Patent Publication Number: US-9836016-B2

Title: Image forming apparatus and cartridge

Description:
BACKGROUND OF THE INVENTION 
     Field of the Invention 
     The present invention relates to an image forming apparatus which uses an electrophotographic technique and a cartridge capable of being detachably attached to the image forming apparatus. 
     Description of the Related Art 
     In an image forming operation of an image forming apparatus which uses an electrophotographic technique, first, a photosensitive drum is uniformly charged by a charging roller. Moreover, the charged photosensitive drum is selectively exposed by an exposure device, whereby an electrostatic latent image is formed on the photosensitive drum. The electrostatic latent image formed on the photosensitive drum is developed by a developing apparatus as a toner image. 
     Moreover, the toner image formed on the photosensitive drum is transferred to a sheet by a transfer roller. The toner image transferred to the sheet is pressurized and heated by a fixing device whereby the toner image is fixed to the sheet. The image forming apparatus forms an image on the sheet in this manner. 
     In the image forming apparatus, in general, replenishment of toner and maintenance of means for forming an image on the sheet (process means) or the like are required. 
     In recent years, in order to perform such maintenance and the like easily, the photosensitive drum, the charging roller, the developing apparatus, and the like are integrated as a cartridge. A cartridge in which the photosensitive drum and the like are integrated is called a process cartridge and is detachably attached to an image forming apparatus body. 
     In such a cartridge, electrical terminals (cartridge-side terminals) for supplying voltage to process means such as the charging roller are provided. In a state in which the cartridge is attached to the image forming apparatus body, the cartridge-side terminals are electrically connected to electrical terminals (body-side terminals) provided on the image forming apparatus body. Here, when a foreign material adheres to the cartridge-side terminal, an electrical connection state between the cartridge and the image forming apparatus body may become unstable. 
     Thus, a configuration in which a shutter for covering the cartridge-side terminals is provided in a cartridge is proposed (Japanese Patent Application Publication No. 2005-128469). In a state in which the cartridge is detached from an image forming apparatus body, the shutter covers the cartridge-side terminals. Moreover, the shutter rotates in synchronization with an operation of attaching the cartridge to the image forming apparatus body whereby the shutter exposes the cartridge-side terminals. 
     However, in this configuration, since it is necessary to provide a mechanism for rotating the shutter in the cartridge, the number of components that form the cartridge increases. In addition, the increase in the number of components increases the cost of manufacturing the cartridge. 
     SUMMARY OF THE INVENTION 
     An object of the present invention is to provide an image forming apparatus comprising an apparatus body and a cartridge capable of being detachably attached to the apparatus body, wherein 
     the apparatus body includes an elastic body-side terminal, which is a terminal for supplying electricity to the cartridge, 
     the cartridge includes: 
     a developing apparatus that develops as a developer image an electrostatic latent image formed on an image bearing member; 
     a cartridge-side terminal for supplying electricity from the apparatus body; and 
     a frame having an opening that exposes the cartridge-side terminal, 
     in a process of attaching the cartridge to the apparatus body, the body-side terminal makes contact with the cartridge-side terminal by being inserted into the opening, and 
     the body-side terminal presses the cartridge-side terminal in a state in which the cartridge is attached to the apparatus body. 
     Another object of the present invention is to provide a cartridge capable of being detachably attached to an apparatus body of an image forming apparatus, comprising: 
     a developing apparatus that develops as a developer image an electrostatic latent image formed on an image bearing member; 
     a cartridge-side terminal, which is a terminal for supplying electricity from the apparatus body to the cartridge; and 
     a frame having an opening that exposes the cartridge-side terminal and into which a terminal provided on the apparatus body is inserted when the cartridge is attached to the apparatus body. 
     Further features of the present invention will become apparent from the following description of exemplary embodiments (with reference to the attached drawings). 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a schematic cross-sectional view of an image forming apparatus according to a first embodiment; 
         FIG. 2  is a schematic cross-sectional view of a process cartridge according to the first embodiment; 
         FIG. 3  is a diagram illustrating a configuration of the process cartridge according to the first embodiment; 
         FIG. 4  is a diagram illustrating a configuration of the process cartridge according to the first embodiment; 
         FIG. 5  is a perspective view of an apparatus body of the image forming apparatus according to the first embodiment; 
         FIG. 6  is a diagram illustrating a state in which a process cartridge is to be attached to an image forming apparatus body; 
         FIGS. 7A and 7B  are diagrams illustrating a portion near the cartridge-side electrical terminals of the process cartridge; 
         FIG. 8  is a side view of the process cartridge according to the first embodiment; and 
         FIG. 9  is a side view of a process cartridge according to a second embodiment. 
