JP7207940B2 - image forming device - Google Patents

Description

The present invention relates to an electrophotographic image forming apparatus.

2. Description of the Related Art In printers, which are electrophotographic image forming apparatuses, the following exposure methods are generally known. That is, an exposure method is generally known in which a photosensitive drum is exposed using an exposure head using an LED (Light Emitting Diode), an organic EL (Organic Electro Luminescence), or the like to form a latent image. The exposure head has a light-emitting element array arranged in the longitudinal direction of the photosensitive drum, and a rod lens array that forms an image of the light from the light-emitting element array on the photosensitive drum. LEDs and organic ELs are known to have a surface emitting shape in which the direction of light emitted from the light emitting surface is the same as that of the rod lens array. Here, the length of the light emitting element row is determined according to the width of the image area on the photosensitive drum, and the interval between the light emitting elements is determined according to the resolution of the printer. For example, for a 1200 dpi printer, the pixel spacing is 21.16 μm, so the spacing between light emitting elements also corresponds to 21.16 μm. A printer using such an exposure head uses fewer parts than a laser scanning printer that scans a photosensitive drum with a laser beam deflected by a rotating polygonal mirror. easy to convert. Also, in a printer using an exposure head, noise caused by rotation of a rotating polygon mirror is reduced.

Conventionally, an image forming apparatus having a configuration including a plurality of photosensitive drums, a plurality of LED exposure heads, and a support that supports each photosensitive drum and each LED exposure head and can be stored in and pulled out of an image forming apparatus. It has been known. For example, Patent Document 1 proposes the following configuration of such an image forming apparatus. That is, each LED exposure head is electrically connected to a control board (hereinafter referred to as a main board) provided in the main body of the image forming apparatus via a flat cable, or connected to the main board via a relay board provided on the support. A configuration has been proposed in which it is electrically connected to the

JP 2012-144019 A

As described above, in an image forming apparatus having a configuration in which a relay board is provided on a support and the body board and each LED exposure head are electrically connected, the body board and the relay board are connected by a cable. . In such a configuration, it is necessary to set the length of the cable to the extent that the support can be pulled out from the image forming apparatus. In the case of a configuration in which a main board provided in the main body of the image forming apparatus and a relay board provided in the support are connected by a cable, the longer the cable, the more likely it is to be affected by noise.

In order to solve the above problems, the present invention has the following configuration.

(1) An apparatus main body having an opening formed on a side surface, a drum cartridge having a rotatable photosensitive drum, an optical print head having a light emitting element for emitting light for exposing the photosensitive drum, and the photosensitive drum. It has a first wall portion that supports one end side of the optical print head in the rotation axis direction and a second wall portion that supports the other end side of the optical print head in the rotation axis direction, and is attached to the apparatus main body. a support portion movable between a mounted position and a drawn position drawn out from the mounted position through the opening; a first connector provided on the device main body; and the support portion positioned at the mounted position. a second connector that is connected to the first connector when the support is at the pulled-out position and is disconnected from the first connector when the support is at the pulled-out position; in order to control driving of the light emitting element based on a drive signal sent via the first connector when the first connector and the second connector are connected to each other. a control board provided on either the first wall or the second wall , wherein the first connector is provided on a body board provided in the apparatus body. image forming device.

(2) an apparatus main body having an opening formed on a side thereof; a drum cartridge having a rotatable photosensitive drum; an optical print head having a light emitting element for emitting light for exposing the photosensitive drum; It has a first wall portion that supports one end side of the optical print head in the rotation axis direction and a second wall portion that supports the other end side of the optical print head in the rotation axis direction, and is attached to the apparatus main body. a support portion movable between a mounted position and a drawn position drawn out from the mounted position through the opening; a first connector provided on the device main body; and the support portion positioned at the mounted position. a second connector that is connected to the first connector when the support is at the pulled-out position and is disconnected from the first connector when the support is at the pulled-out position; in order to control driving of the light emitting element based on a drive signal sent via the first connector when the first connector and the second connector are connected to each other. and a control board provided on a third wall portion that is continuous with ends of the first wall portion and the second wall portion on the upstream side in the direction in which the support portion is pulled out.

