JP4485284B2 - Image forming apparatus - Google Patents

Description

  The present invention relates to an image forming apparatus such as a laser printer.

An electrophotographic image forming apparatus includes a scanner unit for high-speed scanning with a laser beam based on image data, and a process cartridge including a charger, a photosensitive drum, a developing roller, a transfer roller, and a cleaner. Is provided.
Such an image forming apparatus is provided with a high-voltage power supply substrate for applying a discharge bias, a developing bias, a transfer bias, and a cleaning bias to a charger, a developing roller, a transfer roller, and a cleaner, respectively. A gear plate is provided for supporting a motor and a gear transmission mechanism for transmitting a driving force for rotationally driving the developing roller and the transfer roller.

An image forming apparatus has been proposed in which an engine drive circuit board including a high-voltage power supply circuit section, a motor, and a drive section are vertically arranged on the opposite side surfaces of the main body (see, for example, Patent Document 1).
JP 2003-195594 A

In recent years, downsizing of image forming apparatuses has been demanded. In order to reduce the size of the image forming apparatus, it is desirable that the input of the driving force and the power supply to the process cartridge be performed from the same side in the apparatus main body. For this purpose, the high-voltage power supply board and the gear plate are attached to the process cartridge. It is necessary to arrange on the same side.
However, if the high-voltage power supply board and the gear plate are arranged on the same side with respect to the process cartridge, there is a risk that the bias applied from the high-voltage power supply board will leak around the gear plate.

  An object of the present invention is to arrange a high-voltage board and a gear plate on the same side wall side to prevent a leak of a bias applied from the high-voltage board around the gear plate while reducing the size of the apparatus. An object of the present invention is to provide an image forming apparatus capable of performing the above.

In order to achieve the above object, according to a first aspect of the present invention, in the image forming apparatus, the first side wall and the second side wall, the first side wall, and the second side wall, which are arranged to face each other with a predetermined interval therebetween. A process member used for an image forming process, a drive source disposed on the first side wall side with respect to the process member, and generating a drive force for the process member; and from the drive source A first gear for transmitting the driving force to the process member, a gear plate made of a sheet metal disposed on the first side wall side to support the first gear with respect to the process member, and the process On the first side wall side with respect to the member, at least a part of the gear plate does not overlap with the gear plate in the facing direction of the first side wall and the second side wall. A high-voltage board that is arranged so as to be opposed to each other and that generates a bias to be applied to the process member, and a power supply that is arranged in a portion of the high-voltage board that does not overlap the gear plate in the opposed direction and outputs the bias And an output terminal.

  According to such a configuration, the high-pressure board is arranged so that at least a part thereof does not overlap with the gear plate in the facing direction of the first side wall and the second side wall, and is not overlapped with the gear plate of the high-pressure board. A power output terminal for outputting a bias applied to the process member is disposed. For this reason, the high voltage substrate and the gear plate can be arranged on the first side wall side to reduce the size of the apparatus, while preventing leakage of bias from the power supply output terminal around the gear plate.

According to a second aspect of the present invention, in the first aspect of the present invention, the power output terminal is disposed at an edge of a portion of the high voltage board that does not overlap the gear plate in the facing direction. It is characterized by.
According to such a configuration, a large distance between the power output terminal and the gear plate can be ensured, and bias leakage from the power output terminal around the gear plate can be further prevented.

The invention described in claim 3 is characterized in that, in the invention described in claim 1 or 2, an insulating sheet is provided that covers a portion of the gear plate that overlaps the high-voltage board in the facing direction.
According to such a configuration, since the insulating sheet is interposed between the overlapping portions of the high-pressure board and the gear plate in the opposing direction of the first side wall and the second side wall, it is possible to insulate them. For this reason, it is possible to reliably prevent bias leakage from the power supply output terminal around the gear plate.

  According to a fourth aspect of the present invention, in the invention according to any one of the first to third aspects, the process member includes a photoconductor and a wire, and charging means for charging the photoconductor. Transfer means for transferring a developer image carried on the photosensitive member to a recording medium, and the power output terminal includes a discharge bias output terminal for outputting a discharge bias to the wire, and A transfer bias output terminal for outputting a transfer bias to the transfer means, and the discharge bias output terminal and the transfer bias output terminal are arranged at a distance at which no leakage occurs between these terminals. It is characterized by that.

According to such a configuration, leakage between the discharge bias output terminal that outputs a relatively high bias and the transfer bias output terminal can be prevented.
According to a fifth aspect of the present invention, in the invention according to any one of the first to third aspects, the process member includes a photoconductor, a wire, and a grid, and charging for charging the photoconductor. Means, developing means for developing an electrostatic latent image formed on the photoconductor, transfer means for transferring a developer image carried on the photoconductor to a recording medium, and cleaning the photoconductor The power output terminal includes a discharge bias output terminal for outputting a discharge bias to the wire, and a transfer bias output terminal for outputting a transfer bias to the transfer means. And a grid bias for the grid, a developing bias for the developing means, or a cleaning bias for the cleaning means. A distance between the discharge bias output terminal and the transfer bias output terminal is a distance between the discharge bias output terminal and the third bias output terminal, or the transfer bias output terminal. And the third bias output terminal are set to be longer than the distance between them.

  According to such a configuration, the distance between the discharge bias output terminal that outputs a relatively high bias and the transfer bias output terminal is a third bias output that outputs a relatively low bias with the discharge bias output terminal or the transfer bias output terminal. It is set longer than the distance between the terminals. Therefore, leakage between the discharge bias output terminal and the transfer bias output terminal can be prevented.

  According to a sixth aspect of the present invention, in the invention according to any one of the first to third aspects, the process member includes a photosensitive member, a charging unit for charging the photosensitive member, and the photosensitive member. A developing unit for developing the formed electrostatic latent image; and a transferring unit for transferring the developer image carried on the photosensitive member to a recording medium. The power output terminal is connected to the charging unit. In contrast, a charging bias output terminal for outputting a charging bias, a transfer bias output terminal for outputting a transfer bias to the transfer unit, and a developing bias output terminal for outputting a developing bias to the developing unit The distance between the charging bias output terminal and the transfer bias output terminal is the distance between the charging bias output terminal and the developing bias output terminal or the transfer bias output terminal. It is characterized in that it is longer than the distance between the bias output terminal and the developing bias output terminal.

  According to such a configuration, the distance between the charging bias output terminal that outputs a relatively high bias and the transfer bias output terminal is a developing bias output terminal that outputs a relatively low bias with the charging bias output terminal or the transfer bias output terminal. It is set longer than the distance between. Therefore, leakage between the charging bias output terminal and the transfer bias output terminal can be prevented.

  According to a seventh aspect of the present invention, in the invention according to any one of the first to sixth aspects, the process member includes a photoconductor, a wire, and a grid, and charging for charging the photoconductor. Means, developing means for developing an electrostatic latent image formed on the photoconductor, transfer means for transferring a developer image carried on the photoconductor to a recording medium, and cleaning the photoconductor A power supply output terminal for outputting a discharge bias to the wire, a transfer bias for the transfer means, a grid bias for the grid, and a developing means. And a bias output terminal for outputting a developing bias or a cleaning bias for the cleaning means. A discharge bias conductor disposed on the sidewall and connected to the discharge bias output terminal; an other bias conductor disposed on the first sidewall and connected to the other bias output terminal; and And a shielding member interposed between the discharge bias conducting wire and the other bias conducting wire to prevent leakage between the discharge bias conducting wire and the other bias conducting wire. It is said.

According to such a configuration, since the shielding member is interposed between the discharge bias lead and the other bias lead, leakage between the discharge bias lead and the other bias lead can be prevented. .
According to an eighth aspect of the present invention, in the invention according to any one of the first to sixth aspects, the process member includes a photosensitive member, a charging unit for charging the photosensitive member, and the photosensitive member. A developing unit for developing the formed electrostatic latent image; and a transferring unit for transferring the developer image carried on the photosensitive member to a recording medium. The power output terminal is connected to the charging unit. And a charging bias output terminal for outputting a charging bias, and another bias output terminal for outputting a transfer bias for the transfer means or a developing bias for the developing means, and disposed on the first side wall. A charging bias conducting wire connected to the charging bias output terminal, and another bias conducting wire disposed on the first side wall and connected to the other bias output terminal, and to the first side wall. A shielding member interposed between the charging bias lead and the other bias lead, and for preventing leakage between the charging bias lead and the other bias lead. It is a feature.

According to such a configuration, since the shielding member is interposed between the charging bias conducting wire and the other bias conducting wire, leakage between the charging bias conducting wire and the other bias conducting wire can be prevented. .
The invention according to claim 9 is the invention according to claim 8, wherein the charging means includes a wire and a grid, and the charging bias output terminal outputs a discharge bias to the wire. The charging bias lead is a discharge bias lead to which the discharge bias output terminal is connected.

According to such a configuration, since the shielding member is interposed between the discharge bias lead and the other bias lead, leakage between the discharge bias lead and the other bias lead can be prevented. .
The invention according to claim 10 is the invention according to claim 7 or 9, wherein the shielding member outputs the discharge bias output when the discharge bias output terminal is connected to the discharge bias conducting wire. It also serves as a guide means for guiding the movement of the terminal.

According to such a configuration, since the shielding member also serves as the guide means, the configuration can be simplified and the number of parts can be reduced while the discharge bias output terminal can be reliably connected to the discharge bias conducting wire. .
The invention according to claim 11 is the invention according to claim 10, wherein a charging transformer for generating the discharge bias is mounted on the high-voltage substrate, and the discharge bias output terminal is It is disposed on the charging transformer, and the shielding member is disposed at a position where the shielding member slides against the charging transformer when the discharge bias output terminal is connected to the discharge bias conducting wire. It is said.

According to such a configuration, the discharge bias output terminal can be connected to the discharge bias conducting wire by sliding the charging transformer against the shielding member. Therefore, workability when connecting the discharge bias output terminal to the discharge bias lead can be improved.
The invention according to claim 12 is the invention according to any one of claims 1 to 11, wherein the process member includes a photoconductor, and the photoconductor is grounded through the gear plate. It is characterized by that.

