JP2006139068A - Image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image forming apparatus for protecting the surface of a belt body in opening operation of a door in the image forming apparatus of configuration exposing the surface of the belt body in the opening operation of the door by including the belt body. <P>SOLUTION: The image forming apparatus includes a conveying path 25, an exposure means 6, processing cartridges a-d, a fixing means 5, an intermediate transfer belt 41, a frame body 30 supporting the lower part of the apparatus, and the door 10 rotated by hinges 101 and 102 arranged on the frame body 30. The door 10 is at a position retreated from the belt body 41 in a state where the door 10 is closed, and the image forming apparatus includes a protection member 103 moved to a position for protecting the belt body 41 in a state where the door 10 is opened. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an image forming apparatus having a belt body such as a transfer belt or an intermediate transfer belt.

  2. Description of the Related Art Conventionally, image forming apparatuses such as copying machines, printers, and fax machines are configured so that each unit can be attached and detached for easy maintenance. These units are usually accessible by opening the door of the image forming apparatus.

  Here, if the photosensitive drum or the transfer roller is exposed when the open / close door is in the open position, the user may be injured unexpectedly during JAM (paper jam) processing. In order to prevent such an accident, there is a transfer roller provided with a protective shutter (see, for example, Patent Document 1).

  Here, the configuration shown in Patent Document 1 is an image forming apparatus that does not use an intermediate transfer belt, but a relatively large unit such as an intermediate transfer belt usually has no protective shutter because it is replaced by a service person. It is. In addition, since the conventional image forming apparatus has a pull-out configuration using a lever or the like when the belt body is replaced, the belt body is not exposed only by opening the door.

  In recent years, an image forming apparatus has been proposed in order to improve operability including maintenance such as JAM processing and belt body replacement, and to reduce costs (for example, see Patent Document 2).

  The image forming apparatus disclosed in Patent Document 2 has an image forming unit under the intermediate transfer belt in a short vertical path. Such a configuration has an advantage that FPOT (first print out time) is fast. Further, the belt body is exposed with the open / close door open, and the belt body can be taken out. For this reason, the exchangeability of the belt body is improved, and there is an advantage that more space is saved by eliminating the space such as the drawer rail.

JP-A-11-288209 JP-A-2004-29211 (FIG. 4)

  However, as in Patent Document 2, when the belt body such as the intermediate transfer belt can be taken out only by opening the opening / closing door, the belt body is exposed when the door is opened. Here, when the user opens and closes the door, there is a risk of accidentally touching the belt body and damaging the belt body.

  SUMMARY OF THE INVENTION An object of the present invention is to provide an image forming apparatus having a belt body and protecting the belt body surface by opening the door in an image forming apparatus having a configuration in which the belt body surface is exposed by opening the door. .

  In order to achieve the above object, a typical configuration according to the present invention includes a conveyance path, an exposure unit, an image forming unit, a fixing unit, a belt body, a frame body that supports the lower part of the apparatus, and the frame body. In the image forming apparatus having a door rotated by a hinge disposed on the door, the door is in a position retracted from the belt body when the door is closed, and the door is open. Then, it has the protection member which moves to the position which protects the said belt body, It is characterized by the above-mentioned.

  According to the above configuration, in the image forming apparatus having the belt body and the belt body surface exposed by the door opening operation, the belt body surface can be protected by the door opening operation.

[First Embodiment]
A first embodiment of the present invention will be described with reference to the drawings. In the description, first, an outline of the image forming apparatus will be described, and then a characteristic embodiment will be described.

(Image forming apparatus and image forming process)
As shown in FIG. 1, the image forming apparatus includes, for example, process cartridges a, b, c, and four image forming units arranged in parallel to form toner images of yellow, magenta, cyan, and black. d. In addition, each image forming unit includes a photosensitive drum 1 (1a, 1b, 1c, 1d) as an image carrier, and an intermediate transfer that is arranged above the photosensitive drum 1 in such a manner that the photosensitive drum 1 is vertically cut. A belt (belt body) 40 is provided.