According to the present invention, it is possible to shorten the length of the cable that connects the main substrate and the relay substrate.

Schematic cross-sectional view showing the configuration of an image forming apparatus according to an embodiment FIG. 4 is a diagram for explaining the positional relationship between the exposure head and the photosensitive drum of the embodiment, and a diagram for explaining the configuration of the exposure head; Schematic diagram of a drive substrate of an embodiment and a diagram for explaining the structure of a surface emitting element array chip Control block diagram of the main body board, LED control board, and drive board of the embodiment FIG. 4 is a diagram for explaining a cable connection configuration when the image forming unit of the embodiment is housed in the image forming apparatus; FIG. 4 is a diagram for explaining a cable connection configuration when the image forming unit of the embodiment is housed in the image forming apparatus; FIG. 4 is a diagram for explaining a cable connection configuration when the image forming unit of the embodiment is pulled out from the image forming apparatus;

BEST MODE FOR CARRYING OUT THE INVENTION Below, embodiments of the present invention will be described in detail with reference to the drawings.

[Configuration of Image Forming Apparatus]
FIG. 1A is a schematic cross-sectional view showing the configuration of an electrophotographic image forming apparatus according to this embodiment. The image forming apparatus 100 shown in FIG. 1A includes an image forming unit 400, a fixing unit 404, a paper feeding/conveying unit 405, and an opening of the image forming unit 400 formed on the side surface of the image forming apparatus 100. It has a door 410 and the like. In FIGS. 1A and 1B, “front” (the right side of the paper) indicates the front direction of the image forming apparatus 100 , and “back” (the left side of the paper) indicates the rear direction of the image forming apparatus 100 . represents. Also, “top” (upper side as viewed in the paper) indicates the top surface direction of the image forming apparatus 100 , and “lower” (lower side as viewed in the paper surface) indicates the bottom surface direction of the image forming apparatus 100 . Also in FIGS. 5 and 7, the directions indicated by "front", "rear", "up", and "down" are the same, and descriptions of FIGS. 5 and 7 will be omitted.

The image forming unit 400, which is a support unit, has four process cartridges (image forming units) with different toner colors of yellow (Y), magenta (M), cyan (C), and black (K) inside. It is a unit that can be pulled out and stored from the image forming apparatus 100 . The image forming section 400 is open at the top and bottom, has a side wall portion 430 (see FIG. 6) on the outer peripheral side surface, and each process cartridge is supported by the side wall portion 430 . Each process cartridge has the same configuration and includes a photosensitive drum 102 , charger 402 and developer 403 . The rotatable photosensitive drum 102 and charger 402 constitute a drum cartridge. Further, an exposure head 106 is arranged so as to face the photosensitive drum 102 of each process cartridge in the rotational axis direction. The suffixes Y, M, C, and K at the end of the reference numerals indicate members of yellow, magenta, cyan, and black process cartridges, respectively. In the following description, suffixes are omitted unless a specific process cartridge is described.

When image formation is started, in each process cartridge, the charger 402 uniformly charges the surface of the photosensitive drum 102 rotating in the arrow direction (counterclockwise direction) in the figure. Subsequently, the exposure head 106 causes the chip surface of the LED array to emit light according to irradiation data from an LED control board 501 (see FIG. 4), which will be described later. Light is collected to form an electrostatic latent image. The developing device 403 attaches toner to the electrostatic latent image on the photosensitive drum 102 and develops it to form a toner image.

The transfer belt 406 is an endless belt that is provided between the paper feed cassette 408 and each photosensitive drum 102, is stretched over a plurality of rollers, and rotates in the arrow direction (clockwise direction) in the figure. In addition, a transfer roller is arranged inside the transfer belt 406 so as to sandwich the transfer belt 406 at a position facing each photosensitive drum 102 . A toner image formed on the photosensitive drum 102 of each process cartridge is transferred to a transfer belt 406 in contact with the photosensitive drum 102 by a transfer roller. A toner image is formed.