According to such a configuration, if the gear plate is grounded, the configuration for grounding the photoreceptor can be simplified.
An invention according to claim 13 is the invention according to any one of claims 1 to 12, wherein an opening / closing cover that opens and closes an opening formed between the first side wall and the second side wall; The connection position that advances from the first side wall in the facing direction and can transmit the driving force to the process member, and retracts from the connecting position to the outside in the facing direction to release the transmission of the driving force to the process member. An advancing / retreating member capable of advancing and retreating to and from a release position, and an arm that is disposed between the opening / closing cover and the advancing / retreating member and moves the advancing / retreating member in conjunction with opening / closing of the opening / closing cover, The power output terminal is arranged on the side opposite to the side on which the arm is provided with respect to the advance / retreat member.

According to such a configuration, the power output terminal is disposed on the side opposite to the side on which the arm is provided with respect to the advance / retreat member. Therefore, it is possible to prevent interference between the arm that moves when the advance / retreat member is advanced / retracted and the power output terminal.
According to the invention described in claim 14, in the invention described in any one of claims 1 to 13, a transformer is mounted on the high-voltage board so as to protrude toward the gear plate. It is characterized by that.

  According to such a configuration, since the transformer mounted on the high-voltage board protrudes toward the gear plate, the high-voltage board is arranged outside the first side wall in the opposing direction of the first side wall and the second side wall. Even if it is a structure, it can prevent that a trans | transformer protrudes outside a high voltage | pressure board | substrate. Therefore, the size of the device in the opposing direction of the first side wall and the second side wall can be reduced. As a result, the device can be further miniaturized.

The invention according to claim 15 is the invention according to claim 14, wherein at least a part of the high-voltage board is arranged to face the gear plate in the facing direction, and the transformer is the gear plate. And mounted in a portion that does not overlap in the facing direction.
According to such a configuration, since the transformer is mounted in a portion that does not overlap the gear plate of the high-voltage board in the opposing direction of the first sidewall and the second sidewall, the transformer and the gear plate in the direction orthogonal to the opposing direction. Can be arranged in an overlapping manner. Therefore, the space | interval between a high voltage | pressure board | substrate and a gear plate can be narrowed, and the size of the apparatus in the opposing direction of a 1st side wall and a 2nd side wall can be made by that much. As a result, the apparatus can be further reduced in size.

According to a sixteenth aspect of the present invention, in the invention according to any one of the first to fifteenth aspects, the process member is disposed on the first side wall side and applies the bias to the process member. It is characterized by having a contact point connected to.
According to such a configuration, since the contact point connected to apply a bias to the process member is arranged on the first side wall side, the wiring for electrically connecting the contact point and the power output terminal can be shortened. . Therefore, the wiring structure between the contact and the power output terminal can be simplified.

According to a seventeenth aspect of the invention, in the invention of the sixteenth aspect, the first side wall and the high-pressure board are disposed to face each other with the gear plate interposed therebetween, avoiding the gear plate, A connection member for electrically connecting the contact and the high-voltage board is provided.
According to such a configuration, it is possible to electrically connect the contact disposed on the first side wall side and the high-voltage board via the connection member while avoiding the gear plate. Therefore, it is possible to eliminate the need for penetrating the wiring for connecting the contact and the high-voltage board to the gear plate. As a result, the wiring structure for electrical connection between the contact and the high voltage substrate can be simplified.

The invention described in claim 18 is characterized in that, in the invention described in claim 17, the connecting member is made of a wire.
According to such a configuration, the configuration of the connection member can be simplified.
According to a nineteenth aspect of the present invention, in the invention of the seventeenth or eighteenth aspect, an opening / closing cover that opens and closes an opening formed between the first side wall and the second side wall; A connecting position that advances from the side wall to the inside in the facing direction and can transmit a driving force to the process member, and a release position that retreats from the connecting position to the outside in the facing direction and releases the transmission of the driving force to the process member The first side wall, comprising: an advancing / retracting member capable of advancing and retracting; and an arm disposed between the opening / closing cover and the advancing / retreating member, and for advancing / retreating the advancing / retreating member in conjunction with opening / closing of the opening / closing cover. The arm is disposed between the gear plate and the gear plate.

According to such a configuration, the space between the first side wall and the gear plate can be effectively utilized as a space for arranging the arm.
The invention according to claim 20 is the invention according to any one of claims 1 to 19, wherein the process member is arranged on the second side wall side and generates a voltage lower than that of the high-voltage substrate. A low-pressure substrate, a mounting plate for mounting a recording medium on which an image is recorded by the process member, and electrically connected to the low-pressure substrate, provided to protrude from the second side wall, It is characterized by comprising a ground contact that contacts the mounting plate.

According to such a configuration, the mounting plate can be grounded via the ground contact and the low-voltage board by the earth contact electrically connected to the low-voltage board contacting the mounting board. Therefore, the grounding of the mounting plate can be achieved with a simple configuration.
The invention according to claim 21 is the invention according to any one of claims 1 to 20, wherein a mounting plate for mounting a recording medium on which an image is recorded by the process member; A cassette that accommodates a plate and is detachably mounted between the first side wall and the second side wall; and a lock mechanism that is provided on the second side wall and restricts detachment of the cassette; A second gear provided on the first side wall for moving the mounting plate from a mounting position for mounting the recording medium to a transport position for transporting the recording medium; The second gear is provided so as to rotate in a direction that urges the cassette in the mounting direction, and the cassette is coupled to the first side wall by the cooperation of the lock mechanism and the second gear. Separation from between the second side wall It is characterized by being regulated.

  According to such a configuration, the detachment of the cassette from between the first side wall and the second side wall is regulated by the cooperation of the lock mechanism and the second gear. Therefore, the lock mechanism can be provided only on the second side wall. As a result, it is possible to simplify the configuration for regulating the detachment of the cassette.

According to the first aspect of the present invention, the high-voltage board and the gear plate are arranged on the first side wall side, and the apparatus can be reduced in size, but the bias from the power supply output terminal around the gear plate can be reduced. Leakage can be prevented.
According to the second aspect of the present invention, it is possible to further prevent bias leakage from the power supply output terminal around the gear plate.

According to the third aspect of the present invention, it is possible to reliably prevent the leakage of the bias from the power supply output terminal around the gear plate.
According to the fourth aspect of the present invention, it is possible to prevent leakage between the discharge bias output terminal that outputs a relatively high bias and the transfer bias output terminal.
According to the fifth aspect of the present invention, leakage between the discharge bias output terminal and the transfer bias output terminal can be prevented.

According to the sixth aspect of the present invention, it is possible to prevent leakage between the charging bias output terminal and the transfer bias output terminal.
According to the seventh aspect of the present invention, it is possible to prevent leakage between the discharge bias lead wire and the other bias lead wire.
According to the eighth aspect of the present invention, it is possible to prevent leakage between the charging bias conductor and the other bias conductor.

According to the ninth aspect of the present invention, it is possible to prevent leakage between the discharge bias conducting wire and the other bias conducting wire.
According to the tenth aspect of the present invention, the discharge bias output terminal can be reliably connected to the discharge bias conducting wire, and the configuration can be simplified and the number of parts can be reduced.

According to the eleventh aspect of the present invention, it is possible to improve workability when the discharge bias output terminal is connected to the discharge bias conducting wire.
According to the twelfth aspect of the present invention, the configuration for grounding the photosensitive member can be simplified.
According to the thirteenth aspect of the present invention, it is possible to prevent interference between the arm that moves when the advance / retreat member is advanced and retracted and the power output terminal.

According to the invention of the fourteenth aspect, the device can be further reduced in size.
According to the invention of the fifteenth aspect, the device can be further reduced in size.
According to the sixteenth aspect, the wiring structure between the contact and the power output terminal can be simplified.
According to the invention described in claim 17, it is possible to simplify the wiring structure for electrical connection between the contact provided on the first side wall side and the high voltage substrate.

According to the invention described in claim 18, the configuration of the connecting member can be simplified.
According to the nineteenth aspect of the present invention, the space between the first side wall and the gear plate can be effectively utilized as a space for arranging the arm.
According to invention of Claim 20, earthing | grounding of a mounting board can be achieved by simple structure.

  According to the twenty-first aspect of the present invention, it is possible to simplify the configuration for restricting the detachment of the cassette.

FIG. 1 and FIG. 2 are cross-sectional side views showing a main part of an embodiment of a laser printer as an image forming apparatus of the present invention. This laser printer 1 includes a feeder unit 4 for feeding a sheet 3 as a recording medium and an image forming unit 5 for forming an image on the fed sheet 3 in a main body casing 2. Yes.
In the main casing 2, an attachment / detachment opening 6 for attaching / detaching a process cartridge 18 described later is formed on one side wall, and a front cover 7 as an opening / closing cover for opening / closing the attachment / detachment opening 6 is provided. Is provided.

  The front cover 7 is rotatably supported by a cover shaft (not shown) inserted through the lower end portion thereof. As a result, when the front cover 7 is closed around the cover shaft, the detachable opening 6 is closed by the front cover 7 as shown in FIG. 1, and when the front cover 7 is opened with the cover shaft as a fulcrum (when tilted). As shown in FIG. 2, the attachment / detachment opening 6 is opened, and the process cartridge 18 can be attached to / detached from the main casing 2 through the attachment / detachment opening 6.

Hereinafter, in the laser printer 1 and the process cartridge 18 (including a developing cartridge 26 described later), the side on which the front cover 7 is provided is referred to as “front side”, and the opposite side is referred to as “rear side”.
The feeder unit 4 includes a paper feed tray 8 that is detachably attached to the bottom of the main casing 2, a paper feed roller 9 and a separation pad 10 that are provided above the front end of the paper feed tray 8, and a paper feed roller 9, a pickup roller 11 provided on the rear side of the sheet feeding roller 9, a pinch roller 12 disposed oppositely on the lower front side of the sheet feeding roller 9, and a registration roller 13 provided on the upper rear side of the sheet feeding roller 9.

As shown in FIGS. 1 to 4, the sheet feed tray 8 surrounds a rectangular plate-like bottom plate 59 and a space on the bottom plate 59, and a front wall that stands vertically from the peripheral edge of the bottom plate 59. 60, a rear wall 61, a left side wall 62, and a right side wall 63 are integrally provided.
The front wall 60 is coupled to the front edge of the bottom plate 59. As shown in FIGS. 3 and 4, the front wall 60 is formed with a grip portion 64 having a substantially triangular shape in a side view. By grasping the grip portion 64 and sliding the paper feed tray 8 back and forth with respect to the main body casing 2, the paper feed tray 8 is detached from the main body casing 2 or the paper feed tray 8 is attached to the main body casing 2. You can do it.

