JP2018138352A - Exposure apparatus and image formation apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an exposure apparatus which can improve decomposition performance while securing sealability to prevent mixing of foreign matters, and an image formation apparatus.SOLUTION: An exposure apparatus comprises: a substrate 6 on which light emitters 5 are arranged in a specified direction; a holding member 1 which holds the substrate 6; a substrate pressing member 8 including a fitting part 8b of an elastic body which is fitted into the holding member 1, and a first aperture 8c which is arranged facing the fitting part 8b; and a sheet member 9 which is arranged between the substrate 6 and the substrate pressing member 8. A sealant is arranged between the holding member 1 and the substrate pressing member 8, and the sheet member 9 is exposed from the first aperture 8c.SELECTED DRAWING: Figure 2

Description

  The present invention relates to an exposure apparatus and an image forming apparatus.

  For example, an exposure apparatus used in an image forming apparatus such as a printer, a copying machine, a facsimile machine, or a multi-function machine exposes a charged photosensitive drum by irradiating light corresponding to image information, and forms an electrostatic latent image. To form.

  A conventional exposure apparatus, for example, a substrate on which an LED (Light Emitting Diode) array is mounted, a holder that holds the substrate, and a holder that is opposed to the LED array and supported by the holder, and converges light emitted from the LED array. A rod lens array and a base for pressing the substrate against the holder are provided. Then, the light emitted from the LED array mounted on the substrate passes through the rod lens array, is converged, and is exposed on the surface of the photosensitive drum disposed at the imaging position of the rod lens array. An electrostatic latent image is formed (see, for example, Patent Document 1).

JP 2009-73041 A

  In the conventional exposure apparatus, a sealing material is filled in the slit in the clamp part of the base in order to prevent the intrusion of foreign matter, but since the sealing material wraps around to the back side of the base, the slit has a narrow opening, There is a problem that it takes time to remove the cured sealing material, and it is difficult to disassemble the LED head.

  The present invention has been made in view of such a situation, and an object of the present invention is to provide an exposure apparatus and an image capable of improving the disassembly performance while ensuring the sealing performance for preventing foreign matter from being mixed. A forming apparatus is provided.

  In order to solve the above-described problems, an exposure apparatus according to the present invention includes a substrate on which a light emitting element is disposed in a predetermined direction, a holding member that holds the substrate, and an elastic body that fits the holding member. And a sheet holding member disposed between the substrate and the substrate pressing member, the holding member having a first opening portion disposed at a position facing the fitting portion and the first opening. A sealant is disposed between the first opening and the substrate pressing member, and the sheet member is formed to be exposed from the first opening.

  The image forming apparatus according to the present invention includes a substrate on which a light emitting element is arranged in a predetermined direction, a holding member that holds the substrate, a fitting portion of an elastic body that fits the holding member, and the fitting A substrate pressing member having a first opening disposed at a position facing the portion, and a sheet member disposed between the substrate and the substrate pressing member, the holding member and the substrate pressing member A sealant is disposed between the exposure device and the exposure device formed so that the sheet member is exposed from the first opening, and the electrostatic latent image formed by the exposure device is developed. And an image forming unit for forming a developer image.

  According to the present invention, it is possible to provide an exposure apparatus and an image forming apparatus capable of improving the disassembling performance while ensuring sealing performance for preventing foreign matter from being mixed.

1 is a schematic configuration diagram illustrating a configuration of a printer according to an embodiment. It is a disassembled perspective cutaway view of the LED head concerning this embodiment. It is a cross-sectional view at the time of assembling the LED head of A part in FIG. It is a cross-sectional view at the time of assembling the LED head of the B part in FIG. It is a longitudinal cross-sectional exploded view of an LED head. It is explanatory drawing which expanded the clamp part vicinity in a base, in describing the positional relationship of a base and a sheet | seat. It is the longitudinal cross-sectional view which expanded the fitting hole vicinity of the holder at the time of assembling an LED head.

  Embodiments of the present invention will be described below with reference to the drawings. In addition, this invention is not limited to the following description, In the range which does not deviate from the summary of this invention, it can change suitably.