  Process means such as a charging means, a developing means, and a cleaning means (not shown) are disposed around the photosensitive drum 1. The process means is integrally unitized with the photosensitive drum 1 as process cartridges a, b, c, and d.

  An image forming process will be described. First, the photosensitive drum 1 is uniformly charged by charging means provided in each process cartridge. Next, on the photosensitive drum 1, scanning light of each color of yellow, magenta, cyan, and black subjected to color separation is exposed by the exposure unit 6. As a result, electrostatic latent images of yellow, magenta, cyan, and black are formed on the photosensitive drum 1, respectively. Each electrostatic latent image is developed by developing means. As a result, yellow, magenta, cyan, and black toner images are formed on the photosensitive drum 1.

  The developed toner image reaches a primary transfer portion where the photosensitive drum 1 and the intermediate transfer belt 41 come into contact with the rotation of the photosensitive drum 1. Then, a primary transfer bias is applied from the electrical substrate to the primary transfer rollers 2 (2a, 2b, 2c, 2d) disposed to face the photosensitive drums 1 (1a, 1b, 1c, 1d). The By this bias, the toner images on the photosensitive drum 1 are sequentially transferred to the intermediate transfer belt 41.

  On the other hand, the transfer material P transported to the primary transfer portion is stored in the feeding cassette 4. The feeding cassette 4 can be pulled out in the right direction A of the arrow in the figure. By pulling out, for example, replenishment of the transfer material P, jam processing at the time of jam in the feeding cassette 4 and the like can be performed.

  The transfer material P is fed one by one from the feeding cassette 4 by the pickup roller 8. The transfer material P passes through the conveyance path 25 and is registered with the registration roller 9 to be synchronized with the rotation of the photosensitive drum 1, and then the transfer material P is transferred to the nip portion constituted by the secondary transfer roller 3 and the intermediate transfer belt 41. Be transported. In the process of being conveyed, the toner image on each photosensitive drum 1 (1a, 1b, 1c, 1d) is transferred onto the transfer material P in a superimposed manner from the intermediate transfer belt 41 to the transfer material P.

  The transfer material P onto which the toner image has been transferred is conveyed to the fixing unit 5. In the fixing unit 5, the toner image is melted and mixed with the transfer material P by receiving heat and pressure, and is fixed and fixed to the transfer material P. After a full-color print image is formed on the transfer material P, the transfer material P is discharged to the discharge tray 7 by the discharge means 21 provided downstream of the fixing means 5.

(Characteristic configuration)
A characteristic configuration according to the image forming apparatus of the present invention will be described. First, the movement of the protective shutter (protective member) 103 of the intermediate transfer belt 41 according to the configuration of the housing of the image forming apparatus and the opening and closing of the doors 10 and 20 of the image forming apparatus will be described with reference to FIGS. . Next, the detailed operation of the protective shutter 103 will be described with reference to FIGS.

  FIG. 1 is a cross-sectional view illustrating the entire image forming apparatus, FIG. 2 is an explanatory view when the front door of the image forming apparatus is opened, and FIG. 3 is a view of opening the front door and the upper door of the image forming apparatus. It is explanatory drawing at the time.

(Configuration of the housing of the image forming apparatus)
As shown in FIG. 1, the housing of the image forming apparatus includes a frame 30 in which a process cartridge, an exposure means 6, a feeding cassette 4 and the like are assembled at the lower part of the apparatus, and a conveyance path 25 and a fixing at the front part of the apparatus. The front door 20 on which the means 5 is disposed, and the upper door 10 to which the belt body and the primary transfer roller 2 are assembled at the upper rear part of the apparatus.

  A hinge 101 is provided at the rear end of the frame 30 so that the upper door 10 can be opened and closed by rotating to the rear of the apparatus with respect to the frame 30. In addition, a hinge 102 is provided at the front end of the frame 30 so that the front door 20 can be opened and closed by rotating forward with respect to the frame 30 with respect to the apparatus. By these hinges 101 and 102, the upper door 10 and the frame 30 and the front door 20 and the frame 30 are assembled so as to be rotatable. The upper door 10 is provided with a protective shutter (protective member) 103 that moves between a retracted position and a protective position in accordance with opening and closing. The positional relationship of the shutter 103 in each state of the doors 10 and 20 of the image forming apparatus will be described.