     
    
    
     DESCRIPTION OF THE EMBODIMENTS 
     Hereinafter, exemplary embodiments of the present invention will be described with reference to the accompanying drawings. However, dimensions, materials, shapes, relative positions, and the like of constituent components described in the embodiment are changed appropriately according to, for example, a configuration and various conditions of an apparatus to which the present invention is applied. That is, the scope of the present invention is not limited to the following embodiments. 
     First Embodiment 
     &lt;Overall Configuration of Image Forming Apparatus&gt; 
     A first embodiment will be described.  FIG. 1  is a schematic cross-sectional view of an image forming apparatus  1  according to the first embodiment. Here, an axial direction of the center of rotation of a photosensitive drum  62  (an image bearing member) is defined as a longitudinal direction. In this longitudinal direction, a side on which the photosensitive drum  62  receives the driving force from an apparatus body A of the image forming apparatus  1  is defined as a driving side, and the opposite side of the driving side is defined as a non-driving side. Here, the apparatus body A of the image forming apparatus  1  is a portion of the image forming apparatus  1  excluding a cartridge B (a process cartridge). The image forming apparatus  1  is a laser beam printer which uses an electrophotographic technique. In the image forming apparatus  1 , the cartridge B is configured to be detachably attached to the apparatus body A. Moreover, a sheet tray  4  that stores a recording medium (hereinafter referred to as a sheet material P) on which an image is formed is disposed on a lower side of the cartridge B. 
     In the apparatus body A of the image forming apparatus  1 , a pickup roller  5   a , a feed roller pair  5   b , a conveying roller pair  5   c , a transfer guide  6 , a transfer roller  7 , a conveying guide  8 , a fixing device  9 , a discharge roller pair  10 , and a discharge tray  11  are sequentially disposed in a conveying direction D of the sheet material P. The fixing device  9  includes a heating roller  9   a  and a pressure roller  9   b.    
     &lt;Image Forming Process&gt; 
     Next, an image forming process will be described. First, when the image forming apparatus  1  receives a print start signal, the photosensitive drum  62  is driven to rotate in the direction indicated by arrow R in  FIG. 1 . A charging roller  66  (a charging member) (see  FIG. 2 ) to which a bias voltage is applied uniformly charges an outer circumferential surface of the photosensitive drum  62  by making contact with the outer circumferential surface of the photosensitive drum  62 . An exposure device  3  outputs a laser beam L to the photosensitive drum  62  according to image information. The laser beam L passes through a gap between a developing container  23  and a cleaning frame  71  of the cartridge B and scans and exposes the outer circumferential surface of the photosensitive drum  62 . In this way, an electrostatic latent image corresponding to the image information is formed on the outer circumferential surface of the photosensitive drum  62 . 
     On the other hand, as illustrated in  FIG. 2 , in a developing unit  20  (a developing apparatus), toner T in a toner chamber  29  is delivered to a toner supply chamber  28  by being stirred and conveyed when a first conveying member  43 , a second conveying member  44 , and a third conveying member  50  rotate. The toner T delivered to the toner supply chamber  28  is borne on a surface of a developing roller  32  (a developer bearing member) by the magnetic force of a magnet roller  34  (a fixed magnet). The toner T borne on the developing roller  32  is triboelectrically charged by the developing blade  42  and the thickness of the toner T borne on the developing roller  32  is regulated to a constant thickness. The toner T borne on the developing roller  32  is supplied to the photosensitive drum  62 , whereby the electrostatic latent image formed on the photosensitive drum  62  is developed as a toner image (a developer image). 
     Moreover, as illustrated in  FIG. 1 , the sheet material P stored in a lower portion of the apparatus body A is fed from the sheet tray  4  by the pickup roller  5   a , the feed roller pair  5   b , and the conveying roller pair  5   c  in synchronization with the timing at which the laser beam L is output. Moreover, the sheet material P is guided to the transfer guide  6  and is conveyed to a transfer position which is a nip portion between the photosensitive drum  62  and the transfer roller  7 . At this transfer position, the toner image is transferred from the photosensitive drum  62  to the sheet material P. 
