JP2019034504A - Exposure apparatus and image forming apparatus - Google Patents

Abstract

An exposure apparatus and an image forming apparatus capable of easily removing a sealing material and improving the reusability of a member. A substrate 33 on which a plurality of light emitting elements 31 are mounted, an optical system 32 for converging light emitted from the light emitting elements, and inner wall portions 341 and 342 forming spaces for accommodating the substrate and the optical system are provided. The gap between the inner wall portion and the optical system is sealed with a sealing material 52 from the side where the substrate is accommodated. [Selection] Figure 3

Description

  The present invention relates to an exposure apparatus and an image forming apparatus having a lens array.

  The conventional exposure apparatus does not pass through the lens array out of the emitted light emitted from the semiconductor light emitting element after fixing the lens array in which the lenses are arranged to the support member at a predetermined position with an adhesive or the like at a predetermined position. Seal the gap between the support member and the lens array with a low-transmittance sealing material to prevent ambient light from leaking to the outside and prevent foreign matter from entering the support member from the outside. (For example, refer to Patent Document 1).

JP 2009-73041 A

However, in the conventional technique, the sealing material that seals the gap between the support member and the lens array is disposed on the outer surface side of the exposure apparatus that can be touched, so that even if it is touched, it does not easily peel off. Because it is adhesive, if a defect occurs in the lens array or the support member in the assembly process of the exposure apparatus, it becomes difficult to remove the sealing material, and the lens array or the support member can be reused. There is a problem that it may be difficult.
An object of the present invention is to solve such a problem, and an object of the present invention is to facilitate removal of a sealing material and improve reusability of a member.

  Therefore, the present invention has a substrate on which a plurality of light emitting elements are mounted, an optical system that converges light emitted from the light emitting elements, and an inner wall portion that forms a space for accommodating the substrate and the optical system. A gap between the inner wall portion and the optical system is sealed with a sealing material from the side where the substrate is accommodated.

  The present invention thus configured has the effect of allowing the use of a non-adhesive sealing material, facilitating the removal of the sealing material, and improving the reusability of the member.

Schematic side sectional view of an image forming apparatus in an embodiment External perspective view of exposure apparatus in embodiment Sectional drawing of the transversal direction of the LED head in an Example Sectional perspective view of the principal part of the LED head in an Example Sectional drawing of the longitudinal direction of the LED head and photosensitive drum in an Example Sectional view of LED head and photoconductor drum in lateral direction in embodiment Sectional view of LED head and photoconductor drum in lateral direction in embodiment Explanatory drawing which shows the manufacturing method of the exposure apparatus in an Example Explanatory drawing which shows the manufacturing method of the exposure apparatus in an Example Explanatory drawing which shows the manufacturing method of the exposure apparatus in an Example Explanatory drawing which shows the manufacturing method of the exposure apparatus in an Example Explanatory drawing which shows the manufacturing method of the exposure apparatus in an Example

  Embodiments of an exposure apparatus and an image forming apparatus according to the present invention will be described below with reference to the drawings.

  FIG. 1 is a schematic sectional side view of an image forming apparatus according to an embodiment.

  In FIG. 1, an image forming apparatus 11 includes an exposure device, and is, for example, an electrophotographic color printer. The image forming apparatus 11 includes a conveyance belt 21, a hopping roller 22, a registration roller 23, a paper storage cassette 24, an image forming unit 12 (12Bk, 12Y, 12M, 12C), a fixing device 26, and a discharge roller 27. And a stacker 28.

The paper storage cassette 24 stores printing paper (hereinafter referred to as “paper”) as a recording medium in a stacked manner. In addition to printing paper, OHP paper (sheet), envelopes, copy paper, special paper, etc. can be used as the recording medium.
The hopping roller 22 rotates to feed out the paper stored in the paper storage cassette 24 one by one and send it to the registration roller 23 downstream in the medium conveyance direction indicated by the arrow A in the figure.