The rear wall 61 is coupled to the rear edge of the bottom plate 59.
As shown in FIG. 3, the left side wall 62 is coupled to the left end edge of the bottom plate 59, and is formed with a gear arrangement portion 65 having a substantially rectangular shape in side view and a lower height than the gear arrangement portion 65. A left wall rear portion 66 extending rearward from the rear end portion of the placement portion 65 is provided. The gear placement unit 65 includes an input gear 67 that meshes with a lever driving force transmission gear 177 (described later) provided in the main body casing 2 when the paper feed tray 8 is mounted on the main body casing 2. A lever driving gear 68 that meshes with the gear 67 and is rotated by the driving force transmitted from the input gear 67 is disposed.

  As shown in FIG. 4, the right side wall 63 is coupled to the right end edge of the bottom plate 59, and is formed with a right wall front part 69 that is substantially rectangular in side view and a height lower than the right wall front part 69. And a right wall rear portion 70 extending rearward from the rear end portion of the right wall front portion 69. At the front end of the rear portion 70 of the right wall, when the paper feed tray 8 is attached to the main casing 2, a lock piece as a locking mechanism having a substantially triangular shape in plan view to which a tray lock piece 179 described later is locked. A locking portion 71 is provided. In addition, a ground connection hole 72 into which a pressing plate ground contact 183 described later is fitted when the paper feed tray 8 is mounted on the main body casing 2 is formed in the middle portion in the front-rear direction of the rear portion 70 of the right wall.

Further, as shown in FIGS. 1 and 2, the paper feed tray 8 includes a paper pressing plate 14 as a metal mounting plate on which the paper 3 can be stacked on the bottom plate 59, and the paper pressing plate. A lever 15 for lifting the front end of the paper pressing plate 14 upward is provided on the front side of the plate 14.
The paper pressing plate 14 is swingably supported at the rear end portion, so that the front end portion is movable in the vertical direction.

  The lever 15 is formed in a substantially L-shaped cross section so as to go from the front side to the lower side of the paper pressing plate 14, and its upper end is orthogonal to the front-rear direction (hereinafter simply referred to as “width direction”). The rear end portion is attached to the extending lever shaft 16 and is in contact with the front end portion of the lower surface of the sheet pressing plate 14. The lever shaft 16 penetrates the left side wall 62 and protrudes outward in the width direction of the left side wall 62, and the lever drive gear 68 cannot be rotated relative to the left end protruding from the left side wall 62 of the lever shaft 16. Is attached. The lever shaft 16 is rotatably supported on a rib (not shown) on the bottom plate 59.

  When the paper feed tray 8 is attached to the main casing 2, a later-described lever driving force transmission gear 177 provided in the main casing 2 and the input gear 67 are engaged with each other, and the lever driving force transmission gear 177 to the input gear 67 in this state. When the driving force is input to the lever, the lever 15 rotates about the lever shaft 16 as the input gear 67 rotates, and the rear end portion of the lever 15 lifts the front end portion of the paper pressing plate 14.

When the front end portion of the sheet pressing plate 14 is lifted, the uppermost sheet 3 on the sheet pressing plate 14 is pressed by the pickup roller 11, and the sheet feeding roller 9, the separation pad 10, and the like are rotated by the rotation of the pickup roller 11. The conveyance is started in between.
On the other hand, when the paper feed tray 8 is detached from the main casing 2, the meshing between the input gear 67 and the lever driving force transmission gear 177 is released, and the front end of the paper pressing plate 14 moves downward due to its own weight. Then, the state is along the bottom plate 59 of the paper feed tray 8. In this state, the sheets 3 can be stacked on the sheet pressing plate 14.

  An arcuate guide member 85 having a substantially arc-shaped cross section is disposed above the front side of the paper feed roller 9 so as to cover between the frontmost position and the uppermost position of the outer peripheral surface of the paper feed roller 9. More specifically, the arcuate guide member 85 is formed in a curved plate shape having a substantially arc-shaped cross section that curves along the outer peripheral surface of the paper feed roller 9, and is the foremost position on the outer peripheral surface of the paper feed roller 9. And the uppermost position are provided at almost equal intervals.

  The paper 3 sent out by the pickup roller 11 is reliably rolled one by one when sandwiched between the paper supply roller 9 and the separation pad 10, and then the paper supply roller 9 is rotated by the rotation of the paper supply roller 9. 9 and the pinch roller 12. Then, the sheet 3 that has passed between the sheet feed roller 9 and the pinch roller 12 enters between the sheet feed roller 9 and the arcuate guide member 85, and the sheet feed roller 9 and the arcuate guide member 85 Is conveyed along the outer peripheral surface of the paper feed roller 9.

  A resin guide plate 86 extending in the front-rear direction is provided behind the paper feed roller 9. The guide plate 86 is connected to an upstream portion 87 inclined downward from the vicinity of the upper portion of the paper feed roller 9 toward the rear, and a concave shape that covers the transfer roller 30 described below from below. And a downstream portion 89 having an upper surface that is connected to the rear side of the intermediate portion 88 and is inclined upward toward the rear.

The registration roller 13 is composed of a pair of upper and lower rollers facing each other. At the front end portion of the upstream portion 87 of the guide plate 86, the lower roller is disposed in a state of protruding from the upper surface of the guide plate 86, The upper roller is in pressure contact with the lower roller.
The sheet 3 conveyed between the sheet feeding roller 9 and the separation pad 10 is separated from the outer circumferential surface of the sheet feeding roller 9 in the vicinity of the uppermost portion of the outer circumferential surface of the sheet feeding roller 9, and the upstream portion of the guide plate 86 87 is sent over. Then, after the sheet 3 sent onto the upstream portion 87 of the guide plate 86 is registered by the registration roller 13, the image forming unit 5 forms an image on the upstream portion 87 of the guide plate 86 by the rotation of the registration roller 13. The sheet is conveyed toward a position (a nip position between a photosensitive drum 28 and a transfer roller 30, which will be described later, and a position where a toner image on the photosensitive drum 28 is transferred to the paper 3).

The image forming unit 5 includes a scanner unit 17, a process cartridge 18, a fixing unit 19, and the like.
The scanner unit 17 is provided in the upper part of the main casing 2 and includes a laser light source (not shown), a polygon mirror 20 that is rotationally driven, an fθ lens 21, a reflecting mirror 22, a lens 23, a reflecting mirror 24, and the like. The laser beam based on the image data emitted from the laser light source is deflected by the polygon mirror 20 as shown by a chain line, passes through the fθ lens 21, then the optical path is turned back by the reflecting mirror 22, and further passes through the lens 23. After that, the optical path is further bent downward by the reflecting mirror 24, so that the surface of a photosensitive drum 28 (to be described later) of the process cartridge 18 is irradiated at high speed.

The process cartridge 18 is detachably attached to the main body casing 2 below the scanner unit 17. The process cartridge 18 includes a drum cartridge 25 and a developing cartridge 26 that is detachably attached to the drum cartridge 25.
As shown in FIGS. 5 and 6, the drum cartridge 25 includes a cartridge frame 91, a photosensitive drum 28 as a photosensitive member as a process member and a scorotron as a charging means as a process member provided in the cartridge frame 91. A mold charger 29, a transfer roller 30 as a transfer means as a process member, and a cleaning brush 31 as a cleaning means as a process member are provided.

The cartridge frame 91 is integrally provided with a left side wall 96, a right side wall 97, a bottom wall 98, a front wall 99 and a rear upper wall 100.
The left side wall 96 and the right side wall 97 are opposed to each other with an interval in the width direction, and the rear side wall part 105 having a substantially bow shape in side view, the front side wall part 106 having a substantially rectangular shape in side view, and a substantially rectangular shape in side view. The extended side wall 107 having a shape is formed successively from the rear side toward the front side.

The front side wall portion 106 is provided continuously to a roller shaft guide portion 115 for guiding a shaft end portion of a developing roller shaft 48, which will be described later, and a rear end of the roller shaft guide portion 115 when the developing cartridge 26 is attached and detached. And a roller bearing insertion portion 116 that receives the shaft end portion of the developing roller shaft 48 guided by the roller shaft guide portion 115.
The roller shaft guide part 115 is formed as an upper end edge of the front side wall part 106, and extends from the middle in the front-rear direction of the front side wall part 106 diagonally downward from the front to the rear, and then extends in a substantially horizontal flat shape. It is formed as follows.

The roller bearing insertion portion 116 is continuous with the rear side of the roller shaft guide portion 115, and protrudes upward from the rear end portion of the roller shaft guide portion 115. The roller bearing insertion portion 116 is substantially rectangular in a side view from the front end edge of the protrusion wall 117. It is formed by cutting out into a shape, and its lower end edge is continuous with the rear end edge of the roller shaft guide portion 115.
The extended side wall 107 is flush with the front side wall 106 in the width direction and is formed continuously.

The bottom wall 98 has a substantially flat plate shape and is provided so as to connect lower end edges of the left side wall 96 and the right side wall 97 in the front-rear direction.
The front wall 99 is formed to bend in a perpendicular direction upward from the front edge of the bottom wall 98. The front wall 99 has a substantially rectangular flat plate shape, and both end portions in the width direction are formed continuously with the left side wall 96 and the right side wall 97 so as to be bent in a right angle direction.

  The rear upper wall 100 has a plate shape that is slightly inclined downward from the front to the rear, and is provided so as to connect the upper end edges of the rear side wall portions 105 of the left side wall 96 and the right side wall 97 in the front-rear direction. It has been. The rear upper wall 100 has a rear end edge connected to the rear end edge of the bottom wall 98 in the width direction. Further, a laser incident window 121 having a substantially rectangular shape in plan view extending in the width direction is opened at the front portion of the rear upper wall 100. Further, the rear upper wall 100 has a charging support portion 122 for supporting the scorotron charger 29 obliquely upward at the rear portion thereof, and a brush support portion 123 for supporting the cleaning brush 31 on the inner side of the rear portion thereof. Are integrally formed.