  First, a printer as an image forming apparatus according to the present invention will be described. The printer described in this embodiment is a color electrophotographic image forming apparatus including four image forming units and capable of forming a color image. Image data input using a developer (for example, toner). Can be formed on a sheet as a recording medium. The configuration of the printer 11 having such a function will be described with reference to the schematic configuration diagram of FIG.

  The printer 11 forms an image along a sheet conveyance path formed in a substantially S-shape starting from the sheet storage cassette 21, passing through the registration rollers 22, the conveyance belt 23, and the fixing device 24, and ending at the discharge stacker 25. Units 12Bk, 12Y, 12M, and 12C are provided.

  The sheet storage cassette 21 stores sheets as recording media in a stacked state, and is detachably attached to the lower part of the printer 11. The hopping roller 26 provided on the upper part of the paper storage cassette 21 takes out the paper stored in the paper storage cassette 21 one by one from the uppermost part and feeds it out to the paper transport path. A paper color measuring unit 27 that detects the color of the paper stored in the paper storage cassette 21 is provided immediately above the paper storage cassette 21. By the way, as the paper according to the present embodiment, OHP paper, envelopes, copy paper, special paper, and the like can be used in addition to plain paper.

  The registration roller 22 corrects the skew of the sheet fed from the hopping roller 26 and conveys the sheet to the conveyance belt 23.

  The conveyance belt 23 is an endless belt member that electrostatically attracts and conveys a sheet in the direction of arrow e in the figure, and includes a drive roller 23a that rotates by a driving force transmitted from a drive unit (not shown), and the drive roller 23a. And a tension roller 23b provided in a pair.

  The fixing device 24 is provided on the downstream side of the sheet conveyance path after the image forming units 12Bk, 12Y, 12M, and 12C, and includes a heat roller 24a, a backup roller 24b, a thermistor (not shown), and the like. For example, the heat roller 24a is formed by covering a hollow cylindrical cored bar made of aluminum or the like with a heat-resistant elastic layer of silicone rubber and coating a PFA (tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer) tube thereon. Is formed by. In the core bar, for example, a heater such as a halogen lamp is provided. The backup roller 24b has a structure in which, for example, a core metal made of aluminum or the like is coated with a heat-resistant elastic layer of silicone rubber and PFA is coated thereon, and is arranged so that a pressure contact portion is formed between the backup roller 24b and the heat roller. It is installed. The thermistor is means for detecting the surface temperature of the heat roller 24a, and is provided in the vicinity of the heat roller 24a in a non-contact manner. The surface temperature of the heat roller 24a is maintained at a predetermined temperature by controlling the heater based on the detection result of the surface temperature of the heat roller 24a detected by the thermistor. The sheet on which the developer image formed in the image forming units 12Bk, 12Y, 12M, and 12C is transferred passes through a pressure contact portion formed by the heat roller 24a and the backup roller 24b maintained at a predetermined temperature. Heat and pressure are applied to the developer on the paper, the developer melts, and the developer image is fixed.

  The discharge stacker 25 is formed using the outer casing of the printer 11 and stacks sheets that have passed through the fixing device 24 and discharged to the outside of the apparatus.

  As described above, the printer 11 according to the present embodiment employs a color electrophotographic method, and each development of black (K), yellow (Y), magenta (M), and cyan (C) is performed inside the printer 11. Image forming units 12Bk, 12Y, 70M, and 70C corresponding to the agent colors are provided. The image forming units 12Bk, 12Y, 12M, and 12C have different configurations except for the developer that is accommodated, and the other configurations can be the same.

  Each of the image forming units 12Bk, 12Y, 12M, and 12C includes an image carrier (for example, a photosensitive drum) 13Bk, 13Y, 13M, and 13C that carries an electrostatic latent image, and an image carrier 13Bk, 13Y, 13M, and 13C surface. A charger (for example, a charging roller) 14Bk, 14Y, 14M, 14C for uniformly and uniformly charging a developer (not shown in the electrostatic latent image formed on the surface of the image carrier 13Bk, 13Y, 13M, 13C) Are attached to each other to form a developer image of each color as a visible image (for example, a developing roller as a developer carrier) 16Bk, 16Y, 16M, 16C, and the developers 16Bk, 16Y, 16M, 16C. Developer supply rollers 18Bk, 18Y, 18M, and 18C as developer supply members that are in pressure contact with each other and supply the developer to the developing devices 16Bk, 16Y, 16M, and 16C; Image agent supply roller 18Bk, comprises 18Y, 18M, 18 developer supplying developer cartridge 20Bk, 20Y, 20M, and 20C.