  The state shown in FIG. 1 is a normal state during image formation or standby. At this time, the upper door 10 and the front door 20 are both closed. In this case, the protective shutter 103 is in a position (retracted position) retracted from the end roller 41a so as not to cover the side of the end roller 41a.

  In a state where the protective shutter 103 is in the retracted position, the end roller 41 a of the intermediate transfer belt 41 contacts the secondary transfer roller 3. Therefore, the function of the intermediate transfer belt 41 is not hindered, and the toner on the intermediate transfer belt 41 is transferred to the transfer material P in the image forming process.

  The state shown in FIG. 2 is a state of JAM (paper jam) processing. At this time, only the front door 20 is open, and the upper door 10 is closed. In this case, the protective shutter 103 remains in the retracted position because the upper door 10 is closed. That is, it does not move in the direction of the arrow C and remains held in the direction of the arrow B.

  Here, a JAM processing label 111 is affixed to the surface 103 f of the protective shutter 103. The label 111 describes the JAM processing method, and the user can remove the transfer material P stagnating in the transport path 25 of the apparatus according to the instruction of the label 111.

  The state shown in FIG. 3 is a state at the time of maintenance. During maintenance, the user can replace the process cartridges a to d and the intermediate transfer belt 41. At this time, both the upper door 10 and the front door 20 are open. In this case, simultaneously with the upward rotation of the upper door 10, the protective shutter 103 rotates in the direction of arrow C and moves to the side of the end roller 41a to protect the intermediate transfer belt 41 (protective position). become.

  In a state where the protective shutter 103 is in the protective position, the back surface 103b of the protective shutter 103 is visible to the user. Here, an instruction label 112 is affixed to the back surface 103b. The label 112 describes a replacement method and handling method of the intermediate transfer belt 41 or a replacement method and handling method of the process cartridges a to d. Therefore, the user can perform the replacement work according to the instruction of the label 112.

  A protective shutter 103 protects the vicinity of the end roller 41a of the intermediate transfer belt 41. For this reason, it is possible to prevent the intermediate transfer belt 41 from being contaminated or scratched when the user's hand hits the upper door 10.

(Operation of the shutter 103 when the doors 10 and 20 of the image forming apparatus are opened and closed)
Next, the operation of the protective shutter 103 will be described in detail. 10 is a perspective view of the opening / closing mechanism 10a of the protective shutter 103, FIG. 11 is a state diagram of the opening / closing mechanism 10a when the upper door 10 is closed, and FIG. 12 is an opening / closing operation when the upper door 10 is open. It is a state diagram of the mechanism 10a.

  The configuration of the opening / closing mechanism 10a will be described with reference to FIG. As shown in FIG. 10 (a), an opening / closing mechanism 10 a for the protective shutter 103 is disposed at the lower part of the upper door 10. As shown in FIG. 10B, the opening / closing mechanism 10a includes a protective shutter 103 that rotates about a rotation center 103a, a rack 104 that has a pinion 104g that meshes with a gear 103g attached to the rotation center 103a, A cam 105 for rotating around the rotation center 105a to move the rack 104 back and forth, and a cam contact surface 107 fixed to the frame side of the upper door 10 are provided.

  A state in which the protective shutter 103 is in an open state when the upper door 10 is in a closed state will be described with reference to FIG. As shown in FIG. 11A, when the upper door 10 is in a closed state, the protective shutter 103 is in an open state so that the intermediate transfer belt 41 is brought into contact with the secondary transfer roller 3.

  As shown in FIG. 11B, when the cam contact surface 107 is in contact with the cam 105, the cam 105 is urged in the direction B in the drawing. At this time, since the rack 104 is also urged in the B direction where the rotation center 103a is located, the rotation center 103a of the protective shutter 103 rotates counterclockwise in the drawing and is positioned at the retracted position of the protective shutter 103.

