JP2008018700A - Exposure device, led head, and image formation device - Google Patents

Abstract

An operation for attaching an adjustment member can be simplified.
A plurality of light emitting elements, a lens for converging light emitted from each of the light emitting elements, a support member for supporting the light emitting elements and the lens, and an adjusting member for adjusting an interval between the image carrier and the lens. And a holding member 50 that sandwiches the support member and the adjustment member and presses the adjustment member against the support member with a predetermined biasing force. As the holding member 50 is attached to the support member, the adjustment member can be pressed against the support member with a predetermined biasing force, so that the operation for attaching the adjustment member can be simplified.
[Selection] Figure 1

Description

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

  2. Description of the Related Art Conventionally, in an image forming apparatus such as a printer, a copier, a facsimile machine, a multifunction machine, for example, an image forming apparatus as a printer (LED printer) that uses an LED (Light Emitting Diode) head as a writing light source, the LED head is used. The light generated by the LED array chip that is configured is converged by passing through a rod lens array having convergence, and an electrostatic latent image is formed by exposing a photosensitive drum disposed at an imaging position. It has come to be.

Then, the distance between the end surface that emits light of the rod lens array, that is, the distance between the exit end surface and the surface of the photosensitive drum is adjusted by a pin as an adjustment member (see, for example, Patent Document 1).
JP 2003-11414 A

  However, in the conventional printer, in order to adjust the distance between the emission end face and the surface of the photosensitive drum, it is necessary not only to select and attach a pin having an appropriate length, but also to attach the pin. The work is complicated.

  An object of the present invention is to provide an exposure apparatus, an LED head, and an image forming apparatus capable of solving the problems of the conventional printer and simplifying the work for attaching the adjustment member.

  Therefore, in the exposure apparatus of the present invention, a plurality of light emitting elements, a lens for converging light emitted from each light emitting element, a support member for supporting the light emitting element and the lens, an image carrier and a lens, An adjustment member that adjusts the distance between the support member and the adjustment member, and a holding member that presses the adjustment member against the support member with a predetermined urging force.

  According to the present invention, in the exposure apparatus, a plurality of light emitting elements, a lens that converges light emitted from each light emitting element, a support member that supports the light emitting element and the lens, an image carrier, and a lens, An adjustment member that adjusts the distance between the support member and the adjustment member, and a holding member that presses the adjustment member against the support member with a predetermined urging force.

  In this case, as the holding member is attached to the support member, the adjustment member can be pressed against the support member with a predetermined biasing force, so that the work for attaching the adjustment member can be simplified. it can.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In this case, a printer as an image forming apparatus will be described.

  FIG. 2 is a schematic view of the printer according to the first embodiment of the present invention.

  As shown in the figure, in the printer 11, image forming units 12Bk, 12Y, 12M, and 12C constituting four independent image forming units are arranged from the insertion side to the discharge side of a sheet as a recording medium. The image forming units 12Bk, 12Y, 12M, and 12C form images of black, yellow, magenta, and cyan. In addition to paper, OHP paper, envelopes, copy paper, special paper, and the like can be used as the recording medium.

  Each of the image forming units 12Bk, 12Y, 12M, and 12C has a uniform and uniform surface of the photosensitive drums 13Bk, 13Y, 13M, and 13C as image carriers and the photosensitive drums 13Bk, 13Y, 13M, and 13C. A toner (not shown) as a developer is attached to the electrostatic latent images formed on the surfaces of the charging rollers 14Bk, 14Y, 14M, and 14C and the photosensitive drums 13Bk, 13Y, 13M, and 13C as charging devices for charging the toner; It has developing rollers 16Bk, 16Y, 16M, 16C and the like as developer carrying members that form toner images of respective colors that are visible images. Further, toner supply rollers 18Bk, 18Y, 18M, and 18C as developer supply members are disposed in pressure contact with the developing rollers 16Bk, 16Y, 16M, and 16C, and the toner supply rollers 18Bk, 18Y, 18M, and 18C are 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 brought into pressure contact with the developing rollers 16Bk, 16Y, 16M, and 16C. The toner supplied from the toner supply rollers 18Bk, 18Y, 18M, and 18C is thinned.

