JP4018697B2 - Electrophotographic image forming apparatus - Google Patents

Description

  The present invention relates to an electrophotographic image forming apparatus to which a process cartridge can be attached and detached.

  Here, an electrophotographic image forming apparatus (hereinafter referred to as an image forming apparatus) forms an image on a recording medium (for example, recording paper, an OHP sheet, etc.) using an electrophotographic image forming system. Examples of the image forming apparatus include, for example, an electrophotographic copying machine, an electrophotographic printer (for example, a laser printer, an LED printer, etc.), a facsimile apparatus, a word processor, and a complex machine (multifunction printer, etc.) thereof.

  Further, the process cartridge is a cartridge in which at least one of charging means, developing means, and cleaning means as process means and an electrophotographic photosensitive member (hereinafter referred to as an electrophotographic photosensitive drum) are integrally formed. It can be attached to and detached from the electrophotographic image forming apparatus main body. Therefore, the process cartridge includes a cartridge in which at least the developing means as the process means and the electrophotographic photosensitive drum are integrally formed into a cartridge that can be attached to and detached from the main body of the electrophotographic image forming apparatus.

  The process means acts on the electrophotographic photosensitive drum and means at least one of a charging means, a developing means, and a cleaning means.

  In the image forming apparatus, the electrophotographic photosensitive drum and the process means acting on the photosensitive drum are integrally formed into a cartridge. A process cartridge system is employed in which the cartridge is detachable from the image forming apparatus main body. According to this process cartridge system, maintenance of the image forming apparatus can be performed by the user himself / herself without depending on the service person. Therefore, the operability of the image forming apparatus can be remarkably improved. Therefore, this process cartridge system is widely used in image forming apparatuses.

  The cartridge has an opening for exposing the photosensitive drum to the cartridge frame. When the cartridge is not used, the electrophotographic photosensitive drum is protected by closing the opening with a protective member.

  When the user uses the cartridge, the protective member is retracted from the opening in conjunction with the operation of the user inserting the cartridge into the image forming apparatus main body. As a result, the photosensitive drum is exposed from the opening.

  Retraction of the protective member is performed in conjunction with the operation of the user inserting the cartridge as disclosed in Patent Document 1.

  More specifically, an interlocking member (link member) that rotates in conjunction with the protective member (shutter member) is brought into contact with the inclined surface of the guide rail fixed to the image forming apparatus main body. The protective member is moved to the retracted position in conjunction with the insertion of the cartridge into the image forming apparatus main body.

Patent Document 2 describes a protective member opening / closing mechanism described below. First, when the back surface of the pressing unit of the image forming apparatus main body is opened, the movable body moves out of the apparatus main body. Next, when the cartridge is inserted into the movable body, the operating arm of the cartridge comes into contact with the cam receiving surface of the movable body. As a result, the protective member (shutter cover) starts to move to the retracted position. Next, when the movable body is inserted into the apparatus main body, the cam receiving rib provided in the apparatus main body and the operating arm come into contact with each other to complete the opening of the protective member.
JP-A-8-305243 (page 8-12, FIGS. 7-12) Japanese Patent Laid-Open No. 2000-132061 (paragraphs 0095-0109, FIGS. 44-54)

  The present invention is a further development of the above-described conventional technique.

  An object of the present invention is to provide a protective member that covers and protects an exposed portion of the electrophotographic photosensitive drum exposed from the cartridge frame, and a protective position that covers the exposed portion and an exposure that exposes the exposed portion by retreating from the protective position. It is to achieve downsizing of the main body of the image forming apparatus by reducing the occupied space in the main body of the image forming apparatus necessary for moving between the positions.

A typical configuration of the electrophotographic image forming apparatus according to the present invention for achieving the above object is as follows:
An electrophotographic photosensitive drum;
Process means acting on the electrophotographic photosensitive drum;
A cartridge frame for supporting the electrophotographic photosensitive drum and the process means;
A protective member that covers and protects the exposed portion of the electrophotographic photosensitive drum exposed from the cartridge frame, and a protection position that covers the exposed portion and retreats from the protection position to expose the exposed portion. A protective member movable between the exposed positions;
An interlocking member that interlocks with the protective member;
In an electrophotographic image forming apparatus that can attach and detach a process cartridge having an image on a recording medium,
An opening through which the process cartridge passes when the process cartridge is inserted into the apparatus main body of the electrophotographic image forming apparatus, and through which the process cartridge passes when the process cartridge is taken out of the apparatus main body;
An open / close cover that is movable with respect to the apparatus main body and can take a closed position for closing the opening and an open position for opening the opening;
In conjunction with the opening / closing cover moving from the closed position to the open position, at least a portion is positioned outward from the opening, and the opening / closing cover is interlocked to move from the open position to the closed position. A movable member positioned in the apparatus main body, wherein the protective member is moved from the closed position toward the upstream side in the insertion direction in conjunction with an insertion operation of inserting the process cartridge into the apparatus main body from the closed position to the open position. A movable member that contacts a part of the interlocking member when the process cartridge is inserted into the apparatus main body,
A main body guide that is fixedly provided in the apparatus main body and guides the process cartridge in a mounting direction by contacting a guided portion of the process cartridge when the process cartridge is inserted into the apparatus main body. The movable member is inserted when the process cartridge is inserted into the apparatus main body in order to further move the protective member from the closed position to the open position toward the upstream side in the insertion direction in conjunction with the insertion operation. A body guide that contacts a part of the interlocking member that has passed through
I have a,
In the process of inserting the process cartridge into the apparatus main body, the main body guide is arranged in a direction perpendicular to the insertion direction so that a part of the interlocking member moves smoothly from passing through the movable member to the main body guide. Has a portion overlapping the movable member .

