 92 to pivot the arm 92 in the returning direction R2 from the stand-by position against the arm spring 93 as illustrated in
When the cartridge tray 40 is further inserted, the second action portion 46s2 abuts the locking member 94A to pivot the locking member 94A in the clockwise direction in
Also in the present exemplary embodiment, two actions of (1) pivoting of the arm 92 in the returning direction R2 and (2) pivoting of the locking member 94A are required for releasing the locking of the arm 92. Therefore, also according to the configuration of the present exemplary embodiment, a pull-in apparatus capable of suppressing erroneous release of locking can be provided.
Although the pull-in apparatus 90 that pulls the cartridge tray 40 into the apparatus body has been described in the first to third exemplary embodiments above, this pull-in apparatus 90 is applicable to an arbitrary apparatus including a unit that can be drawn out of the apparatus body. For example, this can be applied to a configuration in which the cassette 19 illustrated in
In addition, for example, this can be applied to a configuration in which a sheet processing apparatus or an option feeder attachable to and detachable from the apparatus body of an image forming apparatus is pulled into the apparatus body. The sheet processing apparatus is an apparatus that performs processing such as binding on sheets, and the option feeder is an apparatus that supplies a sheet to the apparatus body. In addition, the apparatus to which the pull-in apparatus is applicable is not limited to an image forming apparatus, and the pull-in apparatus is also applicable to, for example, a configuration in which a drawer of a desk for an office or a drawer of storage furniture is pulled into the apparatus body, that is, a casing.
In addition, although description has been given by using the printer 100 of an electrophotographic system in all of the embodiments described above, the present invention is not limited to this. For example, the present invention can be also applied to an image forming apparatus of an inkjet system that forms an image on a sheet by ejecting an ink liquid through a nozzle.
While the present invention has been described with reference to exemplary embodiments, it is to be understood that the invention is not limited to the disclosed exemplary embodiments. The scope of the following claims is to be accorded the broadest interpretation so as to encompass all such modifications and equivalent structures and functions.
This application claims the benefit of Japanese Patent Application No. 2019-027865, filed Feb. 19, 2019, and Japanese Patent Application No. 2019-027866, filed Feb. 19, 2019, which are hereby incorporated by reference herein in their entirety.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2019-027865 | Feb 2019 | JP | national |
| 2019-027866 | Feb 2019 | JP | national |