     The sheet material P to which the toner image is transferred is guided to the conveying guide  8  and is conveyed to the fixing device  9 . Moreover, the sheet material P passes through the nip portion between the heating roller  9   a  and the pressure roller  9   b  of the fixing device  9 . At this nip portion, the sheet material P is pressurized and heated whereby the toner image is fixed to the sheet material P. The sheet material P to which the toner image is fixed is discharged to the discharge tray  11  by the discharge roller pair  10 . On the other hand, as illustrated in  FIG. 2 , the toner remaining on the photosensitive drum  62  after the toner image is transferred is removed by a cleaning member  77 . The removed toner is used again to form a toner image. The toner removed from the photosensitive drum  62  is stored in a waste toner chamber  71   b  of a cleaning unit  60 . 
     &lt;Overall Configuration of Cartridge B&gt; 
     Next, an overall configuration of the cartridge B will be described with reference to  FIGS. 2 to 4 .  FIG. 2  is a schematic cross-sectional view of the cartridge B according to the first embodiment.  FIG. 3  is a diagram illustrating a configuration of the cartridge B according to the first embodiment.  FIG. 4  is a diagram illustrating a configuration of the cartridge B according to the first embodiment. In the present embodiment, description of screws for coupling respective components will not be provided. 
     The cartridge B according to the present embodiment will be described with reference to  FIG. 2 . The cartridge B includes the cleaning unit  60  and the developing unit  20 . In general, a process cartridge is a cartridge in which a photosensitive drum is integrated with at least one of a charging means and a cleaning means which are process means acting on the photosensitive drum. Moreover, the process cartridge is configured to be detachably attached to an apparatus body of an image forming apparatus. 
     The cleaning unit  60  includes the photosensitive drum  62 , the charging roller  66 , the cleaning member  77 , the cleaning frame  71  supporting these components, and a lid member  72  fixed to the cleaning frame  71  by welding or the like. The charging roller  66  and the cleaning member  77  are disposed so as to make contact with the outer circumferential surface of the photosensitive drum  62 . The cleaning member  77  includes a rubber blade member  77   a  having a blade shape and formed of rubber which is an elastic member and a supporting member  77   b  that supports the rubber blade member  77   a.    
     The rubber blade member  77   a  is in abutting contact with the photosensitive drum  62  in a counter direction relative to the rotation direction of the photosensitive drum  62 . That is, the rubber blade member  77   a  is in abutting contact with the photosensitive drum  62  so that the distal end of the rubber blade member  77   a  faces the upstream side in the rotation direction of the photosensitive drum  62 . The toner removed from the surface of the photosensitive drum  62  by the cleaning member  77  is conveyed to the waste toner chamber  71   b  including the cleaning frame  71  and the lid member  72  by a waste toner conveying member  54 . The waste toner conveying member  54  engages with a crank member  86 . When driving force is transmitted from the crank member  86  to the waste toner conveying member  54 , the waste toner conveying member  54  rotates in the direction indicated by arrow Q in  FIG. 2  to convey toner to the waste toner chamber  71   b.    
     Moreover, a scooping sheet  65  for preventing leakage of toner from the waste toner chamber  71   b  is formed at the edge of the cleaning frame  71  so as to make abutting contact with the photosensitive drum  62 . Moreover, when driving force of a body driving motor (not illustrated) which is a driving source is transmitted to the photosensitive drum  62 , the photosensitive drum  62  rotates in the direction indicated by arrow R in  FIG. 2  according to an image forming operation. The charging roller  66  is attached near both ends in the longitudinal direction (the direction approximately parallel to the axial direction of the center of rotation of the photosensitive drum  62 ) of the cleaning frame  71  so as to be rotatable with the aid of a charging roller bearing  67 . A biasing member  68  presses the charging roller bearing  67  toward the photosensitive drum  62 , whereby the charging roller  66  presses the photosensitive drum  62 . Moreover, the charging roller  66  rotates following the rotation of the photosensitive drum  62 . 
     The developing unit  20  includes the developing roller  32 , the developing container  23  that supports the developing roller  32 , the developing blade  42 , and the like. The magnet roller  34  is provided inside the developing roller  32 . Moreover, the developing blade  42  regulates the thickness of a toner layer borne on the developing roller  32 . An interval maintaining member  38  is attached to both ends of the developing roller  32  in the axial direction of the center of rotation of the developing roller  32 . The interval maintaining member  38  makes abutting contact with the photosensitive drum  62  to form a small gap between the developing roller  32  and the photosensitive drum  62 . 