  In this cartridge frame 91, the drum housing portion is constituted by the rear side wall portions 105 of the left side wall 96 and the right side wall 97, the rear upper wall 100, and the rear portion of the bottom wall 98 facing the upper wall 100 in the vertical direction. 102 is formed as a closed space where the front is opened. Further, the upper portion of the developing cartridge housing portion 103 is opened by the front side wall portions 106 of the left side wall 96 and the right side wall 97 and the middle portion of the bottom wall 98 that is continuous with the front side wall portions 106 in the width direction. The front portion is formed as a space communicating with the extension 104 described below, and the rear portion is formed as a space communicating with the drum housing portion 102. Furthermore, the extended portion 104 is opened upward by the extended side wall portion 107 of the left side wall 96 and the right side wall 97, the front portion of the bottom wall 98 continuous in the width direction with each extended side wall portion 107, and the front wall 99. Thus, the rear side is formed as a space communicating with the developing cartridge housing portion 103.

  As shown in FIG. 6, the photosensitive drum 28 is provided in the drum housing portion 102. The photosensitive drum 28 extends along the longitudinal direction of the drum body 32 at the axial center of the drum body 32 and a cylindrical drum body 32 formed by a positively chargeable photosensitive layer whose outermost layer is made of polycarbonate or the like. And a metal drum shaft 33. The drum shaft 33 is non-rotatably supported on both side plates 27 of the drum cartridge 25, and the drum main body 32 is rotatably supported on the drum shaft 33, so that the photosensitive drum 28 is disposed between the both side plates 27. The shaft 33 is provided to be rotatable.

As shown in FIG. 7, the left end portion of the drum shaft 33 protrudes from the left wall 96 of the drum cartridge 25, and the end surface of the left end portion is in contact with a drum earth electrode 73 with which a drum earth contact 166 described later contacts. Has been.
As shown in FIG. 6, the scorotron charger 29 is disposed in the drum housing portion 102 and is supported by the charging support portion 122 obliquely above the rear side of the photosensitive drum 28 so as not to contact the photosensitive drum 28. Are opposed to each other with an interval. The scorotron charger 29 includes a wire 74 and a grid 75.

  The wire 74 is stretched between the left side wall 96 and the right side wall 97 in the charging support portion 122. As shown in FIG. 7, a wire electrode 76 made of sheet metal is attached to the left end portion of the wire 74, and the wire electrode 76 is connected to the upper front end portion (drum ground) of the rear side wall portion 105 of the left side wall 96. In the upper part of the electrode 73), it is fixed so as to be exposed outward in the width direction from between the slits formed in the vertical direction.

  As shown in FIG. 6, the grid 75 is disposed so as to surround the lower side of the wire 74 along the width direction, and is laid between the left side wall 96 and the right side wall 97. As shown in FIG. 7, a grid electrode 77 made of sheet metal is connected to the grid 75, and the grid electrode 77 is connected to the rear end portion of the rear side wall portion 105 of the left side wall 96 (the drum earth electrode 73 of the drum ground electrode 73. In the rear diagonally upper direction), it is fixed so as to be exposed outward in the width direction from between slits formed in a direction inclined obliquely upward from the front lower side.

  The transfer roller 30 is disposed in the drum housing portion 102 and is rotatably supported between the left side wall 96 and the right side wall 97. The transfer roller 30 is in contact with the photosensitive drum 28 from the lower side in the vertical direction. A nip is formed between the nip 28 and the nip 28. The transfer roller 30 is configured by covering a metal transfer roller shaft 34 with a roller 35 made of a conductive rubber material. As shown in FIG. 7, a substantially rectangular transfer electrode hole 78 is formed in the lower end portion of the rear side wall portion 105 of the left side wall 96 (below the drum ground electrode 73). The transfer electrode 79 is embedded so as to be exposed outward in the width direction. The left end portion of the transfer roller shaft 34 is in contact with the transfer electrode 79.

  As shown in FIG. 6, the cleaning brush 31 is disposed in the drum housing portion 102, and is supported by the brush support portion 123 on the rear side of the photosensitive drum 28. The cleaning brush 31 has a large number of brush hairs planted on a substantially rectangular elongated support plate extending in the width direction. The cleaning brush 31 is opposed to the photosensitive drum 28 in the front-rear direction so that the brush hair contacts the surface of the photosensitive drum 28 along the width direction while being supported by the brush support portion 123. Further, a cleaning electrode 80 made of sheet metal is attached to the left end portion of the support plate of the cleaning brush 31, and the cleaning electrode 80 is formed on the rear side wall portion 105 of the left side wall 96 as shown in FIG. At the rear end portion (behind the drum ground electrode 73), it is fixed so as to be exposed outward in the width direction from between the slits formed in the vertical direction.

The developer cartridge 26 is detachably attached to the developer cartridge housing portion 103. As shown in FIGS. 1 and 2, the developer cartridge 26 is formed in a box-like housing 36 having an open rear side, and is provided in the housing 36. Provided with a supply roller 37, a developing roller 38 as a developing means as a process member, and a layer thickness regulating blade 39.
A partition plate 40 is provided in the housing 36 so as to extend in the width direction from the middle of the upper surface in the front-rear direction. The inner space in front of the partition plate 40 is connected to the toner storage chamber 41. The inner space behind the partition plate 40 is a developing chamber 42.

  In the toner storage chamber 41, positively charged nonmagnetic one-component toner is stored as a developer. Examples of the toner include polymerizable monomers such as styrene monomers such as styrene, and acrylic monomers such as acrylic acid, alkyl (C1 to C4) acrylate, and alkyl (C1 to C4) methacrylate. Polymerized toners obtained by copolymerization by a known polymerization method such as suspension polymerization are used. Such a polymerized toner has a spherical shape, has extremely good fluidity, and can achieve high-quality image formation.

Such a toner is blended with a colorant such as carbon black, wax, and the like, and an external additive such as silica is added to improve fluidity. The particle diameter is about 6 to 10 μm.
In addition, an agitator 43 for agitating the toner in the toner storage chamber 41 is provided in the toner storage chamber 41. The agitator 43 is supported by an agitator rotating shaft 44 extending in the width direction at the center of the toner storage chamber 41.

The supply roller 37 is disposed below the front side in the developing chamber 42, and is rotatably supported between both side plates facing the width direction of the housing 36. The supply roller 37 includes a metal supply roller shaft 46 extending in the width direction, and a sponge roller 47 made of a conductive foam material covering the supply roller shaft 46.
The developing roller 38 is disposed below the rear side in the developing chamber 42, is in pressure contact with the supply roller 37, and is provided so that the rear portion is partially exposed rearward from the housing 36. The developing roller 38 is covered with a metal developing roller shaft 48 and a rubber roller 49 made of a conductive rubber material that covers the developing roller shaft 48. More specifically, the rubber roller 49 is made of conductive urethane rubber or silicone rubber containing carbon fine particles, and the surface thereof is covered with fluorine-containing urethane rubber or silicone rubber. Note that both side shaft end portions of the developing roller shaft 48 are provided so as to protrude outward in the width direction from between both side plates of the housing 36, and the end surface of the left shaft end portion thereof is as shown in FIG. A developing roller electrode 81 is in contact with a developing roller contact 163 described later.

  The layer thickness regulating blade 39 is made of a metal leaf spring material, and includes a pressing rubber member 50 having a semicircular cross section made of insulating silicone rubber at the tip. The layer thickness regulating blade 39 is supported by the housing 36 above the developing roller 38, and the lower end thereof is opposed to the rubber roller 49 of the developing roller 38 from the front side, and the pressing rubber member 50 has the layer thickness. The elastic force of the regulating blade 39 is pressed against the surface of the rubber roller 49.

  Further, as shown in FIG. 7, an input gear 82 for inputting a mechanical driving force to the agitator 43, the supply roller 37 and the developing roller 38 is disposed on the left side plate of the housing 36. The input gear 82 is formed with a connection hole 83 at the center thereof, to which a coupling member 186 described later is connected so as not to be relatively rotatable. The input gear 82 is connected to the agitator rotating shaft 44, the supply roller shaft 46, and the developing roller shaft 48 through a gear transmission mechanism (not shown) so that driving force can be transmitted. When a driving force is input from the coupling member 186 to the input gear 82, the agitator 43, the supply roller 37, and the developing roller 38 are rotated by the driving force.

  When a driving force is input from the coupling member 186 to the input gear 82 and the agitator 43 is rotated with the agitator rotating shaft 44 as a fulcrum, the toner in the toner storage chamber 41 is agitated, and below the partition plate 40. The toner is discharged from the toner discharge port 45 toward the developing chamber 42. The toner discharged into the developing chamber 42 is supplied onto the rubber roller 49 of the developing roller 38 by the rotation of the supplying roller 37, and at this time, between the sponge roller 47 of the supplying roller 37 and the rubber roller 49 of the developing roller 38. Is positively triboelectrically charged. The toner supplied onto the rubber roller 49 enters between the pressing rubber member 50 of the layer thickness regulating blade 39 and the rubber roller 49 with the rotation of the developing roller 38 to become a thin layer having a constant thickness. 49 is carried.

On the other hand, the surface of the photosensitive drum 28 is uniformly positively charged by the scorotron charger 29 and then exposed by high-speed scanning of the laser beam from the scanner unit 17 to form an electrostatic latent image based on the image data. .
Next, when the developing roller 38 rotates, the positively charged toner carried on the rubber roller 49 of the developing roller 38 comes into contact with the photosensitive drum 28 and is formed on the surface of the photosensitive drum 28. An electrostatic latent image, that is, a surface of the photosensitive drum 28 that is uniformly positively charged, is supplied to an exposed portion that is exposed to a laser beam and the potential is lowered, and is visualized by being selectively carried. Thus, a toner image is formed by reversal development.

Thereafter, the photosensitive drum 28 and the transfer roller 30 are rotationally driven so as to sandwich and convey the sheet 3 therebetween, and the sheet 3 is conveyed between the photosensitive drum 28 and the transfer roller 30. A toner image carried on the surface of the photosensitive drum 28 is transferred onto the paper 3.
Note that the paper dust adhering to the surface of the photosensitive drum 28 by contact with the paper 3 after the transfer, when the surface of the photosensitive drum 28 faces the brush of the cleaning brush 31 as the photosensitive drum 28 rotates, Removed by the brush.