The registration roller 23 is disposed downstream of the hopping roller 22 in the medium conveyance direction, and rotates to convey the sheet conveyed from the hopping roller 22 to the conveyance belt 21. The registration roller 23 corrects the skew of the paper fed by the hopping roller 22.
The paper storage cassette 24, the hopping roller 22, and the registration roller 23 constitute a paper feeding mechanism that feeds paper. A paper color measurement unit 25 that measures the color of the paper stored in the paper storage cassette 24 is disposed above the paper storage cassette 24.

  The conveyance belt 21 is disposed downstream of the registration rollers 23 in the medium conveyance direction, and is rotatably stretched between two rollers. The conveyance belt 21 rotates in the medium conveyance direction indicated by the arrow A in the drawing, and conveys the sheet conveyed by the registration roller 23 to the fixing device 26. Further, four image forming units 12 (12Bk, 12Y, 12M, and 12C) are disposed above the conveyance belt 21.

  The image forming unit 12 (12Bk, 12Y, 12M, 12C) is composed of four independent image forming units 12Bk, 12Y, 12M, 12C. The image forming unit 12 (12Bk, 12Y, 12M, 12C) is formed from the upstream sheet insertion side in the medium transport direction along the transport belt 21. On the discharge side, the image forming unit 12Bk, the image forming unit 12Y, the image forming unit 12M, and the image forming unit 12C are arranged in this order. The image forming unit 12Bk forms black (Bk), the image forming unit 12Y forms yellow (Y), the image forming unit 12M forms magenta (M), and the image forming unit 12C forms cyan (C). In this embodiment, the image forming unit 12 is described as four image forming units. However, three or less or five or more image forming units may be provided, and the arrangement order of the image forming units is limited to that described above. It is not a thing.

  The image forming units 12Bk, 12Y, 12M, and 12C include photosensitive drums 13Bk, 13Y, 13M, and 13C, charging rollers 14Bk, 14Y, 14M, and 14C, developing rollers 16Bk, 16Y, 16M, and 16C, and a toner supply roller 18Bk. , 18Y, 18M, 18C, developing blades 19Bk, 19Y, 19M, 19C, and toner cartridges 20Bk, 20Y, 20M, 20C.

On the photosensitive drums 13Bk, 13Y, 13M, and 13C as image carriers, electrostatic latent images are formed by LED (Light Emitting Diode) heads 15Bk, 15Y, 15M, and 15C, which will be described later, and a developer is formed on the electrostatic latent images. A toner image as a developer image is formed by the toner as described above and is rotatable.
The charging rollers 14Bk, 14Y, 14M, and 14C as the chargers uniformly and uniformly charge the surfaces of the photosensitive drums 13Bk, 13Y, 13M, and 13C.

The developing rollers 16Bk, 16Y, 16M, and 16C as developer carriers adhere toner to the electrostatic latent images formed on the surfaces of the photosensitive drums 13Bk, 13Y, 13M, and 13C, and display each color as a visible image. A toner image is formed.
The toner supply rollers 18Bk, 18Y, 18M, and 18C as the developer supply members are disposed so as to come into contact with the development rollers 16Bk, 16Y, 16M, and 16C, and the toner supplied from the toner cartridges 20Bk, 20Y, 20M, and 20C. Is supplied to the developing rollers 16Bk, 16Y, 16M, and 16C.

The developing blades 19Bk, 19Y, 19M, and 19C are disposed so as to be in contact with the developing rollers 16Bk, 16Y, 16M, and 16C, and the toner supply rollers 18Bk, 18Y, 18M, and 18C are provided on the developing rollers 16Bk, 16Y, 16M, and 16C. The toner supplied from is thinned.
The toner cartridges 20Bk, 20Y, 20M, and 20C as the developer storage units store toner therein and supply the toner to the toner supply rollers 18Bk, 18Y, 18M, and 18C.

  LED heads 15Bk, 15Y, 15M, and 15C as exposure devices are disposed above the photosensitive drums 13Bk, 13Y, 13M, and 13C and at positions facing the photosensitive drums 13Bk, 13Y, 13M, and 13C. Is. The LED heads 15Bk, 15Y, 15M, and 15C expose the photosensitive drums 13Bk, 13Y, 13M, and 13C according to the image data of each color, and form electrostatic latent images on the surfaces of the photosensitive drums 13Bk, 13Y, 13M, and 13C. Device. The LED heads 15Bk, 15Y, 15M, and 15C are formed to extend in the medium width direction orthogonal to the medium transport direction.