     Moreover, a blowout preventing sheet  33  for preventing toner from blowing out from the developing unit  20  is attached to the edge of a bottom member  22  so as to make abutting contact with the developing roller  32 . Further, the first, second, and third conveying members  43 ,  44 , and  50  are provided in the toner chamber  29  formed by the developing container  23  and the bottom member  22 . The first, second, and third conveying members  43 ,  44 , and  50  stir and convey the toner stored in the toner chamber  29  to the toner supply chamber  28 . 
     As illustrated in  FIGS. 3 and 4 , the cartridge B is configured by coupling the cleaning unit  60  and the developing unit  20 . A drum bearing  73  that rotatably supports the photosensitive drum  62 , the cleaning frame  71 , the lid member  72 , the photosensitive drum  62 , and a drum shaft  78  are provided in the cleaning unit  60 . A driving-side drum flange  63  provided on the driving side is inserted into a hole  73   a  of the drum bearing  73  whereby the photosensitive drum  62  is rotatably supported. Moreover, on the non-driving side (see  FIG. 4 ), the drum shaft  78  is press-fitted to a hole  71   c  formed in the cleaning frame  71  to rotatably support a hole (not illustrated) of a non-driving-side drum flange  64 . Moreover, a flange gear portion  63   b  that transmits the driving force to a developing roller gear  39  provided on the driving side of the developing roller  32  is provided in the driving-side drum flange  63 . 
     A driving-side drum side member  69  and a non-driving-side drum side member  70  for supporting the developing unit  20  are provided on both end sides of the cleaning frame  71 . A boss  71   a  provided on the driving side of the cleaning frame  71  is inserted into a long hole  69   d  formed in the driving-side drum side member  69 . Moreover, a supporting portion  73   b  of the drum bearing  73  attached to the cleaning frame  71  is inserted into a positioning hole  69   c  formed in the driving-side drum side member  69 . In this way, the driving-side drum side member  69  is fixed to the cleaning frame  71 . 
     A boss  71   d  formed on the non-driving side of the cleaning frame  71  is inserted into a long hole  70   d  formed in the non-driving-side drum side member  70 . Moreover, an outer diameter portion  71   e  of a cylindrical boss in which the drum shaft  78  is inserted is inserted into a positioning hole  70   c  formed in the non-driving-side drum side member  70 . In this way, the non-driving-side drum side member  70  is fixed to the cleaning frame  71 . 
     On the other hand, the developing unit  20  includes the bottom member  22  (see  FIG. 1 ), the developing container  23  (see  FIG. 1 ), a driving-side developing side member  26 , a non-driving-side developing side member  27 , the developing roller  32 , and the developing blade  42 . The developing roller  32  is rotatably attached to the developing container  23  with bearing members  37  provided on both end sides of the developing roller  32  interposed. Moreover, the driving-side drum side member  69  and the non-driving-side drum side member  70  are slidably coupled whereby the developing unit  20  and the cleaning unit  60  are coupled. The cartridge B includes the developing unit  20  and the cleaning unit  60 . 
     On one end side in the longitudinal direction of the developing unit  20 , a first developing supporting portion  26   a  and a second developing supporting portion  26   b  are formed on the driving-side developing side member  26 . Moreover, on the other end side in the longitudinal direction of the developing unit  20 , a third developing supporting portion  27   a  and a fourth developing supporting portion  27   b  are formed on the non-driving-side developing side member  27 . Moreover, the first developing supporting portion  26   a  formed on the driving-side developing side member  26  is inserted into a first long hole  69   a  formed in the driving-side drum side member  69 . The second developing supporting portion  26   b  formed on the driving-side developing side member  26  is inserted into a second long hole  69   b  formed in the driving-side drum side member  69 . 
     Moreover, the third developing supporting portion  27   a  formed on the non-driving-side developing side member  27  is inserted into a third long hole  70   a  formed in the non-driving-side drum side member  70 . The fourth developing supporting portion  27   b  formed on the non-driving-side developing side member  27  is inserted into a fourth long hole  70   b  formed in the non-driving-side drum side member  70 . In this manner, the driving-side drum side member  69  and the non-driving-side drum side member  70  are coupled whereby the developing unit  20  and the cleaning unit  60  are coupled. 