  According to the present invention, a part of the interlocking member comes into contact with a portion located outside the movable member at least partly located outside from the opening in conjunction with the opening / closing cover moving from the closed position to the open position. As a result, the protective member can be moved from the closed position to the open position toward the upstream side in the insertion direction, so that the area occupied by the protective member in the image forming apparatus can be reduced.

  As a result, the image forming apparatus main body can be downsized.

  Further, according to the present invention, the main body guide portion has a guide function when the cartridge is inserted into the apparatus main body and a function of moving the interlocking member to open the protective member, thereby reducing cost and image formation. Miniaturization of the device body can be realized.

  FIG. 1 is a cross-sectional view of an image forming apparatus main body 1 (hereinafter referred to as an apparatus main body) and a process cartridge 2 constituting an image forming apparatus according to an embodiment to which the present invention is applied. FIG. 2 is a sectional view of a process cartridge 2 according to an embodiment to which the present invention is applied, and FIG. 3 is a sectional view of a developing device unit 40 according to the embodiment to which the present invention is applied.

  Hereinafter, the image forming apparatus will be described with reference to FIGS.

(overall structure)
This image forming apparatus is a laser printer using an electrophotographic technique in which a process cartridge (hereinafter referred to as a cartridge) 2 is detachable from an apparatus main body 1. When the cartridge 2 is mounted on the apparatus main body 1, an exposure device (laser scanner unit) 3 is disposed above the cartridge 2. A sheet tray 4 containing a recording medium (hereinafter referred to as a sheet material) P that is an image forming target is disposed below the cartridge 2. Further, the apparatus main body 1 includes a pickup roller 5a (115), a feeding roller 5b, a conveyance roller pair 5c, a transfer guide 6, a charging roller 7 for performing transfer, and a conveyance along the conveyance direction of the sheet material P. A guide 8, a fixing device 9, a discharge roller pair 10, a discharge tray 11, and the like are arranged.

(Description of image forming process)
Next, an outline of the image forming process will be described. Based on the print start signal, the electrophotographic photosensitive drum (hereinafter referred to as photosensitive drum) 20 is rotationally driven in the direction of arrow R1 with a predetermined peripheral speed (process speed). A charging roller 12 to which a bias voltage is applied is in contact with the outer peripheral surface of the photosensitive drum 20. The charging roller 12 charges the outer peripheral surface of the photosensitive drum 20 uniformly and uniformly.

  The scanner unit 3 outputs laser light L modulated in accordance with the time-series electric digital pixel signal of image information. The laser light L enters the inside of the cartridge 2 from the exposure window 53 on the upper surface of the cartridge 2 and scans and exposes the outer peripheral surface of the photosensitive drum 20. As a result, an electrostatic latent image corresponding to the image information is formed on the outer peripheral surface of the photosensitive drum 20. This latent image is developed by a developer (hereinafter referred to as toner) of the developing device unit 40. That is, it is visualized as a toner image.

More specifically, the charging roller (charging means as process means) 12 is provided in contact with the photosensitive drum 20 and charges the photosensitive drum 20. The charging roller 12 is driven to rotate by the photosensitive drum 20. Further, the developing device unit 40 supplies toner to the developing area of the photosensitive drum 20 to develop the latent image formed on the photosensitive drum 20.

The developing device unit 40 sends the toner T in the toner chamber 45 to the toner supply chamber 44 by the rotation of the stirring member 43. Then, the developing roller 41, which is a developer carrying member including a magnet roller (fixed magnet) 41a, is rotated, and the toner layer to which the triboelectric charge is applied by the developing blade 42 is developed to the developing roller (developing means as a process means) 41. Form on the surface. Then, a toner image is formed and developed by transferring the toner to the photosensitive drum 20 in accordance with the latent image.

  The developing blade 42 defines the amount of toner on the peripheral surface of the developing roller 41 and imparts triboelectric charge.

On the other hand, the sheet material P stored in the lower part of the apparatus main body 1 is fed from the tray 4 by the roller 5a, the roller 5b, and the roller pair 5c at the timing when the laser beam L is output. Then, the sheet material P is supplied to the transfer position between the photosensitive drum 20 and the transfer charging roller 7 via the transfer guide 6 at a timing. In this transfer position, the toner image are sequentially transferred from the photosensitive drum 20 to the sheet material P.

The sheet material P to which the toner image has been transferred is separated from the photosensitive drum 20 and conveyed to the fixing device 9 along the conveyance guide 8. The sheet material P passes through the nip portion between the fixing roller 9a and the pressure roller 9b constituting the fixing device 9. A pressure / heat fixing process is performed at the nip portion, and the toner image is fixed to the sheet material P. The sheet material P that has undergone the toner image fixing process is conveyed to the discharge roller pair 10 and discharged to the discharge tray 11.

