JP6232966B2 - Mounting jig - Google Patents

Description

The present invention is mounted jig again and again relates fitted into the fitting hole to hold the light source during assembly of the optical scanning device.

  2. Description of the Related Art Image forming apparatuses such as copying machines, facsimile machines, printers, and multifunction machines that employ an electrophotographic system are equipped with an optical scanning device that scans a photosensitive drum with light to form an electrostatic latent image on a peripheral surface. Yes. As a method of attaching the light source to the housing in the optical scanning device, for example, a method of attaching the light source to a holder separate from the housing and fixing the holder to the housing is known. However, in recent years, reduction of the number of parts is often required for cost reduction and the like, and the mounting method using a separate holder as described above has a problem that the number of parts increases. Therefore, a technique has been proposed in which a fitting hole for fitting a light source is provided in the housing, and the number of components is reduced by press-fitting the light source into the fitting hole (see, for example, Patent Document 1).

  However, in the technique described in Patent Literature 1, there is a problem that a load is applied to the light source because the light source is fitted into the fitting hole while the light source is tightened, and there is a possibility that the inner surface of the fitting hole is shaved and scraps are generated. There is a problem that there is. In this case, there is a possibility that an excessive load is applied to the light source, or scraps block the optical path. In the technique described in Patent Document 1, the entrance is blocked by an elastic member so that the generated scraps do not enter the inside of the housing, but problems such as load on the light source and generation of scraps are not suppressed. .

  Accordingly, an object of the present invention is to provide an attachment jig that can attach a light source to a housing while suppressing generation of a load and shavings applied to the light source when the optical scanning device is assembled.

In order to solve the above-described problem, the invention described in claim 1
A light source and a housing provided with a wall provided with a fitting hole narrower than the thickness of the light source at the time before the light source is fitted, and the scanning target is scanned with the light emitted from the light source. In the assembly of the optical scanning device for scanning, in the mounting jig that holds the light source and fits into the fitting hole,
The wall of the housing is provided with a recess surrounding the fitting hole,
When the light source is fitted into the fitting hole, an extension portion is provided which is inserted into the concave portion and expands the fitting hole by widening the interval between the portions of the concave portion sandwiching the fitting hole. The mounting jig is characterized by the fact that

  According to the mounting jig of the first aspect of the present invention, the light source is fitted into the fitting hole in a state where the fitting hole is expanded. Thereby, when the light source is fitted, the load applied to the light source is suppressed, and the generation of shavings is also suppressed. In other words, according to the mounting jig of the first aspect of the present invention, it is possible to attach the light source to the housing while suppressing the load applied to the light source and the generation of shavings during the assembly of the optical scanning device.

1 is a diagram illustrating an image forming apparatus according to an embodiment of the present invention. It is a disassembled perspective view of an optical scanning device. It is an expansion perspective view which shows the periphery of the light source in an optical scanning device. It is a perspective view which shows the attachment jig used for attachment of a laser diode. FIG. 5 is a cross-sectional view of the mounting jig shown in FIG. 4 along the line AA in FIG. 4. It is a figure which shows the state before the insertion to the insertion hole of a laser diode. It is a figure which shows the state in the insertion to the insertion hole of a laser diode. It is a figure which shows the state which removed the attachment jig after the insertion to the insertion hole of a laser diode.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a diagram illustrating an image forming apparatus according to an embodiment of the present invention.

  An image forming apparatus 1 shown in FIG. 1 forms an electrostatic latent image on a photosensitive drum 21, develops the electrostatic latent image with a developer, and transfers the developed image onto a recording medium. This is an image forming apparatus of the type. The image forming apparatus 1 is a printer that forms a monochrome image on a sheet P, that is, a sheet-like recording medium. As shown in FIG. 1, the image forming apparatus 1 includes a paper feed unit 3, a paper transport unit 4, a transfer roller 5, and a fixing device 6. In addition, the image forming apparatus 1 includes an optical scanning device 10 and one process cartridge 2. The process cartridge 2 is detachably mounted on the image forming apparatus 1.

  Two paper feed units 3 are provided below the process cartridge 2. These two paper supply units 3 differ in the size of the paper P to be stored. Each sheet feeding unit 3 accommodates a plurality of sheets P stacked one upon another.