     Moreover, a first engagement portion  46 Ra of a driving-side biasing member  46 R is attached to a boss  69   e  of the driving-side drum side member  69 . A second engagement portion  46 Rb of the driving-side biasing member  46 R is attached to a boss  26   c  of the driving-side developing side member  26 . Moreover, a first engagement portion  46 Fa of a non-driving-side biasing member  46 F is attached to a boss  70   e  of the non-driving-side drum side member  70 . A second engagement portion  46 Fb of the non-driving-side biasing member  46 F is caught at a boss  27   c  of the non-driving-side developing side member  27 . 
     In the present embodiment, the driving-side biasing member  46 R and the non-driving-side biasing member  46 F are metallic tension springs and are configured to press the developing unit  20  against the cleaning unit  60  with the biasing force of the spring. Due to this, the developing roller  32  is reliably pressed toward the photosensitive drum  62 . Moreover, due to the interval maintaining member  38  attached to both ends of the developing roller  32 , a predetermined interval is formed between the developing roller  32  and the photosensitive drum  62 . 
     &lt;Cartridge Attachment and Detachment Operation&gt; 
       FIG. 5  is a perspective view of the apparatus body A of the image forming apparatus  1  according to the first embodiment. Moreover,  FIG. 6  is a diagram illustrating a state in which the cartridge B is to be attached to the apparatus body A of the image forming apparatus  1 . Next, an operation of attaching and detaching the cartridge B to and from the apparatus body A of the image forming apparatus  1  will be described with reference to  FIGS. 5 and 6 . 
     An opening door  13  is pivotably attached to the apparatus body A. When a user opens the opening door  13 , a cartridge attachment opening  17  formed in a non-driving sideboard  16  of the apparatus body A is exposed. Moreover, a cartridge guide  12  that guides the cartridge B into the apparatus body A is formed inside the cartridge attachment opening  17  of the apparatus body A. The cartridge B is guided to the cartridge guide  12  and inserted into the apparatus body A in the direction indicated by arrow C in  FIG. 6 . 
     Here, the direction indicated by arrow C is the axial direction of the center of rotation of the photosensitive drum  62  and the direction in which the cartridge B is inserted into the apparatus body A from the non-driving side to the driving side. That is, the non-driving side is on the upstream side and the driving side is on the downstream side in the direction in which the cartridge B is inserted into the apparatus body A. A driving shaft  14  that transmits driving force to a driving force receiver  63   a  (see  FIG. 3 ) provided in the cartridge B is provided in the apparatus body A. 
     The driving shaft  14  is driven by a motor (not illustrated) provided in the apparatus body A. Due to this, the photosensitive drum  62  coupled to the driving force receiver  63   a  rotates by receiving driving force from the apparatus body A. Further, electric power is supplied to the charging roller  66  via an upstream-side charging terminal  91  (a body-side terminal) (see  FIGS. 7A and 7B ) formed on the apparatus body A. Moreover, electric power is supplied to the developing roller  32  via an upstream-side developing terminal  90  (a body-side terminal) (see  FIGS. 7A and 7B ) formed on the apparatus body A. 
     &lt;Description of Electrical Terminal&gt; 
       FIGS. 7A and 7B  are diagrams illustrating a portion near the cartridge-side electrical terminals of the process cartridge B.  FIG. 8  is a side view of the cartridge B according to the first embodiment. The configuration of the apparatus body A of the image forming apparatus  1  and the electrical terminals of the cartridge B will be described with reference to  FIGS. 7A and 7B  and  FIG. 8 .  FIG. 7A  is a diagram illustrating a state immediately before the cartridge B is attached to the apparatus body A.  FIG. 7B  is a cross-sectional view illustrating a state in which the cartridge B is attached to the apparatus body A.  FIG. 7B  is taken along a plane S 1  in  FIG. 7A . 
     As illustrated in  FIG. 7A , a downstream-side developing terminal  79  (a first cartridge-side terminal) for supplying electricity from the apparatus body A to the developing roller  32  is formed on a side surface of the cartridge B. Electricity is supplied from the apparatus body A to the developing roller  32  via the downstream-side developing terminal  79 . Moreover, a downstream-side charging terminal  80  (a second cartridge-side terminal) for supplying electricity from the apparatus body A to the charging roller  66  is formed on the side surface of the cartridge B. Electricity is supplied from the apparatus body A to the charging roller  66  via the downstream-side charging terminal  80 . 