  Further, above the photosensitive drums 13Bk, 13Y, 13M, and 13C in the image forming units 12Bk, 12Y, 12M, and 12C, LED heads 15Bk, 15Y, 15M, and 15C as exposure devices are provided on the photosensitive drums 13Bk, 13Y, and 13C, respectively. The LED heads 15Bk, 15Y, 15M, and 15C are arranged to face the 13M and 13C, respectively, and expose the photosensitive drums 13Bk, 13Y, 13M, and 13C according to the image data of each color to form an electrostatic latent image. A transfer unit is disposed below the photosensitive drums 13Bk, 13Y, 13M, and 13C in the image forming units 12Bk, 12Y, 12M, and 12C. The transfer unit is disposed to be opposed to each of the photosensitive drums 13Bk, 13Y, 13M, and 13C via the conveyance belt 21 and a conveyance belt 21 that is disposed so as to freely travel in the direction of arrow e. Transfer rollers 17Bk, 17Y, 17M, and 17C are provided as transfer devices that charge the paper to the opposite polarity to the toner and transfer the toner images of the respective colors onto the paper.

  A paper feed mechanism for supplying paper to the transport path is disposed below the printer 11. The paper feed mechanism includes a hopping roller 22, a registration roller 23, a paper storage cassette 24 as a medium storage unit, A paper color measurement unit 25 that measures the color of the paper in the paper storage cassette 24 is provided. 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 sent from the registration roller 23 to the conveying belt 21 and is conveyed as the conveying belt 21 travels. In each of the image forming units 12Bk, 12Y, 12M, and 12C, the transfer roller 17Bk, The toner images of the respective colors are transferred to the paper by 17Y, 17M, and 17C, and color toner images are formed. The paper on which the color toner image is formed is sent to the fixing device 28, where the color toner image is fixed on the paper and a color image is formed.

  Next, the relationship between the photosensitive drums 13Bk, 13Y, 13M, and 13C having the above configuration and the LED heads 15Bk, 15Y, 15M, and 15C will be described. Since the relationship between the photosensitive drums 13Bk, 13Y, 13M, and 13C and the LED heads 15Bk, 15Y, 15M, and 15C in the image forming units 12Bk, 12Y, 12M, and 12C is the same, the photosensitive drum 13Bk. Only the relationship between the LED head 15Bk and the LED head 15Bk will be described.

  FIG. 3 is a longitudinal sectional view showing the arrangement state of the LED head according to the first embodiment of the present invention, and FIG. 4 is a transverse sectional view showing the arrangement state of the LED head according to the first embodiment of the present invention. is there.

  In the figure, 13Bk is a photosensitive drum, 15Bk is an LED head, 31 is arranged facing the photosensitive drum 13Bk, and is an LED array chip comprising LEDs as a plurality of light emitting elements, and 32 is the LED array chip and the photosensitive member. A rod lens array disposed between the drum 13Bk and having convergence and as a lens for converging light emitted from each LED, 33 is an LED array chip 31 composed of a plurality of chips, and the LED array chip A substrate on which a driver IC (not shown) for controlling 31 is mounted, 34 is a lens array holder as a support member to which the rod lens array 32 is fixed and the substrate 33 is attached, and the lens array holder 34 is This is a die-cast product manufactured by casting aluminum material into a mold.

  After the lens array 32 is fixed to the lens array holder 34, the gap between the lens array holder 34 and the lens array holder 34 is sealed with a silicon agent 41 in order to prevent light and foreign matter from entering.

  Reference numeral 35 denotes a base, and 38 denotes a clamp for pressing the substrate 33 against the substrate contact surface SI of the lens array holder 34 via the base 35. As shown in FIG. 3, the LED head 15Bk having the above-described configuration is disposed to face the photosensitive drum 13Bk.

By the way, in order to image light accurately on the photosensitive drum 13Bk, the distance between the surface of the LED array chip 31 and the end face on which the light of the lens array 32 is incident, that is, the incident end face is set to L1. When the distance between the exit end face of the lens array 32 and the surface of the photosensitive drum Bk (the interval between the lens array 32 and the photosensitive drum 13Bk) is L2,
L1 = L2
It is necessary to adjust the distance L2 so that

  For this purpose, eccentric cam mechanisms 42 and 43 as adjustment mechanisms are disposed in the vicinity of the end of the lens array holder 34 in the length direction, and are arranged on the surfaces of the eccentric cam mechanisms 42 and 43 and the respective photosensitive drums 13. The provided spacers 38a and 38b are brought into contact with each other.