The fixing unit 19 is provided on the rear side of the process cartridge 18. The fixing frame 51 extends in the width direction. The fixing roller 19 is rotatably supported by the fixing frame 51. It has.
The heating roller 52 includes a metal base tube 193 and a halogen lamp 194 for heating in the metal base tube 193, and is rotationally driven by input of power from a motor (not shown).

The pressing roller 53 is disposed opposite to the heating roller 52 so as to press the heating roller 52. The pressing roller 53 is configured by covering a metal roller shaft 54 with a roller 55 made of a rubber material, and is driven according to the rotational driving of the heating roller 52.
In the fixing unit 19, the toner transferred onto the paper 3 is thermally fixed while the paper 3 passes between the heating roller 52 and the pressing roller 53. The sheet 3 on which the toner is fixed is conveyed to a sheet discharge path 56 that extends in the vertical direction toward the upper surface of the main casing 2. The sheet 3 conveyed to the sheet discharge path 56 is discharged onto a sheet discharge tray 58 formed on the upper surface of the main casing 2 by a sheet discharge roller 57 provided at the upper end of the sheet 3.

  FIG. 8 is a plan view showing the internal configuration of the laser printer 1. The main casing 2 is provided with a left frame 131 as a resin-made first side wall and a right frame 132 as a second side wall, which are opposed to each other in the width direction. A guide plate 86 is installed between the left frame 131 and the right frame 132, and the process cartridge 18 is mounted above the guide plate 86.

  As shown in FIG. 9, the left frame 131 has a substantially rectangular shape extending in the front-rear direction in a side view. A plurality of input gears such as a paper feed roller gear 133 to which driving force is input from a transmission gear 138 described below is supported on the outer surface of the left frame 131. A gear plate 134, a high voltage board 135, and a main board 136 are disposed on the outer surface of the left frame 131.

  The gear plate 134 is made of sheet metal and is disposed so as to extend rearward from the front edge of the left frame 131 along the lower edge of the outer surface of the left frame 131. On the surface of the gear plate 134 facing the left frame 131, a motor 137 as a drive source and a driving force from the motor 137 are applied to the photosensitive drum 28, the paper feed tray 8 (lever 15), the paper feed roller 9, and the like. A plurality of transmission gears 138 serving as first gears for transmission to the vehicle are supported.

  The high voltage substrate 135 boosts the voltage of a single phase 100V supplied from the outside of the laser printer 1 and applies high voltage to the scorotron charger 29, the transfer roller 30, the cleaning brush 31 and the developing roller 38, respectively. This is a power supply substrate that generates a bias. The high-voltage board 135 is formed in a substantially rectangular shape when viewed from the side, and in the width direction (opposite direction of the left frame 131 and the right frame 132), the lower end thereof overlaps the upper end of the gear plate 134. The plate 134 is disposed so as to face the width direction outside.

  As shown in FIG. 10, on the surface of the high-voltage board 135 facing the left frame 131, a charging transformer 139 as a transformer for generating a discharge bias for the wire 74 of the scorotron charger 29, and the transfer roller 30 A transfer transformer 140 as a transformer for generating a transfer bias, a development transformer 141 as a transformer for generating a development bias for the developing roller 38, and a discharge bias that is a power supply output terminal for outputting a discharge bias Output terminal 142, transfer bias output terminal 143 as another bias output terminal that is a power supply output terminal for outputting a transfer bias, and third bias output terminal or other bias as a power supply output terminal for outputting a developing bias A development bias output terminal 144 as an output terminal; In order to output a cleaning bias for the cleaning brush 31 and a grid bias output terminal 145 as a third bias output terminal or other bias output terminal which is a power supply output terminal for outputting a grid bias to the grid 75 of the corotron charger 29. A cleaning bias output terminal 146 as a third bias output terminal or other bias output terminal which is a power supply output terminal of the power supply, and transistors 147 and 148 for switching the bias output from these bias output terminals 142 to 146 and the stop thereof. 149, a heat sink 150 for preventing thermal destruction of the transistor 147, ground connection terminals 151, 152 for ground connection, connectors 153, 154, 155 for electrical connection to the outside, not shown cash register An optical sensor 195 for detecting the position of the detectors constituting the (sensor for detecting the arrival of the sheet 3 in order to control the emission timing of the laser beam from the scanner unit 17) bets after sensor is mounted.

  The charging transformer 139, the transfer transformer 140, the developing transformer 141, and the transistors 148 and 149 are arranged in a region that does not overlap the gear plate 134 in the width direction on the surface of the high-voltage board 135 facing the left frame 131. The ground connection terminals 151, 152, the connectors 153, 154, 155 and the sensor 195 are arranged in a region overlapping the gear plate 134 in the width direction on the surface of the high-voltage board 135 facing the left frame 131. That is, among the components mounted on the surface of the high-voltage board 135 facing the left frame 131, the relatively tall component is disposed in a region that does not overlap the gear plate 134 in the width direction on the facing surface, and is relatively The parts having a low height are arranged in a region overlapping the gear plate 134 in the width direction on the facing surface.

Further, the discharge bias output terminal 142, the transfer bias output terminal 143, the development bias output terminal 144, the grid bias output terminal 145, and the cleaning bias output terminal 146 are connected to the gear plate 134 on the surface facing the left frame 131 of the high voltage substrate 135. It is arranged in an area that does not overlap in the width direction.
More specifically, on the surface of the high-voltage board 135 facing the left frame 131, the charging transformer 139 is disposed at the upper end portion that does not overlap the gear plate 134 in the width direction, and at the middle portion in the front-rear direction. A developing bias output terminal 144, a grid bias output terminal 145, and a cleaning bias output terminal 146 are arranged in this order from the front side behind the charging transformer 139. The discharge bias output terminal 142 is disposed on the rear portion of the charging transformer 139. Further, the transfer transformer 140 is disposed at a front upper end portion that does not overlap the gear plate 134 in the width direction, and the development transformer 141 is a front lower end portion that does not overlap the gear plate 134 in the width direction (below the transfer transformer 140). Is arranged. A transfer bias output terminal 143 is disposed in front of the developing transformer 141, and transistors 148 and 149 are disposed vertically opposite to each other. Further, a heat radiating plate 150 is disposed at the lower end on the rear side overlapping the gear plate 134 in the width direction, and a transistor 147 is disposed on the heat radiating plate 150. Furthermore, the ground connection terminal 151 and the connectors 154 and 155 are juxtaposed along the lower edge of the high-voltage board 135 below the heat sink 150, and the ground connection terminal 152 is arranged at the lower rear corner of the high-voltage board 135. ing. The connector 153 is disposed above the ground connection terminal 152.

  With this arrangement, among the components mounted on the surface facing the left frame 131 of the high-voltage board 135, the charging transformer 139, which is a relatively tall component, and the like are arranged on the gear plate 134 on the facing surface. As shown in FIG. 11, these relatively tall parts are arranged so as to overlap the gear plate 134 in the vertical direction or the front-rear direction.

  Further, the distance between the discharge bias output terminal 142 and the transfer bias output terminal 143 is based on the distance between each of the discharge bias output terminal 142 and the development bias output terminal 144, the grid bias output terminal 145, and the cleaning bias output terminal 146. And a distance at which no leakage occurs between the discharge bias output terminal 142 and the transfer bias output terminal 143 is ensured.

  Also, as shown in FIG. 12, the outer surface of the left frame 131 is an intermediate portion in the front-rear direction at the upper edge, and includes a discharge bias output terminal 142, a development bias output terminal 144, a grid bias output terminal 145, and a cleaning bias. Spring-like connecting members 156, 158, 159, 160 formed by winding a wire are provided in a state of projecting outward in the width direction at positions where the output terminals 146 face each other in the width direction. Further, in the vicinity of the front upper end portion of the outer surface of the left frame 131, a spring-like connection member 157 formed by winding a wire at a position facing the transfer bias output terminal 143 in the width direction faces outward in the width direction. It is provided in a protruding state.

Further, a rib 167 as a shielding member for preventing leakage between the connecting member 156 facing the discharge bias output terminal 142 and the connecting member 158 facing the developing bias output terminal 144 is provided. It is formed to protrude from the outer surface of the left frame 131.
The rib 167 is disposed at a position where it slides on the rear end surface of the charging transformer 139 on which the discharge bias output terminal 142 is disposed. Further, in the rib 167, an inclined surface 167C that is inclined forward toward the outer side in the width direction is formed between the front end surface 167A and the surface 167B facing the high voltage substrate 135. When the high-voltage board 135 is attached to the outer surface of the left frame 131, the charging transformer 139 is guided to the front side of the rib 167 by the inclined surface 167C of the rib 167, and the rear end surface of the charging transformer 139 is set to the rib 167. If the high voltage substrate 135 is brought closer to the outer surface of the left frame 131 while being rubbed against the front end surface 167A, the discharge bias output terminal 142 is reliably brought into contact with the connection member 156. That is, the rib 167 also serves as a guide unit that guides the discharge bias output terminal 142 so as to contact the connection member 156.

  By attaching the high voltage substrate 135 to the outer surface of the left frame 131 while sliding the charging transformer 139 against the front end surface of the rib 167, a discharge bias output terminal 142, a transfer bias output terminal 143, a developing bias output terminal 144, a grid The bias output terminal 145 and the cleaning bias output terminal 146 are elastically brought into contact with the connection members 156, 158, 159, and 160, respectively, in the width direction.

  Further, the high-voltage board 135 is arranged so as to overlap the gear plate 134, and screws (not shown) are screwed into the screw holes 198 and 199 formed in the gear plate 134 via the ground connection terminals 151 and 152, thereby Is fixed to the gear plate 134 and electrically connected to the gear plate 134 and grounded via the gear plate 134.

  On the other hand, as shown in FIG. 14, on the inner side surface of the left frame 131, when the process cartridge 18 is attached to the main casing 2, the wire electrode 76 and the transfer electrode 79 disposed on the left side surface of the process cartridge 18. The wire contact 161, the transfer contact 162, the development roller contact 163, and the grid contact 164 are formed at positions facing the developing roller electrode 81, the grid electrode 77, and the cleaning electrode 80, respectively. And a cleaning contact 165 is provided.

