JP2005301075A - Developing unit - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a developing unit having a mechanism which is a simple structure, can easily be assembled, and with which electrical connection between the terminals of a device main body and an electronic component can be ensured. <P>SOLUTION: The fourth contact member 94 and the fifth contact member 95 made of metal wire materials are disposed on the sides of the developing unit. One end of each of the contact members are inserted and held in a lock bar 106, 107 formed in the shape of a coil and projected against the internal side of a storage recess section 97. The other end of each of the contact members are bent in the shape of a key and inserted and locked in an insertion hole 101, 105. A fuse tube 96 is held between the ends of the coils of the both contact members so as to be in pressure contact with them, and is thus electrically connected to them. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a developing device that is detachably mounted on an image forming apparatus such as a copying machine, a printer, or a facsimile machine.

Various types of image forming apparatuses have been developed from a technical point of view, such as high-resolution image formation, or from an application point of view, such as business use or home use. As for the developing devices that can be attached to and detached from many types of image forming apparatuses, naturally, various types of developing devices have been developed. Accordingly, it is necessary to attach a developing device corresponding to a predetermined model of the image forming apparatus, and attaching an incompatible developing device may cause a failure of the image forming apparatus. Therefore, it is necessary to ensure compatibility between the image forming apparatus and the developing device mounted. For example, in Patent Document 1, when a fuse and a resistor are attached to a developing cartridge and the fuse is mounted on the image forming apparatus main body, the initial is detected by the fuse conduction, the fuse is blown, and the resistance value is further checked. It is described that it is determined whether the cartridge matches the apparatus main body. Patent Document 2 describes a fuse holder in which a fuse tube is pressed and held by a coil spring.
JP-A-5-249777 Japanese Utility Model Publication No. 7-27046

  In the above-mentioned prior literature, a fuse is attached to the developing device and is attached to the apparatus main body so that the fuse is blown. However, when an electronic component such as a fuse is attached to the developing device, the terminal on the apparatus main body side is electrically connected to the terminal. It is essential to ensure a secure connection. However, since the developing device is detachable and is removed and discarded or disassembled due to the consumption of the developer, it is necessary to reduce the cost as much as possible, and the mechanism for electrically connecting electronic components is also reliable. You must be able to connect and reduce costs.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a developing device including a mechanism that can be easily assembled with a simple structure and that can reliably connect an electrical terminal to a terminal on the apparatus body side. To do.

  The developing device according to the present invention includes a conductive member made of a metal wire material that comes into contact with a terminal disposed on the apparatus main body side at the time of mounting in the developing device that is inserted and mounted inside the image forming apparatus. The conducting member is characterized in that one end portion is formed at a contact portion with respect to the terminal and the other end portion is formed at a pressure contact portion that is electrically connected to the electronic component. Furthermore, the contact portion of the conducting member is formed by bending. Furthermore, the pressure contact portion of the conducting member is formed in a coil shape. Furthermore, the electronic component is held by the pressure contact portions of the conducting member being pressed from both sides to the terminals at both ends of the electronic component. Further, the electronic component is a fuse used for identifying whether the developing device is new or used.

  By having the above-described configuration, the conductive member that contacts the terminal disposed on the apparatus main body side is configured with a conductive member made of a metal wire, so for example whether the developer is new or used The mechanism for electrical connection between the electronic component such as a fuse for identifying the device and the apparatus main body side consists of only the wire material, and the structure can be very simple. Since the assembling work can be performed only with the conductive member, the work is simplified.

  In addition, since one end of the conducting member is used as a contact part for the terminal on the apparatus main body side and the other end is used as a pressure contact part to the electronic component, the operation of inserting and mounting the developing device in the apparatus main body is performed at the contact part. The electrical connection between the terminal on the device body and the electronic component is ensured by ensuring that the electrical connection is ensured and the electrical connection relationship is reliably maintained by being pressed against the electronic component at the pressure contact part. Can be done reliably.

  In addition, a conductive member can be easily created by forming each part by deforming the wire such as bending the contact part or forming the pressure contact part in a coil shape. And it becomes possible to ensure electrical connection reliably and to further simplify the assembling work by press-contacting from both sides of the electronic component at the press-contact portion of the conductive member.

  Hereinafter, embodiments according to the present invention will be described in detail. The embodiments described below are preferable specific examples for carrying out the present invention, and thus various technical limitations are made. However, the present invention is particularly limited in the following description. Unless otherwise specified, the present invention is not limited to these forms.

