CN204964988U - Image forming device - Google Patents

Abstract

The utility model provides an image forming device capable of suppressing the temperature rise of the light source due to the air heated by the fixing part. In its frame, there are: an image forming part having a photoreceptor; a fixing part provided at a certain interval from the photoreceptor in a horizontal direction perpendicular to the direction of the rotation axis of the photoreceptor, and having a heating part; a light source; and a light guide part, has a receiving part for receiving light from the light source, and is configured to guide the light received by the receiving part to the surface of the photoreceptor; a fan, which discharges the air in the frame to the outside; and a shielding wall, where the light source is in the horizontal direction It is arranged between the photoreceptor and the fixing part, and is arranged on the inside of both ends of the image forming part opposite to the receiving part in the direction of the rotation axis. The shielding wall shields the fixing part side of the light source and is arranged at a position away from the light source. The part is disposed inside the two ends of the image forming part facing the light source in the direction of the rotation axis, and an air duct connected to the fan is formed between the light source and the shielding wall.

Description

image forming device

technical field

The technology disclosed in this specification relates to an image forming apparatus.

Background technique

Conventionally, there is known an electrophotographic image forming apparatus that charges a photosensitive drum to form a toner image, transfers the toner image to paper, and heat-fixes it by a fixing unit, thereby forming a toner image on the paper. Form the image. Such an image forming apparatus includes a static elimination device that removes the charge remaining on the photosensitive drum (for example, Patent Document 1). The static elimination device has: a light guide part, the light guide part is accommodated in the unit holding the photosensitive drum, and extends along the rotation axis direction of the photosensitive drum; and the light source is arranged at both ends of the unit in the rotation axis direction. outside, and opposite to one end of the light guide part in the direction of the rotation axis. The light source emits light from one end of the light guide portion, and irradiates the light entering from the end of the light guide portion onto the surface of the photosensitive drum, thereby destaticizing the photosensitive drum.

Patent Document 1: Japanese Unexamined Patent Publication No. 2011-227425

In an image forming apparatus, in order to reduce the size of the apparatus, a configuration may be considered in which the position of the light source is changed from an outer position to an inner position at both ends of the image forming unit such as a unit in the direction of the rotation axis. However, in this modified structure, the light source is arranged closer to the fixing unit than in the conventional structure, so that the temperature of the light source rises due to the air heated by the fixing unit, and the deterioration of the light source is promoted, which is likely to cause The problem of light source failure.

Utility model content

Problems to be solved by utility models

This specification discloses a technique capable of solving at least part of the above-mentioned problems.

means to solve the problem

(1) The image forming apparatus disclosed in this specification is an electrophotographic image forming apparatus comprising: a housing; a photoreceptor; a fixing part, which is provided in the frame at a certain interval from the photoreceptor in a horizontal direction perpendicular to the direction of the rotation axis of the photoreceptor, and has a heating part; a light source, The light source is provided in the frame; the light guide part is provided in the frame, has a receiving part for receiving light from the light source, and is configured to receive the light received from the receiving part guide to the surface of the photoreceptor; a fan that discharges the air in the frame to the outside; and a shielding wall that is provided in the frame, and the light source is provided in the horizontal direction at the Between the photoreceptor and the fixing unit, and on the inside of both ends of the image forming unit provided opposite to the receiving unit in the direction of the rotation axis, the shielding wall controls the fixing of the light source. part side is shielded and arranged at a position away from the light source, the receiving part is arranged inside the two ends of the image forming part facing the light source in the direction of the rotation axis, between the light source and the An air duct connected with the fan is formed between the shielding walls. In this image forming apparatus, the light source is provided between the photoreceptor and the fixing unit in the horizontal direction, and is provided inside both ends of the image forming unit in the direction of the rotation axis of the photoreceptor. The light guiding part has a receiving part for receiving light from a light source, and is configured to guide the light received from the receiving part to the surface of the photoreceptor. The receiving portion is located inside both ends of the image forming portion in the direction of the rotation axis. Therefore, the size of the image forming apparatus in the direction of the rotation axis can be reduced in comparison with a conventional structure in which the light sources are arranged outside both ends of the image forming portion in the direction of the rotation axis. In such an image forming apparatus, the light source can be arranged closer to the fixing unit than in the conventional configuration. However, since this image forming apparatus has a shielding wall that shields the light source from the fixing unit side, air heated by the fixing unit can be suppressed from reaching the light source compared to a case without the shielding wall. In addition, the light source and the shielding wall are separated from each other, and since an air passage connected to the fan is formed between the light source and the shielding wall, the air heated by the fixing unit does not stay around the light source due to air flowing in the air passage. Thus, the size of the device can be reduced, and the temperature rise of the light source due to the air heated by the fixing unit can be suppressed.

(2) In the image forming apparatus described above, the light source has an emission port from which light is emitted, and the image forming apparatus further includes a cover body that covers at least the portion of the light source other than the emission port. Partially housed and formed with a hole for opening the injection port, the cover body constitutes the shielding wall as a part of the cover body, and in the part of the cover body other than the shielding wall, a There is an inflow hole and an outflow hole, and the fan can also be arranged on the side of the cover body where the outflow hole is formed, through the inflow hole and the outflow hole, between the light source and the shielding wall An air duct connected to the fan is formed therebetween. According to such an image forming apparatus, since the cover body accommodates at least part of the light source other than the emission port, air heated by the fixing unit can be suppressed from reaching the light source compared to the case without the cover body. In addition, by forming the inflow hole and the outflow hole in the part of the cover body except the shielding wall, and the fan is provided on the side of the cover body on which the outflow hole is formed, there is a gap between the shielding wall constituting a part of the cover body and the light source. A ventilation channel connected to the fan is formed between them. Thereby, the temperature rise of the light source due to the air heated by the fixing unit can be suppressed.