  Note that coil springs 37 as urging members are disposed at both ends of the base 35, and each of the coil springs 37 urges the LED head 15 toward the photosensitive drum 13, and spacers 38a and 38b. The eccentric cam mechanisms 42 and 43 are brought into contact with the contact surface (any height at which L1 = L2), and the distance L2 is kept constant.

  FIG. 5 is a first perspective view showing the eccentric cam mechanism in the first embodiment of the present invention, FIG. 6 is a first perspective view showing the eccentric cam in the first embodiment of the present invention, and FIG. FIG. 8 is a second perspective view showing the eccentric cam in the first embodiment of the present invention, and FIG. 8 is a second perspective view showing the eccentric cam in the first embodiment of the present invention.

  As shown in the figure, the eccentric cam mechanisms 42 and 43 include eccentric cams 42a and 43a as adjustment members for adjusting the distance L2, and a plate-like holding member 50, and the eccentric cam 42a includes a shaft portion 42b. And cam portions 42c formed integrally at both ends of the shaft portion 42b. Each of the cam portions 42c is formed so as to protrude outward in the radial direction of the shaft portion 42b on an axis that is eccentric by a predetermined amount with respect to the axis H of the shaft portion 42b. Larger than the outer diameter. The eccentric cam 43a includes a shaft portion 43b formed at both ends, and a cam portion 43c formed integrally between the shaft portions 43b. The cam portion 43c is formed to protrude outward in the radial direction of the shaft portion 43b on an axis that is eccentric by a predetermined amount with respect to the axis I of each shaft portion 43b. Larger than the outer diameter.

  The holding member 50 is fixed to the lens array holder 34 in a state in which the end portion 50a of the main body 50c of the holding member 50 is abutted against the protrusion 34a formed on the lens array holder 34. As it is attached, the eccentric cams 42a and 43a are pressed against the lens array holder 34 with a predetermined urging force. Also, the finger portions 50b as the two pressing portions of the holding member 50 press the shaft portions 42b and 43b of the eccentric cams 42a and 43a to the lens array holder 34 with a predetermined biasing force.

  The cam portions 42c and 43c of the eccentric cams 42a and 43a have a predetermined shape so that the eccentric cams 42a and 43a can be rotated by an operating tool, in this embodiment, by a driver (not shown). In the present embodiment, cross-shaped grooves 42d and 43d are formed on the axes H and I of the shaft portions 42b and 43b. Therefore, the operator can rotate the eccentric cams 42a and 43a around the axes H and I by pressing the tip of the driver against the grooves 42d and 43d.

  As a result, according to the rotation state of the eccentric cams 42a and 43a, the distance between the position of each axis H and I and the position where the cam portions 42c and 43c abut the spacers 38a and 38b changes. The distance L2 can be adjusted.

  FIG. 1 is a first exploded perspective view showing an eccentric cam mechanism in the first embodiment of the present invention. FIG. 9 is a second exploded perspective view showing an eccentric cam mechanism in the first embodiment of the present invention. FIG. 10 is a third exploded perspective view showing the eccentric cam mechanism in the first embodiment of the present invention, FIG. 11 is a side view of the holding member in the first embodiment of the present invention, and FIG. The figure which shows the attachment method of the holding member in 1st Embodiment, FIG. 13 is 1st figure which shows the function of the holding member in 1st Embodiment of this invention, FIG. 14 is 1st implementation of this invention It is a 2nd figure which shows the function of the holding member in this form.

  In order to attach the eccentric cams 42a and 43a to the lens array holder 34, a holding member 50 is provided. Each holding member 50 has a substantially “H” shape, a main body 50c that abuts on an upper surface 34c as a first surface of the lens array holder 34, and a front (one side) from one edge of the main body 50c. Two fingers 50b formed projecting toward the other side of the body 50c, and the second fingers formed projecting rearward (opposite direction) from the other edge of the main body 50c. Between the two finger portions 50g as the attachment portions and the respective finger portions 50g, and is sandwiched by protruding downward from the other edge of the main body 50c and further bending forward. One arm part 50d as a part is provided. Each finger part 50b has a “heavy” shape.