  The paper transport unit 4 includes a pickup roller 41, a transport roller 42, a registration roller 43, and a discharge roller 44. In the paper transport unit 4, the pickup roller 41 feeds the paper P in the paper feed unit 3 one by one, and the transport roller 42 transports the transport path via the transfer roller 5 and the fixing device 6, and finally discharges the paper. The roller 44 discharges onto the discharge tray 1a. The registration roller 43 sends the paper P from the paper supply unit 3 to the transfer roller 5 in accordance with the timing at which the process cartridge 2 forms a toner image.

  The transfer roller 5 is opposed to a later-described photosensitive drum 21 of the process cartridge 2. The registration roller 43 sends out the paper P between the transfer roller 5 and the photosensitive drum 21. A transfer bias is applied to the transfer roller 5 by a high voltage power source (not shown). As a result, the transfer roller 5 transfers the toner image from the photosensitive drum 21 onto the paper P.

  The fixing device 6 receives the paper P on which the toner image has been transferred by the transfer roller 5, heats and pressurizes the paper P, and fixes the toner image on the paper P. The fixing device 6 includes a heating roller 61 and a pressure roller 62. The heat roller 61 has a heat source disposed therein, and heats the paper P with heat from the heat source. The peripheral surface of the pressure roller 62 is pressed against the heating roller 61 to form a nip portion, and the paper P is pressed. The pressure roller 62 is rotationally driven by a drive source (not shown), and the heating roller 61 is driven to rotate as the pressure roller 62 rotates. In the present embodiment, the heating roller 61 is employed as a member for heating the paper P. However, the member for heating the paper P may be an endless belt that is heated and circulated by a heat source.

The optical scanning device 10 scans and exposes the photosensitive drum 21 of the process cartridge 2 based on image information, and forms an electrostatic latent image on the outer peripheral surface of the photosensitive drum 21. In the present embodiment, the optical scanning device 10 uses a laser beam scanner system that includes a laser diode as a light source and performs scanning exposure by reflecting and irradiating light from the laser diode with a rotating polygon mirror. . The optical scanning device 10 will be described again later.

  The process cartridge 2 is detachably mounted on the image forming apparatus 1 and replaced with a new one as necessary. The process cartridge 2 is fixed at an arrangement position by a stopper (not shown). In the process cartridge 2, upon receiving scanning exposure from the optical scanning device 10, a toner image is formed by the components described below.

  The process cartridge 2 has a configuration in which a photosensitive drum 21, a charger 22, a developing device 23, and a cleaner 24 are integrally coupled.

The photosensitive drum 21 rotates counterclockwise in FIG. The outer peripheral surface of the photosensitive drum 21 corresponds to an example of the scanning target in the present invention. The charger 22 is in pressure contact with the outer peripheral surface of the photosensitive drum 21, and is rotated by the rotation of the photosensitive drum 21. The charger 22 charges the outer peripheral surface of the photosensitive drum 21. In this embodiment, a contact charging method in which a roller-shaped member is brought into contact for charging is used as the charging method. However, as the charging method, the charging member and the photosensitive drum are charged in a non-contact state. A non-contact charging method may be used. The outer peripheral surface of the photosensitive drum 21 charged by the charger 22 is scanned and exposed by the optical scanning device 10 described above, whereby an electrostatic latent image is formed on the outer peripheral surface. The electrostatic latent image is developed with a developer by the developing device 23, and a toner image is formed on the outer peripheral surface of the photosensitive drum 21. The formed toner image is transferred onto the paper P by the transfer roller 5. The deposits of the residual toner and the like remaining on the outer circumferential surface of the photosensitive drum 21 after the transfer is Ru is removed by the cleaner 24.

  This is the end of the description of the image forming apparatus 1. Next, the optical scanning device 10 will be described in detail.

  FIG. 2 is an exploded perspective view of the optical scanning device, and FIG. 3 is an enlarged perspective view showing the periphery of the light source in the optical scanning device.

  2 and 3, the optical scanning device 10 includes a housing 11, a laser diode 12, a collimating lens 13, an aperture 14, a cylindrical lens 15, a polygon mirror 17, a scanning lens 18, and an outgoing light reflecting mirror. 19.

  The housing 11 has a housing main body 11a and an upper cover 11b. The housing body 11a accommodates a collimating lens 13, an aperture 14, a cylindrical lens 15, a polygon mirror 17, a scanning lens 18, and an outgoing light reflecting mirror 19. As shown in FIG. 3, a fitting hole 11d is provided in the side wall 11c of the housing main body 11a, and the laser diode 12 is fitted into the fitting hole 11d. The fitting of the laser diode 12 into the fitting hole 11d will be described in detail later. The housing 11 corresponds to an example of a housing according to the present invention.