(3) In the image forming apparatus described above, the inflow hole may be formed on the lower surface of the cover body, the outflow hole may be formed on the upper surface of the cover body, and the fan may be disposed on the lower surface of the cover body. above the cover. With this image forming apparatus, since the inflow hole, the outflow hole, and the fan are aligned and arranged along the vertical direction of the cover body, it is easier to form the image forming apparatus than if they are not arranged in a predetermined direction including the up and down direction of the cover body. The flow of air connected to the fan. In addition, since the fan is arranged above the cover body, an upward airflow is generated in the cover body. Therefore, compared with the case where a downdraft is generated inside the cover, the entry of toner and paper dust into the cover can be suppressed, and the reduction of static electricity removal performance due to contamination of the light source can be suppressed.

(4) In the image forming apparatus described above, the fan may be provided on the side surface of the housing at one of both ends of the image forming unit in the direction of the rotation axis, and the light guide unit may have a : a first light guide part, the first light guide part extends along the rotation axis direction and is arranged opposite to the photoreceptor; and a second light guide part, the second light guide part extends from the first light guide part One end portion of one end portion extends in a direction perpendicular to the direction of the rotation axis, and the top end portion in the extending direction becomes the receiving portion, and the light source and the receiving portion are provided at both ends of the image forming portion. There is said one end side of said fan. According to this image forming apparatus, the fan, the light source, and the receiving unit are provided at one of the two ends of the image forming unit, so that the flow of air connected to the fan can be easily formed. Compared with the case where the fan and the light source are provided on different end sides, it is easier to discharge the air near the light source to the outside by the fan. Thereby, the temperature rise of the light source due to the air heated by the fixing unit can be suppressed.

(5) In the image forming apparatus described above, the image forming apparatus may further include a guide member provided in the housing between the image forming unit and the fixing unit, and guide the sheet The material is guided from the side of the image forming part to the side of the fixing part, and a plurality of communication holes connected to the outside of the frame are provided on the guide member, and one communication hole among the plurality of communication holes is The cover body is provided on the guide member so as to be connected to the inflow hole. According to this image forming apparatus, a guide member for guiding the sheet from the image forming unit to the fixing unit is provided, and the guide member is provided with a plurality of communicating holes connected to the outside of the housing. Since one of the plurality of communicating holes provided in the guide member is connected to the inflow hole, air from the outside of the housing can easily flow into the cover, thereby suppressing an increase in the temperature of the light source.

(6) In the image forming apparatus described above, the second light guide may extend obliquely downward from the one end of the first light guide, and the obliquely downward is parallel to the rotation axis. In the direction perpendicular to the direction, the light source is opposite to the receiving part, and is arranged outside the conveying path of the sheet on the guide member, and the receiving part is extended to the second light guiding part. The end extending obliquely downward. Since the light source is provided obliquely below the photoreceptor, it is possible to configure an image forming apparatus that is smaller in the horizontal direction than when the light source is provided on the front side relative to the photoreceptor. In addition, since the light source is provided on the outside of the conveyance path of the sheet on the guide member, the sheet can be conveyed without obstructing the light source.

(7) In the image forming apparatus described above, the image forming apparatus may further include a partition wall whose lower end is positioned above the outflow hole, and whose upper end is positioned to the side of the fan. position, and the partition wall extends from the lower end to the upper end across both ends of the image forming portion in the direction of the rotation axis. According to the image forming apparatus, the partition wall can be used to form the air passage leading from the communication hole and the outflow hole to the fan.

(8) In the image forming apparatus described above, the image forming unit may be a process cartridge detachable from the housing, and the light guide unit may be provided on the process cartridge. With this image forming apparatus, since the light source is arranged on the inside of both ends of the process cartridge in the direction of the rotation axis of the photoreceptor, and the receiving portion is located on the inside of both ends of the process cartridge in the direction of the rotation axis of the photoreceptor, it can be compared with the conventional structure. The size of the image forming apparatus in the direction of the rotation axis is reduced.

(9) In the image forming apparatus described above, an opening area of the outflow hole may be smaller than an opening area of the inflow hole. According to this image forming apparatus, since the opening area of the outflow hole is smaller than the opening area of the inflow hole, the flow velocity of the air flowing out from the outflow hole is higher than the flow velocity of the air flowing into the inflow hole. Accordingly, it is possible to suppress the entry of toner and paper dust into the cover body through the outflow hole formed on the upper surface of the cover body.

(10) In the image forming apparatus described above, the image forming apparatus may further include: a substrate connected to the light source; and a transmission substrate that transmits an electrical signal to the substrate. The substrate is provided on the side of the fixing unit with respect to the light source, and a harness connecting the substrate and the transmission substrate is arranged through the inlet hole. According to this image forming apparatus, by arranging the wire harness through the inlet hole, the path through which the wire harness passes can be used as the air duct, and it is not necessary to separately provide a path through which the wire harness passes.

In addition, the technology disclosed in this specification can be realized in various forms, for example, it can be realized as a static elimination device, a light emitting device that irradiates light for static elimination, or the like.

Description of drawings

FIG. 1 is a cross-sectional view of a printer according to an embodiment.

2 is a perspective view of a photosensitive drum, a guide member, a light guide, and an EL.

3 is a schematic plan view of a photosensitive drum, a light guide unit, an EL, and a fixing unit.

4 is a perspective view of an EL, a support wall, a guide member, an air duct, and a fixing unit.