On the other hand, in accordance with image formation in each process cartridge of the image forming unit 400 , a sheet S as a recording material is fed from the paper feed cassette 408 of the paper feed/conveyance unit 405 and directed to the secondary transfer device 407 . transported through the transport path. In the secondary transfer device 407, the toner image formed on the transfer belt 406 is transferred onto the sheet S conveyed. Then, the sheet S onto which the toner image has been transferred is conveyed to the fixing section 404 by the conveying belt 412 . In the fixing unit 404 , the unfixed toner image on the conveyed sheet S is subjected to pressure and heat treatment, and the toner image is fixed on the sheet S. FIG. After that, the sheet S on which the toner image is fixed is conveyed along the conveying path and discharged to the discharge tray 409 .

FIG. 1B is a cross-sectional view showing a state in which the imaging unit 400 is pulled out from the image forming apparatus 100. As shown in FIG. FIG. 1(b) shows an operation for opening the rotatably provided door 410 shown in FIG. A state in which the image forming unit 400 is pulled out of the image forming apparatus 100 is shown. In the image forming apparatus 100 of this embodiment, a guide frame 420 serving as a guide portion for guiding the image forming unit 400 in the front-rear direction in FIG. It is provided inside the device 100 . The guide frame 420 is provided so as to face three side walls 430 of the imaging section 400 excluding the side wall facing the door 410 (front side wall in the figure).

When the door 410 is opened, the photosensitive drum 102 of each process cartridge is separated from the transfer belt 406 by a mechanism (not shown). Similarly, each exposure head 106 is also moved upward in the drawing (top surface direction) by a mechanism (not shown) to separate from the photosensitive drum 102 of each process cartridge. On the other hand, when the door 410 is closed, each exposure head 106 is moved downward in the drawing (toward the bottom) by a mechanism (not shown) to a position where the surface of the photosensitive drum 102 of each process cartridge is exposed. do.

FIG. 1C is a cross-sectional view showing a state in which the yellow (Y) process cartridge is removed from the image forming unit 400. FIG. The process cartridge of this embodiment integrates the photosensitive drum 102, charger 402, and developing device 403, and is configured to be easily removed from the image forming section 400 and replaced.

[Configuration of Exposure Head]
Next, the exposure head 106, which is an optical print head that exposes the photosensitive drum 102, will be described with reference to FIG. FIG. 2A is a perspective view showing the positional relationship between the exposure head 106 and the photosensitive drum 102, and FIG. 2B shows the internal structure of the exposure head 106 and how the light beam from the exposure head 106 passes through the rod lens array. FIG. 2 is a diagram for explaining how light is focused on a photosensitive drum 102 by a light 203; As shown in FIG. 2A, the exposure head 106 is attached to the image forming apparatus 100 by an attachment member (not shown) at a position facing the photosensitive drum 102, which rotates in the direction of the arrow. (Fig. 1).

As shown in FIG. 2B, the exposure head 106 comprises a driving substrate 202, a surface emitting element array element group 201 mounted on the driving substrate 202, a rod lens array 203, and a housing 204. As shown in FIG. A rod lens array 203 and a driving substrate 202 are attached to the housing 204 . The rod lens array 203 converges the light flux emitted from the surface emitting element array element group 201 onto the photosensitive drum 102 . At the factory, the exposure head 106 alone is assembled and adjusted, and the focus and light amount of each spot are adjusted. Here, assembly adjustment is performed so that the distance between the photosensitive drum 102 and the rod lens array 203 and the distance between the rod lens array 203 and the surface emitting element array element group 201 are at predetermined intervals. As a result, light from the surface emitting element array element group 201 forms an image on the photosensitive drum 102 . Therefore, when adjusting the focus at the factory, the mounting position of the rod lens array 203 is adjusted so that the distance between the rod lens array 203 and the surface emitting element array element group 201 becomes a predetermined value. Further, when adjusting the amount of light in the factory, the light emitting elements of the surface light emitting element array element group 201 are sequentially caused to emit light, and the light condensed on the photosensitive drum 102 via the rod lens array 203 reaches a predetermined light amount. The driving current of each light emitting element is adjusted so that

[Structure of Surface Emitting Element Array Element Group]
FIG. 3 is a diagram for explaining the surface emitting element array element group 201. As shown in FIG. FIG. 3A is a schematic diagram showing the configuration of the surface of the driving substrate 202 on which the surface emitting element array element group 201 is mounted, and FIG. is a schematic diagram showing the configuration of the surface (second surface) opposite to the surface (first surface) on which is mounted.