  On the other hand, residual toner on the outer peripheral surface of the photosensitive drum 20 after transfer is removed by a cleaning blade (cleaning means as a process means) 52. The photosensitive drum 20 is again subjected to image formation starting from charging.

  The apparatus main body 1 can also feed paper from a manual sheet tray 111a. The tray 111a is formed of a part of the opening / closing cover 111 and can be used by rotating around the rotation shaft 110.

The sheet material P placed on the tray 111a is fed from the pickup roller 115. Thereafter, the sheet is discharged onto the discharge tray 11 through the transfer guide 6, the photosensitive drum 20, the transfer charging roller 7, the fixing device 9, and the discharge roller pair 10.

(Process cartridge frame structure)
Next, the frame structure of the cartridge 2 according to an embodiment to which the present invention is applied will be described.

  As shown in FIG. 2, the photosensitive drum 20, the charging roller 12, and the cleaning blade 52 are attached to a drum frame (cartridge frame) 51 and constitute an integral photosensitive unit 50.

  On the other hand, the developing device unit 40 includes a toner storage container 40 a that stores toner, a lid 40 b, and a developing frame (cartridge frame) 40 c that holds the developing roller 41 and the developing blade 42. The toner storage container 40a and the developing device frame 40c are integrally joined together by means such as welding of outer peripheral flange portions 40d and 40e. The cartridge frame is at least a frame that supports the photosensitive drum 20 and constitutes the cartridge 2 or a frame that constitutes a part thereof. In this embodiment, a drum frame 51 and a developing frame 40c are provided. However, the members supported by the cartridge frame are not limited to the members described above except for the photosensitive drum 20, and can be selected as appropriate.

  Then, the process cartridge 2 is configured by connecting the unit 50 and the unit 40 so as to be rotatable with each other by a connecting member 54 of a round pin.

  That is, as shown in FIG. 3, a round rotation hole 40f is provided in parallel with the developing roller 41 at the tip of the arm portion provided on both sides in the longitudinal direction (the axial direction of the developing roller 41) of the developing frame 40c. is there.

  When the coupling arm 48 is inserted into a predetermined position of the drum frame 51, the drum frame 51 has a fitting hole 51a for fitting the coupling member 54 coaxially with the rotation hole 40f (see FIG. 4a). .

By co-inserting the coupling member 54 into the rotation hole 40f and the fitting hole 51a, the photosensitive unit 50 and the developing device unit 40 are coupled so as to be rotatable around the coupling member 54. At this time, the compression coil spring 46 attached to the base of the coupling arm 48 hits the drum frame 51 and elastically biases the developing device unit 40 downward. Thereby, the developing roller 41 is reliably pressed toward the photosensitive drum 20.

  An interval holding member (not shown) is attached to both ends of the developing roller 41, and the developing roller 41 is held at a predetermined interval from the photosensitive drum 20.

(Photosensitive drum protection member)
The protection member 101 of the photosensitive drum 20 will be described.

  FIG. 4A is an external perspective view illustrating a state where the protection member 101 is in the protection position.

  FIG. 4B is an external perspective view illustrating a state where the protection member 101 is in the retracted position.

  A part of the photosensitive drum 20 is exposed from the drum frame 51 under the photosensitive drum 20 so that the photosensitive drum 20 can come into contact with the sheet material P.

When unused cartridge 2, to protect the photosensitive drum 20 by obscuring exposed portion 20a of the photosensitive drum 20 with a protective member 101 (FIG. 4a).

Further, when the cartridge 2 is used, the lower portion of the photosensitive drum 20 is exposed by retreating from the protection position (FIG. 4b). That is, the protection member 101 covers and protects the exposed portion of the photosensitive drum 20 exposed from the cartridge frame, and the protection member 101 retracts from the protection position that covers the exposed portion and the protection position. It is possible to move between exposure positions that expose exposed portions.

  As shown in FIGS. 4a, 4b, and 4c, the protective member 101 includes an arm 102 that is rotatable about a shaft 40g provided on one of the longitudinal outer surfaces of the developing frame 40c, and a developing frame. It is rotatably supported by an interlocking member 103 that can rotate about a rotation center 55a provided on a side cover 55 attached to both outer sides in the longitudinal direction of 40c.

  The arm 102 and the interlocking member 103 rotate in conjunction with each other when the protection member 101 moves between the protection position and the retracted position (FIGS. 4a and 4c). That is, the interlocking member 103 is interlocked with the protective member 101.

When the user inserts the cartridge 2, the protective member 101 is opened from the protection position to the retracted position by abutting the protruding portion (a part of the interlocking member) 103 a of the interlocking member 103 with the apparatus main body 1 ( FIG. 4b). Conversely, when the user removes the cartridge 2 from the apparatus main body 1, the protection member 101 is automatically closed by the elastic force (bias) of a torsion coil spring (not shown) attached near the shaft 40 g of the arm 102.

  Note that the protrusions 103a are disposed at one end and the other end of the cartridge 2 (cartridge frame) in the longitudinal direction.

(Explanation of process cartridge attachment / detachment)
Next, a configuration for attaching and detaching the cartridge 2 to and from the apparatus main body 1 will be described.

  FIGS. 5a, 5b, and 5c are explanatory views showing a state in which the process cartridge is attached and detached.