Below the image forming units 12Bk, 12Y, 12M, and 12C, a transfer unit that includes transfer rollers 17Bk, 17Y, 17M, and 17C and a transport belt 21 that rotates and travels in the medium transport direction indicated by an arrow A in the drawing. It is installed.
The transfer rollers 17Bk, 17Y, 17M, and 17C are arranged to face the respective photosensitive drums 13Bk, 13Y, 13M, and 13C with the conveying belt 21 therebetween, and charge the sheet to a polarity opposite to that of the toner, thereby the photosensitive drum 13Bk. , 13Y, 13M, and 13C are rollers for transferring toner images formed on the paper.

The fixing device 26 is disposed on the paper discharge side, which is the downstream side of the conveyance belt 21 in the medium conveyance direction, and fixes the toner image transferred onto the paper by the transfer rollers 17Bk, 17Y, 17M, and 17C. The fixing device 26 includes a heating roller and a backup roller, and fixes the toner transferred onto the paper by pressurizing and heating.
The discharge roller 27 is disposed downstream of the fixing device 26 in the medium conveyance direction, and discharges the paper conveyed from the fixing device 26 to the outside of the image forming apparatus 11.

The stacker 28 stacks and stores the sheets discharged by the discharge roller 27.
2 is an external perspective view of the exposure apparatus in the embodiment, FIG. 3 is a cross-sectional view in the short direction of the LED head in the embodiment, and FIG.

  2 to 4 are the LED heads 15Bk, 15Y, 15M, and 15C shown in FIG. 1, and the LED heads 15Bk, 15Y, 15M, and 15C have the same configuration. In this embodiment, the LED head 15Bk will be described as an example.

  3 is a cross-sectional view of the LED head cut in the short direction (sub-scanning direction), and FIG. 4B is an enlarged view of the cross-section of the LED head in FIG. 4A cut in the short direction. It is a perspective view.

  2 to 4, an LED head 15 as an exposure apparatus is formed so as to extend in a direction (main scanning direction) perpendicular to the medium transport direction indicated by an arrow A in FIG. 1, and includes an LED array chip 31 and a rod. A lens array 32, a substrate 33, a lens array holder 34, a plate 35, and a coil spring 37 are provided. The LED head 15 is, for example, the LED head 15Bk shown in FIG.

The LED array chip 31 as a light emitting element is arranged to face the photosensitive drum 13Bk shown in FIG. 1, and has a plurality of light emitting diodes (LEDs) arranged therein.
The rod lens array 32 as an optical system is formed in an elongated shape and is disposed between the LED array chip 31 and the photosensitive drum 13Bk shown in FIG. A plurality of rod lenses for converging the emitted light are arranged.

The LED array chip 31 and the rod lens array 32 are arranged so that the optical axes L of the respective LEDs and the respective rod lenses coincide.
The substrate 33 is formed in a long shape and is mounted with a plurality of light emitting elements, and is mounted with an LED array chip 31 and a driver IC for controlling the LED array chip 31.

The lens array holder 34 as a support member is formed in a long shape, and supports both side portions extending in the longitudinal direction of the long rod lens array 32 and the substrate 33. The lens array holder 34 is a plastic product formed by pouring a resin material into a mold.
The lens array holder 34 has an inner wall portion 341 and an inner wall portion 342 that extend in the longitudinal direction and are opposed in the short-side direction, and the rod lens array 32 and the substrate 33 are interposed between the inner wall portion 341 and the inner wall portion 342. The first region R1, the second region R2, and the third region R3 are formed.