5 is a perspective view of a photosensitive drum, a supporting wall, a guide member, an air duct, and a fixing unit.

Fig. 6 is an enlarged sectional view of an EL and a guide member.

FIG. 7 is a diagram showing the positions of the substrate and the main substrate within the frame.

Fig. 8 is a perspective view of EL.

Fig. 9 is an enlarged perspective view of the periphery of a support portion of the guide member.

Symbol Description

2: Housing, 2B: Support wall, 2F: Rib, 6: Process cartridge, 7: Fixing unit, 8: EL, 9: Fan, 15: Guide member, 15D: Communication hole, 16: Support unit, 17: Support Hole, 18: Partition wall, 23: Photosensitive drum, 41: Light emitting part, 42: Board, 44: Ejection outlet, 45: Main board, 46: Harness, 51: Cover body, 52: Light emitting support part, 53: Shielding Wall, 55: outflow hole, 56: inflow hole, 61: light guide part, 62: first light guide part, 63: second light guide part, 66: receiving part, T: air duct.

detailed description

A printer 1 according to an embodiment will be described with reference to FIGS. 1 to 9 of the specification. The printer 1 is a monochrome laser printer that forms an image using monochrome (for example, black) toner. The printer 1 is an example of an electrophotographic image forming apparatus. In addition, in the following description, the right side of the paper in FIG. Side U.

The printer 1 has a housing 2 , and in the housing 2 , includes: a sheet supply unit 3 ; a scanner unit 5 ; a process cartridge 6 ; a fixing unit 7 ; a guide member 15 ;

The frame body 2 has a substantially rectangular parallelepiped shape as a whole, an opening 2C is formed on the front surface, and a front cover 2A is arranged to close the opening 2C. The lower end portion of the front cover 2A is supported by the frame body 2 so as to be rotatable around a rotation axis parallel to the left-right direction. Therefore, the front cover 2A can be displaced into two positions: a closed position for closing the opening 2C position (see FIG. 1 ); and an open position (not shown) that opens the opening 2C. In addition, a discharge port 10C is formed on the upper surface of the housing 2 , and a discharge tray 10B is formed in front of the housing 2 .

The sheet supply unit 3 is arranged at the lower portion of the housing 2 and has: a supply tray 10A; a pressing plate 11 ; a supply roller 12 ; a transport roller 13 ; The supply tray 10A can accommodate a plurality of sheets S, and is configured to be drawn out to the front side F of the printer 1 with respect to the housing 2 . The pressing plate 11 presses the sheet S accommodated in the supply tray 10A upward. The feed roller 12 is disposed above the feed tray 10A, and rotates by coming into contact with the sheet S pressed by the pressing plate 11 to feed the sheet S forward.

The conveyance roller 13 is arranged obliquely above the front side of the supply roller 12 , and conveys the sheet S sent out from the supply tray 10A to the registration roller 14 side. The registration rollers 14 are arranged obliquely above the rear side of the conveying rollers 13 , and correct the skew of the sheet S conveyed by the conveying rollers 13 in a U-shape, and convey the sheet S to the process cartridge 6 side. A solid line H in FIG. 1 indicates a conveyance path of the sheet S from the supply tray 10A to the discharge tray 10B.

The scanner unit 5 is arranged in the upper space inside the housing 2 , and emits the laser beam L1 to the charged portion of the photosensitive drum 23 described later by multi-face scanning to expose the charged portion of the photosensitive drum 23 . The process cartridge 6 is disposed between the sheet supply unit 3 and the scanner unit 5 . The process cartridge 6 is an example of an image forming unit, and has a frame 28, and inside the frame 28 are: a toner storage unit 20; a developing roller 22; a photosensitive drum 23; a charging unit 25; a transfer roller 24; and a cleaning roller 27. ; and the light guide 61 described later. The photosensitive drum 23 is an example of a photosensitive body.

The photosensitive drum 23 is cylindrical and has a photosensitive layer formed on its surface. The photosensitive drum 23 has a rotating shaft body 23A parallel to the left-right direction, and is rotatably supported by the frame 28 around the rotating shaft body 23A. Hereinafter, the direction of the rotating shaft body 23A may be referred to as the rotating shaft direction of the photosensitive drum 23 .

The charging unit 25 is disposed above the photosensitive drum 23 , and charges a charging position Y2 facing the charging unit 25 on the surface of the photosensitive drum 23 . The charged portion of the photosensitive drum 23 is exposed by the scanning section 5 , whereby an electrostatic latent image is formed on the surface of the photosensitive drum 23 . The developing roller 22 is disposed on the front side of the photosensitive drum 23 , and supplies the toner stored in the toner container 20 to the electrostatic latent image on the photosensitive drum 23 , thereby forming a toner image on the surface of the photosensitive drum 23 . .

The transfer roller 24 is disposed at a position facing the photosensitive drum 23 via the conveyance path of the sheet S. The sheet S conveyed by the registration roller 14 passes through a transfer position Y1 where the photosensitive drum 23 and the transfer roller 24 are opposed. The transfer roller 24 transfers the toner image on the photosensitive drum 23 onto the sheet S at the transfer position Y1 by static electricity. In addition, the cleaning roller 27 eliminates the toner, paper dust, etc. attached to the surface of the photosensitive drum 23 before being recharged by the charging unit 25 after the light guide unit 61 removes the static electricity.