  FIG. 6A is an explanatory diagram of the right side guide structure for guiding the attachment and detachment of the process cartridge.

  FIG. 6B is an explanatory diagram of a left guide structure for guiding the attachment and detachment of the process cartridge.

  FIG. 7 a is a partial view illustrating the state of the apparatus main body when the opening / closing cover is closed.

  FIG. 7B is a partial view for explaining the state of the apparatus main body when the opening / closing cover is closed.

  FIG. 7 c illustrates the cover 119.

  FIG. 7 d is a configuration explanatory view for explaining the operation of the cover 119.

  FIG. 7E is an explanatory diagram of the process cartridge insertion state for explaining the role of the cover 119.

  FIG. 7 f is a partial explanatory view of the process cartridge insertion state for explaining the role of the cover 119.

  8a and 8b are explanatory diagrams of the state of the process cartridge 2 in the initial insertion 1 state.

  FIGS. 9A and 9B are explanatory views of the state 2 of the process cartridge 2 in the initial insertion stage.

  10a and 10b are explanatory views of the state of the process cartridge 2 in the middle period 1 of insertion.

  FIGS. 11 a and 11 b are explanatory views of the state of the process cartridge 2 in the middle insertion period 2.

12a and 12b are explanatory diagrams of the process cartridge 2 being inserted.

  Hereinafter, the minimum necessary components are used in the drawings used for the description.

  As shown in FIGS. 5 a, 5 b, and 5 c, the cartridge 2 is detachably mounted on the cartridge mounting means provided on the apparatus body 1 by the user by opening the opening / closing cover 111 of the apparatus body 1.

The opening / closing cover 111 is disposed so as to cover the inside of the apparatus main body 1 (FIG. 5a). The opening / closing cover 111 is attached to the apparatus body 1 so as to be freely opened and closed. The opening / closing cover 111 is opened forward and downward as viewed from the user around the opening / closing shaft 112 (see FIG. 1). Then, the cartridge 2 can pass when the cartridge 2 is inserted into the apparatus body 1 ( inside the apparatus body) , and the cartridge 2 can pass when the cartridge 2 is taken out of the apparatus body 1 (outside the apparatus body) . An opening 113 having a size is provided in the apparatus main body 1 (FIG. 5b). In FIG. 5b, the outline when the open / close cover 111 is closed is indicated by a dotted line. From this dotted line, the inside of the apparatus is the opening 113.

  Next, the cartridge 2 is mounted to a predetermined position along the cartridge 2 mounting means provided in the apparatus main body 1 shown below (FIG. 5c).

  Rotating shafts 120R1 and 120L1 are provided on the movable member right 120R and the movable member left 120L, respectively. The movable member right 120 </ b> R and the movable member left 120 </ b> L are rotatably supported on the apparatus main body 1 by bearings (not shown) of the apparatus main body 1 (FIGS. 7 a and 7 b).

Further, the link member left 152L is rotatably attached to the opening / closing cover 111 and the movable member left 120L. Similarly, a link member right (not shown) is attached to the opening / closing cover 111 and the movable member right 120R (FIG. 6a).

  By the link member right and link member left 152L, the movable members 120R and 120L rotate in conjunction with the opening / closing operation of the opening / closing cover 111.

  Further, a manual feed tray 111a, a conveyance guide 151 serving as a guide for conveying the sheet material P fed from the sheet tray 4, and a manual feed pickup roller 115 unit 153 include a movable member right 120R. The movable member left 120L is supported so as to be integrally fixed and rotatable. And according to rotation operation of movable member right 120R and movable member left 120L, conveyance guide 151 also rotates centering on rotating shafts 120R1 and 120L1.

  Cover 119 is shown in FIG. The cover 119 is provided with a protrusion 119a that engages with an elongated guide hole 130R6 (FIG. 7d) provided in the guide member right 130R, and a shaft 119b that engages with the round hole 120R2 (FIG. 7d) of the movable member right 120R. Yes. The shaft 119b is rotatably held in the hole 120R2, and the protrusion 119a is movable along the guide 130R6.

When the movable member right 120R rotates, the cover 119 rotates around the shaft 119b, and the protrusion 119a moves while sliding in the hole 130R6.

  The cover 119 plays two roles. One is that the cover 119 is arranged so as to cover the drive gear 118 with the open / close cover 111 open, in order to prevent the user from touching the drive gear 118 (FIG. 6a). The other is the role of covering the space below the guide right 130R so that the protrusion 103a of the interlocking member 103 does not get caught under the guide right 130R when the user inserts the cartridge 2 diagonally ( FIG. 7e, FIG. 7f).

The drive gear 118 is a gear that drives the manual pickup roller 115. In FIG. 6b , the gear 115a at the right end of the shaft of the pickup roller 115 is engaged with the drive gear 118 when the open / close cover 111 is closed.

  The user opens the opening / closing cover 111. Then, in conjunction with the opening operation of the cover 111, the movable member right 120R, the movable member left 120L, the conveyance guide 151, the manual feed pickup roller unit 153, the cover 119, the link member left 152L, and the link member right ( Rotates (not shown).

  Then, the movable member right 120R and the movable member left 120L move from the inside of the apparatus main body 1 (opening 113) to the outside of the apparatus main body 1 (FIGS. 6a and 6b).