  The holding member 50 is formed of an elastic material, and is attached to the lens array holder 34, so that each of the finger portions 50b surrounds the shaft portions 42b and 43b, and the eccentric cams 42a and 43a are attached to the lens. Press against the array holder 34.

  Further, as shown in FIGS. 9 and 10, the lens array holder 34 is formed with a square hole 34b as a through portion for mounting each holding member 50, and the square hole 34b is shown in FIG. It has such a cross-sectional shape and is formed through the lens array holder 34. The square hole 34b is formed by a die casting mold.

  Further, the lens array holder 34 is formed with a groove 34m having a "U" shape for receiving the eccentric cam 42a and a groove 34n having a "V" shape for receiving the eccentric cam 43a. Is done.

  The holding member 50 has a main body 50c that contacts the upper surface 34c of the lens array holder 34 and an arm portion 50d. The width Wc of the arm portion 50d in the Z direction (the width direction of the lens array holder 34) is an angle. The width Wr in the Z direction of the hole 34b is slightly narrower, and the width Wd in the X direction (the height direction of the lens array holder 34) of the arm portion 50d is slightly narrower than the width Ws in the X direction of the square hole 34b. .

  The arm portion 50d is formed with a contact portion 50e that contacts a lower surface 34d as the second surface of the lens array holder 34 so as to protrude toward the lower surface 34d, and the holding member 50 is attached to the lens array. A locking portion for locking the holder 34 is configured. As the holding member 50 is attached to the lens array holder 34, the contact portion 50e is placed in the vicinity of the axes H and I of the eccentric cam mechanisms 42 and 43. As shown in FIG. 11, when the arm portion 50d is not attached to the lens array holder 34, a distance L3 between the main body 50c and the contact portion 50e is a corner formed on the lens array holder 34. It is set to be shorter than the depth t of the hole 34b. In addition, by deforming the arm portion 50d in the direction of the arrow, the space between the main body 50c and the contact portion 50e can be increased.

  Next, the operation of the eccentric cam mechanisms 42 and 43 having the above configuration will be described.

  As shown in FIG. 12, when the arm portion 50d formed on the holding member 50 is inserted into the square hole 34b and the holding member 50 is attached to the lens array holder 34, the arm portion 50d is rotatably arranged on the lens array holder 34. The shaft portions 42b and 43b of the eccentric cam mechanisms 42 and 43 are held by a finger portion 50b as a first finger portion.

  Subsequently, when the holding member 50 is moved in the direction of arrow A, the abutting portion 50e of the arm portion 50d abuts on the lower surface 34d of the lens array holder 34 and is spread, and the distal end portion 50f of the arm portion 50d becomes the lens array holder. The end portion 50a of the holding member 50 passes over the projection portion 34a of the rod lens array holder 34 and is brought into contact with the end surface of the projection portion 34a almost simultaneously with the side surface 34e in the vicinity of the square hole 34b of 34. As a result, the holding member 50 is positioned in the X direction by the side surfaces 34e and the end surfaces of the protrusions 34a. Further, since the width Wc of the arm portion 50d is slightly narrower than the width Wr of the square hole 34b, the holding member 50 is positioned in the Z direction.

  Further, in a state where the holding member 50 is not attached to the lens array holder 34, the distance L3 is shorter than the depth t of the square hole 34b, and the holding member 50 has elasticity. Due to the restoring force, the holding member 50 is pressed against and held by the lens array holder 34, and is positioned in the Y direction (the height direction of the lens array holder 34).

  When the holding member 50 is attached to the lens array holder 34, as shown in FIG. 13, when the holding member 50 receives a reaction force upward from the lens array holder 34 at a point Pa, The point Pa is the main point of the lever principle. Then, the holding member 50 presses the lens array holder 34 downward with a predetermined urging force at a point Pb that contacts the shaft portion 43b. At this time, the point Pb becomes an action point.