  A state in which the protective shutter 103 is in the closed state when the upper door 10 is in the open state will be described with reference to FIG. As shown in FIG. 12A, when the upper door 10 is in the open state, the cam 105 is released from the cam contact surface 107.

  Then, as shown in FIG. 12B, the cam 105 is rotated in the C direction by the spring 106, and the rack 104 slides in the C direction. At this time, the slide of the rack 104 causes the protection shutter 103 to rotate in the C direction from the retracted position via the gear 103g of the rotation center 103a, and stops at the protection position that protects the intermediate transfer belt 41.

  As described above, the protective shutter 103 rotates in conjunction with the opening and closing of the upper door 10. When the upper door 10 is closed, the protective shutter 103 is in the retracted position, and when the upper door 10 is in the open state, the protective shutter 103 is in the protected position.

  Here, a buffer member 108 is disposed on the surface 103 f of the protective shutter 103. For this reason, even if the user accidentally grabs the intermediate transfer belt 41 over the protective shutter 103 and the protective shutter 103 is urged toward the intermediate transfer belt 41 when the upper door 10 is in the open state, the surface of the belt is damaged. It is the structure which prevents sticking.

  Further, when replacing the intermediate transfer belt 41, the cam 105 is manually rotated toward the retracted position. Then, the protective shutter 103 is opened by fixing the cam 105 to a hook portion (not shown). As a result, the end roller 41a side of the intermediate transfer belt 41 is exposed, so that the intermediate transfer belt 41 can be easily removed. In this way, the replacement work can be facilitated.

  The area where the protective shutter 103 protects the intermediate transfer belt 41 is preferably the entire area where the intermediate transfer belt 41 is exposed. However, the area to be protected is determined according to the overall size of the apparatus, the retracted area of the protective shutter 103, the component cost, and the risk of exposure of the intermediate transfer belt 41.

[Second Embodiment]
A second embodiment of the present invention will be described with reference to the drawings. A characteristic configuration of the present embodiment will be described with reference to FIGS. The same configurations as those in the above-described embodiment are denoted by the same reference numerals and description thereof is omitted.

  FIG. 4 is a cross-sectional view illustrating the entire image forming apparatus according to the second embodiment, FIG. 5 is an explanatory view when the front door of the image forming apparatus according to the second embodiment is opened, and FIG. It is explanatory drawing when the front door and upper door of the image forming apparatus of an embodiment are opened.

  As shown in FIG. 4, the image forming apparatus includes an upper door 10 that rotates upward about a hinge 101 located in the vicinity of the upper portion of the frame body 30, and a photosensitive belt 42 that is disposed substantially horizontally on the upper door 10. When the transport path 25 configured in an oblique direction, the exposure unit 6 disposed below the photosensitive belt 42, and the position when the transport path 25 is viewed from the front face the front, the lower part of the image forming apparatus is rotated. It has a front door 20 that can be opened and closed on the front side as a moving center and includes a conveyance path 25, and a fixing means 5 arranged on the frame 30 side. The protective shutter 103 of the photosensitive belt 42 is in the vicinity of the end of the upper door 10. Placed in.

  The state shown in FIG. 4 is a normal state during image formation or standby. At this time, the upper door 10 and the front door 20 are both closed. In this case, the protective shutter 103 is in a position (retracted position) retracted from the end roller 42a so as not to cover the side of the end roller 42a.

  In the state where the protective shutter 103 is in the retracted position, the end roller 42 a of the intermediate transfer belt 42 contacts the secondary transfer roller 3. Therefore, the function of the intermediate transfer belt 41 is not hindered, and the toner on the intermediate transfer belt 41 is transferred to the transfer material P in the image forming process.

  The state shown in FIG. 5 is a state of JAM (paper jam) processing. At this time, only the front door 20 is open, and the upper door 10 is closed. In this case, the protective shutter 103 remains in the retracted position because the upper door 10 is closed.