  From this state, the user closes the opening / closing cover 111. Then, in conjunction with the closing operation of the cover 111, the movable member right 120R, the movable member left 120L, the conveyance guide 151, the manual feed pickup roller unit 153, the cover 119, the link member left 152L, and the link member right Rotate). And these are stored in the inside (opening 113) of the apparatus main body 1 (FIG. 7a, FIG. 7b, the opening / closing cover 111 is not shown).

  The cartridge mounting means of the present embodiment has main body guide portions 130L1, 130L2, 130R1, and 130R2 provided on the apparatus main body 1, as shown in FIGS. 6a and 6b. The main body guide portions 130L1, 130L2, 130R1, and 130R2 are fixed to the apparatus main body 1 using a fixing member such as a screw.

  When the cartridge 2 is attached to the apparatus main body 1, the cylindrical portions (guided portions) 140R1, 140R2, 140L1, and 140L2 (FIG. 4) on both outer side surfaces of the cartridge 2 are respectively provided to the main body guide portions 130R1 provided in the apparatus main body 1. , 130R2, 130L1, and 130L2. That is, the main body guide portions 130R1, 130R2, 130L1, and 130L2 come into contact with the cylindrical portions (guided portions) 140R1, 140R2, 140L1, and 140L2 when the cartridge 2 is inserted into the apparatus main body 1. The cartridge 2 is guided in the mounting direction.

  The cylindrical portions (guided portions) 140R1 and 140R2 are arranged on one end side in the longitudinal direction of the cartridge 2, that is, on one end side in the longitudinal direction of the drum frame (cartridge frame body) 51. Further, the cylindrical portions (guided portions) 140L1 and 140L2 are arranged on the other end side in the longitudinal direction of the cartridge 2, that is, on the other end side in the longitudinal direction of the drum frame (cartridge frame body) 51.

  Further, the protruding portion 103a of the interlocking member 103 of the cartridge 2 comes into contact with the main body guide portions 130L1, 130R1, the movable member right 120R, and the movable member left 120L. In this state, the interlocking member 103 rotates as the user inserts the cartridge 2 into the back of the apparatus main body 1. Along with this, the protective member 101 opens.

  The movable member right 120R, the movable member left 120L, and the main body guide portions 130R1, 130R2, 130L1, and 130L2 are arranged at one end side and the other end side in a direction orthogonal to the insertion direction in which the cartridge 2 is inserted into the apparatus main body 1. Is arranged.

  A description will be given of how the protection member 101 opens from the protection position to the retracted position as the cartridge 2 is inserted into the apparatus main body 1.

  1) The initial insertion 1 state will be described with reference to FIGS. 8a and 8b.

  When the user inserts the cartridge 2, the cylindrical portions (guided portions) 140R1 and 140L1 of the cartridge 2 land on the main body guide portions 130R1 and 130L1 fixed to the apparatus main body 1 (contact points P140R and P140L). The contact points P140R and P140L are on a surface inclined downward on the upstream side in the insertion direction of the guide portions 130R1 and 130L1.

  On the other hand, the protrusions 103a provided at both ends in the longitudinal direction of the interlocking member 103 come into contact with the movable member right 120R and the movable member left 120L that have moved outward from the opening 113 in conjunction with the opening / closing operation of the opening / closing cover 111. (Contact points P103R, P103L).

  The interlocking member 103 contacts the movable member right 120R and the movable member left 120L, thereby rotating relative to the cartridge 2 in the directions of the arrows in FIGS. 8a and 8b.

  Since the protection member 101 is rotatably supported by the interlocking member 103 and the arm 102, it rotates in the direction of the arrow in conjunction with the rotational movement of the interlocking member 103.

  2) The state of the initial insertion 2 will be described with reference to FIGS. 9a and 9b. The initial insertion 2 is a state in which the cartridge 2 is further inserted into the apparatus main body 1 from the initial insertion 1.

  The cylindrical portions (guided portions) 140R1 and 140L1 of the cartridge 2 are in contact with each other on a downwardly inclined surface on the downstream side in the insertion direction of the main body guide portions 130R1 and 130L1 (contact points P140R and P140L).

  The protrusion 103a of the interlocking member 103 is in contact with the movable member right 120R and the movable member left 120L, but the contact point is substantially the same position as the initial insertion 1 (contact points P103R, P103L).

  Therefore, the interlocking member 103 rotates in the direction of the arrow from the initial insertion 1, and accordingly, the protection member 101 is further retracted from the protection position.

  3) The state of the middle insertion period 1 will be described with reference to FIGS. 10a and 10b. The middle insertion period 1 is a state in which the cartridge 2 is further inserted into the apparatus main body 1 from the initial insertion stage 2.

  The cylindrical portions (guided portions) 140R1 and 140L1 are in contact with each other on a surface inclined downward on the downstream side in the insertion direction of the guide portions 130R1 and 130L1 (contact points P140R and P140L).

  The cylindrical portions (guided portions) 140R2 and 140L2 of the cartridge 2 are in contact with the main body guide portions 130R2 and 130L2, and guide the insertion direction of the cartridge 2.

  The right side of the protrusion 103a passes through the movable member right 120R and contacts the guide portion 130R1 (contact point P103R), while the left side of the protrusion 103a contacts the movable member left 120L (contact point P103L).