  In this case, since the shaft portion 43b and the lens array holder 34 are sandwiched between the finger portion 50b and the contact portion 50e, the eccentric cam 43a can be reliably fixed to the lens array holder 34.

  On the other hand, as shown in FIG. 14, when the holding member 50 receives a reaction force upward from the shaft portion 43b at the point Pb, the point Pb becomes the power point of the lever principle. The holding member 50 presses the lens array holder 34 downward with a predetermined biasing force at a point Pa that contacts the lens array holder 34. As a result, the holding member 50 can be easily fixed to the lens array holder 34 without using a special fixing tool (for example, a screw).

  Further, the end 50 a of the holding member 50 is engaged with the protrusion 34 a of the lens array holder 34, so that the holding member 50 can be prevented from moving due to vibration or the like and coming off from the lens array holder 34.

  As described above, in the present embodiment, the eccentric cams 43a and 43b can be attached to the lens array holder 34 only by attaching the holding member 50 to the lens array holder 34. Therefore, the eccentric cams 43a and 43b are attached to the lens array holder 34. The work for attaching to 34 can be simplified.

  Further, since the contact portion 50e is disposed in the vicinity of the axes H and I of the eccentric cam mechanisms 42 and 43, the axes H and I are urged in a substantially vertical direction. Therefore, the eccentric cams 42a and 43a can be prevented from rotating as the holding member 50 is attached to the lens array holder 34.

  Further, since the holding member 50 is positioned by bringing the distal end portion 50f of the arm portion 50d into contact with the side surface 34e of the square hole 34b, the holding member 50 is not attached and fixed obliquely. Therefore, the holding member 50 can be prevented from interfering with other members, and the quality of the LED head 15Bk can be stabilized.

  By the way, in the first embodiment, after the arm portion 50d formed in the holding member 50 is inserted into the square hole 34b, the arm portion 50d is pressed against the lens array holder 34 by moving the holding member 50. However, it is necessary to make the square hole 34b larger by that amount. In that case, foreign matter such as toner is likely to enter the lens array holder 34 through the square holes 34b.

  In order to reduce the size of the square hole 34b, it is conceivable to reduce the size of the holding member 50 and shorten the finger portion 50g. However, when the finger portion 50g is shortened, the finger portion 50g is in contact with the protrusion 34a. Since the elastic force of the finger part 50a increases, the pressing force required when the arm part 50d is inserted into the square hole 34b and the sliding force required when the holding member 50 is moved are increased. As a result, the assemblability deteriorates.

  Therefore, a second embodiment of the present invention will be described in which the square hole 34b is made as small as possible and the assembling property is not lowered even if the holding member 50 is downsized. In addition, about the thing which has the same structure as 1st Embodiment, the same code | symbol is provided and the effect of the same embodiment is used about the effect of the invention by having the same structure.

  FIG. 15 is a first exploded perspective view showing an eccentric cam mechanism in the second embodiment of the present invention. FIG. 16 is a second exploded perspective view showing the eccentric cam mechanism in the second embodiment of the present invention. FIG. 17 is a third exploded perspective view showing the eccentric cam mechanism in the second embodiment of the present invention, FIG. 18 is a side view of the holding member in the second embodiment of the present invention, and FIG. It is a figure which shows the attachment method of the holding member in 2nd Embodiment.

  In order to attach the eccentric cams 42a and 43a to the lens array holder 34, a holding member 60 is provided. Each holding member 60 has a substantially “H” shape, a main body 60c that abuts the upper surface 34c of the lens array holder 34, and one edge of the main body 60c from the front (in one direction). Two finger portions 60b formed to protrude, two finger portions 60g as attachment portions formed to protrude rearward (opposite direction) from the other edge of the main body 60c, and the Between each finger part 60g, it has one arm part 60d as a clamping part formed by projecting downward from the other edge part of the main body 60c, further reversing and bending upward. Each of the finger portions 60b has a “heavy” shape.

  The holding member 60 is formed of an elastic material, and the eccentric cams 42a and 43a are attached to the lens array holder 34 while the fingers 60b surround the shafts 42b and 43b. Press against the array holder 34.