The fixing unit 7 is provided at a constant interval from the photosensitive drum 23 in a direction perpendicular to the direction of the rotation axis of the photosensitive drum 23 . The direction perpendicular to the rotation axis direction of the photosensitive drum 23 is an example of the horizontal direction. Specifically, the fixing unit 7 is arranged behind the photosensitive drum 23, that is, on the downstream side of the photosensitive drum 23 in the transport path H, and the sheet S on which the toner image is transferred passes through the registration roller 14, the photosensitive drum 23, and the like. And it is conveyed from the photosensitive drum 23 to the side of the fixing unit 7 . The fixing section 7 has: a heating section 7A having a heater inside; and a pressure roller 7B disposed opposite to the heating section 7A, and the sheet S on which the toner image is transferred is heated by the heating section 7A and passed through the pressure roller. 7B conveys it, and thermally fixes the toner image on the sheet S. The sheet S to which the toner image is thermally fixed is discharged onto a discharge tray 10B by a discharge roller 30 .

The guide member 15 is provided between the process cartridge 6 and the fixing unit 7 in the front-rear direction of the printer 1 , and guides the sheet S from the process cartridge 6 side to the fixing unit 7 side. Specifically, as shown in FIG. 2 , the guide member 15 has a substantially flat plate shape as a whole. The left and right ends of the guide member 15 are disposed at approximately the same positions as the left and right ends of the photosensitive drum 23 in the direction of the rotation axis of the photosensitive drum 23 , or located outside the left and right ends of the photosensitive drum 23 .

A plurality of ribs 15C for guiding the sheet S are provided on the upper surface 15B of the guide member 15 , and the plurality of ribs 15C are arranged at intervals in the direction of the rotation axis of the photosensitive drum 23 . The upper end portion of each rib 15C is bent so as to become lower as it goes from the process cartridge 6 side to the fixing unit 7 side, and becomes higher in the middle. A plurality of communication holes 15D for ventilating the inside of the housing 2 are formed through the guide member 15 as will be described later. The plurality of communication holes 15D are formed at positions between the respective ribs 15C and at positions outside the ribs 15C at both left and right ends (see FIG. 6 ). Further, at one end (right end in FIG. 2 ) of the guide member 15 in the left-right direction, a support portion 16 for supporting an erasure laser (hereinafter referred to as “EL”) 8 to be described later is provided. The detailed structure of the support portion 16 will be described later.

The process cartridge 6 is provided detachably with respect to the housing 2 . By setting the front cover 2A to the open position, the process cartridge 6 can be taken in and out through the opening 2C of the housing 2 . Specifically, a pair of support walls 2B are provided inside the housing 2, and as shown in FIG. As shown in FIG. 5 , among the pair of support walls 2B, a rib 2F is formed on the support wall 2B disposed on the right side, and the rib 2F is used to separate the right end portion of the rotating shaft body 23A of the photosensitive drum 23 from the side of the opening 2C. Guided to the guide member 15 side. Similarly, although not shown, a rib 2F is formed on the support wall 2B arranged on the left side for guiding the left end portion of the rotating shaft body 23A of the photosensitive drum 23 from the opening 2C side to the guide member 15 . side.

To install the process cartridge 6 in the frame body 2, as shown in FIG. Into the inner side of the frame body 2.

The printer 1 further includes a fan 9 and a partition wall 18 capable of exhausting air heated by the fixing unit 7 to the outside of the housing 2 . Specifically, as shown in FIG. 1 , fan 9 is provided on side surface 2D of support wall 2B located on the right side, rotates, and discharges the air in housing 2 to the outside. The side surface 2D is an example of a side surface of the housing on one side of both ends of the image forming unit. The fan 9 is disposed on the upper side of the communication hole 15D which is the rightmost communication hole 15D among the plurality of communication holes 15D formed in the guide member 15 .

As shown in FIG. 4 , the partition wall 18 has a flat plate-like shape extending in the left-right direction as a whole. In the partition wall 18 , an air duct is formed between an unillustrated wall disposed on the front side of the partition wall 18 with a gap therebetween (see FIG. 1 ). The lower end of the partition wall 18 is arranged above the plurality of communication holes 15D of the guide member 15, and the upper end of the partition wall 18 is arranged at the position to the fan 9, and extends over the entire length of the process cartridge 6 and the fixing unit 7 in the left-right direction. Extends from bottom to top. Thus, the partition wall 18 partitions the space between the process cartridge 6 and the fixing unit 7 (see FIG. 1 ).

Between the guide member 15 and the supply tray 10A, a structure 19 such as an inversion guide for double-sided printing is arranged, and a hole 19A is formed through the structure 19 . In addition, a gap 2G is ensured between the rear end of the supply tray 10A and the rear surface of the housing 2 . With the above structure, as shown by the dotted line arrow in FIG. 1 , in the frame body 2, there are formed an air duct formed from the gap 2G through the hole 19A of the structure 19, the communication hole 15D formed in the guide member 15, and the partition wall 18. The air duct T connected to the outside with the fan 9 is used to discharge the air heated by the fixing unit 7 to the outside of the housing 2 .

The printer 1 further includes a light guide portion 61 and an EL 8 , and after the toner image is transferred, the charge remaining on the surface of the photosensitive drum 23 is removed, that is, static is eliminated.

The light guide unit 61 has a receiving unit 66 for receiving light from the EL 8 , and guides the light received by the receiving unit 66 to the surface of the photosensitive drum 23 . As described above, the light guide portion 61 is provided on the process cartridge 6 (see FIG. 1 ). The light guide 61 is made of, for example, a colorless and transparent acrylic resin, and has a first light guide 62 and a second light guide 63 . Both the first light guide part 62 and the second light guide part 63 are formed in a columnar shape, and one ends of the two are connected to each other so as to be substantially perpendicular to each other, whereby the light guide part 61 has a substantially L-shape as a whole. Here, "approximately orthogonal" is not limited to 90 degrees, but also includes cases where the angle formed by the axial direction of the first light guide part 62 and the axial direction of the second light guide part 63 is, for example, 80° to 100°. within the range of angles.