  FIG. 1 is a schematic cross-sectional view of the entire image forming apparatus equipped with a developing device according to an embodiment of the present invention. A document reading unit 2 is arranged at the upper part of the image forming apparatus 1, and a paper feeding unit 3 and a recording unit 4 are arranged at the lower part from the bottom.

  In the document reading unit 2, the document placed on the document tray 11 provided on the document cover 10 is conveyed to the reading position by the document conveying device 12 and is discharged to the document discharge tray 13. At the reading position, a scanning device 16 equipped with a reading device 15 for optically reading a document is arranged so as to face the document. When reading a book or the like, the document cover 10 is rotated upward to place a read portion such as a book on the flat bed platen 14, and the scanning device 16 is moved in the sub-scanning direction as shown by an arrow. A reading operation is performed. The above-described configuration is the same as that of a conventional document reading apparatus called a so-called ADF or flat bed type.

  In the paper feed unit 3, a paper feed cassette 17 is disposed, and a plurality of sheets of a predetermined size are stacked on the flapper 18. A pickup roller 19 is disposed at the right end of the paper feed cassette 17. The flapper 18 is urged upward by a spring member (not shown) so that the upper surface of the stacked paper comes into pressure contact with the pickup roller 19. When the pickup roller 19 is rotationally driven in this state, the sheets are fed one by one to the sheet conveyance path by the frictional force.

  The fed paper is first conveyed to the recording unit 4 by the feed roller 20 and the press roller 21. The recording unit 4 includes a developing unit 22, a paper dust removing roller 23, a corona charger 24, a photosensitive drum 25, a transfer roller 26, an exposure head 27, and a fixing roller 28 for recording on the conveyed paper. Yes. The paper dust removing roller 23 is composed of a conductive sponge or the like, and supplements toner or paper dust attached to the surface of the photosensitive drum 25 after transfer. The corona charger 24 uniformly charges the surface of the photosensitive drum 25 by the discharge from the corotron. An electrostatic latent image is formed by exposing the photosensitive drum 23 uniformly charged by the paper dust removing roller 23 and the corona charger 24 according to the image recording signal by the exposure head 25. Then, as will be described later, the toner in the developing device 22 is transferred to the electrostatic latent image formed on the photosensitive drum 25 to visualize the electrostatic latent image. The transfer roller 26 is installed at a position facing the photosensitive drum 25 with the paper interposed therebetween, and a toner image formed on the surface of the photosensitive drum 25 is transferred to the paper when a predetermined voltage is applied. The transferred toner image is sandwiched between the fixing roller 28 and the press roller 29 and heated and pressed to be fixed on the paper. The fixed paper is sandwiched between the paper discharge roller 30 and the press roller 31 and is carried out to the paper discharge tray 32.

  In FIG. 1, a sheet conveyance path is indicated by a one-dot chain line from the sheet feeding unit 3 to the sheet discharge tray 32. A conveyance roller and a paper guide arranged along the paper conveyance path constitute a paper conveyance unit.

  A reversal conveyance unit 40 is detachably mounted on a side surface of the apparatus main body, and a paper carry-out port 41 and a paper carry-in port 42 are formed on the mounting side surface. In the transport unit 40, two pairs of transport rollers, a feed roller 43 and a press roller 44, and a feed roller 45 and a press roller 46, are arranged up and down. Then, as shown by a two-dot chain line in FIG. 1, the reverse conveyance path branches off from the sheet conveyance path between the paper discharge roller 30 and the fixing roller 28, and the two pairs of conveyance rollers 43 and 44, 45 and 46 are separated. It is formed so as to pass through and to join the paper conveyance path between the roller pairs 20 and 21 and the pickup roller 19.

  When recording on both sides of the sheet, the sheet is conveyed to the sheet conveyance path indicated by the one-dot chain line in FIG. 1 and recorded on one side, and then the sheet is carried out to the sheet discharge tray 32 by the discharge roller 30. The carry-out operation is temporarily stopped in a state where the rear end portion of the paper is sandwiched between the paper discharge roller 30 and the press roller 31. Then, the paper discharge roller 30 is driven to rotate reversely, the paper is carried into the reverse conveyance path from the rear end, and is nipped by the feed roller 43 and the press roller 44 to be conveyed in the reverse conveyance path. Next, the paper is nipped by the feed roller 45 and the press roller 46 and further conveyed, and the paper is brought into contact between the roller pair 20 and 21. When the sheet is conveyed to the sheet conveyance path in this state, the other surface is recorded to face the photosensitive drum 25, and recording is performed on both sides of the sheet.