As shown in FIG. 3A, in the surface emitting element array element group 201 mounted on the driving substrate 202, 29 surface emitting element array chips 1 to 29 are staggered along the longitudinal direction of the driving substrate 202. It has a configuration arranged in two rows in a shape. In FIG. 3A, the vertical direction indicates the sub-scanning direction (the rotation direction of the photosensitive drum 102), which is the first direction, and the horizontal direction indicates the main scanning direction, which is the second direction perpendicular to the sub-scanning direction. indicate direction. Inside each surface emitting element array chip, each element of the surface emitting element array chip having a total of 516 light emitting points is arranged at a predetermined resolution pitch in the longitudinal direction of the surface emitting element array chip. In this embodiment, the pitch of each element of the surface emitting element array chip is approximately 21.16 μm (≈2.54 cm/1200 dots), which is the pitch of the first resolution of 1200 dpi. As a result, the interval from end to end of the 516 light emitting points in one surface emitting element array chip is approximately 10.9 mm (≈21.16 μm×516). The surface emitting element array element group 201 is composed of 29 surface emitting element array chips. The number of light emitting elements that can be exposed in the surface emitting element array element group 201 is 14,964 elements (=516 elements x 29 chips), corresponding to an image width of approximately 316 mm (approximately 10.9 mm x 29 chips) in the main scanning direction. It is possible to form an image with

FIG. 3(c) is a view showing the boundary between chips of the surface emitting element array chips arranged in two rows in the longitudinal direction. It is the longitudinal direction of the group 201 . As shown in FIG. 3(c), wire bonding pads to which control signals are input are arranged at the ends of the surface emitting element array chip, and signals input from the wire bonding pads control the transfer section and the light emission. The element is driven. Also, the surface emitting element array chip has a plurality of light emitting elements. Even at the boundary between the surface emitting element array chips, the pitch of the light emitting elements in the longitudinal direction (the distance between the center points of the two light emitting elements) is approximately 21.16 μm, which is the pitch of the resolution of 1200 dpi. . In addition, the surface emitting element array chips arranged in two vertical rows have an interval (indicated by an arrow S in the figure) between the light emitting points of the upper and lower surface emitting element array chips of about 84 μm (4 pixels at 1200 dpi, 8 pixels at 2400 dpi). are arranged so that the distance is an integral multiple of each resolution of minutes).

Further, as shown in FIG. 3B, on the surface of the driving substrate 202 opposite to the surface on which the surface emitting element array element group 201 is mounted, driving units 303a and 303b and a connector 305 are mounted. there is Driving units 303a and 303b arranged on both sides of the connector 305 drive the surface emitting element array chips 1 to 15 and the surface emitting element array chips 16 to 29, respectively. Drive units 303a and 303b are connected to connector 305 via patterns 304a and 304b, respectively. Signal lines, power supply voltage lines, and ground lines for controlling the drive units 303a and 303b from an LED control board 501 (see FIG. 4), which will be described later, are connected to the connector 305, and are connected to the drive units 303a and 303b. . Wiring for driving the surface emitting element array element group 201 passes through the inner layer of the driving substrate 202 from the driving units 303a and 303b, and the surface emitting element array chips 1 to 15 and the surface emitting element array chips 16 to 29 are connected to the surface emitting element array chips 1 to 15. It is connected to the.

[Configuration of main board and LED control board]
FIG. 4 is a block diagram illustrating the configuration of the main body board 500, the LED control board 501, and the drive boards 202 (202Y, 202M, 202C, 202K) mounted on the respective exposure heads 106 (106Y, 106M, 106C, 106K). is. The main board 500 is a printed board provided with a control circuit for controlling the image forming apparatus 100 during image formation. The main board 500 has a main CPU 510 that controls image formation, an image control section 503 that performs image processing, and a connector 540 for connecting a cable 520 . Upon receiving an image forming instruction from the main CPU 510 , the image control unit 503 outputs image data, which is a drive signal for forming an image, to the LED emission control unit 504 of the LED control board 501 . The image data includes pixel data corresponding to the surface emitting elements of the surface emitting element array chips 1 to 29 mounted on the driving substrate 202 of each exposure head 106 . The image control unit 503 then outputs the image data to the LED emission control unit 504 in a predetermined order. Various control circuits for controlling image formation are provided on the main substrate 500, but only the control circuit for controlling the exposure head 106 is shown here, and the other control circuits are omitted. .