The first light guide portion 62 extends in the direction of the rotation axis of the photosensitive drum 23 and is arranged to face the photosensitive drum 23 . Specifically, as shown in FIG. 1 , the first light guide portion 62 is arranged between the photosensitive drum 23 and the fixing portion 7 , on the surface of the photosensitive drum 23 , from the transfer position in the rotation direction X of the photosensitive drum 23 . The positions between Y1 and the charging position Y2 are relative. The first light guide portion 62 is formed in a substantially D-shaped cross section, the front surface 64 facing the photosensitive drum 23 has an arcuate cross section, and the rear surface 65 has a smooth surface. The light received by the receiving portion 66 and guided by the second light guiding portion 63 passes through the rear surface 65 of the first light guiding portion 62 , is reflected toward the front surface 64 side, and is irradiated on the surface of the photosensitive drum 23 .

As shown in FIG. 3 , the length in the left-right direction of the first light guide portion 62 is slightly shorter than that of the photosensitive drum 23 , and both ends of the first light guide portion 62 are located in the photosensitive drum 23 in the direction of the rotation axis of the photosensitive drum 23 . The outer sides of both ends of the transfer region R1. The transfer area R1 is an area of the photosensitive drum 23 through which the sheet S of the largest size capable of image formation by the printer 1 passes, and is an area for forming an image on the sheet S. As shown in FIG. In the photosensitive drum 23 , the non-transfer regions R2 located on the left and right sides of the transfer region R1 are regions where the sheet S does not pass and are not used to form an image on the sheet S.

As shown in FIG. 2 , the second light guide part 63 extends obliquely downward backward from the right end part of the first light guide part 62 , and the tip part in the extending direction becomes the receiving part 66 . In addition, as shown in FIG. 3, the receiving portion 66 is arranged inside the both ends 28A, 28B of the frame 28 of the process cartridge 6 in the direction of the rotation axis of the photosensitive drum 23, and is arranged at the right end 28A of these two ends 28A, 28B. side. More specifically, the second light guide portion 63 is disposed opposite to the light emitting portion 41 of the EL8 described later.

The receiving part 66 functions as an incident surface that receives light from the EL8. The light received by the receiving part 66 is reflected to the rotation axis direction of the photosensitive drum 23 by the reflection surface 67 of the connection part of the first light guide part 62 and the second light guide part 63, and is guided to the second light guide part. Section 63.

The EL8 is provided between the photosensitive drum 23 and the fixing unit 7 in the front-rear direction, and is provided inwardly of both ends of the process cartridge 6 in the direction of the rotation axis of the photosensitive drum 23 , and faces the receiving portion 66 of the light guide 61 . In other words, the EL8 is disposed between the photosensitive drum 23 and the fixing unit 7 when viewed from the direction (vertical direction) perpendicular to the direction (horizontal direction) of the arrangement direction of the photosensitive drum 23 and the fixing unit 7 and the direction of the rotation axis of the photosensitive drum 23 . between, and disposed inside the two ends of the process cartridge 6 . Specifically, the EL8 is disposed at a position obliquely below the second light guide portion 63 of the light guide portion 61 (see FIG. 2 ), and emits light toward the receiving portion 66 located obliquely above the front side. As shown in FIG. 6 showing the A-A cross section in FIG. 2 , the EL8 has a light emitting unit 41 , a substrate 42 and a resin cover body 51 . The light emitting unit 41 is an example of a light source.

The light emitting unit 41 has: an LED (Light Emitting Diode) element 43 ; and a lens member 47 . The LED element 43 is mounted on the upper surface 42A of the substrate 42 so that the receiving portion 66 of the light guide portion 61 is positioned on the optical axis Z of the LED element 43 . The lens member 47 has a cylindrical shape as a whole, and an output lens 47A is provided on the distal end side in the direction of the optical axis Z, and the base end side is fixed to the substrate 42 . The emission lens 47A condenses the light emitted from the LED element 43 to enter the receiving portion 66 of the light guide portion 61 . In addition, the tip of the lens member 47 on the side of the emission lens 47A is the emission port 44 .

The substrate 42 is provided on the side of the fixing unit 7 with respect to the light emitting unit 41 . Specifically, the substrate 42 is located on the rear side of the light emitting unit 41 , and the upper surface 42A of the substrate 42 is arranged in an inclined posture facing obliquely upward to the front side. The substrate 42 is electrically connected to the LED element 43 . In addition, as shown in FIG. 7 , the substrate 42 is electrically connected to the main substrate 45 arranged on the left side in the housing 2 by a wire harness 46 . The substrate 42 receives an electrical signal for turning on the LED element 43 from the main substrate 45 , and turns on the LED element 43 based on the electric signal. The main substrate 45 is an example of a transfer substrate.

The cover body 51 accommodates at least a portion of the light emitting unit 41 excluding the emission port 44 , and is formed with a hole 54 that opens the emission port 44 of the light emitting unit 41 . That is, in the light emitting unit 41 , the portion of the emission port 44 is exposed to the outside through the hole 54 , and the portion other than the emission port 44 is covered by the cover body 51 .

Specifically, the cover body 51 has a substantially rectangular parallelepiped shape as a whole, and has a light emitting support portion 52 and a shielding wall 53 . The light emitting support wall 52 is an example of a portion of the cover body other than the shielding wall. The light-emitting support portion 52 is made of, for example, ABS resin, has a box-like shape with an open rear end, and has the above-mentioned hole 54 penetratingly formed in the upper part of the front surface. Also, as shown in FIG. 8 , an outflow hole 55 is formed on the upper surface 52A of the light emitting support portion 52 , and an inflow hole 56 is formed on the lower surface 52B of the light emitting support portion 52 . In addition, as shown in FIG. 8 , the opening area of the outflow hole 55 is formed smaller than the opening area of the inflow hole 56 .