  The laser diode 12 receives an image signal sent from a control unit (not shown) and emits light modulated based on the image signal. This laser diode 12 corresponds to an example of a light source according to the present invention.

  The collimating lens 13 converts the divergent light beam emitted from the laser diode 12 into a parallel light beam. The aperture 14 is provided with a slit 14a through which light that has passed through the collimating lens 13 passes, and trims the cross-sectional shape of the light perpendicular to the optical path L to a predetermined shape. The cylindrical lens 15 condenses the light passing through the aperture 14 in the sub-scanning direction D2 orthogonal to the main scanning direction D1 parallel to the axial direction of the photosensitive drum 21 (see FIG. 1). The light condensed by the cylindrical lens 15 enters the polygon mirror 17. The polygon mirror 17 reflects the incident light as described above while being rotationally driven at a constant angular velocity by a drive source (not shown). The scanning lens 18 converts the movement of the light reflected by the polygon mirror 17 accompanying the rotation of the polygon mirror 17 into a constant speed movement in the main scanning direction D1. The outgoing light reflecting mirror 19 reflects light passing through the scanning lens 18 obliquely upward toward the photosensitive drum 21. The light reflected by the outgoing light reflecting mirror 19 travels to the photosensitive drum 21 through a window of dust-proof glass (not shown) provided on the upper cover 11b.

  The optical scanning device 10 described above scans the circumferential surface of the photosensitive drum 21 in the main scanning direction D1 by the rotation of the polygon mirror 17, and scans in the sub-scanning direction D2 by the rotation of the photosensitive drum 21.

  Next, attachment of the laser diode 12 when the optical scanning device 10 is assembled will be described. In the present embodiment, a mounting jig described below is used for mounting the laser diode 12.

  FIG. 4 is a perspective view showing a mounting jig used for mounting the laser diode, and FIG. 5 is a cross-sectional view of the mounting jig shown in FIG. 4 along the line AA in FIG. FIG. In the perspective view of FIG. 4, the side wall 11c of the housing main body 11a in which the insertion hole 11d of the laser diode 12 is provided is shown in a state where the upper half is cut out for easy understanding of the drawing. The side wall 11c of the housing body 11a is provided with a circular groove 11e that surrounds the fitting hole 11d over the entire circumference. The mounting jig 100 includes a columnar holding portion 101 that holds the laser diode 12 at the tip, and a cylindrical extension portion 102 whose tip edge is inserted into the groove 11e. Furthermore, the mounting jig 100 has a connecting portion 103 that connects the outer periphery of the holding portion 101 opposite to the tip that holds the laser diode 12 and the inner wall surface of the expanding portion 102. The mounting jig 100 corresponds to an embodiment of the mounting jig referred to in the present invention. The circular groove 11e provided on the side wall 11c of the housing body 11a corresponds to an example of the groove according to the present invention, and the columnar holding portion 101 corresponds to an example of the holding portion according to the present invention. The extension unit 102 corresponds to an example of the extension unit referred to in the present invention.

  The cylindrical expansion portion 102 has a first diameter that is slightly larger than the outer diameter of the circular groove 11e and a second diameter that is slightly smaller than the outer diameter of the circular groove 11e. It can be adjusted between. In the present embodiment, the mounting jig 100 is made of metal, and the adjustment of the outer diameter of the expanded portion 102 is performed by expansion due to heating and contraction due to cooling. The housing body 11a is made of resin. That is, the extended portion 102 in the mounting jig 100 is formed of a material having higher rigidity than the material forming the housing body 11a.

  Next, the fitting operation of the laser diode 12 into the fitting hole 11d using the mounting jig 100 will be described with reference to FIGS. FIG. 6 is a diagram illustrating a state before the laser diode is inserted into the insertion hole. FIG. 7 is a diagram showing a state in which the laser diode is being inserted into the insertion hole. FIG. 8 is a view showing a state where the mounting jig is removed after the laser diode is inserted into the insertion hole.

  The laser diode 12 has a generally cylindrical shape, and has an end portion on the opposite side to the light exit opening that is spread like a bowl. As shown in FIG. 6, the inner diameter D of the insertion hole 11 d is narrower than the outer diameter d of the end portion that expands in a bowl shape before the laser diode 12 is inserted. .