  The interlocking member 103 and the protection member 101 rotate further upstream in the insertion direction than the initial insertion 2.

  4) The state of the middle insertion period 2 will be described with reference to FIGS. 11a and 11b. The middle insertion period 2 is a state in which the cartridge 2 is further inserted into the apparatus main body 1 from the middle insertion period 1.

  The cylindrical portions 140R1 and 140L1 are in contact with the main body guide portions 130R1 and 130L1 on the downstream side in the insertion direction from the insertion middle period 1 (contact points P140R and P140L).

  The cylindrical portions 140R2 and 140L2 are in contact with the guide portions 130R2 and 130L2 to guide the insertion direction of the cartridge 2.

  The left side of the protruding portion 103a passes through the movable member left 120L and comes into contact with the guide portion 130L1 (contact point P103L), whereby the protruding portions 103a on the left and right sides come into contact with each other on the guide portions 130R1 and 130L1 (contact point). P103R, P103L).

  The interlocking member 103 and the protection member 101 rotate further upstream in the insertion direction than the middle stage 1 of insertion.

  The main body guide portion 130R1 has a portion that overlaps the movable member 120R in a direction orthogonal to the insertion direction. Further, the main body guide portion 130L1 has a portion that overlaps the movable member 120L in a direction orthogonal to the insertion direction (see FIGS. 7d, 8a, and 8b).

  Accordingly, when the protruding portion 103a passes through the movable member right 120R and is guided to the main body guide portion 130R1, the protruding portion 103a passes through the movable member left 120L and moves to the main body guide portion 130L1. When guided, the protrusion 103a can be smoothly moved from the movable members 120R and 120L to the main body guide portions 130R1 and 130L1.

  5) The state when the insertion is completed will be described with reference to FIGS. 12a and 12b.

  When the cartridge 2 is further pushed in from the middle insertion period 2, the cylindrical portions 140R1 and 140L1 fall into receiving recesses 130R3 and 130L3 provided at the terminal ends of the main body guide portions 130R1 and 130L1.

  Next, when the user closes the opening / closing cover 111, the mounting of the cartridge 2 to the apparatus main body 1 is completed.

  The movable member right 120 </ b> R and the movable member left 120 </ b> L are stored inside the apparatus main body 1 in conjunction with the operation of closing the opening / closing cover 111.

  Next, when the drive coupling 114 provided in the apparatus main body 1 rotates in the direction of the arrow in FIG. 6A, the coupling 114 and the drum coupling 13 fixed to the side end of the photosensitive drum 20 are engaged. Then, a driving force is transmitted from the apparatus main body 1, and the photosensitive drum 20 rotates in the same direction.

  At this time, a force is applied to the cartridge 2 to rotate it in the clockwise direction (in the direction of arrow R1 in FIG. 1), in the same way as the rotation direction of the photosensitive drum 20. The cylindrical portion 140R2 comes into contact with a slope 130R4 provided on the guide portion 130R2. Thereby, the position of the cartridge 2 with respect to the apparatus main body 1 is determined.

(Passing area of the protective member necessary for mounting the process cartridge to the main body)
A region necessary for the protection member 101 to pass when the cartridge 2 is mounted will be described with reference to FIGS. 13a and 13b.

  FIG. 13 a is a partial explanatory view for explaining a situation where the cartridge 2 is mounted on the apparatus main body 1 to which this embodiment is applied.

  FIG. 13B is a partial perspective view for explaining a state in which the cartridge 2 is mounted on the apparatus main body 1 to which this embodiment is applied.

  In FIG. 13 a and FIG. 13 b, the apparatus main body 1 depicts and describes the minimum necessary components so that the passage area of the protection member 101 can be seen.

  The position of the pickup roller 115 is shown assuming two cases. A solid line indicates the position when the opening / closing cover 111 described above is opened, and a two-dot chain line indicates a state where the opening / closing cover 111 is closed (in the conventional example, the pickup roller is in this position regardless of opening / closing of the opening / closing cover). Present).

  Further, the cartridge 2 will be described using only the protection member 101 and the interlocking member 103 so that the cartridge 2 at the time of completion of the insertion and the positions of the protection member 101 and the interlocking member 103 in the insertion process can be understood.

  In the apparatus main body 1 to which this embodiment is applied, as described above, the protrusion 103a of the interlocking member 103 contacts the movable member right 120R (movable member left 120L) at the initial insertion.

  In the middle of insertion, the protruding portion 103a is transferred from the movable member right 120R (movable member left 120L) to the main body guide portion 130R1 (main body guide portion 130L1), and further pushes the cartridge 2 forward (back side). Thereby, the insertion of the cartridge 2 into the apparatus main body 1 is completed. In other words, the guide portion 130R1 (the guide portion 130L1) can be provided with a guide function for guiding the cartridge 2 in the mounting direction and a function for moving the protection member 101 from the protection position to the retracted position. Therefore, according to the present embodiment, a reduction in cost and a reduction in size of the apparatus can be realized.

  In the above-described process, the protective member 101 follows the trace of the pickup roller 115 and the conveyance guide 151. That is, the interlocking member 103 is held by the movable member 120 at the initial stage of mounting the cartridge 2 to the apparatus main body 1. And after passing the movable member 120, it is hold | maintained at main body guide part 130R1 (main body guide part 130L1). Therefore, the interlocking member 103 does not descend below the movable member 120 and the main body guide portion 130R1 (main body guide portion 130L1), and thus the height of the apparatus main body 1 can be further reduced.