  In this case, as shown in FIGS. 16 and 17, the lens array holder 34 is formed with square holes 34f as attachment portions for mounting the holding members 60. The square holes 34f are shown in FIG. The lens array holder 34 is formed so as to penetrate the lens array holder 34. The square hole 34f is formed by a die casting mold.

  The holding member 60 has a main body 60c that contacts the upper surface 34c of the lens array holder 34 and an arm portion 60d. The width Wa of the arm portion 60d in the Z direction (the width direction of the lens array holder 34) is an angle. The width Wp in the Z direction of the hole 34f is slightly narrower, and the width Wb in the X direction (the length direction of the lens array holder 34) of the arm portion 50d is slightly wider than the width Wq in the X direction of the square hole 34f. .

  As shown in FIG. 18, the distance L4 between the tip 60e of the arm 60d and the main body 60c is set slightly longer than the depth t of the square hole 34f, and the tip 60e It has elasticity in the direction of the arrow indicated by 18 and is disposed in the vicinity of the axes H and I of the eccentric cam mechanisms 42 and 43.

  Next, the operation of the eccentric cam mechanisms 42 and 43 having the above configuration will be described.

  As shown in FIG. 19, when the arm portion 60d formed on the holding member 60 is inserted into the square hole 34f (FIG. 9) and the holding member 60 is attached to the lens array holder 34, the lens array holder 34 is rotatable. The shaft portions 42b and 43b of the eccentric cam mechanisms 42 and 43 disposed in the are held by the finger portions 60b.

  At this time, the width Wb of the arm portion 60d is set wider than the width Wq of the square hole 34f. However, since the arm portion 60d has elasticity, the width Wq is substantially the same as the width Wq of the square hole 34f. After the end portion 60e is inserted through the square hole 34f and passes through the square hole 34f, the width Wb of the original end portion 60e is restored by elasticity and comes into contact with the side surface 34e in the vicinity of the square hole 34f. At almost the same time, the end 60a of the finger 60g of the holding member 60 passes over the protrusion 34a of the rod lens array holder 34 and is brought into contact with the end surface of the protrusion 34a. As a result, the holding member 60 is positioned in the X direction by the side surfaces 34e and the end surfaces of the protrusions 34a. Further, since the width Wa of the arm portion 60d is set slightly narrower than the width Wp of the square hole 34f, the holding member 60 is positioned in the Z direction.

  Since the finger part 60b formed on the holding member 60 presses the shaft parts 42b and 43b of the eccentric cams 42a and 43a against the lens array holder 34, the holding member 60 does not move when the rod lens array holder 34 is attached. The reaction force of the portion 60b tries to rotate in the direction of the arrow shown in FIG. 19, but the tip portion 60e of the arm portion 60d hits the lower surface 34d near the square hole 34f and is held and fixed with a pressure contact force. .

  As described above, in the present embodiment, the eccentric cams 43a and 43b can be attached to the lens array holder 34 only by attaching the holding member 60 to the lens array holder 34. Therefore, the eccentric cams 43a and 43b are attached to the lens array holder 34. The work for attaching to 34 can be simplified.

  Further, since the tip end portion 60e is disposed in the vicinity of the axes H and I of the eccentric cam mechanisms 42 and 43, the axes H and I are biased in a substantially vertical direction. Accordingly, it is possible to prevent the eccentric cams 42a and 43b from rotating as the holding member 60 is attached to the lens array holder 34.

  In the present embodiment, since the holding member 60 can be attached to the lens array holder 34 simply by being inserted into the lens array holder 34, the square hole 34f can be formed small, and the holding member 60 is further reduced. Even when the arm portion 60d is reduced in size, when the arm portion 60d is inserted into the square hole 34f, the end portion 60a of the finger portion 60g of the holding member 60 can be assembled without coming into contact with the protruding portion 34a, thereby improving the assemblability. be able to.

  The present invention is not limited to the above embodiments, and various modifications can be made based on the gist of the present invention, and they are not excluded from the scope of the present invention.