The inner wall portion 341 and the inner wall portion 342 support the both sides extending in the longitudinal direction of the rod lens array 32 and the substrate 33 in the space in which the rod lens array 32 and the substrate 33 are accommodated.
The inner wall portion 341 includes a first inner wall portion 341a, a second inner wall portion 341b, and a third inner wall portion 341c, and the inner wall portion 342 includes the first inner wall portion 342a and the second inner wall portion 342b. And a third inner wall portion 342c.

The inner wall portion 341 and the inner wall portion 342 are arranged between the first inner wall portion 341a and the first inner wall portion 342a in the first region R1, and between the second inner wall portion 341b and the second inner wall portion 342b. A third region R3 is formed between the second region R2, the third inner wall portion 341c, and the third inner wall portion 342c.
The plate 35 as a positioning member determines the distance between the rod lens array 32 and the photosensitive drum 13Bk shown in FIG.

The coil spring 37 biases the LED head 15 toward the photosensitive drum 13 (for example, the photosensitive drum 13Bk) shown in FIG.
As shown in FIG. 3, a space penetrating from the lower side (photosensitive drum 13 </ b> Bk shown in FIG. 1) to the upper side (LED array chip 31 side) is formed inside the lens array holder 34. A first region R1, a second region R2, and a third region R3 are formed from below to above.

  The first region R1 is a space for housing the rod lens array 32. As shown in FIG. 4, a concave portion 34a, an inclined portion 34b, and an opening portion 34d are formed in the first inner wall portions 341a and 342a of the lens array holder 34 forming the first region R1. . In addition, ribs 34c are formed in the first region R1 and the second region R2.

  A plurality of concave portions 34a are formed in the longitudinal direction (main scanning direction) of the first inner wall portions 341a and 342a of the lens array holder 34, and are formed at positions facing each other across the rod lens array 32 (in the first region R1). It has been done.

  The inclined portion 34b is formed on the upper side (the first region R1 of the first region R1) on both sides in the longitudinal direction of the first inner wall portions 341a and 342a of the lens array holder 34 arranged to face each other via the rod lens array 32. It is formed so as to extend in the longitudinal direction (upward). The inclined portion 34b is formed to be inclined toward the rod lens array 32 from the upper side to the lower side.

  The ribs 34c as the protrusions are arranged so as to sandwich the upper part of the rod lens array 32, and are two members disposed at positions facing the inclined part 34b so as to extend in the longitudinal direction of the lens array holder 34. It is. The ribs 34 c are supported at both ends in the longitudinal direction of the lens array holder 34 and are formed so as to protrude toward the LED array chip 31.

  Thus, the rib 34c extends from one end side to the other end side along the longitudinal direction of the rod lens array 32 in the longitudinal direction of the lens array holder 34, and in the lateral direction of the lens array holder 34, A plurality (two) of rod lenses array 32 are formed.

  The opening 34d is formed at a position closer to the LED array chip 31 than the incident surface 32a on the LED array chip 31 side of the rod lens array 32, and is formed so as to extend in the longitudinal direction of the lens array holder 34. 1 is an opening formed between the inclined portion 34 b of the inner wall portions 341 a and 342 a, the rib 34 c and the rod lens array 32 and sealed with the first silicon material 52.

The second region R2 is formed between the second inner wall portion 341b of the lens array holder 34 on the LED array chip 31 side of the first region R1 and the second inner wall portion 342b. It is a space formed so as to communicate with R1.
On the inner surface side of the second inner wall portions 341b and 342b of the lens array holder 34 forming the second region R2, a plurality of substrate support portions 34e arranged to face each other are arranged in the longitudinal direction of the lens array holder 34. ing. A contact surface S1 that contacts the substrate 33 is formed on the upper surface of each substrate support portion 34e, and the substrate 33 is supported by the contact surface S1 of each substrate support portion 34e.

The third region R3 is formed between the third inner wall portion 341c of the lens array holder 34 on the LED array chip 31 side of the second region R2 and the third inner wall portion 342c. It is a space formed so as to communicate with R2.
The rod lens array 32 is disposed in the first region R <b> 1, and the first adhesive 51 is applied to the plurality of recesses 34 a formed in the lens array holder 34 and is fixed to the lens array holder 34.