  Each of the image carriers 13Bk, 13Y, 13M, and 13C includes a conductive support and a photoconductive layer. For example, a charge generation layer as a photoconductive layer, a charge generating layer as a photoconductive layer, and a charge on a metal shaft such as aluminum as a conductive support. It is an organic photoreceptor constituted by sequentially laminating a transport layer. Further, the image carriers 13Bk, 13Y, 13M, and 13C form an electrostatic latent image based on the light emitted from the LED heads 15Bk, 15Y, 15M, and 15C as an exposure apparatus described later while rotating in a predetermined direction. .

  The chargers 14Bk, 14Y, 14M, and 14C are made of, for example, a metal shaft such as stainless steel and a semiconductive epichlorohydrin rubber. The chargers 14Bk, 14Y, 14M, and 14C are in contact with the image carriers 13Bk, 13Y, 13M, and 13C with a predetermined pressure, and are based on a charging bias applied from a high-voltage power source (not shown). The surfaces of 13Bk, 13Y, 13M, and 13C are uniformly and uniformly charged.

  The developing units 16Bk, 16Y, 16M, and 16C are, for example, coated with urethane rubber in which carbon black is dispersed on the outer periphery of a metal shaft such as stainless steel, and the surface thereof is subjected to an isocyanate treatment. The developing units 16Bk, 16Y, 16M, and 16C are disposed so as to be in pressure contact with the surfaces of the image carriers 13Bk, 13Y, 13M, and 13C, and are formed on the surfaces of the image carriers 13Bk, 13Y, 13M, and 13C. A developer is supplied to the image to develop the developer image. Developer blades 19Bk, 19Y, 19M, and 19C for thinning the developer supplied from the developer supply rollers 18Bk, 18Y, 18M, and 18C are provided on the surfaces of the developing devices 16Bk, 16Y, 16M, and 16C. .

  The developer supply rollers 18Bk, 18Y, 18M, and 18C are configured, for example, by coating a semiconductive foamed silicone sponge layer on the outer periphery of a metal shaft such as stainless steel. The developer supply rollers 18Bk, 18Y, 18M, and 18C are arranged so as to be in pressure contact with the developing devices 16Bk, 16Y, 16M, and 16C, and the developments housed in the developer cartridges 20Bk, 20Y, 20M, and 20C. The developer is supplied to the developing devices 16Bk, 16Y, 16M, and 16C.

  The developer cartridges 20Bk, 20Y, 20M, and 20C are box-shaped members having a space for storing unused developer. A shutter (not shown) for supplying the developer to the developer supply rollers 18Bk, 18Y, 18M, and 18C is formed below the developer cartridges 20Bk, 20Y, 20M, and 20C. The developed developer is supplied to the developer supply rollers 18Bk, 18Y, 18M, and 18C.

  At positions facing the image carriers 13Bk, 13Y, 13M, and 13C included in each image forming unit, a transfer roller 17Bk that transfers the developer images developed on the image carriers 13Bk, 13Y, 13M, and 13C to a sheet. , 17Y, 17M, and 17C. The transfer rollers 17Bk, 17Y, 17M, and 17C have a configuration in which a urethane sponge layer is coated on a metal shaft, and the image carriers 13Bk, 13Y, 13M, and 13C are applied with a predetermined transfer voltage applied from a transfer voltage power source (not shown). The developer image developed on the surface is transferred to a sheet.

  Although not shown in FIG. 1, as other members constituting the printer 11, the printer 11 includes a microprocessor, a ROM (Read Only Memory), a RAM (Random Access Memory), an input / output port, a timer, and the like. A print control unit, an interface control unit that receives print data and control commands, controls the entire sequence of the printer 11 and executes a print operation, and temporarily stores print data input via the interface control unit Receiving memory, print data stored in the receiving memory, and editing the print data to display the image data editing memory for storing the formed image data (image data) and the status of the printer 11 For example, a display unit including a display device such as an LCD (Liquid Crystal Display), from a user For example, an operation unit having an input means such as a touch panel, for example, various sensors such as a paper position detection sensor, a temperature / humidity sensor, and a density sensor for monitoring the operation state of the printer 11, image data editing The image data stored in the memory is sent to LED heads 15Bk, 15Y, 15M, and 15C, which will be described later, and the temperature of the fixing device 24, which controls the driving of the LED heads 15Bk, 15Y, 15M, and 15C, is controlled. A temperature controller, a paper transport motor controller for controlling a drive motor for rotating each roller for transporting paper, a drive controller for controlling a drive motor for rotating various rollers such as an image carrier, or the like A high voltage power supply for applying a voltage to the roller is provided.