  Here, a JAM processing label 111 is attached to the upper portion of the upper door 10 in the vicinity of the retracted position of the protective shutter 103. The label 111 describes the JAM processing method, and the user can remove the transfer material P stagnating in the transport path 25 of the apparatus according to the instruction of the label 111.

  The state shown in FIG. 6 is a state at the time of maintenance. During maintenance, the user can replace the process cartridges a to d and the intermediate transfer belt 42. At this time, both the upper door 10 and the front door 20 are open. In this case, simultaneously with the upward rotation of the upper door 10, the protective shutter 103 slides in the direction of arrow C and moves to the side of the end roller 42a to a position where the intermediate transfer belt 42 is protected (protective position). Become.

  In a state where the protective shutter 103 is in the protective position, the surface 103f of the protective shutter 103 is visible to the user. Here, an instruction label 112 is affixed to the surface 103f. The label 112 describes a replacement method and a handling method of the photosensitive belt 42 or a replacement method and a handling method of the process cartridges a to d. Therefore, the user can perform the replacement work according to the instruction of the label 112.

  A protective shutter 103 protects the vicinity of the end roller 42a of the photosensitive belt 42. For this reason, when the user's hand hits the upper door 10, it is possible to prevent the photosensitive belt 42 from being contaminated or scratched.

  In this embodiment, the photosensitive belt 42 is used as the belt body, but the intermediate transfer belt 41 as in the first embodiment may be used. Further, the conveyance path 25 may be substantially vertical rather than oblique. Further, the protective shutter 103 is not a slide type, but may be a rotary type and a label corresponding to the state may be attached to the front and back of the protective shutter 103 itself to assist JAM processing and belt body handling. These differ depending on the size, cost, and quality of the image forming apparatus.

  In the present embodiment, the protective shutter 103 is slid and moved. Unlike the first embodiment, the protective shutter 103 is mechanically moved by moving the rack 104 as the cam 105 rotates. Since there is no change in sliding, the description is omitted. However, if the sliding configuration is adopted, the protective shutter 103 can be moved in part using another method such as electromagnetic or electrical. The same applies to later-described embodiments.

[Third Embodiment]
A third embodiment of the present invention will be described with reference to the drawings. A characteristic configuration of the present embodiment will be described with reference to FIGS. 7 and 8. The same configurations as those in the above-described embodiment are denoted by the same reference numerals and description thereof is omitted.

  FIG. 7 is a cross-sectional view illustrating the entire image forming apparatus according to the third embodiment, and FIG. 8 is an explanatory view when the front door of the image forming apparatus according to the third embodiment is opened.

  As shown in FIG. 7, the image forming apparatus includes an upper door 10 that pivots upward about a hinge 101 located near the upper portion of the frame body 30, and a conveyance path 25 that is configured in a substantially vertical direction on the upper door 10. A front door 20 that pivots forward around a hinge 102 located near the front lower portion of the frame 30, an intermediate transfer belt 43 that is disposed in a substantially vertical direction on the front door 20, and a side of the intermediate transfer belt 43 And the fixing means 5 disposed on the front door 20 side, and the protective shutter 103 of the intermediate transfer belt 43 is located on the upper rear side of the front door 20. It is arranged so as to be rotatable.

  The protective shutter 103 is configured to rotate from the retracted position retracted from the upper end of the intermediate transfer belt 43 to the protected position for protection when the front door 20 is open. When the front door 20 starts to be opened, the processing label 111 stretched on the surface 103f of the protective shutter 103 becomes visible. The label 111 describes the JAM processing method, and the user can remove the transfer material P stagnating in the transport path 25 of the apparatus according to the instruction of the label 111.

  Also, as shown in FIG. 8, when the front door 20 is opened and opened more than a predetermined amount, the protective shutter 103 rotates and moves to the protected position. Then, the instruction label 112 becomes visible. The instruction label 112 describes a replacement method and handling method for the intermediate transfer belt 43 or a replacement method and handling method for the process cartridges a to d. Therefore, the user can perform the replacement work according to the instruction of the label 112.