  The wire contact 161 is connected to a connection member 156 facing the discharge bias output terminal 142 via a wiring 168 (see FIG. 12) as a discharge bias conducting wire. As a result, in a state where the process cartridge 18 is mounted on the main casing 2, the discharge bias output terminal 142 of the high voltage substrate 135 and the wire electrode 76 of the process cartridge 18 are connected via the connection member 156, the wiring 168 and the wire contact 161. The discharge bias that is electrically connected around the gear plate 134 and is output from the discharge bias output terminal 142 is applied to the wire 74 of the scorotron charger 29.

  The transfer contact 162 is connected to a connection member 157 facing the transfer bias output terminal 143 via a wiring 169 (see FIG. 12) as another conducting wire for bias. As a result, when the process cartridge 18 is mounted on the main casing 2, the transfer bias output terminal 143 of the high-voltage substrate 135 and the transfer electrode 79 of the process cartridge 18 are connected via the connection member 157, the wiring 169 and the transfer contact 162. The transfer bias that is electrically connected around the gear plate 134 and is output from the transfer bias output terminal 143 is applied to the transfer roller 30.

  The developing roller contact 163 is connected to a connecting member 158 facing the developing bias output terminal 144 via a wiring 170 (see FIG. 12) as another bias conducting wire. As a result, when the process cartridge 18 is mounted on the main casing 2, the developing bias output terminal 144 of the high-voltage substrate 135 and the developing roller electrode 81 of the process cartridge 18 connect the connecting member 158, the wiring 170, and the developing roller contact 163. Thus, a developing bias that is electrically connected around the gear plate 134 and is output from the developing bias output terminal 144 is applied to the developing roller 38.

  The grid contact 164 is connected to a connection member 159 facing the grid bias output terminal 145 via a wiring 171 (see FIG. 12) as another bias lead. Thus, in a state where the process cartridge 18 is mounted on the main casing 2, the grid bias output terminal 145 of the high voltage substrate 135 and the grid electrode 77 of the process cartridge 18 are connected to the connection member 159 and the wiring 171 as shown in FIG. The grid bias is applied to the grid 75 of the scorotron charger 29 through the grid contact 164 and electrically connected to bypass the gear plate 134 and output from the grid bias output terminal 145.

  The cleaning contact 165 is connected to a connection member 160 facing the cleaning bias output terminal 146 via a wiring 172 (see FIG. 12) as another bias lead. As a result, in a state where the process cartridge 18 is mounted on the main casing 2, the cleaning bias output terminal 146 of the high-voltage substrate 135 and the cleaning electrode 80 of the process cartridge 18 are connected via the connection member 160, the wiring 172, and the cleaning contact 165. The cleaning bias that is electrically connected around the gear plate 134 and is output from the cleaning bias output terminal 146 is applied to the cleaning brush 31.

  Further, as shown in FIG. 14, the inner surface of the left frame 131 faces the drum ground electrode 73 disposed on the left side surface of the process cartridge 18 when the process cartridge 18 is mounted on the main casing 2. A drum earth contact 166 is provided at a position where the drum earth electrode 73 contacts. The drum ground contact 166 is electrically connected to the gear plate 134 and is grounded via the gear plate 134. Thus, when the process cartridge 18 is mounted on the main casing 2 and the drum ground electrode 73 provided on the left side surface of the process cartridge 18 contacts the drum ground contact 166, the drum shaft 33 of the photosensitive drum 28 is moved to the drum ground. It is grounded via the electrode 73, the drum ground contact 166 and the gear plate 134.

  Furthermore, a part of a lever driving force transmission gear 177 as a second gear that is rotatably supported by the left frame 131 is exposed on the inner side surface of the left frame 131 at the front lower end portion. When the paper feed tray 8 (see FIG. 1) is attached to the main casing 2, the input gear 67 is engaged with the lever driving force transmission gear 177. When the lever transmission gear 177 is rotated clockwise in FIG. 3 (counterclockwise in FIG. 14) by the driving force of the motor 137 (see FIG. 9), the input gear 67 is rotated counterclockwise, and further the lever The drive gear 68 is rotated clockwise, and the front end portion of the sheet pressing plate 14 is lifted by the lever 15 as described above. At this time, the lever driving force transmission gear 177 is rotationally driven counterclockwise in FIG. 14 to apply a force for urging the paper feeding tray 8 in the mounting direction to the input gear 67, whereby the paper feeding tray 8. The release from the main casing 2 is regulated by the cooperation of the lever driving force transmission gear 177 and a tray lock piece 179 described later.

  Further, as shown in FIG. 12, the upper end portion of the gear plate 134 is opposed to the connecting members 156, 158, 159, and 160 in the vertical direction, and is in the width direction (the left frame 131 and the right frame). The high voltage substrate 135 (discharge bias output terminal 142, transfer bias output terminal 143, development bias output terminal 144, grid bias output terminal 145 and cleaning bias output terminal 146) and the gear plate 134 An insulating sheet 173 for preventing leakage between the two is covered.

  The insulating sheet 173 is made of a translucent resin material, is formed in a shape corresponding to the outer shape of the upper end portion of the gear plate 134, and is opposed to the gear plate 134 in the width direction. An edge portion 197 that is bent from the upper end edge and the front end edge and extends in a direction opposite to the gear plate 134 is provided. The gear plate 134 and the high-voltage board 135 are electrically insulated by the facing surface portion 196, and the gear plate 134 and the connection members 156, 157, 158, 159, and 160 are electrically insulated by the edge portion 197. Is insulated.

  The main board 136 is a control board including a CPU for controlling the operation of each unit of the laser printer 1. As shown in FIG. 9, the main board 136 is formed in a substantially L shape in a side view, and on the outer surface of the left frame 131, a space formed on the rear side of the gear plate 134 and the high-voltage board 135. The gear plate 134 and the high voltage substrate 135 are arranged so as not to overlap.

On the other hand, as shown in FIG. 16, the right frame 132 has a substantially rectangular shape extending in the front-rear direction in a side view, and a low-pressure board 174 and a fan 175 are disposed on the outer side surface.
The low voltage substrate 174 is a power supply substrate for generating a low voltage for driving the motor 137 (see FIG. 9) by stepping down the voltage of the single-phase 100V supplied from the outside of the laser printer 1. The low-voltage board 174 is disposed so as to extend forward from the rear edge of the right frame 132 along the lower edge of the right frame 132 with the surface on which the transformer or the like is mounted facing the outer surface of the right frame 132. Yes. Further, the low-voltage board 174 is grounded (grounded) to the right frame 132 via a ground wire 176.

The fan 175 is for dissipating heat generated from the process cartridge 18 and the fixing unit 19 to the outside of the main casing 2. The fan 175 communicates the right frame 132 between the inner side in the width direction and the outer side in the width direction above the low-pressure board 174. Are arranged to be.
In addition, as shown in FIG. 17, a concave portion 178 that is recessed outward in the width direction is formed on the inner side surface of the right frame 132 at the front lower end, and in the concave portion 178, the paper feed tray 8 is formed. A tray lock piece 179 is provided as a lock mechanism for preventing detachment (see FIG. 1).

  As shown in FIG. 18, the tray lock piece 179 extends in the front-rear direction and is curvedly connected so that the distal end portion is directed to the outside of the recess 178, and the distal end portion of the curved arm 180. And an abutting portion 181 having a substantially U-shaped cross section. A base end portion of the bending arm 180 is swingably attached to a shaft 182 extending in the vertical direction in the recess 178. In addition, a spring (not shown) is connected to the bending arm 180, and the spring is always elastically biased in the direction in which the contact portion 181 protrudes out of the recess 178.

  When the paper feed tray 8 is attached to the main casing 2, the lock piece locking portion 71 provided on the paper feed tray 8 comes into contact with the contact portion 181 of the tray lock piece 179, and the tray lock piece 179 has its lock. As the piece locking portion 71 moves, the abutting portion 181 is pressed in a direction to retract into the recess 178 against the biasing force of a spring (not shown). When the lock piece locking portion 71 gets over the contact portion 181, the tray lock piece 179 returns to the direction in which the contact portion 181 protrudes from the recess 178 by the biasing force of a spring (not shown), and the contact portion 181. Is locked from the front side of the lock piece locking portion 71. Thereby, undesired detachment of the paper feed tray 8 from the main body casing 2 can be prevented.

Further, as shown in FIG. 17, on the inner surface of the right frame 132, when the paper feed tray 8 is mounted on the main casing 2, the ground connection hole 72 formed in the paper feed tray 8 (see FIG. 4). A pressing plate grounding contact 183 as a grounding contact that fits in is projected.
As shown in FIG. 19, the pressing plate ground contact 183 is formed by bending a wire into a substantially mountain shape, and extends in the width direction from between a slit 184 formed on the inner side surface of the right frame 132 in the front-rear direction. Projects inward. The pressing plate ground contact 183 can be elastically deformed in the width direction. When the paper feed tray 8 is attached to the main casing 2, the press plate ground contact 183 is elastically deformed so as to be retracted into the slit 184. Slide with the right side wall 63. When the paper feed tray 8 is attached to the main casing 2, the pressing plate ground contact 183 advances from the slit 184 and fits into the ground connection hole 72 of the paper feed tray 8. The metal sheet pressing plate 14 comes into contact.

  One end of the wire constituting the pressing plate ground contact 183 extends forward along the outer surface of the right frame 132 and bends further upward so as to face the downstream portion 89 of the guide plate 86 from below. Connected to the sheet metal 185. Furthermore, the sheet metal 185 is electrically connected to the low voltage substrate 174 (see FIG. 16) via a ground wire (not shown). As a result, when the paper feed tray 8 is mounted on the main casing 2 and the pressing plate ground contact 183 contacts the paper pressing plate 14, the paper pressing plate 14 is connected to the low voltage substrate via the pressing plate ground contact 183 and the sheet metal 185. It is grounded by being electrically connected to 174.

As shown in FIG. 20, the left frame 131 is provided with a coupling member 186 as an advancing / retracting member that is movably connected to a connecting hole 83 (see FIG. 7) of the input gear 82, and the coupling member 186. An arm 187 for advancing and retreating is provided.
The arm 187 is provided with a discharge bias output terminal 142, a development bias output terminal 144, a grid bias output terminal 145, and a cleaning bias output terminal 146 with respect to the coupling member 186 between the left frame 131 and the gear plate 134. The arm portion 188 provided on the front side opposite to the front side and extending in the front-rear direction and the cam portion 189 provided at the rear end portion of the arm portion 188 are integrally provided.