     Moreover, the downstream-side developing terminal  79  and the downstream-side charging terminal  80  are formed of a metal plate. The downstream-side developing terminal  79  has a connection surface  79   a  which is a surface orthogonal to the direction of attaching and detaching the cartridge B (C direction). Moreover, the downstream-side charging terminal  80  has a connection surface  80   a  which is a surface orthogonal to the direction of attaching and detaching the cartridge B (C direction). The downstream-side developing terminal  79  is electrically connected to the developing roller  32  via an electrical path (not illustrated). Moreover, the downstream-side charging terminal  80  is electrically connected to the charging roller  66  via an electrical path (not illustrated). 
     A hole-shaped opening  69   f  is formed in the driving-side drum side member  69  (a frame) at a position corresponding to the downstream-side developing terminal  79 . Moreover, a hole-shaped opening  69   g  is formed in the driving-side drum side member  69  at a position corresponding to the downstream-side charging terminal  80 . The opening  69   f  exposes the downstream-side developing terminal  79 . Moreover, the opening  69   g  exposes the downstream-side charging terminal  80 . Moreover, the downstream-side developing terminal  79  is disposed near an edge of the opening  69   f  on the opposite side from an edge on a side on which insertion of the upstream-side developing terminal  90  starts. That is, the downstream-side developing terminal  79  is disposed so as to be able to make contact with the upstream-side developing terminal  90  after the upstream-side developing terminal  90  passes through the opening  69   f . Moreover, the downstream-side charging terminal  80  is disposed near an edge of the opening  69   g  on the opposite side from a side on which insertion of the upstream-side charging terminal  91  starts. That is, the downstream-side charging terminal  80  is disposed so as to be able to make contact with the upstream-side charging terminal  91  after the upstream-side charging terminal  91  passes through the opening  69   g.    
     The upstream-side developing terminal  90  which is an electrical terminal formed of a spring wire or the like having elasticity is formed on the apparatus body A at the position corresponding to the downstream-side developing terminal  79 . In a state in which the cartridge B is attached to the apparatus body A, the upstream-side developing terminal  90  presses the downstream-side developing terminal  79 . Moreover, the upstream-side charging terminal  91  which is an electrical terminal formed of a spring wire or the like having elasticity is formed on the apparatus body A at the position corresponding to the downstream-side charging terminal  80 . In a state in which the cartridge B is attached to the apparatus body A, the upstream-side charging terminal  91  presses the downstream-side charging terminal  80 . 
     The upstream-side developing terminal  90  is supported by a developing terminal supporting member  92  which is a cylindrical supporting member formed of a resin. Moreover, the upstream-side charging terminal  91  is supported by a charging terminal supporting member  93  which is a cylindrical supporting member formed of a resin. In the process in which the cartridge B is inserted into the apparatus body A, the developing terminal supporting member  92  enters into the opening  69   f  and the charging terminal supporting member  93  enters into the opening  69   g.    
     Moreover, as illustrated in  FIG. 7B , when the cartridge B is completely attached to the apparatus body A, the upstream-side developing terminal  90  makes abutting contact with the connection surface  79   a  of the downstream-side developing terminal  79 . Moreover, when the cartridge B is completely attached to the apparatus body A, the upstream-side charging terminal  91  makes abutting contact with the connection surface  80   a  of the downstream-side charging terminal  80 . Moreover, when the upstream-side developing terminal  90  makes abutting contact with the connection surface  79   a , the upstream-side developing terminal  90  is elastically deformed. Moreover, when the upstream-side charging terminal  91  makes abutting contact with the connection surface  80   a , the upstream-side charging terminal  91  is elastically deformed. 
     Moreover, by the restoring force of the spring occurring in the upstream-side developing terminal  90 , the upstream-side developing terminal  90  presses the downstream-side developing terminal  79 . As a result, the downstream-side developing terminal  79  and the upstream-side developing terminal  90  are electrically connected. Moreover, by the restoring force occurring in the upstream-side charging terminal  91 , the upstream-side charging terminal  91  presses the downstream-side charging terminal  80 . As a result, the downstream-side charging terminal  80  and the upstream-side charging terminal  91  are electrically connected. 
     In the present embodiment, in a state in which the cartridge B is detached from the apparatus body A, the downstream-side developing terminal  79  is positioned on the inner side of the opening  69   f  of the driving-side drum side member  69 . Thus, in the state in which the cartridge B is detached from the apparatus body A, it is less likely that a user touches the downstream-side developing terminal  79  mistakenly. Moreover, in the state in which the cartridge B is detached from the apparatus body A, the downstream-side charging terminal  80  is positioned on the inner side of the opening  69   g  of the driving-side drum side member  69 . Thus, in the state in which the cartridge B is detached from the apparatus body A, it is less likely that a user touches the downstream-side charging terminal  80  mistakenly. 