The shielding portion 53 shields the light emitting portion 41 from the fixing portion 7 side, and is arranged at a position away from the light emitting portion 41 and the substrate 42 on the fixing portion 7 side. Specifically, the shielding wall 53 is disposed so as to cover the rear end side of the light emitting support portion 52 . In other words, the shielding wall 53 is disposed between the fixing unit 7 and the light emitting unit 41 so as to hide the light emitting unit 41 behind when viewed from the side of the fixing unit 7 . The shielding wall 53 is made of, for example, polycarbonate resin having higher heat resistance than ABS resin, and has higher heat resistance than the light emitting support portion 52 . In addition, the shielding wall 53 is provided with an insertion portion 57 inserted into the support hole 17 provided in the support portion 16 of the guide member 15 (see FIGS. 6 and 8 ).

The EL8 is arranged so as to be located on the air duct T for exhausting the air heated by the fixing unit 7 to the outside of the housing 2 . Specifically, a support portion 16 (see FIG. 2 ) for supporting an EL8 described later is provided in a portion of the guide member 15 where the communicating hole 15D located at the right end is formed. Therefore, the EL8 is arranged outside the transfer region R1 of the photosensitive drum 23 in the left-right direction.

As shown in FIG. 9 , the support portion 16 has a support hole 17 and a support surface 15A located on the front side of the support hole 17 . The insertion portion 57 of the shielding wall 53 is inserted into the support hole 17, whereby the EL8 is fixed to the guide member 15, and the lower surface 52B of the light emitting support portion 52 is supported on the support surface 15A. This support surface 15A penetrates through a communication hole 15D formed at the right end.

As shown in FIG. 6 , when the EL8 is fixed to the support portion 16 , the communication hole 15D at the right end communicates with the inflow hole 56 of the cover body 51 . In this way, in the cover body 51 , air passages T are formed between the light emitting unit 41 and the shielding wall 53 disposed apart from each other in the front-rear direction of the printer 1 , and between the substrate 42 and the shielding wall 53 . Thus, the gap 2G of the frame body 2 passes through the hole 19A of the structure 19, the communication hole 15D formed at the right end of the guide member 15, the inflow hole 56, the outflow hole 55, the air duct formed by the partition wall 18, and the fan. 9, and the ventilation channel T connected with the outside.

Since such an air passage T is formed, when the fan 9 is driven, as shown in FIG. and the outflow hole 55 to generate an updraft in the cover body 51 .

As shown in FIG. 7 , the wiring harness 46 connecting the substrate 42 and the main substrate 45 is arranged through the communication hole 15D at the right end of the guide member 15 , the inflow hole 56 of the cover body 51 , and the hollow 2H expanding toward the lower side D of the guide member 15 . . The communication hole 15D and the inflow hole 56 also serve as a hole for arranging the wire harness 46 .

As described above, in the printer 1 of the present embodiment, the light emitting unit 41 is provided between the photosensitive drum 23 and the fixing unit 7 in the horizontal direction, and is provided on both sides of the frame 28 of the process cartridge 6 in the direction of the rotation axis of the photoconductor. Inboard of ends 28A, 28B. The light guide portion 61 has a receiving portion 66 for receiving light from the light emitting portion 41 , and guides the light received by the receiving portion 66 to the surface of the photosensitive drum 23 . The receiving portion 66 is located inside the both ends 28A, 28B of the frame 28 of the process cartridge 6 in the direction of the rotation axis. Therefore, as shown by the dotted line in FIG. 3, compared with the conventional structure in which the light-emitting portion 41 is disposed outside the two ends 28A, 28B of the frame 28 of the process cartridge 6 in the direction of the rotation axis, the printer 1 in the direction of the rotation axis can be reduced. The size is made small.

On the other hand, in this type of printer 1 , the light emitting unit 41 is arranged closer to the fixing unit 7 than in the conventional configuration. The printer 1 according to the present embodiment has the shielding wall 53 that shields the light emitting unit 41 from the fixing unit 7 side. Therefore, air heated by the fixing unit 7 can be suppressed from reaching the light emitting unit 41 compared to the case without the shielding wall 53 . In addition, since the light emitting unit 41 and the shielding wall 53 are arranged apart from each other, and the air duct T connected to the fan is formed between the light emitting unit 41 and the shielding wall 53, the air heated by the fixing unit 7 will not be blown by the air duct T. The flow of the air flowing in the air stays around the light emitting part 41 . Accordingly, the size of the printer 1 can be reduced, and an increase in the temperature of the light source due to the air heated by the fixing unit 7 can be suppressed.

In the printer 1 of the present embodiment, since there is the cover body 51 that accommodates at least the portion of the light emitting unit 41 other than the hole 54, compared with the case without the cover body 51, the heating by the fixing unit 7 can be suppressed. A phenomenon in which air reaches the light emitting unit 41 . In addition, an inflow hole 56 and an outflow hole 55 are respectively formed on the light emitting support portion 52 except for the shielding wall 53 of the cover body 51 , and a fan is provided on the upper side U of the cover body 51 where the outflow hole 55 is formed. 9. As a result, an air duct T connected to the fan 9 is formed between the shielding wall 53 constituting a part of the cover body 51 and the light emitting portion 41 . Thereby, the temperature rise of the light emitting part 41 by the air heated by the fixing part 7 can be suppressed.