  In the operation of fitting the laser diode 12 into the fitting hole 11d, first, the laser diode 12 is held at the tip of the holding portion 101 of the mounting jig 100. At this time, the distal end edge of the cylindrical extension portion 102 is in a state of protruding forward in the fitting direction of the laser diode 12 from the end portion of the laser diode 12 that spreads in a bowl shape. Furthermore, the outer diameter of the cylindrical expansion part 102 is expanded to an outer diameter p larger than the outer diameter P of the circular groove 11e surrounding the fitting hole 11d by heating.

  Next, the laser diode 12 is fitted into the fitting hole 11d, but as described above, the tip edge of the extended portion 102 protrudes forward in the fitting direction from the end portion of the laser diode 12 spreading in a bowl shape. . For this reason, as shown in FIG. 7, at the time of fitting, first, the distal end edge of the extended portion 102 is inserted into the circular groove 11e. At this time, the outer diameter p of the extension portion 102 is larger than the outer diameter P of the groove 11e, and the extension portion 102 of the mounting jig 100 is made of a metal material having higher rigidity than the resin material forming the housing 11. Is formed. As a result, when the distal end edge of the expanded portion 102 is inserted into the groove 11e, a force F is applied to the groove 11e to expand the outer diameter to an outer diameter P ′ substantially equal to the outer diameter p of the expanded portion 102. It will be. Thereby, the space | interval of the outer diameter of the groove | channel 11e, ie, the location which pinched | interposed the insertion hole 11d, is expanded. By expanding the outer diameter of the groove 11e, the inner diameter of the fitting hole 11d is expanded to an inner diameter D 'that is larger than the outer diameter d of the end portion of the laser diode 12 that expands in a bowl shape. The end of the laser diode 12 that is spread like a bowl is fitted into the fitting hole 11d that is expanded in this way.

  After the fitting, as shown in FIG. 8, the outer diameter of the cylindrical expansion portion 102 is smaller than the outer diameter P before the fitting of the laser diode 12 in the circular groove 11e due to cooling. The diameter is reduced to a diameter p ′. As a result, the outer diameter of the groove 11e returns to the outer diameter P before fitting, and the outer diameter of the fitting hole 11d is substantially the same as the outer diameter d of the end portion of the laser diode 12 that expands in a bowl shape. As a result, the laser diode 12 is fixed to the side wall 11c in a state equivalent to being press-fitted into the fitting hole 11d, and then the mounting jig 100 is moved in the direction opposite to the fitting direction. When pulled, the holding portion 101 is separated from the laser diode 12 fixed to the side wall 11c, and the leading edge of the expanded portion 102 having a reduced diameter as described above is removed from the groove 11e. The fitting operation into the fitting hole 11d is completed.

  According to the mounting jig 100 of the present embodiment, the laser diode 12 is fitted into the fitting hole 11d in a state where the fitting hole 11d is expanded as described above. Thereby, when the laser diode 12 is fitted, the load applied to the laser diode 12 is suppressed, and the generation of scraps is also suppressed. That is, according to the mounting jig 100, it is possible to mount the laser diode 12 to the housing 11 while suppressing the load applied to the laser diode 12 and the generation of scraps when the optical scanning device 1 is assembled.

  Further, since the extension portion 102 of the mounting jig 100 of the present embodiment is formed of a metal material having higher rigidity than the resin material forming the housing 11, insertion of the extension portion 102 into the groove 11c The fitting hole 11d is surely expanded.

  Further, the expansion portion 102 of the mounting jig 100 of the present embodiment has an outer diameter that can be expanded and contracted by heating and cooling, that is, when the leading edge is inserted into the groove 11c, the insertion hole 11d. The interval between the parts that can be sandwiched between them is adjustable. As a result, the insertion hole 11d is expanded by insertion of the expanded portion 102 with the expanded diameter into the groove 11c, and extraction from the groove 11c is facilitated by the reduced diameter of the expanded portion 102.

  In the mounting jig 100 of this embodiment, the expansion / contraction of the expansion part 102 is performed by heating and cooling, but the expansion / contraction of the expansion part 102 is not limited to this. The expansion / contraction method of the expansion part 102 may be, for example, a method of reducing the diameter of the expansion part 102 by applying an external force to the outer peripheral surface and expanding the diameter by removing the external force.