  As described above, when this embodiment is applied, the protection member 101 gradually rotates from the protection position to the retracted position from the beginning of inserting the cartridge 2 into the apparatus main body 1. That is, the protective member 101 starts an opening operation from the outside (opening 113) of the apparatus main body. When the protection member 101 moves from the protection position to the retracted position, the protection member 101 passes through a long and narrow space region that extends from the outside to the inside of the apparatus main body 1. As a result, the space area in the apparatus main body 1 occupied by the protective member 101 for performing the opening / closing operation can be reduced, so that the apparatus main body can be downsized.

As shown in FIG. 14, when the reading device 117 or the like is installed on the upper side, if a space for inserting the cartridge 2 from above is secured, the position of the reading device increases accordingly.

  And there is a desirable height considering the accessibility to the reader. For this reason, it is preferable to insert the cartridge 2 at a more gentle angle as in the present embodiment, rather than inserting the cartridge from above, and the size of the apparatus is not increased.

  By applying the present embodiment as described above, a compact image forming apparatus can be provided to the user without causing an increase in the size of the apparatus main body (expansion of installation area and increase in height).

  Further, by applying the present embodiment, the guide portion 130R1 (guide portion 130L1) has a guide function when the cartridge 2 is attached to and detached from the apparatus main body 1 and a function for opening and closing the protection member 101. The apparatus can be made compact. In addition, it is possible to reduce the use parts and cost.

  In the present embodiment, in the process of inserting the cartridge 2, the protrusions 103a on both sides of the interlocking member 103 come into contact with the movable member right 120R and the movable member left 120L, and the guide portion 130R1 and the guide portion 130L1, respectively. explained.

  Actually, only one side may come into contact with each other in consideration of manufacturing shape error, assembly error, and mounting operation. Further, if the interlocking member 103 is a material having rigidity such as metal, the contact may be only on one side.

  In the present embodiment, the protrusions 103a of the interlocking member 103, the movable member right 120R, the movable member left 120L, and the contact points P103R and P103L of the guide members 130R1 and 130L1 are moved from the movable members 120R and 120L to the guide members 130R1 and 130L1. And explained in the order of delivery.

  An example of insertion outside this order will be described with reference to FIGS. 15a, 15b, 16a, and 16b.

  15a and 15b are explanatory views of the state of the initial insertion 2 (deformation) of the cartridge 2. FIG.

  FIGS. 16A and 16B are explanatory views of the state of the insertion period 1 (deformation) of the cartridge 2.

  In the initial insertion stage 2, the degree of freedom in the mounting direction of the cartridge 2 (more specifically, the attitude angle of the cartridge 2) is given. Therefore, in the initial insertion 2 (FIGS. 9a and 9b), the cartridge 2 can be turned in the arrow S direction. In that case, the contact points 103R and P130L1 exist on the guide members 130R1 and 130L1. This state is referred to as initial insertion 2 (modified example) and is shown in FIG.

  Further, a state in which the cartridge 2 is further inserted into the apparatus main body 1 from the initial insertion stage 2 (modified example) is referred to as an intermediate insertion period 1 (modified example), and this state is shown in FIG.

  In the middle insertion period 1 (modified example), the rotation restricting portion 56 of the cartridge 2 comes into contact with the guide entrance portion 130R7. As a result, the cartridge 2 is rotated in the direction of the arrow T in the drawing around the axis of the cylindrical portions 140L1 and 140R1.

  In this state, the protrusion 103a of the interlocking member 103 is in contact with the movable member right 120R and the movable member left 120L.

  As described above, when the cartridge 2 is inserted in a posture close to the vertical direction in the initial stage of insertion, the contact points P103R and P103L exist in the guide portions 130R1 and 130L1 fixed to the apparatus main body 1. When the cartridge 2 continues to be inserted into the apparatus main body 1, the contact points P103R and P103L are received on the movable member right 120R and the movable member 120L. When the insertion is further continued, the contact points P103R and P103L move onto the guide portions 130R1 and 130L1 fixed to the apparatus main body 1.

  Even in the case of this modification, the contact points P103R and P103L are transferred smoothly, and the clearance between the protection member 101, the conveyance guide 151, and the pickup roller 115 is maintained.

  Even when this modification is applied, a compact image forming apparatus can be provided to the user without causing an increase in the size of the apparatus main body (enlargement of the installation area and increase in height) as in the above-described embodiments.

  Similarly to the above-described embodiment, by applying this modification, a guide function when the cartridge 2 is attached to and detached from the apparatus main body 1 with respect to the guide portion 130R1 (guide portion 130L1), and a protective member Since the function of opening and closing 101 can be provided, the apparatus can be made compact. In addition, it is possible to reduce the use parts and cost.