The LED control board 501 as a control board has an LED emission control section 504 and a connector 530 as a second connector for connecting the cable 520 . The LED light emission control unit 504 receives image data output from the image control unit 503 of the main body substrate 500, and controls the surface light emitting element array chips 1 to 29 mounted on each exposure head 106 based on the received image data. Irradiation data corresponding to each surface emitting element is generated. The image data from the image control unit 503 includes color information indicating which color is yellow (Y), magenta (M), cyan (C), or black (K). Based on the color information, the LED light emission control unit 504 outputs irradiation data of the photosensitive drum 102 corresponding to each color to the drive substrate 202 of the exposure head 106 on which the surface emitting element array chips 1 to 29 of each color are mounted. The driving units 303 a and 303 b mounted on the driving substrate 202 of each exposure head 106 perform lighting control of the surface emitting elements based on the irradiation data received from the LED emission control unit 504 to expose the photosensitive drum 102 .

The LED control board 501 also functions as a relay board for electrically connecting the main body board 500 and the driving board 202 of the exposure head 106 . Specifically, as shown in FIG. 4, cables 505 (505Y, 505M, 505C, 505K) are provided between the LED control board 501 and the drive boards 202 (202Y, 202M, 202C, 202K) of the exposure head 106. Individually connected. A serial signal, power supply voltage, ground, etc., which are irradiation data, are transmitted from the LED light emission control unit 504 of the LED control board 501 to the drive board 202 of each exposure head 106 via the cable 505 . Specifically, as shown in FIG. 4, between the LED control board 501 and the drive board 202 on which the surface emitting element array chips of each color are mounted, a total of 28-pin cables for serial signals, power lines, and ground lines are connected. 505 are individually connected.

Also, the body board 500 and the LED control board 501 are connected via a cable 520 that is a flexible flat cable. Specifically, a connector 521 is provided at one end of the cable 520, and a connector 522, which is a first connector, is provided at the other end. The connector 521 is connected to the connector 540 of the main substrate 500 , and the connector 522 is connected to the connector 530 of the LED control substrate 501 , thereby electrically connecting the main substrate 500 and the LED control substrate 501 . The cable 520 may be a bundle of single-core cables.

Here, the connector 522 and the main substrate 500 do not necessarily have to be connected via the cable 520 . A connector 522 may be provided on the body board 500 (on the body board), and a connector 530 provided on the LED control board 501 may be connected here.

In order to transmit the image data via the cable 520, a total of 10 signal lines are used for serializing/deserializing (SerDes) the image data of each color and transmitting the image data. The breakdown of the 10 signal lines is 4 pairs of differential signal lines (2 x 4) of yellow (Y), magenta (M), cyan (C), and black (K), and a power supply voltage line (1). and a ground line (one line). In order to reduce the number of wires for data transmission between the main body substrate 500 and the LED control substrate 501, a serializer that converts parallel data signals into high-speed serial signals and a serializer that converts high-speed serial signals into parallel data signals are used. A transforming deserializer is used. Accordingly, the image data of each color can be transmitted through the cable 520 composed of a total of 10 signal lines.

[Configuration of cable connection between main board and LED control board]
FIG. 5 is a schematic cross-sectional view of the image forming apparatus 100 in which the image forming unit 400 is housed. 5 is a diagram illustrating a connection configuration of a cable 520; FIG. The body substrate 500 is fixed to a panel member 550 (see FIG. 6), which will be described later, but the panel member 550 is not shown in FIG.