  In addition, the mounting jig 100 of the present embodiment includes a holding unit 101 that holds the laser diode 12 and is provided at a distance from the expansion unit 102. Since the space | interval is opened between the expansion part 102 and the holding | maintenance part 101, the holding | maintenance part 101 is hard to receive to the influence of the reaction force at the time of the expansion part 102 expanding the fitting hole 11d. Therefore, according to the mounting jig 100 of the present embodiment, a decrease in the holding force of the laser diode 12 by the holding portion 101 and a displacement of the fitting position due to such a reaction force can be suppressed.

  In addition, in the mounting jig 100 of the present embodiment, the extension portion 102 is provided at a position where it is inserted into the groove 11e prior to the insertion of the laser diode 12 into the insertion hole 11d. As a result, the laser diode 12 is first fitted into the fitting hole 11d after the fitting hole 11d has been expanded in diameter. As a result, the load applied to the laser diode 12 and the generation of scraps when fitted are further reduced.

  Further, in the mounting jig 100 of the present embodiment, the groove 11e has a circular shape that surrounds the fitting hole 11d, and the extended portion 102 has a cylindrical shape, and a tip edge thereof is inserted into the circular groove 11e. Thereby, the expansion part 102 will expand the circular groove | channel 11e uniformly in an outer peripheral direction, and will extend the insertion hole 11d uniformly in an outer peripheral direction by extension. As a result, the contact between the laser diode 12 and the inner surface of the insertion hole 11e is suppressed, so that the load on the laser diode 12 and the generation of scraps are further reduced during the insertion.

  In the present embodiment, a circular groove 11e surrounding the fitting hole 11d is illustrated as an example of the recess according to the present invention. However, the concave portion referred to in the present invention is not limited to such a circular groove, and may be, for example, a plurality of indentations arranged so as to surround the fitting hole 11d. Moreover, as such a some hollow, the some groove | channel etc. which are arrange | positioned on the circumference | surroundings surrounding 11d of insertion holes are mentioned, for example. Further, when such a plurality of grooves are provided as the recesses, the extension portion is different from the cylindrical extension portion 102 in the present embodiment, such as a plurality of claws each inserted into each groove, etc. Become.

In addition, the embodiment described above is merely a representative form of the present invention, and the present invention is not limited to this embodiment. That is, those skilled in the art can implement various modifications in accordance with conventionally known knowledge without departing from the scope of the present invention. Of course, such modifications are included in the scope of the present invention as long as the configuration of the mounting jig of the present invention is provided.

  For example, in the optical scanning device 10 of this embodiment, the light emitted from the laser diode 12 is incident on the polygon mirror 17 through the optical path including the collimating lens 13, the aperture 14, and the cylindrical lens 15. However, the optical path is not limited to this, and may follow an arbitrary path formed by reflection such as a mirror.

Further, for example, the image forming apparatus 1 of this embodiment is a monochrome printer, images forming apparatus is not limited thereto. Images forming apparatus may be a color printer, or as long as it employs an electrophotographic system, a copying machine, a facsimile, or may be a complex machine or the like.

DESCRIPTION OF SYMBOLS 1 Image forming apparatus 10 Optical scanning device 11 Housing 11c Side wall 11d Insertion hole 11e Groove 12 Laser diode 100 Mounting jig 101 Holding part 102 Expansion part

JP 2013-007778 A

Claims (6)

A light source and a housing provided with a wall provided with a fitting hole narrower than the thickness of the light source at the time before the light source is fitted, and the scanning target is scanned with the light emitted from the light source. In the assembly of the optical scanning device for scanning, in the mounting jig that holds the light source and fits into the fitting hole,
The wall of the housing is provided with a recess surrounding the fitting hole,
When the light source is fitted into the fitting hole, an extension portion is provided which is inserted into the concave portion and expands the fitting hole by widening the interval between the portions of the concave portion sandwiching the fitting hole. A mounting jig characterized by that.   The mounting jig according to claim 1, wherein the extension portion is formed of a material having higher rigidity than a material forming the housing.   The mounting jig according to claim 1 or 2, wherein when the extended portion is inserted into the concave portion, the interval between the portions sandwiching the fitting hole is freely adjustable.   The mounting jig according to any one of claims 1 to 3, further comprising a holding portion that is provided with a gap between the extension portion and holds the light source.   5. The extension portion according to claim 1, wherein the extension portion is provided at a position where the extension portion is inserted into the recess prior to the insertion of the light source into the insertion hole. 6. The mounting jig described.   The mounting jig according to any one of claims 1 to 5, wherein the concave portion is a groove disposed on a circumference surrounding the fitting hole.

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