In the printer 1 of the present embodiment, since the inflow hole 56, the outflow hole 55, and the fan 9 are arranged along the vertical direction of the cover body 51, they are not arranged in a predetermined direction including the vertical direction of the cover body. Compared with these cases, it is easier to form the air flow connected to the fan 9 . In addition, since the fan 9 is arranged above the cover body 51 , an updraft is generated in the cover body 51 . Therefore, compared with the case where a downdraft occurs in the cover body 51 , entry of toner and paper dust into the cover body 51 can be suppressed, and a reduction in static electricity removal capability due to contamination of the light source 41 can be suppressed.

In the printer 1 of the present embodiment, the fan 9 , the light emitting unit 41 and the receiving unit 66 are provided on the common end side of both ends of the process cartridge 6 , so that the air flow connected to the fan 9 can be easily formed. Compared with the case where the fan 9 and the light emitting unit 41 are provided on different end sides, it is easier to discharge the air near the light emitting unit 41 to the outside using the fan 9 . Thereby, the temperature rise of the light emitting part 41 by the air heated by the fixing part 7 can be suppressed.

In the printer 1 of the present embodiment, a guide member 15 for guiding the sheet S from the process cartridge 6 to the fixing unit 7 is provided, and a plurality of communication channels connected to the outside of the housing 2 are provided on the guide member 15 . Hole 15D. Since one of the plurality of communication holes 15D provided in the guide member 15D is connected to the inflow hole 56, the air from the outside of the housing 2 easily flows into the cover body 51, thereby suppressing the temperature of the light emitting portion 41. rise.

In the printer 1 of the present embodiment, since the light-emitting unit 41 is arranged obliquely below the photosensitive drum 23, compared with the case where the light-emitting unit 41 is arranged on the front side of the photosensitive drum 23, it can be configured to be smaller in the horizontal direction. 1 of the printers. In addition, since the light emitting unit 41 is provided outside the conveyance path of the sheet S on the guide member 15 , the sheet S can be conveyed without obstructing the light emitting unit 41 .

In the printer 1 of the present embodiment, since the lower end of the partition wall 18 is disposed above the plurality of communication holes 15D of the guide member 15, and the upper end of the partition wall 18 is disposed at the position to the fan 9, the use of the partition wall The air duct formed by 18 can form the ventilation channel T connected to the fan 9 from the communication hole 15D and the outflow hole 55 .

In the printer 1 of this embodiment, since the light-emitting part 41 is provided inside the both ends 28A, 28B of the frame 28 of the process cartridge 6 in the direction of the rotation axis of the photosensitive drum 23 , the receiving part 66 is positioned in the direction of the rotation axis of the photosensitive drum 23 . Since the upper side is located inside the both ends 28A, 28B of the frame 28 of the process cartridge 6, the size of the printer 1 in the direction of the rotation axis can be reduced compared with the conventional structure.

In the printer 1 of the present embodiment, since the opening area of the outflow hole 55 is smaller than that of the inflow hole 56 , the velocity of the air flowing out from the outflow hole 55 is increased compared to the velocity of the air flowing into the inflow hole 56 . Accordingly, it is possible to suppress the entry of toner and paper dust into the cover body through the outflow hole 55 formed on the upper surface of the cover body 51 .

In the printer 1 of the present embodiment, by disposing the wire harness 46 connecting the substrate 42 and the main substrate 45 through the inflow hole 56, the path through which the wire harness 46 passes is used as an air duct, and there is no need to separately provide a path through which the wire harness 46 passes.

The technology disclosed in this specification is not limited to the embodiments described above and based on the drawings, but also includes, for example, the following various forms.

In the above-mentioned embodiment, the example in which the scanning unit 5 emits the laser light L1 to the charging portion of the photosensitive drum 23 by the multi-face scanning method was illustrated, but the present invention is not limited thereto. For example, the scanning unit 5 may be an LED type including a plurality of LED elements arranged in the direction of the rotation axis of the photosensitive drum 23 .

In the above-mentioned embodiment, the example in which the process cartridge 6 has the transfer roller 24 was illustrated, but it is not limited to this, The transfer roller 24 may be rotatably supported by the housing 2. As shown in FIG. In addition, the process cartridge 6 detachably attached to the frame body 2 may be attached to the frame body 2 so as to face the photosensitive drum 23 in the process cartridge 6 .

In the above-mentioned embodiment, the example in which the process cartridge 6 has the light guide part 61 was illustrated, but it is not limited to this, The light guide part 61 may be supported by the housing|casing 2. As shown in FIG. Thereby, the relative position of the light emitting part 41 and the light guide part 61 changes by attachment and detachment of the process cartridge 6, and it can suppress that the static elimination ability falls.

In the above-mentioned embodiment, the example in which the inflow hole 56 and the outflow hole 55 are respectively formed on the lower surface 52B and the upper surface 52A of the light-emitting support part 52 is illustrated, but it may be arranged, for example, in a case where the fan 9 is aligned with the EL8 in the rotation axis direction. In the case of arrangement, the inflow hole 56 and the outflow hole 55 are respectively formed on the right surface and the left surface of the light emitting support part 52 . On the other hand, since the shielding portion 53 shields the portion of the light emitting portion 41 on the side of the fixing portion 7 , the inflow hole 56 and the outflow hole 55 are not formed in the shielding portion 53 .

In the above-mentioned embodiment, an example was illustrated in which the hole of the frame body 2 through which the air duct T passes is the gap 2G provided between the rear end of the supply tray 10A and the rear surface of the frame body 2, but the present invention is not limited thereto. , any hole formed in the frame body 2 can also be utilized.