The LED control board 501 is installed at the “rear” end of the side wall 430 on the front side of the drawing of the image forming unit 400 . On the other hand, the main board 500 is fixed on a panel member 550 provided between the guide frame 420 and the housing of the image forming apparatus 100 . It is installed near the bottom. The main board 500 also has a connector 540 for connecting the connector 521 of the cable 520 , and the LED control board 501 has a connector 530 for connecting the connector 522 of the cable 520 . Since the connector 540 is provided on the surface of the main substrate 500 facing the guide frame 420, it is indicated by a dashed line in FIG.

Next, the connection of the cable 520 between the main board 500 and the LED control board 501 will be described. As described above, the ends of cable 520 are provided with connectors 521 and 522 , connector 521 is connected to connector 540 of main substrate 500 , and connector 522 is connected to connector 530 of LED control substrate 501 . As the cable 520, a bundle of flat cables or single-core cables is used, and FIG. 5 shows the cable 520 using the bundle. The connector 521 is a board-to-cable bundle connector. The connector 522 is a panel mount type connector and fixed to the guide frame 420 . Also, in this embodiment, the connector 522 uses a drawer connector. The drawer connector has a guide shape in order to achieve easy and reliable connection with the connector to be connected (connector 530 in this embodiment).

When the image forming unit 400 is housed in the image forming apparatus 100 and fixed at the mounting position in which it is mounted, the connector 522 on the cable 520 side and the connector 530 mounted on the LED control board 501 are connected. are fitted and electrically connected. On the other hand, when the image forming unit 400 is pulled out from the image forming apparatus 100, the connector 530 on the LED control board 501 is disconnected from the connector 522 of the cable 520 fixed to the guide frame 420, and the electrical connection is cut off. state. Since the connector 522 of the cable 520 is fixed to the guide frame 420 in this manner, the cable length of the cable 520 can be changed according to the state in which the image forming unit 400 is housed in or pulled out of the image forming apparatus 100. It never changes. That is, the cable length of the cable 520 may be a fixed length that allows the connector 521 to connect to the connector 540 of the main substrate 500 from the position where the connector 522 is fixed. As a result, there is no need to provide a space for storing the extra length of the flat cable, and there is no need to bend the flat cable for storing it, so that the cable is not broken due to bending. Although a drawer connector is used as the connector 522 here, other connectors may be used as long as they are electrically connectable.

[Cable connection of main board, LED control board, drive board]
FIG. 6 is a schematic diagram showing a state in which the image forming unit 400 is housed in the image forming apparatus 100, and shows the body board 500 and the LED control board 501 when viewed from above (upper side in the vertical direction) of the image forming apparatus 100. is a schematic diagram showing the shape of a cable 520 that connects the . In FIG. 6 , “front” (right side of the paper) indicates the front direction of the image forming apparatus 100 , and “back” (left side of the paper) indicates the back direction of the image forming apparatus 100 . Also, “left” indicates the left direction viewed from the front of the image forming apparatus 100 , and “right” indicates the right direction viewed from the front of the image forming apparatus 100 .

As shown in FIG. 6, the imaging unit 400 has a guide frame 420 and a side wall portion 430 facing the closed door 410 . The side wall portion 430 is composed of four side wall portions 430F, 430RS, 430LS and 430R. The side wall portion 430F is a side wall portion facing the closed door 410 . The side wall portion 430RS (first wall portion or second wall portion) is a side wall portion facing the “right” side guide frame 420, and the side wall portion 430LS (second wall portion or first wall portion) is a side wall portion facing the “left” side. ] is a side wall portion facing the guide frame 420 on the side of . Further, a side wall portion 430R (third wall portion) continuous with the side wall portion 430RS and the side wall portion 430LS is a side wall portion facing the guide frame 420 on the “rear” side. In this embodiment, the LED control board 501 is mounted on the guide frame 420 at the end of the image forming section 400 on the “rear” side of the side wall portion 430LS (on the upstream side in the direction of drawing out the image forming section 400 from the drawing port). is installed on the side facing the Also, exposure heads 106 (106Y, 106M, 106C, 106K) are arranged at positions facing the photosensitive drums 102 (102Y, 102M, 102C, 102K) (not shown in FIG. 6) installed in the imaging unit 400. It is The LED control board 501 and the exposure heads 106 (106Y, 106M, 106C, 106K) are connected via cables 505 (505Y, 505M, 505C, 505K). One end of the exposure head 106 in the longitudinal direction is supported by the side wall 430RS, and the other end is supported by the side wall 430LS.