  FIG. 2 is an enlarged cross-sectional view relating to the developing device 22. The developing device 22 is configured by sealing a lid 51 on the upper portion of the container body 50 by welding or fixing with screws. Three toner chambers 52, 53, and 54 are formed inside the container body 50 as toner replenishing chambers, and a supply chamber 57 having a developing roller 55 and a supply roller 56 at the side end on the photosensitive drum 25 side. Is formed. Paddles 58, 59, and 60 are provided as stirring transfer means at substantially the center of the three toner chambers 52, 53, and 54, respectively. In FIG. 2, assuming that the vertical direction of the paper surface is the front-rear direction of the developing device 22, the rotation shaft of each paddle is provided so that both ends in the front-rear direction are supported by the front-rear frame of the container body 50 and follow the front-rear direction It has been. A blade 61 made of a flexible resin film is attached to the tip of the paddle 60 so as to follow the rotational direction. Similarly, a blade 62 is attached to the paddle 59, and a blade 63 is attached to the paddle 60. The bottom surface of the container main body 50 is formed with sliding surface portions 64, 65, and 66 that are curved outward in an arcuate cross section so as to follow the trajectory of the rotation of the blade attached to each paddle.

  The toner supplied to each of the toner chambers 52 to 54 is stored in the sliding surface portions 64, 65, and 66. When the paddles 58, 59, 60 are rotated, the blades 61, 62, 63 are rotated so as to slide on the sliding surface portions 64, 65, 66, respectively. The toner is picked up by the sliding motion of each blade, and the toner is agitated in each toner chamber to prevent deterioration due to toner aggregation. Further, the blades 63, 64, 65 rotate counterclockwise, whereby the toner in each toner chamber is sequentially transferred to the supply chamber 57 and replenished. At that time, the replenished toner is agitated by the paddle 60 in the first toner chamber 52 and preliminarily charged.

  The toner replenished in the supply chamber 57 is rubbed and charged by slidingly contacting the developing roller 55 while the supply roller 56 rotates, and is carried on the surface of the developing roller 55. On the developing roller 55, a developing blade 67 that regulates the layer thickness of the supplied toner is disposed close to the surface of the developing roller 55.

  FIG. 3 shows an external view of the rear surface portion of the developing device 22 (the back side of the paper surface of the developing device 22 in FIG. 2). A rotation shaft 69 of the developing roller 55, a rotation shaft 70 of the supply roller 56, and a rotation shaft 71 of the paddles 60 to 62 are rotatably supported on the rear frame 68 of the container body 50. The end of each rotating shaft protrudes outward from the rear frame 68, and a drive transmission gear 72 is attached to the protruding portion, and the driving shaft 73 is connected to the driving mechanism on the apparatus main body side when the developing device 22 is mounted. Is transmitted to each rotary shaft by a transmission gear. A cover member 74 that covers a portion near the developing roller including the rotating shafts 69 and 70 is attached to the rear frame 68.

  FIG. 4 shows an enlarged view of the cover member 74 attached to the rear surface portion of the developing device 22. The cover member 74 is formed with a mounting hole 75 for screwing to the rear frame 68, and at positions corresponding to the rotation shaft 69 of the developing roller 55, the rotation shaft 70 of the supply roller, and the drive shaft 73, Circular openings 76, 77 and 78 are provided, respectively. On the back side of the cover member 74, there are a first contact member 79 that contacts the rotation shaft 69 of the developing roller 55, a second contact member 80 that contacts the rotation shaft 70 of the supply roller, and a blade that contacts the surface of the developing roller 55. A third contact member 82 that contacts the pressing plate 81 is attached.