[Fourth Embodiment]
A fourth embodiment of the present invention will be described with reference to the drawings. A characteristic configuration of the present embodiment will be described with reference to FIG. The same configurations as those in the above-described embodiment are denoted by the same reference numerals and description thereof is omitted. FIG. 9 is a cross-sectional view illustrating the entire image forming apparatus of the fourth embodiment.

  In the present embodiment, the image forming apparatus includes the opening / closing door 10 including the transfer material conveyance belt 44, and the protection shutter 103 of the transfer material conveyance belt 44 protects the transfer material conveyance belt 44 when the opening / closing door 10 is open. It is configured to rotate to a position.

1 is a cross-sectional view illustrating an entire image forming apparatus according to a first embodiment. Explanatory drawing when the front door of the image forming apparatus of 1st Embodiment is opened. FIG. 3 is an explanatory diagram when the front door and the upper door of the image forming apparatus according to the first embodiment are opened. Sectional drawing explaining the whole image forming apparatus of 2nd Embodiment. Explanatory drawing when the front door of the image forming apparatus of 2nd Embodiment is opened. Explanatory drawing when the front door and upper door of the image forming apparatus of 2nd Embodiment are opened. Sectional drawing explaining the whole image forming apparatus of 3rd Embodiment. Explanatory drawing when the front door of the image forming apparatus of 3rd Embodiment is opened. Sectional drawing explaining the whole image forming apparatus of 4th Embodiment. The perspective view of the opening / closing mechanism of a protective shutter. The state diagram of the opening and closing mechanism when the upper door is in the closed state. The state figure of an opening-and-closing mechanism when an upper door is an open state.

Explanation of symbols

P: Transfer material,
a Process cartridge (image forming unit),
b: Process cartridge (image forming unit),
c: Process cartridge (image forming unit),
d: Process cartridge (image forming unit),
5: Fixing means,
6 ... exposure means,
10… upper door,
10a ... opening and closing mechanism,
20… Front door,
25… Conveying path,
30 ... the frame,
41 ... Intermediate transfer belt (belt body)
42 ... photoreceptor belt (belt body),
43 ... Intermediate transfer belt (belt body)
44 ... transfer material conveying belt (belt body),
101… Hinge,
102 ... hinge,
103 ... Protective shutter (protective member),
108 ... buffer member,
111… Process label (label),
112… Instruction label (label)

Claims (9)

Image formation having a conveyance path for conveying a transfer material, an exposure unit, an image forming unit, a fixing unit, a belt, a frame that supports the lower part of the apparatus, and a door that opens and closes to the frame. In the device
The door has a protective member that is in a position retracted from the belt body when the door is closed, and moves to a position that protects the belt body when the door is open. Image forming apparatus. The image forming apparatus according to claim 1, wherein the belt body is disposed on the door. The image forming apparatus according to claim 1, wherein the exposure unit is disposed below the image forming unit, and the image forming unit is disposed below the belt body. There are a plurality of the doors, and when the conveyance path is viewed from the front, the front door including the fixing unit and the conveyance unit among the plurality of doors forms an image with the lower part of the image forming apparatus as a rotation center. The image forming apparatus according to claim 3, wherein the image forming apparatus is configured to be openable and closable on a front side of the apparatus. There are a plurality of doors, the fixing unit is fixed to the frame body side, and the front door including the transport unit is centered on the lower part of the image forming apparatus when the transport path is viewed from the front. The image forming apparatus according to claim 3, wherein the image forming apparatus is configured to be openable and closable on a front side of the image forming apparatus. The image forming apparatus according to claim 1, wherein a region protected by the protection member is in the vicinity of an outer end portion from which the belt body projects. The image forming apparatus according to claim 6, wherein a label indicating a different display between the opened state and the closed state is attached to the protection member. The image forming apparatus according to claim 6, wherein a buffer member is disposed on a surface of the protection member on the belt body side at a position where the protection member protects the belt body. . The image forming apparatus according to claim 1, wherein the belt body is any one of a photosensitive belt, an intermediate transfer belt, and a transfer material conveyance belt that conveys a transfer material.

Images