  Further, after the rod lens array 32 is fixed to the lens array holder 34, the rod lens array 32 is formed between the first inner wall portion 341a and the inclined portion 34b and the rib 34c formed on the first inner wall portion 342a of the lens array holder 34. The gap is sealed by the first silicon material 52 injected from the opening 34d on the side where the substrate 33 is accommodated.

  The first silicon material 52 as a sealing material prevents the disturbance light that does not pass through the rod lens array 32 out of the radiated light emitted from the LED array chip 31 from exposing the photosensitive drum 13Bk shown in FIG. In order to prevent foreign matter from entering the lens array holder 34 from the outside, the light transmittance is low, the adhesiveness is weak, the viscosity is high, and the viscosity is 80 to 400 [Pa · s] (Pascal second). The first silicon material 52 does not contain an adhesive component.

  Here, the rib 34 c is formed so as to protrude from the first silicon material 52 toward the LED array chip 31, and is formed so as to sandwich the incident surface 32 a of the rod lens array 32. The rib 34 c formed in this manner suppresses the first silicon material 52 from adhering to the incident surface 32 a of the rod lens array 32.

  The substrate 33 is disposed in the third region R3 so as to contact the contact surface S1 of the substrate support portion 34e of the second inner wall portions 341b and 342b of the lens array holder 34 forming the second region R2. Placed in. The substrate 33 is fixed to the third inner wall portions 341c and 342c, which are the inner wall surfaces of the lens array holder 34 in the third region R3, at a plurality of locations in the longitudinal direction of the lens array holder 34 with the second adhesive 53. Thereafter, the gap between the lens array holder 34 and the lens array holder 34 is sealed with a second silicon material 54 as a sealing material with low adhesiveness.

In the present embodiment, the viscosity of the second silicon material 54 is set to 80 to 400 [Pa · s] similarly to the first silicon material 52.
As described above, in this embodiment, the rod lens array 32 is disposed so as to face the LED array chip 31 of the substrate 33 and is supported by the first inner wall portions 341a and 342a of the lens array holder 34, and on the LED array chip 31 side. A gap formed between the end portions of the first inner wall portion 341 a and the first inner wall portion 342 a of the lens array holder 34 and the rod lens array 32 is sealed with a first silicon material 52.

The rib 34 c is formed so as to protrude from the first silicon material 52 toward the LED array chip 31.
FIG. 5 is a sectional view in the longitudinal direction of the LED head and the photosensitive drum in the embodiment, and FIGS. 6 and 7 are sectional views in the lateral direction of the LED head and the photosensitive drum in the embodiment. 6 is a cross-sectional view taken along arrow AA in FIG. 5, and FIG. 7 is a cross-sectional view taken along arrow BB in FIG.

  5 to 7 are the LED heads 15Bk, 15Y, 15M, and 15C and the photosensitive drums 13Bk, 13Y, 13M, and 13C shown in FIG. Since the positional relationship between the LED heads 15Bk, 15Y, 15M, and 15C and the respective photosensitive drums 13Bk, 13Y, 13M, and 13C has the same configuration, one of the LED heads 15Bk and the photosensitive member is the same. An example of the drum 13Bk will be described.

  5 and 6, in order to accurately form light on the surface of the photosensitive drum 13, the surface of the LED array chip 31 and the incident surface 32a of the rod lens array 32 (end surface on which light is incident). And the distance in the optical axis L direction between the light emitting surface of the rod lens array 32 and the surface of the photosensitive drum 13 is Li. Therefore, it is necessary to adjust so that the distance Lo and the distance Li substantially coincide (distance Lo≈distance Li).

  In order to adjust the distance Lo and the distance Li, as shown in FIGS. 5 and 7, the distance Li between the rod lens array 32 and the photosensitive drum 13 is set at both ends of the lens array holder 34 in the longitudinal direction. Plates 35 are arranged as positioning members for determination. In addition, spacers 36 for regulating the distance Li are disposed on the surface of the photosensitive drum 13 at positions facing the respective plates 35.