  The first contact member 79 is made of a metal wire, and is bent in the center portion. One end is inserted and held in the holding portion 83 of the cover member 74. The holding portion 83 is formed so as to protrude stepwise toward the back surface side of the cover member 74, and a window for inserting the first contact member 79 is opened. The other end is bent in a U-shape to form a contact portion 84, which is engaged and fixed to a narrow insertion hole 85 and a circular engagement hole 86 formed in the cover member 74. ing. When attaching the contact portion 84 to the cover member 74, the contact portion 84 is first inserted into the insertion hole 85 from the back surface side, the contact portion 84 is brought out to the front surface side, and the bent tip portion is inserted into the engagement hole 86. By attaching the contact portion 84 in this way, the contact portion 84 is set in a state protruding from the surface side of the cover member 74, and can reliably contact and be electrically connected to the electrode of the image forming apparatus 1. Since the diameter of the engagement hole 86 is substantially the same as the diameter of the first contact member 79, the other end is firmly fixed, and one end is held by the holding portion 83. Thus, the first contact member 79 does not come out of the cover member 74. The first contact member 79 is in pressure contact with the rotating shaft 69 by the elastic force biased upward, and the first contact member 79 and the rotating shaft 69 can maintain a stable contact state and are electrically The connection state can be secured reliably.

  Similarly to the first contact member 79, the second contact member 80 is also made of a metal wire formed in a U-shape, and the other end is bent to form a U-shaped contact portion 87. One end of the second contact member 80 is inserted and held in the holding portion 88 provided in the same manner as the holding portion 83, and the contact portion 87 is provided in the cover member 74 in the same manner as the contact portion 84. Are engaged and fixed in a circular insertion hole 89 and a circular engagement hole 90. Accordingly, the second contact member 80 is securely held without coming out of the cover member 74 and the contact portion 87 is set in a state of protruding to the surface side of the cover member 74 so as to reliably contact the electrode of the image forming apparatus 1. Can be electrically connected. The second contact member 80 is in pressure contact with the rotating shaft 70 by an elastic force biased upward, and the second contact member 80 is in stable contact with the rotating shaft 70 in the same manner as the first contact member 79. The state can be maintained, and the electrical connection state can be reliably ensured.

  The third contact member 82 is made of a thin metal wire, one end is formed in a coil spring shape, the other end is bent in an L shape at a right angle to form a contact portion 91, and the tip is Furthermore, it is bent into a bowl shape. When attaching the third contact member 82 to the cover member 74, the other end portion is inserted into the circular insertion hole 92 provided in the cover member 74 from the back surface side so that the contact portion 91 is on the front surface side of the cover member 74. The bent portion at the tip is inserted into the circular engagement hole 93 and fixed. Since the diameter of the engagement hole 93 is formed substantially the same as the diameter of the third contact member 82, the other end is firmly fixed. Therefore, the third contact member 82 is securely held without coming out of the cover member 74, and the contact portion 91 is set in a state of projecting to the front surface side of the cover member 74 and reliably contacts the electrode of the image forming apparatus 1. Can be electrically connected. Further, the portion formed in the shape of a coil spring at one end is held in a compressed state in contact with the end of the pressing plate 81 of the blade when the cover member 74 is attached to the rear frame 68. . Therefore, a stable contact state with the pressing plate 81 can be maintained, and the electrical connection state can be ensured.

  The cover member 74 is provided with a fourth contact member 94 and a fifth contact member 95 for identifying the developing device 22. The cover member 74 is formed with a housing recess 97 for housing the fuse tube 96, and the housing recess 97 is sealed by a lid member 98.

  FIG. 5 is an enlarged view showing a mounted state of the fourth contact member 94, the fifth contact member 95, and the fuse tube 96, and FIG. 6 is a perspective view showing an assembled state of the fourth contact member 94 and the fifth contact member 95. FIG. The fourth contact member 94 is made of a thin metal wire and has a spring property. A substantially central portion of the fourth contact member 94 is bent in a bowl shape, one is inserted on the back side of the lid member 98, and the other is exposed on the front side of the cover member 74. One end 99 inserted on the back side of the lid member 98 is formed in a coil shape, and the other end 100 exposed on the front side of the cover member 74 is bent and provided on the cover member 107. It is inserted into the narrow insertion hole 101 and locked to the back side of the cover member 74. When the cover member 74 is provided with an insertion hole 102 similar to the insertion hole 101 and the length of the fourth contact member 94 is short, the bent portion of the other end 100 is inserted as shown in FIG. It is inserted into the hole 102.

  The fifth contact member 95 is made of a thin metal wire similar to the fourth contact member 94 and has a spring property. The fifth contact member 95 has a central portion bent like a hook like the fourth contact member 94 and is inserted into the back side of the lid member 98, and one end 103 is formed in a coil shape. Yes. The other end is exposed on the surface side of the cover member 74, and the other end 104 is bent into a hook shape and inserted into a narrow insertion hole 105 provided in the cover member 74 to be locked. Yes.