In the above-mentioned embodiment, the example in which the part other than the emission port 44 of the light emitting part 41 is accommodated in the cover body 51 was illustrated, but it is not limited to this. For example, the entire light emitting unit 41 including the emission port 44 may be accommodated in the cover body 51 . In this case, as long as the lens is arranged in the hole 54 formed in the light emitting supporting part 52, and the emission port 44 of the light emitting part 41 can be visually confirmed through the lens, the light emitting part 41 can be used to eliminate the static electricity on the photosensitive drum 23. The light is irradiated to the light guide part 61 .

In addition, the light emitting unit 41 may not be covered by the light emitting support unit 52 on the front side F of the printer 1 , in the left-right direction, and in the vertical direction. In this case, since the portion of the light emitting unit 41 on the side of the fixing unit 7 is shielded by the shielding wall 53 , heat from the fixing unit 7 can be suppressed from reaching the light emitting unit 41 compared to the case without the shielding wall 53 .

In this case, the air flows in or out from the space between the light emitting unit 41 and the shielding wall 53 or between the substrate 42 and the shielding wall 53 from, for example, the left-right direction and the up-down direction of the printer 1, so it is not necessary to form an inflow hole. 56 and outflow hole 55.

In the above-mentioned embodiment, the example in which the first light guide part 62 and the second light guide part 63 are connected orthogonally in the light guide part 61 was illustrated, but it is not limited to this. For example, the receiving portion 66 may be arranged inside the both ends 28A, 28B of the frame 28 of the process cartridge 6 in the direction of the rotation axis of the photosensitive drum 23, and the first light guiding portion 62 and the second light guiding portion 63 may be connected to each other. into a cross.

Claims (10)

1. An image forming device, which is an electrophotographic image forming device, is characterized in that it has: framework; an image forming unit provided in the housing and having a photoreceptor that rotates around a rotation axis; a fixing section provided in the frame at a certain interval from the photosensitive body in a horizontal direction perpendicular to the direction of the rotation axis of the photosensitive body, and having a heating section; a light source, the light source is arranged in the frame; a light guide part, which is provided in the housing, has a receiving part for receiving light from the light source, and is configured to guide the light received from the receiving part to the surface of the photoreceptor; a fan that exhausts the air inside the frame to the outside; and a shielding wall, the shielding wall is arranged in the frame, The light source is provided between the photoreceptor and the fixing unit in the horizontal direction, and is provided inwardly of both ends of the image forming unit so as to face the receiving unit in the rotation axis direction, The shielding wall shields the fixing unit side of the light source and is arranged at a position away from the light source, The receiving portion is disposed on the inner side of both ends of the image forming portion so as to face the light source in the direction of the rotation axis, An air duct connected to the fan is formed between the light source and the shielding wall. 2. The image forming apparatus according to claim 1, wherein: The light source has an emission port for emitting light, The image forming apparatus further has a cover body, The cover accommodates at least a portion of the light source other than the injection port, and is formed with a hole opening the injection port, The cover body constitutes the shielding wall as a part of the cover body, and an inflow hole and an outflow hole are respectively formed in a part of the cover body except the shielding wall, The fan is arranged on the side of the cover body on which the outflow hole is formed, An air duct connected to the fan is formed between the light source and the shielding wall via the inflow hole and the outflow hole. 3. The image forming apparatus according to claim 2, wherein: the inflow hole is formed on the lower surface of the cover body, the outflow hole is formed on the upper surface of the cover body, The fan is arranged above the cover body. 4. The image forming apparatus according to claim 3, wherein: The fan is provided on a side surface of a housing at one of both ends of the image forming unit in the direction of the rotation axis, The light guide has: a first light guide part, the first light guide part extends along the direction of the rotation axis and is arranged opposite to the photoreceptor; and a second light guide part, the second light guide part extends from one end part of the first light guide part in a direction perpendicular to the direction of the rotation axis, and a tip part in the extending direction becomes the receiving part, The light source and the receiving section are provided on the one end side where the fan is provided, among both ends of the image forming section. 5. The image forming apparatus according to claim 4, wherein: The image forming apparatus further includes a guide member provided in the housing between the image forming unit and the fixing unit, and guiding the sheet from the image forming unit side to the fixing unit. side, A plurality of communication holes connected to the outside of the frame are provided on the guide member, The cover body is provided on the guide member such that one of the plurality of communication holes is connected to the inflow hole. 6. The image forming apparatus according to claim 5, wherein: The second light guide part extends obliquely downward from the one end of the first light guide part, and the oblique downward direction is a direction perpendicular to the rotation axis direction, The light source is opposite to the receiving part, and is arranged on the outside of the conveying path of the sheet on the guide member, and the receiving part is an end part of the second light guide part extending obliquely downward. 7. The image forming apparatus according to claim 6, wherein: The image forming apparatus further has a partition wall whose lower end is located above the outflow hole, whose upper end is located at a position up to the fan, and extends over the rotation axis direction. Both ends of the image forming part extend from the lower end to the upper end. 8. The image forming apparatus according to claim 4, wherein: The image forming unit is a process cartridge detachable from the housing, The light guide part is provided on the process cartridge. 9. The image forming apparatus according to claim 4, wherein: The opening area of the outflow hole is smaller than the opening area of the inflow hole. 10. The image forming apparatus according to claim 4, wherein: The image forming apparatus further has: a substrate connected to the light source; and a transfer substrate that transfers electrical signals to said substrate, The substrate is provided on the side of the fixing unit with respect to the light source, A wire harness connecting the substrate and the transmission substrate is arranged through the inlet hole.