1 is a longitudinal sectional view of an image forming apparatus. It is a longitudinal cross-sectional view of a process cartridge. It is a longitudinal cross-sectional view of a developing device. It is an external appearance perspective view explaining the state which has the protection member 101 in a protection position. It is an external appearance perspective view explaining the state which has the protection member 101 in a retracted position. FIG. 3 is an external perspective view of the process cartridge as viewed from the upper surface side. It is state explanatory drawing which attaches and detaches a process cartridge. It is state explanatory drawing which attaches and detaches a process cartridge. It is state explanatory drawing which attaches and detaches a process cartridge. It is explanatory drawing of the guide structure of the right side which guides attachment or detachment of a process cartridge. It is explanatory drawing of the left guide structure which guides attachment or detachment of a process cartridge. It is a partial view explaining the state of the apparatus main body when the open / close cover is closed. It is a partial view explaining the state of the apparatus main body when the open / close cover is closed. It is a figure explaining the cover 119. FIG. FIG. 10 is a configuration explanatory diagram illustrating the operation of a cover 119. FIG. 11 is an explanatory diagram of a process cartridge insertion state for explaining the role of a cover 119. It is a process cartridge insertion state part explanatory drawing for demonstrating the role of the cover 119. FIG. FIG. 3 is an explanatory diagram of the state of the process cartridge 2 at the initial insertion stage 1. FIG. 3 is an explanatory diagram of the state of the process cartridge 2 at the initial insertion stage 1. FIG. 6 is an explanatory diagram of a state of an initial insertion 2 of the process cartridge 2. FIG. 6 is an explanatory diagram of a state of an initial insertion 2 of the process cartridge 2. FIG. 5 is an explanatory diagram of a state of a process cartridge 2 in a middle period 1 of insertion. FIG. 5 is an explanatory diagram of a state of a process cartridge 2 in a middle period 1 of insertion. FIG. 7 is a state explanatory diagram of a process cartridge 2 in a middle insertion period 2; FIG. 7 is a state explanatory diagram of a process cartridge 2 in a middle insertion period 2; FIG. 6 is an explanatory diagram of a state when insertion of a process cartridge 2 is completed. FIG. 6 is an explanatory diagram of a state when insertion of a process cartridge 2 is completed. It is a partial explanatory view explaining the situation where the process cartridge is mounted on the apparatus main body to which the present embodiment is applied. It is a partial explanatory view explaining the situation where the process cartridge is mounted on the apparatus main body to which the present embodiment is applied. It is a schematic perspective view explaining the application example of a present Example. FIG. 6 is an explanatory diagram of a state of an initial insertion 2 (deformation) of the process cartridge 2. FIG. 6 is an explanatory diagram of a state of an initial insertion 2 (deformation) of the process cartridge 2. FIG. 6 is an explanatory diagram of a state of a process cartridge 2 in a middle insertion period 1 (deformation). FIG. 6 is an explanatory diagram of a state of a process cartridge 2 in a middle insertion period 1 (deformation).

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Image forming apparatus main body (apparatus main body), 2 ... Process cartridge, 20 ... Photosensitive drum, 40c ... Developing frame, 51 ... Drum frame, 101 ... Protection member, 102 ... Arm, 103 ... Interlocking member, 111 ... Opening and closing cover, 113 ... opening, 120R ... movable member right, 120L ... movable member left, 130L1, 130L2 ... guide portion, 130R ... guide right, 130R1 / 130R2 ... guide portion, P ... recording medium (sheet material)

Claims (2)

An electrophotographic photosensitive drum;
Process means acting on the electrophotographic photosensitive drum;
A cartridge frame for supporting the electrophotographic photosensitive drum and the process means;
A protective member that covers and protects the exposed portion of the electrophotographic photosensitive drum exposed from the cartridge frame, and a protection position that covers the exposed portion and retreats from the protection position to expose the exposed portion. A protective member movable between the exposed positions;
An interlocking member that interlocks with the protective member;
In an electrophotographic image forming apparatus that can attach and detach a process cartridge having an image on a recording medium,
An opening through which the process cartridge passes when the process cartridge is inserted into the apparatus main body of the electrophotographic image forming apparatus, and through which the process cartridge passes when the process cartridge is taken out of the apparatus main body;
An open / close cover that is movable with respect to the apparatus main body and can take a closed position for closing the opening and an open position for opening the opening;
In conjunction with the opening / closing cover moving from the closed position to the open position, at least a portion is positioned outward from the opening, and the opening / closing cover is interlocked to move from the open position to the closed position. A movable member positioned in the apparatus main body, wherein the protective member is moved from the closed position toward the upstream side in the insertion direction in conjunction with an insertion operation of inserting the process cartridge into the apparatus main body from the closed position to the open position. A movable member that contacts a part of the interlocking member when the process cartridge is inserted into the apparatus main body,
A main body guide that is fixedly provided in the apparatus main body and guides the process cartridge in a mounting direction by contacting a guided portion of the process cartridge when the process cartridge is inserted into the apparatus main body. The movable member is inserted when the process cartridge is inserted into the apparatus main body in order to further move the protective member from the closed position to the open position toward the upstream side in the insertion direction in conjunction with the insertion operation. A body guide that contacts a part of the interlocking member that has passed through
I have a,
In the process of inserting the process cartridge into the apparatus main body, the main body guide is arranged in a direction perpendicular to the insertion direction so that a part of the interlocking member moves smoothly from passing through the movable member to the main body guide. Has an overlapping portion with the movable member .   2. The electrophotographic image forming apparatus according to claim 1, wherein the movable member and the main body guide are disposed on one end side and the other end side in a direction orthogonal to the insertion direction.