The cam portion 189 is formed with a long hole extending in the front-rear direction through which the coupling member 186 is inserted, and is formed thick in the width direction around the rear end portion of the long hole as shown in FIG. A retracting unit 190 is provided. Further, an advancing portion 191 that is formed thin in the width direction is provided around the front end portion of the long hole.
The arm 187 is supported so as to be movable in the front-rear direction along the left frame 131 in a state where the coupling member 186 is inserted into the long hole at the rear end. The arm 187 is provided so as to move in the front-rear direction in conjunction with opening and closing of the front cover 7.

  The coupling member 186 is disposed so as to face the connecting hole 83 of the input gear 82 of the process cartridge 18 attached to the main casing 2 in the width direction. The coupling member 186 receives a rotational driving force from a motor 137 (see FIG. 9) provided in the main casing 2. Further, the coupling member 186 is always urged toward the inner side in the width direction, that is, toward the connecting hole 83 by the urging spring 192 (see FIG. 20).

  When the front cover 7 is opened when the process cartridge 18 is attached to or detached from the main casing 2, the arm 187 moves forward in conjunction with the opening of the front cover 7, as shown in FIG. The retracting portion 190 engages with the coupling member 186. Then, the coupling member 186 retreats from the connection hole 83 of the input gear 82 against the urging force of the urging spring 192.

  When the front cover 7 is closed after the process cartridge 18 is attached to the main casing 2, the arm 187 moves rearward in conjunction with the closing of the front cover 7, as shown in FIG. The advancing portion 191 engages with the coupling member 186. Then, the coupling member 186 advances into the connection hole 83 of the input gear 82 by the urging force of the urging spring 192 and is connected so as not to be relatively rotatable. As a result, the driving force from the coupling member 186 is transmitted to the input gear 82, and the supply roller 37, the developing roller 38 and the agitator 43 are rotated by the driving force transmitted to the input gear 82.

  As described above, in the laser printer 1, the high-voltage board 135 is arranged so that at least a part thereof does not overlap the gear plate 134 in the width direction, and the high-pressure board 135 does not overlap the gear plate 134. Discharge bias output terminal 142, transfer bias output terminal 143, development bias output terminal 144, grid bias output terminal 145 and cleaning bias output terminal 146 are arranged. For this reason, the high voltage substrate 135 and the gear plate 134 are arranged on the outer surface of the left frame 131, so that the laser printer 1 can be reduced in size, but the leakage of the bias around the gear plate 134 can be prevented. it can.

  In addition, the discharge bias output terminal 142, the development bias output terminal 144, the grid bias output terminal 145, and the cleaning bias output terminal 146 are juxtaposed along the edge in a region that does not overlap the gear plate 134 of the high-voltage board 135 in the width direction. Therefore, a large distance between these terminals and the gear plate 134 can be ensured, and leakage of bias around the gear plate 134 can be further prevented.

  Further, an insulating sheet 173 is coated on the upper end portion of the gear plate 134, which is opposed to the connecting members 156, 158, 159, and 160 in the vertical direction and overlaps the high voltage substrate 135 in the width direction. Therefore, the high voltage substrate 135 and the gear plate 134 can be insulated. Therefore, bias leakage around the gear plate 134 can be reliably prevented.

In addition, since a distance between the discharge bias output terminal 142 and the transfer bias output terminal 143 is secured between the discharge bias output terminal 142 and the transfer bias output terminal 143, a discharge bias output terminal 142 is secured. And the transfer bias output terminal 143 can be prevented from leaking.
Further, the distance between the discharge bias output terminal 142 and the transfer bias output terminal 143 is based on the distance between the discharge bias output terminal 142 and the development bias output terminal 144, the grid bias output terminal 145, and the cleaning bias output terminal 146. Has been secured for a long time. Therefore, leakage between the discharge bias output terminal 142 and the transfer bias output terminal 143 can be further prevented.

Furthermore, since the rib 167 is interposed between the connecting member 156 facing the discharge bias output terminal 142 and the connecting member 158 facing the developing bias output terminal 144, leakage between them is prevented. be able to.
Moreover, the rib 167 also serves as a guide means for guiding the discharge bias output terminal 142 so as to abut against the connection member 156 when the high-voltage board 135 is attached to the outer surface of the left frame 131. While the 142 can be reliably brought into contact with the connecting member 156 and connected, the structure can be simplified and the number of parts can be reduced. Furthermore, since the charging transformer 139 has only to be rubbed against the front end surface 167A of the rib 167 at the time of connection, the workability when the discharge bias output terminal 142 is brought into contact with the connecting member 156 can be improved. it can. Further, since the rib 167 has an inclined surface 167C, when the discharge bias output terminal 142 is brought into contact with the connection member 156, the charging transformer 139 is reliably rubbed against the front end surface 167A of the rib 167. be able to.

  Further, since the wire contact 161, the transfer contact 162, the developing roller contact 163, the grid contact 164, and the cleaning contact 165 are provided on the inner surface of the left frame 131, these contacts, the discharge bias output terminal 142, and the transfer bias, respectively. The lengths of the wirings 168, 169, 170, 171 and 172 for connecting the output terminal 143, the developing bias output terminal 144, the grid bias output terminal 145 and the cleaning bias output terminal 146 can be shortened, and the wiring structure Simplification can be achieved.

  When the process cartridge 18 is mounted on the main casing 2, the drum ground electrode 73 provided on the left side surface of the process cartridge 18 contacts the drum ground contact 166 disposed on the inner side surface of the left frame 131, As a result, the drum shaft 33 of the photosensitive drum 28 can be grounded via the drum earth electrode 73, the drum earth contact 166 and the gear plate 134. Therefore, the grounding of the drum shaft 33 of the photosensitive drum 28 can be achieved with a simple configuration.

  Further, the arm 187 for advancing and retracting the coupling member 186 is provided with a discharge bias output terminal 142, a development bias output terminal 144, a grid bias output terminal 145, and a cleaning bias output terminal 146 with respect to the coupling member 186. Since it is provided on the front side opposite to the existing side, it is possible to prevent interference between the arm 187 moving in the front-rear direction and each bias output terminal.

In addition, the arm 187 is disposed in a space between the left frame 131 and the gear plate 134, and the space between the left frame 131 and the gear plate is effectively utilized as a space for disposing the arm 187. can do.
Further, since the high-voltage board 135 is arranged with the surface on which the charging transformer 139 and the like are mounted facing the gear plate 134 side, the charging transformer 139 and the like are prevented from protruding outward in the width direction of the high-voltage board 135. can do. Therefore, the width direction size of the laser printer 1 can be further reduced. As a result, the laser printer 1 can be further reduced in size.

  Further, the relatively tall components such as the charging transformer 139 are arranged in a portion of the high-voltage board 135 that does not overlap the gear plate 134 in the width direction. The gap between the gear plate 134 and the high-voltage board 135 can be narrowed by overlapping with the direction perpendicular to the direction. Therefore, the size of the laser printer 1 in the width direction can be further reduced, and the laser printer 1 can be further reduced in size.

  In addition, each bias output terminal of the high-voltage board 135 and each contact disposed on the inner surface of the left frame 131 bypass the gear plate 134 via the connection members 156, 157, 158, 159, and 160, and are electrically connected. Therefore, it is possible to eliminate the need for penetrating the wiring for connecting each bias output terminal and each contact to the gear plate 134. As a result, the wiring structure for electrical connection between each bias output terminal and each contact can be simplified.

In addition, the connecting members 156, 157, 158, 159, 160 can have a simple configuration in which a wire is wound.
Further, when the sheet feeding tray 8 is mounted on the main casing 2 and the pressing plate ground contact 183 contacts the sheet pressing plate 14, the sheet pressing plate 14 is connected to the low voltage substrate via the pressing plate ground contact 183 and the sheet metal 185. 174 can be electrically connected and grounded via its low voltage substrate 174. Therefore, the grounding of the sheet pressing plate 14 can be achieved with a simple configuration.

Furthermore, since the separation of the sheet feeding tray 8 from the main casing 2 is restricted by the cooperation of the lever driving force transmission gear 177 and the tray lock piece 179, the tray lock piece 179 is provided on the left frame 131. The configuration for regulating the separation of the paper feed tray 8 can be simplified.
Further, a wire contact 161, a transfer contact 162, a developing roller contact 163, a grid contact 164 and a cleaning contact 165 for electrical connection with the process cartridge 18 and a drive system (motor 137 and transmission gear 138) of the process cartridge 18 are provided. Since the centralized arrangement is made on the left frame 131, design restrictions on the right frame 132 can be reduced. For this reason, the right frame 132 can be designed so that the process cartridge 18 can be stably held. With such a design, the process cartridge 18 can be stably held. A stable supply of driving force can be achieved.