LED control board 501 has connector 530 for connecting cable 520 . The connector 522 of the cable 520 connected to the connector 530 is a hole provided in the guide frame 420 at a position where the connector 530 comes into contact with the guide frame 420 when the image forming unit 400 is housed in the image forming apparatus 100. fixed to the part. Therefore, when the image forming unit 400 is housed in the image forming apparatus 100, the connector 530 of the LED control board 501 is fitted with the connector 522 of the cable 520, and the body board 500 and the LED control board 501 are electrically connected. is connected to

Main substrate 500 is fixed to panel member 550 provided between guide frame 420 and the housing of image forming apparatus 100 . The body substrate 500 is arranged on one side of the image forming unit 400 in the rotation axis direction of the photosensitive drum 102 . Further, the body board 500 has a connector 540 for connecting with the connector 521 of the cable 520 . The connector 540 is provided on the surface of the main substrate 500 facing the guide frame 420 .

When the image forming unit 400 is housed in the image forming apparatus 100, the connectors 521 and 522 provided on the cable 520 are connected to the connector 540 of the main substrate 500 and the connector 530 of the LED control substrate 501, respectively. It has become. As shown in FIG. 6, the cable 520 is rotated along with the movement of the image forming unit 400 regardless of whether the image forming unit 400 is housed in the image forming apparatus 100 or pulled out from the image forming apparatus 100 . never Therefore, the length of the cable 520 may be the shortest length that allows connection between the connector 540 of the main substrate 500 and the connector 530 of the LED control substrate 501 .

[Cable connection of main board, LED control board, drive board]
FIG. 7 is a schematic cross-sectional view of the imaging unit 400 pulled out from the image forming apparatus 100, and is a diagram for explaining the connection configuration of the main substrate 500, the LED control substrate 501, and the cable 520. FIG. FIG. 7 shows a state in which the image forming section 400 is pulled out from the drawer port of the image forming apparatus 100 to the maximum drawer position in order to take out a process cartridge that can be accommodated in the image forming section 400 . . Although the main substrate 500 is fixed to a panel member 550 (FIG. 6), the panel member 550 is not shown in FIG.

In this embodiment, the connector 522 of the cable 520 connecting between the main board 500 and the LED control board 501 is a panel mount type drawer connector and is fixed to the guide frame 420 as shown in FIG. . Therefore, when the image forming unit 400 is pulled out from the image forming apparatus 100, the connector 530 on the LED control board 501 is disconnected from the connector 522 of the cable 520, and the electrical connection is released. there is 5 and 6, the connector 530 on the LED control board 501 is connected to the connector 522 of the cable 520, and the LED control board 501 is connected. and main substrate 500 are electrically connected. In this way, image forming unit 400 can move along guide frame 420 between the mounted position where image forming unit 400 is mounted on image forming apparatus 100 and the pulled-out position where image forming unit 400 is pulled out from image forming apparatus 100 . , and is detachable from the image forming apparatus 100 .

Further, in this embodiment, the main substrate 500 is installed between the guide frame 420 on the side facing the side wall portion 430LS and the housing of the image forming apparatus 100, but the installation position is limited to this. is not. The body substrate 500 is, for example, between the guide frame 420 on the side facing the side wall portion 430RS and the housing of the image forming apparatus 100, and between the guide frame 420 on the side facing the side wall portion 430R and the housing of the image forming apparatus 100. It may be installed on the bottom surface of the housing of the image forming apparatus 100 during . In this embodiment, the LED control board 501 is installed at the "rear" end of the side wall 430LS of the imaging unit 400 (FIG. 5), but the installation position is not limited to this. The LED control board 501 may be installed, for example, at the “rear” end of the side wall portion 430RS of the image forming section 400 or may be installed at the side wall portion 430R of the image forming section 400 . Note that the connector 522 is provided on the LED control board 501 of the guide frame 420 so that the LED control board 501 and the main body board 500 are electrically connected when the imaging unit 400 is housed in the image forming apparatus 100 . is fixed at a position facing the connector 530 of the .