     Moreover, in the present embodiment, in the state in which the cartridge B is detached from the apparatus body A, it is less likely that the downstream-side developing terminal  79  and the downstream-side charging terminal  80  make contact with components provided on the apparatus body A. Due to this, it is possible to reduce the risk that a foreign material adheres to the downstream-side developing terminal  79  and the downstream-side charging terminal  80 . In this way, it is possible to improve the accuracy of the electrical connection between the apparatus body A and the cartridge B. 
     Moreover, in the present embodiment, as illustrated in  FIG. 8 , in the state in which the cartridge B is attached to the apparatus body A, a gap is formed between an end surface of the opening  69   f  of the cartridge B and the developing terminal supporting member  92  of the apparatus body A. That is, the developing terminal supporting member  92  does not overlap the driving-side drum side member  69 , but the entire opening  69   f  is exposed. Moreover, in the state in which the cartridge B is attached to the apparatus body A, a gap is formed between an end surface of the opening  69   g  of the cartridge B and the charging terminal supporting member  93  of the apparatus body A. That is, the charging terminal supporting member  93  does not overlap the driving-side drum side member  69 , but the entire opening  69   g  is exposed. This gap is set to be larger than the distance that the cartridge B can move relative to the apparatus body A in the direction orthogonal to the direction of inserting the cartridge B into the apparatus body A. Due to this, the movement of the cartridge B in relative to the apparatus body A is not restricted by the openings  69   f  and  69   g.    
     As described above, in the present embodiment, the cartridge-side terminal which is an electrical terminal for supplying electricity from the apparatus body A of the image forming apparatus  1  to the cartridge B (the process cartridge) is exposed by the opening formed in the frame. Since the cartridge-side terminal is positioned in the opening, the user rarely touches the cartridge-side terminal. Due to this, a foreign material rarely adheres to the cartridge-side terminal. Thus, it is possible to maintain a satisfactory electrical connection state between the cartridge B and the apparatus body A without providing complex mechanisms. 
     Second Embodiment 
     A second embodiment will be described. Here, in the second embodiment, portions having the same functions as those of the first embodiment will be denoted by the same reference numerals as used in the first embodiment and the description thereof will not be provided.  FIG. 9  is a side view of a process cartridge according to the second embodiment. In the first embodiment, in the state in which the cartridge B is attached to the apparatus body A, a gap is formed between the end surface of the opening  69   f  and the developing terminal supporting member  92  and between the end surface of the opening  69   g  and the charging terminal supporting member  93 . In the first embodiment, this gap is formed so that the movement of the cartridge B in relative to the apparatus body A is not restricted. 
     In the second embodiment, an opening  169   f  formed in a driving-side drum side member  169  has a different shape from the opening  69   f  formed in the driving-side drum side member  69  according to the first embodiment. Moreover, an opening  169   g  formed in a driving-side drum side member  169  has a different shape from the opening  69   g  formed in the driving-side drum side member  69 . Thus, in the second embodiment, the gap between the opening  169   f  and the developing terminal supporting member  92  and the gap between the opening  169   g  and the charging terminal supporting member  93  are different from those of the first embodiment. 
     A method of positioning a cartridge C relative to the apparatus body A will be described with reference to  FIG. 9 . Similarly to the first embodiment, in the cartridge C the supporting portion  73   b  is provided in the drum bearing  73 . Moreover, the boss  71   a  is provided on the cleaning frame  71 . On the other hand, a positioning hole  94  having abutting portions  94   a  and  94   b  and a rotation stopping hole  95  having an abutting portion  95   a  are formed in the apparatus body A. Moreover, a pressing means (not illustrated) that generates pressing force E of pressing the supporting portion  73   b  is provided in the apparatus body A. By the weight of the cartridge C and the pressing force E, the supporting portion  73   b  abuts on the abutting portions  94   a  and  94   b  of the positioning hole  94 . Moreover, by the weight of the cartridge C and the pressing force E, the boss  71   a  abuts on the abutting portion  95   a  of the rotation stopping hole  95 . 
     In this state, in a horizontal direction in an attitude in which the image forming apparatus is normally used, a gap L 1   a  is formed between the supporting portion  73   b  and the positioning hole  94 . Moreover, in a vertical direction in an attitude in which the image forming apparatus is normally used, a gap L 1   b  is formed between the supporting portion  73   b  and the positioning hole  94 . Further, in the horizontal direction in an attitude in which the image forming apparatus is normally used, a gap L 2   a  is formed between the boss  71   a  and the rotation stopping hole  95 . 