A distance Li between the rod lens array 32 and the photosensitive drum 13 is regulated by the plate 35 and the spacer 36 that are disposed to face each other.
In addition, coil springs 37 are arranged as biasing members at positions facing the spacers 36 at both ends in the longitudinal direction of the lens array holder 34. Each coil spring 37 urges the LED head 15 in the direction of the photosensitive drum 13, and abuts each plate 35 on a contact surface of each spacer 36 to keep the distance Li constant.

  The operation of the above configuration will be described.

  First, the operation of the image forming apparatus will be described with reference to FIG.

The paper in the paper storage cassette 24 is fed out by the hopping roller 22 and sent to the registration roller 23. Subsequently, the sheet is fed from the registration roller 23 to the transport belt 21 and is transported to the image forming units 12Bk, 12Y, 12M, and 12C as the transport belt 21 travels.
In each of the image forming units 12Bk, 12Y, 12M, and 12C, the surfaces of the photosensitive drums 13Bk, 13Y, 13M, and 13C are charged by the charging rollers 14Bk, 14Y, 14M, and 14C, and the LED heads 15Bk, 15Y, 15M, and 15C are charged. Exposure is performed to form an electrostatic latent image.

The electrostatic latent images formed on the surfaces of the photosensitive drums 13Bk, 13Y, 13M, and 13C are electrostatically attached with a thin layer of toner on the developing rollers 16Bk, 16Y, 16M, and 16C. A toner image is formed.
The toner images formed on the surfaces of the photosensitive drums 13Bk, 13Y, 13M, and 13C are transferred onto the paper by the transfer rollers 17Bk, 17Y, 17M, and 17C, and a color toner image is formed on the paper. After the toner image is transferred, the toner remaining on the surfaces of the photosensitive drums 13Bk, 13Y, 13M, and 13C is removed by a cleaning device.

The sheet on which the color toner image is formed is sent to the fixing device 26. In the fixing device 26, a color toner image is fixed on a sheet, and a color image is formed. The sheet on which the color image is formed is sandwiched between the discharge rollers 27 and discharged to the sheet stacker 28.
In this way, a color image is formed on the paper through the electrophotographic process.

  Next, a method for manufacturing the LED head will be described with reference to FIGS. FIG. 8B is an enlarged view of the region F in FIG.

  First, as shown in FIG. 8, the side surfaces of the rod lens array 32 are attracted to a plurality of plates 101 provided in the jig 100, and the rod lens array 32 is made to follow each side surface of the rod lens array 32 with each plate 101. Hold straight. The plate 101 has a suction function and a true face, and sucks and holds the side surface of the rod lens array 32 in contact with the face (air suction in the direction indicated by the arrow G in FIGS. 9 to 12). It is.

Next, in order to straighten the exit end face of the rod lens array 32, the exit end face of the rod lens array 32 is pressed against the jig face 102 on which the straight face is formed, and the exit end face of the rod lens array 32 is copied to the jig face 102. Accordingly, the rod lens array 32 is held straight.
Thereby, the rod lens array 32 is corrected to be twisted and bent, and is corrected and held in a straight state with respect to the sub-scanning direction and the focus (optical axis) direction of the exposure apparatus.

  Next, as shown in FIGS. 9 and 10, the lens array holder 34 is inserted from above the rod lens array 32 into the region R1 that accommodates the rod lens array 32 and is held by a jig, and as shown in FIG. The position of the contact surface S1 of the substrate support 34e on which the substrate 33 is mounted is adjusted so that the distance from the incident surface 32a of the rod lens array 32 to the surface of the LED array chip 31 is the distance Lo, and the lens array holder 34 is adjusted. Move up and down to determine the position.

  Next, as shown in FIG. 10, the first adhesive 51 is applied to the plurality of recesses 34 a formed in the region R <b> 1 of the lens array holder 34, and the rod lens array 32 is fixed to the lens array holder 34. Accordingly, the rod lens array 32 is fixed to the lens array holder 34 so that the distance from the incident surface 32a of the rod lens array 32 to the surface of the LED array chip 31 is the distance Lo (see FIG. 6).