  One end 99 of the fourth contact member 94 is inserted and held by a locking bar 106 protruding from the side surface in the housing recess 97, and one end 103 of the fifth contact member 95 is It is inserted and held in a locking bar 107 that is arranged to face the locking bar 106 and protrudes from the side surface of the housing recess 97. Therefore, the end portions 99 and 103 formed in a coil shape are arranged to face each other, and the fuse tube 96 is pressed and held therebetween.

    When the developing device 22 is attached to the apparatus main body, as shown in FIG. 5, the two connection terminals 108 a and 108 b on the apparatus main body abut against the fourth contact member 94. The connection terminal 108a is disposed in contact with the insertion hole 1102 and the connection terminal 108b is disposed in contact with the insertion hole 101. When the fourth contact member 94 has a length up to the insertion hole 101, both are provided. The connection terminal contacts the fourth contact member 94, but only the connection terminal 108a contacts the fourth contact member 94 in the case of a short length to the insertion hole 102 as shown in FIG. Further, the connection terminal 108 c on the apparatus main body side is in contact with the fifth contact member 95 in the vicinity of the insertion hole 105.

  Accordingly, a state in which the developing device 22 is mounted and the connection terminal on the apparatus main body abuts is shown in a circuit diagram as shown in FIG. The connection terminal 108a is set to the ground potential, and the presence / absence of conduction between the connection terminals 108a and 108b is detected. When the conduction is detected, the fourth contact member 94 is inserted into the insertion hole 101. It is identified that the fourth contact member 94 is short to the insertion hole 102 when it is not conductive. Therefore, the type of the developing device 22 can be identified by changing the length of the fourth contact member 94 attached according to the type of the developing device 22. In addition, if a current sufficient to melt the fuse tube 96 is passed between the connection terminals 108a and 108c, the fuse tube 96 is cut when the developing device 22 is mounted. Therefore, the developing device attached to the apparatus main body is not electrically connected between the connection terminals 108a and 108c, and if the presence or absence of the connection between the connection terminals 108a and 108c is detected, the developing device 22 is new or used. Can be identified.

  As described above, since the fourth contact member and the fifth contact member can be formed from a single spring-like wire, the conducting member can be formed with a simple structure. In addition, as for the assembly, it is only necessary to insert one end portion into the locking bar and insert the other end into the insertion hole to be locked. And it becomes possible to position a contact member reliably in a predetermined position. In addition, since the coil-shaped portions are arranged to face each other and are held in pressure contact from both sides of the fuse tube, which is an electronic component, the electronic component can be easily mounted and the fuse tube and the contact member The electrical connection state between them can be maintained in a stable state.

1 is a schematic sectional view of an entire image forming apparatus according to an embodiment of the present invention. It is an expanded sectional view regarding a developing device. It is an external view regarding the rear surface part of a developing device. It is an enlarged view regarding the electrical connection structure of a developing device. It is an enlarged view which shows the mounting state of a contact member and a fuse pipe | tube. It is a disassembled perspective view which shows the case where a contact member is assembled | attached. It is an enlarged view which shows the attachment state of a contact member with a short length, and a fuse tube. It is a circuit diagram which shows the electrical connection relation of a contact member and a fuse pipe | tube.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Image forming apparatus 2 Document reading part 3 Paper feed part 4 Recording part
22 Developer
25 Photosensitive drum
50 Container body
51 lid
55 Developing roller
94 Fourth contact member
95 Fifth contact member
96 fuse tube

Claims (5)

  The developing device inserted and mounted inside the image forming apparatus includes a conductive member made of a metal wire material that contacts a terminal disposed on the apparatus main body side when mounted, and the conductive member has one end. The developing unit is characterized in that the portion is formed at a contact portion with respect to the terminal and the other end portion is formed at a pressure contact portion electrically connected to the electronic component.   The developing device according to claim 1, wherein the contact portion of the conducting member is formed by being bent.   The developing device according to claim 1, wherein the pressure contact portion of the conducting member is formed in a coil shape.   4. The developing device according to claim 1, wherein the electronic component is held by press contact portions of the conducting member being pressed from both sides to terminals at both ends of the electronic component. 5.   5. The developing device according to claim 1, wherein the electronic component is a fuse used for identifying whether the developing device is a new product or a used product. 6.

Images