  As described above, the LED heads 15Bk, 15Y, 15M, and 15C as exposure apparatuses emit light based on image data on the surface of the image carriers 13Bk, 13Y, 13M, and 13C included in the image forming units 12Bk, 12Y, 12M, and 12C. To form an electrostatic latent image. Such LED heads 15Bk, 15Y, 15M, and 15C are arranged so that the emitted light is positioned on the surfaces of the respective image carriers 13Bk, 13Y, 13M, and 13C. Below, the structure of LED head 15Bk, 15Y, 15M, and 15C is demonstrated in detail. Since the LED heads 15Bk, 15Y, 15M, and 15C have the same configuration, the following description omits the alphabet notation for identifying the LED heads 15Bk, 15Y, 15M, and 15C. .

  FIG. 2 is an exploded perspective cutaway view of the LED head 15 according to the present embodiment. FIGS. 3 and 4 are cross-sectional views when the LED heads of portions A and B in FIG. 2 are assembled, and FIG. FIG. The LED head 15 includes an LED array chip 5 composed of LEDs as a plurality of light emitting elements mounted on the glass epoxy substrate 6, and serves as a converging lens that converges light emitted from the LED array chip 5 on the substrate 6. The rod lens array 2 is held by a holder 1 as a holding member.

  A holder opening 1a is formed in the center of the holder 1 along its longitudinal direction, and the rod lens array 2 is inserted into the holder opening 1a. Here, as shown in FIG. 3, the position where the incident distance Lo between the end surface where the light is incident on the rod lens array 2 and the surface of the LED array chip 5 becomes the optimum Lo value in terms of the characteristics of the rod lens array 2. The rod lens array 2 is fixed to the holder 1 with an adhesive (not shown). Further, the gap between the holder 1 and the rod lens array 2 is sealed with a rod lens array sealant 35 in order to prevent light and foreign matter from entering the holder 1.

  By the way, the holder 1 is manufactured by sheet metal pressing or the like, and a holder receiving portion 1b bent from the side surface portion so as to be parallel to the rod lens array 2 is formed, and a hardener contact is made on the holder receiving portion 1b. A surface 7 is formed. The hardener contact surface 7 is formed of, for example, an ultraviolet curable resin, an epoxy adhesive, or an acrylic adhesive. The holder receiving portion 1b and the hardener contact surface 7 are formed at a plurality of locations along the longitudinal direction of the rod lens array 2 as shown in FIG.

  Then, the substrate 6 is brought into contact with the curing agent contact surface 7, and further, a sheet 9 as a sheet member made of a resin such as PET (polyethylene terephthalate) is stacked on the back surface of the substrate 6, and the substrate presser is placed thereon. The base 8 as a member is pushed in, the base fitting portion 8b is fitted into the fitting hole 1d of the holder 1, and the base 8 is fixed, thereby fixing the substrate 6.

  Thereafter, the boundary between the holder 1 and the base 8, the opening 8d of the base, and the fitting hole 1d of the holder 1 are sealed with a sealing agent 36 such as silicone, and the side hole 1c opened for forming the holder receiving portion 1b. It shields by sticking the shielding sheet 30 on.

  Note that an eccentric cam mechanism 10 as shown in FIG. 5 is provided at both ends in the longitudinal direction of the LED head 15 as shown in FIG. 5, and the light is imaged on the end surface irradiated with light in the rod lens array 2. The output distance Li from the target position O can be adjusted at a position where Li = Lo.

  Next, the base 8 and the sheet 9 according to this embodiment will be described in more detail. FIG. 6 is an explanatory diagram in which the vicinity of the clamp portion 8 a in the base 8 is enlarged for explaining the positional relationship between the base 8 and the sheet 9.