  Next, as shown in FIG. 11, a gap between the lens array holder 34 and the rod lens array 32 is applied and sealed with a first silicon material 52. That is, the first silicon material 52 is applied to the opening 34d between the inclined portion 34b on the inner surface side of the lens array holder 34 and the rib 34c.

At this time, the rib 34c is formed higher than the incident surface 32a of the rod lens array 32, that is, the incident surface 32a of the rod lens array 32 is disposed between the two ribs 34c. The silicon material 52 does not flow into the incident surface 32 a, and the incident surface 32 a can be prevented from being contaminated with the first silicon material 52.
Further, since the first silicon material 52 is a high-viscosity silicon material, the first silicon material 52 does not leak from the region R1 of the lens array holder 34 to the outer surface portion of the lens array holder 34.

  Next, as shown in FIG. 12, while maintaining the rod lens array 32 and the lens array holder 34 with the jig 100, the substrate 33 is inserted into the third region R3 formed in the lens array holder 34, The position of the substrate 33 is determined by contacting the contact surface S1 of the lens array holder 34.

Next, the second adhesive 53 is applied to the inner wall surfaces at a plurality of locations in the longitudinal direction of the lens array holder 34 in the third region R 3, and the substrate 33 is fixed to the lens array holder 34.
Next, a second silicon material 54 having a low adhesiveness is applied between the substrate 33 and the lens array holder 34 and sealed.

Next, the lens array holder 34 to which the rod lens array 32 is fixed is taken out of the jig 100, and as shown in FIGS. 5 and 7, the distance Li between the rod lens array 32 and the photosensitive drum 13 is the distance Lo. The plate 35 is adjusted with a jig so as to substantially match, and the plate 35 is adhered and fixed to both ends of the lens array holder 34.
The LED head is manufactured through such a manufacturing process.

  In the present embodiment, the first silicon material 52 that seals the gap between the lens array holder 34 and the rod lens array 32 is applied to the inner surface side of the lens array holder 34, so that the first silicon It becomes possible to weaken the adhesion of the material 52, and when the rod lens array 32 or the lens array holder 34 is defective in the assembly process of the LED head 15, the first silicon material 52 is easily removed. be able to.

  Further, even after the LED head 15 is assembled, even if a defect occurs on the substrate 33 on which the LED array chip 31 is mounted, the rod on the outer surface side of the lens array holder 34 (photosensitive drum 13 side shown in FIG. 6). Since the side surface of the lens array 32 is sufficiently exposed from the lens array holder 34, the side surface of the rod lens array 32 is again adsorbed by the jig 100 without removing the first silicon material 52. Twisting and bending can be straightened and held, and the LED head 15 can be easily assembled.

  Further, a rib 34c is provided over the longitudinal direction of the rod lens array 32 above the first region R1 (the substrate 33 side shown in FIG. 3), which is a space inside the lens array holder 34 that houses the rod lens array 32. The first silicon material is formed by forming the rib 34c higher than the incident surface 32a of the rod lens array 32, that is, by forming the incident surface 32a of the rod lens array 32 between the two ribs 34c. 52 does not flow into the incident surface 32a, and it is possible to suppress the incident surface 32a from being contaminated with the first silicon material 52.

  Further, even when the lens array holder 34 that supports the rod lens array 32 is made of a plastic having low rigidity, the rod lens array 32 is held in a straight state by correcting the twisting or bending of the rod lens array 32. At the same time, by fixing the substrate 33 on which the LED array chip 31 is mounted to the inner wall surface of the lens array holder 34, the rigidity of the lens array holder 34 is increased, and the lens array holder 32 is twisted or bent by the lens array holder 32. 34 is not pulled, and the state in which the twist and the bending of the rod lens array 32 are straightened can be maintained.

In this embodiment, the LED head 15 that does not have the focal height adjustment mechanism of the rod lens array 32 is described as an example. However, the LED head 15 that has the focal height adjustment mechanism may be used.
Further, the LED head 15 having the plastic lens array holder 34 formed by pouring resin into the mold has been described. However, the LED head 15 having the die array lens array holder 34 formed by pouring aluminum material into the mold. It is also good.