Furthermore, in the embodiment described above, the body substrate 500 and the LED control substrate 501 are connected via the cable 520 . For example, when the body substrate 500 is arranged so that the connector 540 of the body substrate 500 is installed at the position of the connector 522 of the cable 520, when the imaging unit 400 moves to the mounting position, the body substrate 500 and the LED It is directly connected to the control board 501 . That is, the body substrate 500 and the LED control substrate 501 are connected via the connectors 540 and 530 provided on the respective substrates. This eliminates the need for cable 520 and reduces costs associated with cable 520 .

According to the embodiment described above, it is possible to electrically connect the main body substrate 500 and the LED control substrate 501 without making the cable 520 connecting the main substrate 500 and the LED control substrate 501 longer than necessary. become. Furthermore, when the image forming unit 400 is pulled out from the image forming apparatus 100, the connector 522 of the cable 520 and the connector 530 of the LED control board 501 are separated and electrically disconnected. This eliminates the need for a space for accommodating the extra length of the flat cable, and furthermore, even if the imaging unit 400 moves, the cable 520 is not broken due to bending. In addition, since the excess length of the cable 520 is not required, the cable length can be shortened. As a result, it is possible to prevent erroneous reception due to attenuation of the waveform of the electrical signal, and eliminate the need for parts for countermeasures against radiation noise, which reduces the cost. up can be suppressed.

As described above, according to this embodiment, it is possible to shorten the length of the cable that connects the main substrate and the relay substrate.

100 Image forming apparatus 102 Photosensitive drum 106 Exposure head 400 Imaging unit 430 Side wall unit 501 Control board 522 Connector 530 Connector

Claims (5)

a device body having an opening formed on a side surface;
a drum cartridge having a rotatable photosensitive drum;
an optical print head having a light emitting element that emits light for exposing the photosensitive drum;
a first wall portion supporting one end side of the optical print head in the rotation axis direction of the photosensitive drum and a second wall portion supporting the other end side of the optical print head in the rotation axis direction, a support portion movable between a mounting position mounted on the main body and a drawer position drawn out from the mounting position through the opening;
a first connector provided on the device main body;
a second connector that is connected to the first connector when the support portion is positioned at the mounting position and is disconnected from the first connector when the support portion is positioned at the pulled-out position; wherein the light emission is based on a drive signal sent via the first connector when the support portion is positioned at the mounting position and the first connector and the second connector are connected to each other. a control board provided on either the first wall portion or the second wall portion for controlling the driving of the element ;
An image forming apparatus , wherein the first connector is provided on a body board provided in the apparatus body . a device main body having an opening formed on a side surface;
a drum cartridge having a rotatable photosensitive drum;
an optical print head having a light emitting element that emits light for exposing the photosensitive drum;
a first wall portion supporting one end side of the optical print head in the rotation axis direction of the photosensitive drum and a second wall portion supporting the other end side of the optical print head in the rotation axis direction, a support portion movable between a mounting position mounted on the main body and a drawer position drawn out from the mounting position through the opening;
a first connector provided on the device main body;
a second connector that is connected to the first connector when the support portion is positioned at the mounting position and is disconnected from the first connector when the support portion is positioned at the pulled-out position; wherein the light emission is based on a drive signal sent via the first connector when the support portion is positioned at the mounting position and the first connector and the second connector are connected to each other. a control board provided on a third wall portion that is continuous with ends of the first wall portion and the second wall portion on the upstream side in the direction in which the support portion is pulled out in order to control driving of the element; An image forming apparatus characterized by: 3. The image forming apparatus according to claim 2, wherein said first connector is provided on a body board provided in said apparatus body. 3. The image forming apparatus according to claim 1, wherein said first connector is connected to a main substrate provided in said apparatus main body via a flexible flat cable. 5. When the device main body with the supporting part attached is viewed from above in the vertical direction, the main body substrate is arranged on one side of the supporting part in the direction of the rotation axis. The image forming apparatus according to .

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