  The base 8 is provided with a substrate abutting portion 8e for fixing the substrate 6 by sandwiching the substrate 6 with the curing agent abutting surface 7 so as to cross the base 8. The elastic clamp portion 8a is a substrate. It arrange | positions between the contact parts 8e. The opening 8d as the second opening is arranged at both ends of the base 8 and in the vicinity of the substrate contact portion 8e, on the opposite side of the slit 8c as the first opening with the substrate contact portion 8e interposed therebetween. ing.

  In the sheet 9, a sheet (sealing portion) 9 a which is a portion overlapping the clamp portion 8 a of the base 8 covers the side surface of the holder 1 in a state where the LED head 15 is folded, and an edge portion is formed between the holder 1 and the base 9. In order to be able to be sealed at a time when the boundary between the base 8 and the holder 1 is sealed, the protruding width from the base 8 is the application width of the sealant 36. (1 mm) and below. The length of the sheet (sealing part) 9a is designed so that the end of the sheet (sealing part) 9a is exposed in the opening 8d. Thus, when the opening 8d is sealed, the edge of the sheet (sealing portion) 9a and the corner of the substrate contact portion 8e where a gap is likely to be generated and the portion where the bent portion of the sheet 9 is in contact are surely sealed. Can do.

  The sheet (sealing portion) 9a includes a groove 9b. As shown in the longitudinal sectional view of FIG. 7, the groove 9b is for avoiding the fitting portion 8b of the base 8 and preventing the fitting hole 1d of the holder 1 from being blocked. In this case, the outer edge portion of the fitting hole 1d and the groove 9b of the sheet (sealing portion) 9a are designed to coincide with each other.

  Next, an image forming process of the printer 11 to which the LED head 15 is applied will be described.

  First, when print data is input to the printer 11 and image data based on the print data is generated, the printer 11 starts an image forming process. At the start of the image forming process, the paper stored in the paper storage cassette 21 is fed out to the paper transport path one by one by the rotation of the hopping roller 26 rotated by driving of a drive motor (not shown). Thereafter, the sheet is conveyed to the image forming units 12Bk, 12Y, 12M, and 12C along the sheet conveyance path while the skew is corrected by the registration roller 22. Then, the following image forming process is started at a predetermined timing until the sheet is conveyed to the image forming units 12Bk, 12Y, 12M, and 12C.

  When image data is generated for the printer 11, the image carriers 13Bk, 13Y, 13M, and 13C are rotated at a constant peripheral speed in a predetermined direction by a driving force transmitted from a driving unit (not shown). The chargers 14Bk, 14Y, 14M, and 14C provided in contact with the surfaces of the image carriers 13Bk, 13Y, 13M, and 13C apply a charging bias applied from a high-voltage power source (not shown) to the image carriers 13Bk, 13Y, and 13C. Applied to the surfaces of 13M and 13C to uniformly and uniformly charge the surfaces. Next, light corresponding to the image data is sent to the image carriers 13Bk, 13Y, 13M, and 13C by the LED heads 15Bk, 15Y, 15M, and 15C provided to face the surfaces of the image carriers 13Bk, 13Y, 13M, and 13C. Irradiated, the potential of the light-irradiated part is attenuated and an electrostatic latent image is formed.

  The developing devices 16Bk, 16Y, 16M, and 16C develop the developer image by attaching the developer to the electrostatic latent images formed on the surfaces of the image carriers 13Bk, 13Y, 13M, and 13C.

  The developer images on the surfaces of the image carriers 13Bk, 13Y, 13M, and 13C are transferred onto a sheet by transfer rollers 17Bk, 17Y, 17M, and 17C to which a predetermined transfer bias is applied by a high voltage power source (not shown).

  Thereafter, the sheet is conveyed to a fixing device 24 having a heat roller 24a and a backup roller 24b. The sheet on which the developer image has been transferred is controlled by a temperature control unit (not shown) and is conveyed to a pressure contact portion formed by a heat roller 24a and a backup roller 24b maintained at a predetermined surface temperature. Then, the developer is melted by the heat applied from the heat roller 24a, and further pressed by the pressure contact portion, whereby the developer image is fixed on the paper.

  The sheet on which the developer image is fixed is discharged to the discharge stacker 25, and a series of image forming processes is completed.