  As described above, in this embodiment, the silicon material for sealing the gap between the lens array holder and the rod lens array is applied to the inner surface side of the lens array holder, thereby assembling the LED head. In this case, it is possible to easily remove the sealing material when a defect occurs in the lens array holder or the rod lens array.

In addition, since the side surface of the rod lens array is sufficiently exposed from the lens array holder, the silicon material is not removed when a defect occurs in the lens array holder or the rod lens array in the LED head assembly process. As a result, it is possible to easily assemble the LED head.
Therefore, even when a defect occurs in the lens array holder or the rod lens array, the lens array holder or the rod lens array can be reused, and the repairability (reusability) can be improved. The effect is obtained.

  Furthermore, by forming the entrance surface of the rod lens array so as to be disposed between the two ribs, the silicon material is prevented from flowing into the entrance surface, and the entrance surface is prevented from being soiled with the silicon material. The effect of being able to be obtained.

  In addition, the rod lens array is corrected in a straightened state by holding the rod lens array in a straightened state, and at the same time, the substrate on which the LED array chip is mounted is fixed to the inner wall surface of the lens array holder. The rigidity of the array holder is increased, and the effect that the state in which the torsion and bending of the rod lens array are straightened can be maintained.

Therefore, it is possible to provide an LED head with stable quality.
In this embodiment, the image forming apparatus is described as a color printer. However, the present invention is not limited to this and may be a monochrome printer.

Further, although the image forming apparatus has been described as a printer, the present invention is not limited thereto, and may be a copier, a facsimile machine, or a multifunction peripheral (MFP).
Furthermore, the present invention has been described with reference to an example in which the present invention is applied to an exposure apparatus for an optical print head. However, the present invention is not limited to this. May be.

11 Image forming apparatus 12 (12Bk, 12Y, 12M, 12C) Image forming unit 13 (13Bk, 13Y, 13M, 13C) Photosensitive drum 15 (15Bk, 15Y, 15M, 15C) LED head 31 LED array chip 32 Rod lens array 33 Substrate 34 Lens array holder 34a Recess 34b Inclined portion 34c Rib 34d Opening 34e Substrate support portion 341, 342 Inner wall portion 35 Plate 37 Coil spring 51 First adhesive material 52 First silicon material 53 Second adhesive material 54 Second Silicone material

Claims (8)

A substrate on which a plurality of light emitting elements are mounted;
An optical system for converging the light emitted from the light emitting element;
A support member having an inner wall that forms a space for accommodating the substrate and the optical system;
Have
An exposure apparatus, wherein a gap between the inner wall portion and the optical system is sealed with a sealing material from a side where the substrate is accommodated. The exposure apparatus according to claim 1,
The optical system is disposed to face the light emitting element of the substrate and is supported by the inner wall portion,
The exposure apparatus according to claim 1, wherein the gap is a gap formed between the inner wall portion on the light emitting element side and the optical system. In the exposure apparatus according to claim 1 or 2,
The support member is
An exposure apparatus comprising a protrusion formed so as to protrude from the sealing material toward the light emitting element. In the exposure apparatus according to claim 3,
The support member is formed in a long shape, and supports both sides of the substrate formed in a long shape and the longitudinal direction of the optical system,
The protrusion is
In the longitudinal direction of the support member, it extends from one end side toward the other end side along the longitudinal direction of the optical system,
An exposure apparatus, wherein a plurality of the optical members are formed so as to sandwich the optical system in a short direction of the support member. In the exposure apparatus according to claim 3 or 4,
An exposure apparatus, wherein an opening sealed with the sealing material is formed between an inner wall of the support member, the protrusion, and the optical system. The exposure apparatus according to any one of claims 1 to 5,
The exposure apparatus according to claim 1, wherein the sealing material is a silicon material that does not contain an adhesive component. In the exposure apparatus according to any one of claims 1 to 6,
The exposure apparatus, wherein the sealing material has a viscosity of 80 to 400 [Pa · s].   An image forming apparatus comprising the exposure apparatus according to claim 1.

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