It is a 1st exploded perspective view showing an eccentric cam mechanism in a 1st embodiment of the present invention. 1 is a schematic diagram of a printer according to a first embodiment of the present invention. It is a longitudinal cross-sectional view which shows the arrangement | positioning state of the LED head in the 1st Embodiment of this invention. It is a cross-sectional view which shows the arrangement | positioning state of the LED head in the 1st Embodiment of this invention. It is a 1st perspective view which shows the eccentric cam mechanism in the 1st Embodiment of this invention. It is a 1st perspective view which shows the eccentric cam in the 1st Embodiment of this invention. It is a 2nd perspective view which shows the eccentric cam mechanism in the 1st Embodiment of this invention. It is a 2nd perspective view which shows the eccentric cam in the 1st Embodiment of this invention. It is a 2nd disassembled perspective view which shows the eccentric cam mechanism in the 1st Embodiment of this invention. It is a 3rd disassembled perspective view which shows the eccentric cam mechanism in the 1st Embodiment of this invention. It is a side view of the holding member in the 1st Embodiment of this invention. It is a figure which shows the attachment method of the holding member in the 1st Embodiment of this invention. It is a 1st figure which shows the function of the holding member in the 1st Embodiment of this invention. It is a 2nd figure which shows the function of the holding member in the 1st Embodiment of this invention. It is a 1st disassembled perspective view which shows the eccentric cam mechanism in the 2nd Embodiment of this invention. It is a 2nd disassembled perspective view which shows the eccentric cam mechanism in the 2nd Embodiment of this invention. It is a 3rd disassembled perspective view which shows the eccentric cam mechanism in the 2nd Embodiment of this invention. It is a side view of the holding member in the 2nd Embodiment of this invention. It is a figure which shows the attachment method of the holding member in the 2nd Embodiment of this invention.

Explanation of symbols

13Bk, 13Y, 13M, 13C Photosensitive drums 15Bk, 15Y, 15M, 15C LED head 31 LED array chip 32 Rod lens array 34 Lens array holder 42a, 43a Eccentric cam 50, 60 Holding member

Claims (10)

(A) a plurality of light emitting elements;
(B) a lens that converges the light emitted from each of the light emitting elements;
(C) a support member that supports the light emitting element and the lens;
(D) an adjustment member that adjusts the distance between the image carrier and the lens;
(E) An exposure apparatus comprising: a holding member that sandwiches the support member and the adjustment member and presses the adjustment member against the support member with a predetermined biasing force. (A) The support member includes a first surface for pressing the adjustment member, a second surface facing the first surface, and a through hole connecting the first surface and the second surface. And having a part
(B) The holding member includes a first finger for pressing the adjustment member against the first surface, and a second for engaging the adjustment member with a protrusion formed on the first surface. The exposure apparatus according to claim 1, further comprising: a holding portion that is formed between the first finger portion and the first and second finger portions and is inserted through the penetrating portion to engage with the second surface. (A) The adjustment member includes a shaft portion and a cam portion,
(B) The exposure apparatus according to claim 2, wherein the cam portion is formed on an axis decentered by a predetermined amount with respect to the axis of the shaft portion.   The exposure apparatus according to claim 3, wherein the first finger part presses the shaft part.   An image forming apparatus on which the exposure apparatus according to claim 1 is mounted. (A) a plurality of LEDs;
(B) a lens that converges the light emitted from each LED;
(C) a support member that supports the LED and the lens;
(D) an adjustment member that adjusts the distance between the image carrier and the lens;
(E) An LED head comprising: a holding member that sandwiches the support member and the adjustment member and presses the adjustment member against the support member with a predetermined biasing force. (A) The support member includes a first surface for pressing the adjustment member, a second surface facing the first surface, and a through hole connecting the first surface and the second surface. And having a part
(B) The holding member includes a first finger for pressing the adjustment member against the first surface, and a second for engaging the adjustment member with a protrusion formed on the first surface. The LED head according to claim 6, further comprising: a nipping portion formed between the first finger portion and the first and second finger portions, the pinching portion being inserted through the penetrating portion and engaged with the second surface. (A) The adjustment member includes a shaft portion and a cam portion,
(B) The LED head according to claim 7, wherein the cam portion is formed on an axis decentered by a predetermined amount with respect to the axis of the shaft portion.   The LED head according to claim 8, wherein the first finger portion presses the shaft portion. An image forming apparatus on which the LED head according to any one of claims 6 to 9 is mounted.

Images