FIG. 2 is a side sectional view of a main part showing an embodiment of a laser printer as an image forming apparatus of the present invention, showing a state where a front cover is closed. It is principal part sectional drawing of the laser printer shown in FIG. 1, and shows the state which opened the front cover. FIG. 2 is a left side view of the paper feed tray shown in FIG. 1. FIG. 2 is a right side view of the paper feed tray shown in FIG. 1. It is a perspective view of the drum cartridge shown in FIG. FIG. 6 is a side sectional view of the drum cartridge shown in FIG. 5. FIG. 2 is a left side view of the process cartridge shown in FIG. 1. FIG. 2 is a plan view of a process cartridge, a left frame, and a right frame shown in FIG. 1. It is an outer side view of the left frame shown in FIG. It is a figure which shows the structure of the high voltage | pressure board | substrate shown in FIG. It is sectional drawing when cut | disconnecting by the cutting line AA shown in FIG. FIG. 10 is an outer side view of the left frame in a state where the high-voltage board shown in FIG. 9 is removed. It is sectional drawing when cut | disconnecting by the cutting line BB shown in FIG. FIG. 9 is an inner side view of the left frame shown in FIG. 8. It is sectional drawing when cut | disconnecting by the cutting line CC shown in FIG. It is an outer side view of the right frame shown in FIG. FIG. 9 is an inner side view of the right frame shown in FIG. 8. It is a principal part perspective view which shows the structure of the tray lock piece shown in FIG. It is a principal part perspective view which shows the structure of the press plate ground contact shown in FIG. FIG. 2 is a plan view of main parts of a process cartridge and a left frame shown in FIG. 1. It is a side view for demonstrating the advance / retreat operation | movement of the coupling member shown in FIG. 20, Comprising: (a) shows the advancing state of a coupling member, (b) shows the retracted state of a coupling member.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Laser printer 3 Paper 7 Front cover 14 Paper press board 28 Photosensitive drum 29 Scorotron type charger 30 Transfer roller 31 Cleaning brush 38 Developing roller 71 Lock piece latching part 74 Wire 75 Grid 131 Left frame 132 Right frame 134 Gear plate 135 High pressure Substrate 137 Motor 138 Transmission gear 139 Charging transformer 140 Transfer transformer 141 Development transformer 142 Discharge bias output terminal 143 Transfer bias output terminal 144 Development bias output terminal 145 Grid bias output terminal 146 Cleaning bias output terminal 156 Connection member 157 Connection member 158 Connection member 159 Connection member 160 Connection member 161 Wire contact 162 Transfer contact 163 Development roller contact 164 Grid contact 165 Cleaning contact 167 Rib 168 Wiring 169 Wiring 170 Wiring 171 Wiring 172 Wiring 173 Insulation sheet 174 Low voltage board 177 Lever driving force transmission gear 179 Tray lock piece 183 Press plate ground contact 186 Coupling member 187 Arm

Claims (21)

A first side wall and a second side wall disposed to face each other at a predetermined interval;
A process member disposed between the first side wall and the second side wall and used for an image forming process;
A driving source disposed on the first side wall side with respect to the process member and generating a driving force of the process member;
A first gear for transmitting a driving force from the driving source to the process member;
A gear plate made of a sheet metal disposed on the first side wall side with respect to the process member and supporting the first gear;
On the first side wall side with respect to the process member, it faces the gear plate so that at least a part does not overlap and at least a part overlaps in the opposing direction of the first side wall and the second side wall. A high pressure substrate disposed and generating a bias applied to the process member;
An image forming apparatus comprising: a power supply output terminal for outputting the bias, which is disposed in a portion of the high-voltage substrate that does not overlap the gear plate in the facing direction.   The image forming apparatus according to claim 1, wherein the power output terminal is disposed at an edge of a portion of the high-voltage board that does not overlap with the gear plate in the facing direction.   The image forming apparatus according to claim 1, further comprising an insulating sheet that covers a portion of the gear plate that overlaps the high-voltage substrate in the facing direction. The process member includes a photosensitive member, a wire, a charging unit for charging the photosensitive member, and a transfer unit for transferring a developer image carried on the photosensitive member to a recording medium,
The power supply output terminal comprises a discharge bias output terminal for outputting a discharge bias to the wire, and a transfer bias output terminal for outputting a transfer bias to the transfer means,
4. The image forming apparatus according to claim 1, wherein the discharge bias output terminal and the transfer bias output terminal are arranged with a distance at which no leakage occurs between the terminals. 5. . The process member includes a photosensitive member, a wire and a grid, and charging means for charging the photosensitive member, developing means for developing an electrostatic latent image formed on the photosensitive member, and the photosensitive member A transfer means for transferring a developer image carried on the body to a recording medium, and a cleaning means for cleaning the photoconductor,
The power output terminal includes: a discharge bias output terminal for outputting a discharge bias to the wire; a transfer bias output terminal for outputting a transfer bias to the transfer unit; a grid bias for the grid; A third bias output terminal for outputting a developing bias for the developing means or a cleaning bias for the cleaning means,
The distance between the discharge bias output terminal and the transfer bias output terminal is the distance between the discharge bias output terminal and the third bias output terminal, or the transfer bias output terminal and the third bias output terminal. The image forming apparatus according to claim 1, wherein the image forming apparatus is set to be longer than a distance between the image forming apparatus and the image forming apparatus. The process member includes a photosensitive member, a charging unit for charging the photosensitive member, a developing unit for developing an electrostatic latent image formed on the photosensitive member, and a developer carried on the photosensitive member. Transfer means for transferring an image to a recording medium,
The power output terminal includes a charging bias output terminal for outputting a charging bias to the charging unit, a transfer bias output terminal for outputting a transfer bias to the transfer unit, and a developing bias for the developing unit. Development bias output terminal for outputting
The distance between the charging bias output terminal and the transfer bias output terminal is the distance between the charging bias output terminal and the development bias output terminal, or between the transfer bias output terminal and the development bias output terminal. The image forming apparatus according to claim 1, wherein the image forming apparatus is set to be longer than a distance therebetween. The process member includes a photosensitive member, a wire and a grid, and charging means for charging the photosensitive member, developing means for developing an electrostatic latent image formed on the photosensitive member, and the photosensitive member A transfer means for transferring a developer image carried on the body to a recording medium, and a cleaning means for cleaning the photoconductor,
The power supply output terminal includes a discharge bias output terminal for outputting a discharge bias to the wire, a transfer bias for the transfer unit, a grid bias for the grid, a development bias for the development unit, or a cleaning bias for the cleaning unit. And other bias output terminal for outputting
A discharge bias conductor disposed on the first side wall and connected to the discharge bias output terminal;
Another bias conducting wire disposed on the first side wall and connected to the other bias output terminal;
A shielding member interposed between the discharge bias conducting wire and the other bias conducting wire on the first side wall to prevent leakage between the discharge bias conducting wire and the other bias conducting wire. The image forming apparatus according to claim 1, wherein the image forming apparatus is an image forming apparatus. The process member includes a photosensitive member, a charging unit for charging the photosensitive member, a developing unit for developing an electrostatic latent image formed on the photosensitive member, and a developer carried on the photosensitive member. Transfer means for transferring an image to a recording medium,
The power supply output terminal includes a charging bias output terminal for outputting a charging bias to the charging unit, and another bias output terminal for outputting a transfer bias for the transfer unit or a developing bias for the developing unit. And
A charging bias conductor disposed on the first side wall and connected to the charging bias output terminal;
Another bias conducting wire disposed on the first side wall and connected to the other bias output terminal;
A shielding member interposed between the charging bias conducting wire and the other bias conducting wire on the first side wall to prevent leakage between the charging bias conducting wire and the other bias conducting wire. The image forming apparatus according to claim 1, wherein the image forming apparatus is an image forming apparatus. The charging means includes a wire and a grid,
The charging bias output terminal is a discharge bias output terminal for outputting a discharge bias to the wire,
9. The image forming apparatus according to claim 8, wherein the charging bias lead is a discharge bias lead to which the discharge bias output terminal is connected.   The said shielding member serves as a guide means which guides the movement of the said discharge bias output terminal, when connecting the said discharge bias output terminal with respect to the said conducting wire for discharge bias, The Claim 7 or 9 characterized by the above-mentioned. The image forming apparatus described. The high-voltage board is mounted with a charging transformer for generating the discharge bias,
The discharge bias output terminal is disposed on the charging transformer,
The said shielding member is arrange | positioned in the position which rubs with the said transformer for charging, when connecting the said discharge bias output terminal with respect to the said conducting wire for discharge bias, It is characterized by the above-mentioned. Image forming apparatus. The process member includes a photoreceptor,
The image forming apparatus according to claim 1, wherein the photoconductor is grounded through the gear plate. An opening and closing cover for opening and closing an opening formed between the first side wall and the second side wall;
The connection position that advances from the first side wall in the facing direction and can transmit the driving force to the process member, and retracts from the connecting position to the outside in the facing direction to release the transmission of the driving force to the process member. An advancing and retracting member capable of advancing and retracting to a release position to be
An arm that is disposed between the opening / closing cover and the advance / retreat member and moves the advance / retreat member in conjunction with opening / closing of the opening / closing cover;
The image forming apparatus according to claim 1, wherein the power output terminal is disposed on a side opposite to a side where the arm is provided with respect to the advance / retreat member.   The image forming apparatus according to claim 1, wherein a transformer is mounted on the high-voltage board so as to protrude toward the gear plate. The high-pressure substrate is at least partially arranged to face the gear plate in the facing direction,
The image forming apparatus according to claim 14, wherein the transformer is mounted on a portion that does not overlap the gear plate in the facing direction.   The contact point disposed on the first side wall side with respect to the process member and connected to apply the bias to the process member is provided. Image forming apparatus. The first side wall and the high-pressure board are disposed to face each other with the gear plate interposed therebetween,
The image forming apparatus according to claim 16, further comprising a connecting member for electrically connecting the contact and the high-voltage board while avoiding the gear plate.   The image forming apparatus according to claim 17, wherein the connection member is made of a wire. An opening and closing cover for opening and closing an opening formed between the first side wall and the second side wall;
The connection position that advances from the first side wall in the facing direction and can transmit the driving force to the process member, and retracts from the connecting position to the outside in the facing direction to release the transmission of the driving force to the process member. An advancing and retracting member capable of advancing and retracting to a release position to be
An arm that is disposed between the opening / closing cover and the advance / retreat member and moves the advance / retreat member in conjunction with opening / closing of the opening / closing cover;
The image forming apparatus according to claim 17, wherein the arm is disposed between the first side wall and the gear plate. A low-pressure substrate that is disposed on the second side wall with respect to the process member and generates a voltage lower than the high-voltage substrate;
A mounting plate for mounting a recording medium on which an image is recorded by the process member;
The ground contact according to any one of claims 1 to 19, further comprising a ground contact that is electrically connected to the low-voltage board, protrudes from the second side wall, and contacts the mounting plate. The image forming apparatus described in 1. A mounting plate for mounting a recording medium on which an image is recorded by the process member;
A cassette that houses the mounting plate and is detachably mounted between the first side wall and the second side wall;
A locking mechanism provided on the second side wall for restricting detachment of the cassette;
A second gear provided on the first side wall for moving the mounting plate from a mounting position for mounting the recording medium to a transport position for transporting the recording medium;
The second gear is provided to rotate in a direction that urges the cassette in the mounting direction,
21. The cassette according to claim 1, wherein separation of the cassette from between the first side wall and the second side wall is restricted by cooperation of the lock mechanism and the second gear. An image forming apparatus according to claim 1.

Images