  Note that some developer may remain on the surfaces of the image carriers 13Bk, 13Y, 13M, and 13C after the developer image is transferred. The remaining developer is removed by a cleaning blade (not shown). The image carrier 13Bk, 13Y, 13M, 13C rotates about the rotation axis while the cleaning blade is in contact with the surface of the image carrier 13Bk, 13Y, 13M, 13C, so that the image carrier 13Bk, The developer remaining on the surfaces of 13Y, 13M, and 13C is removed. The cleaned image carriers 13Bk, 13Y, 13M, and 13C are repeatedly used in the next image forming process.

  As described above, according to the present embodiment, the substrate contact portion and the sheet of the base, and the boundary between the base and the holder and the opening of the base are sealed with the sealing agent, so that the foreign substance mixing path from the slit of the base is reduced. Since it can be closed, it is not necessary to fill the slit with a sealing agent, thereby improving the disassembly performance while ensuring the sealing performance for preventing foreign matter from entering.

  In the description of the present embodiment, an example in which the holder is manufactured by sheet metal press working has been described. However, the present invention is not limited to this, and a holder manufactured by aluminum die casting or resin injection molding, or a combined molding holder of sheet metal + mold. It can be applied to an exposure apparatus. In the description of the present embodiment, the example in which the hardener contact surface is provided on the holder receiving surface formed by bending the sheet metal has been described. However, the exposure apparatus that does not use the hardener contact surface at the place where the substrate contacts. In addition, the present invention is applicable.

DESCRIPTION OF SYMBOLS 1 Holder 1a Holder opening part 1b Holder receiving part 1c Side hole 1d Fitting hole 2 Rod lens array 5 LED array chip 6 Substrate 7 Hardener contact surface 8 Base 8a Clamping part 8b Fitting part 8c Slit 8d Opening part 8e Substrate contact part 9 sheet 9a sheet (sealing part)
9b Groove 10 Eccentric cam mechanism 11 Printer 12Bk, 12Y, 12M, 12C Image forming unit 13Bk, 13Y, 13M, 13C Image carrier 14Bk, 14Y, 14M, 14C Charger 15Bk, 15Y, 15M, 15C LED head 16Bk, 16Y, 16M, 16C Developers 17Bk, 17Y, 17M, 17C Transfer rollers 18Bk, 18Y, 18M, 18C Developer supply rollers 19Bk, 19Y, 19M, 19C Developer blades 20Bk, 20Y, 20M, 20C Developer cartridge 21 Paper storage cassette 22 Registration roller 23 Conveyor belt 23a Drive roller 23b Tension roller 24 Fixing device 24a Heat roller 24b Backup roller 25 Discharge stacker 26 Hopping roller 27 Paper color measuring unit 30 Shielding sheet 35 Rod Lens array sealant 36 Sealant

Claims (8)

A substrate on which a light emitting element is arranged in a predetermined direction;
A holding member for holding the substrate;
A substrate pressing member having a fitting portion of an elastic body to be fitted with the holding member, and a first opening disposed at a position facing the fitting portion;
A sheet member disposed between the substrate and the substrate pressing member;
An exposure apparatus, wherein a sealant is disposed between the holding member and the substrate pressing member, and the sheet member is formed to be exposed from the first opening. The exposure apparatus according to claim 1, wherein the substrate pressing member includes a substrate contact portion that contacts the substrate. The exposure apparatus according to claim 2, wherein the fitting portion is provided between the substrate contact portions. The said board | substrate holding member is equipped with the 2nd opening part located on both sides and an other side on both sides of the said board | substrate contact part with respect to the said 1st opening part. The exposure apparatus described in 1. The said sheet | seat member has the width | variety which covers the side surface of the said holding member, and an edge part is pinched | interposed between the said holding member and the said board | substrate holding member. The exposure apparatus described. The exposure apparatus according to any one of claims 1 to 5, wherein the sheet member has an edge portion exposed to the second opening. The exposure apparatus according to any one of claims 1 to 6, wherein the sheet member includes a groove that avoids a portion where the holding member and the substrate pressing member are engaged with each other. An exposure apparatus according to any one of claims 1 to 7,
An image forming apparatus comprising: an image forming unit that develops an electrostatic latent image formed by the exposure device and forms a developer image.