     Moreover, in the vertical direction in an attitude in which the image forming apparatus is normally used, a gap L 2   b  is formed between the boss  71   a  and the rotation stopping hole  95 . When the image forming apparatus is shipped in a state in which the cartridge C is attached to the apparatus body A, the force exceeding the weight of the cartridge C and the pressing force E may be applied to the cartridge C during transportation. In this case, the cartridge C can move relative to the apparatus body A within the range of the gaps L 1   a , L 1   b , L 2   a , and L 2   b.    
     Moreover, in the horizontal direction in an attitude in which the image forming apparatus is normally used, a gap L 3   a  is formed between an end surface of the opening  169   f  of the driving-side drum side member  169  and the developing terminal supporting member  92 . In the vertical direction in an attitude in which the image forming apparatus is normally used, a gap L 3   b  is formed between an end surface of the opening  169   f  of the driving-side drum side member  169  and the developing terminal supporting member  92 . Moreover, in the horizontal direction in an attitude in which the image forming apparatus is normally used, a gap L 4   a  is formed between an end surface of the opening  169   g  and the charging terminal supporting member  93 . In the vertical direction in an attitude in which the image forming apparatus is normally used, a gap L 4   b  is formed between an end surface of the opening  169   g  and the charging terminal supporting member  93 . 
     Here, in the second embodiment, the gaps are in the following relation: L 1   a ≅L 2   a ≅L 3   a ≅L 4   a  and L 1   b ≅L 2   b ≅L 3   b ≅L 4   b . That is, in a direction in which the cartridge C can move relative to the apparatus body A, the amount that the developing terminal supporting member  92  can move in the opening  169   f  is approximately the same as the amount that the cartridge C can move relative to the apparatus body A. Moreover, in the direction in which the cartridge C can move relative to the apparatus body A, the amount that the charging terminal supporting member  93  can move in the opening  169   g  is approximately the same as the amount that the cartridge C can move relative to the apparatus body A. 
     When the image forming apparatus is shipped in a state in which the cartridge C is attached to the apparatus body A, the force exceeding the weight of the cartridge C and the pressing force E may be applied to the cartridge C during transportation. In this case, in the second embodiment, the driving-side drum side member  169  receives the force at the four positions of the positioning hole  94 , the rotation stopping hole  95 , the opening  169   f , and the opening  169   g . In this manner, since the force received by the driving-side drum side member  169  is distributed to the four positions, it is possible to reduce the risk that the apparatus body A and the cartridge C are damaged. 
     As described above, the second embodiment provides the same effects as the first embodiment. 
     Moreover, in the second embodiment, a predetermined gap is formed between a terminal supporting member and an opening in a state in which the cartridge C (the process cartridge) is attached to the apparatus body A. Moreover, the predetermined gap is formed so that in the direction in which the cartridge C can move relative to the apparatus body A, the amount that a terminal supporting portion can move relative to the opening is approximately the same as the amount that the cartridge C can move relative to the apparatus body A. Due to this, it is possible to distribute the force that the cartridge C receives from the outside. 
     In the respective embodiments, the process cartridge is attached to the apparatus body of the image forming apparatus whereby an electrical terminal formed on the process cartridge is electrically connected to an electrical terminal formed on the apparatus body. However, the present invention is not necessarily limited to this. For example, a developing cartridge may be attached to the apparatus body of the image forming apparatus whereby an electrical terminal formed on the developing cartridge is electrically connected to an electrical terminal formed on the apparatus body. 
     Moreover, in the respective embodiments, an electrical terminal for applying a voltage to a developing roller and an electrical terminal for applying a voltage to a charging roller are disposed inside an opening formed in a frame. However, the present invention is not necessarily limited to this. For example, an electrical terminal for applying a voltage to the other electrical path such as an electrostatic capacitance-type residual toner amount detection circuit may be disposed inside an opening formed in a frame. 
     While the present invention has been described with reference to exemplary embodiments, it is to be understood that the invention is not limited to the disclosed exemplary embodiments. The scope of the following claims is to be accorded the broadest interpretation so as to encompass all such modifications and equivalent structures and functions. 
     This application claims the benefit of Japanese Patent Application No. 2015-132988, filed on Jul. 1, 2015, which is hereby incorporated by reference herein in its entirety.