CN214067584U - Exposure device and image forming apparatus - Google Patents

Abstract

The utility model provides an exposure device and image forming apparatus. The exposure apparatus of the embodiment includes: a print head; a lifting part for supporting and lifting the bracket provided with the printing head; a first sliding part which moves along the depth direction of the exposure device in linkage with the lifting of the bracket; a force application member which is provided at one end of the first slide portion and applies a force to the first slide portion in the depth direction; a second sliding part which is connected with the first sliding part and moves along with the movement of the first sliding part, wherein a protrusion is formed on the outer peripheral surface of the second sliding part; and a guide portion which is fitted around the outer periphery of the second sliding portion and has a guide groove for guiding the protrusion, wherein the protrusion abuts against a groove surface of the guide groove when guided to one end by the guide groove, and the protrusion abuts against an abutment wall of the guide portion, which is orthogonal to the depth direction, when guided to the other end by the guide groove. Through the utility model discloses, can prevent that guide portion from warping and can make and beat printer head and keep in the position of regulation.

Description

Exposure device and image forming apparatus

Technical Field

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

Background

Conventionally, an image forming apparatus such as an electrophotographic apparatus has an exposure apparatus using, for example, a print head. In such an exposure apparatus, it is necessary to position the print head and the photosensitive drum. As such a positioning technique, a technique is known in which a print head is reciprocated between an abutment position and a separation position by an elevating unit. When the print head is at the abutting position, the print head abuts against the photosensitive drum of the image forming unit to perform printing, and when the print head is at the separating position, the image forming unit can be removed or the print head can be cleaned. In this case, the exposure apparatus performs the function of raising and lowering the print head by moving the first slide portion in the depth direction of the exposure apparatus in conjunction with the raising and lowering of the carriage supporting the print head. In order to hold the print head at the abutment position, it is necessary to provide a biasing member for pressurizing the first slide portion at one end of the first slide portion, and the biasing member applies a load to the first slide portion to hold the first slide portion at a predetermined position.

However, when the first slide portion is loaded by the biasing member during the print head up-down operation, the groove of the guide portion for guiding the print head up-down movement is likely to be deformed, and the print head is likely to be displaced from the predetermined contact position and separation position.

SUMMERY OF THE UTILITY MODEL

The utility model provides an exposure device and image forming device that prevent that guide portion warp and make and beat printer head and keep in the position of regulation.

The exposure apparatus of the embodiment includes: a print head that exposes the photosensitive drum and forms an electrostatic latent image on the photosensitive drum; a lifting part which supports and lifts a support on which the print head is mounted; a first sliding unit that moves in the depth direction of the exposure device in conjunction with the lifting and lowering of the carriage; a biasing member that is provided at one end of the first slide portion and biases the first slide portion in the depth direction; a second sliding portion connected to the first sliding portion and moving along with the movement of the first sliding portion, the second sliding portion having a protrusion formed on an outer circumferential surface thereof; and a guide portion that is fitted around an outer periphery of the second sliding portion and has a guide groove formed therein for guiding the projection, wherein the projection abuts against a groove surface of the guide groove when guided to one end by the guide groove, and the projection abuts against an abutting wall of the guide portion orthogonal to the depth direction when guided to the other end by the guide groove.

An image forming apparatus of another embodiment includes: an original conveying portion that conveys an original to be transferred; a scanner section that reads the original to generate image data of the original; an image forming unit that forms a toner image according to the image data; a fixing section that fixes the toner image on the recording medium; and an exposure device that irradiates the image forming unit with exposure light, the exposure device including: a print head that exposes the photosensitive drum and forms an electrostatic latent image on the photosensitive drum; a lifting part which supports and lifts a support on which the print head is mounted; a first sliding unit that moves in the depth direction of the exposure device in conjunction with the lifting and lowering of the carriage; a biasing member that is provided at one end of the first slide portion and biases the first slide portion in the depth direction; a second sliding portion connected to the first sliding portion and moving along with the movement of the first sliding portion, the second sliding portion having a protrusion formed on an outer circumferential surface thereof; and a guide portion that is fitted around an outer periphery of the second sliding portion and has a guide groove formed therein for guiding the projection, wherein the projection abuts against a groove surface of the guide groove when guided to one end by the guide groove, and the projection abuts against an abutting wall of the guide portion orthogonal to the depth direction when guided to the other end by the guide groove.

Through the utility model discloses, can prevent that guide portion from warping and can make and beat printer head and keep in the position of regulation.

Drawings

FIG. 1 is a schematic view of an image forming apparatus according to the present invention;

fig. 2 is a schematic structural view of an exposure apparatus according to the present invention;

fig. 3 is a schematic plan view of an end portion of the exposure apparatus according to the present invention;

fig. 4 is a schematic perspective view of an end portion of the exposure apparatus of the present invention;

fig. 5 is a schematic perspective view of the exposure apparatus according to the present invention with the print head in the abutting position;

fig. 6 is a schematic perspective view of the exposure apparatus according to the present invention with the print head in a separated position;

FIG. 7 is a schematic partial top view of a prior art exposure apparatus with the print head in a disengaged position;

fig. 8 is a perspective view of a guide portion in the exposure apparatus according to the present invention;

fig. 9 is a schematic perspective view of the exposure apparatus according to the present invention when the print head is at the separated position.

Detailed Description

Hereinafter, an exposure apparatus and an image forming apparatus according to an embodiment will be described with reference to the drawings. In the drawings, the same components are denoted by the same reference numerals.

For convenience of explanation, coordinate axes are shown in the drawings. The X-axis direction is a lateral direction (hereinafter also referred to as a horizontal direction) of the exposure device and the image forming apparatus. The Y-axis direction is a longitudinal direction (hereinafter also referred to as a vertical direction) of the exposure device and the image forming apparatus. The Z-axis direction is a depth direction of the exposure device and the image forming apparatus. The direction of the exposure device and the image forming apparatus along the X-axis arrow is the right side, the direction of the exposure device and the image forming apparatus along the Y-axis arrow is the upper side, and the direction of the exposure device and the image forming apparatus along the Z-axis arrow (toward the back side in fig. 1) is the rear side, and the left side, the lower side, and the front side are opposite to the above. The X, Y and Z directions are orthogonal to each other. In the drawings, the structure is shown enlarged, reduced, or omitted as appropriate for convenience of explanation.

Fig. 1 is a schematic configuration diagram of an image forming apparatus 1 according to the present invention.

As shown in fig. 1, the image forming apparatus 1 of the present embodiment is, for example, a multifunction peripheral (MFP), a printer, a copier, or the like. The image forming apparatus 1 forms an image on a recording medium based on image data read on a document. Next, a case where the image forming apparatus 1 is a multifunction peripheral will be described.

The image forming apparatus 1 has a main body 11, and the main body 11 is a housing as a frame of the image forming apparatus 1. An image reading portion 12 is provided on an upper portion of the main body 11, and the image reading portion 12 is used to read an original to generate image data of the original. The image reading portion 12 is composed of a document conveying portion 13 and a scanner portion 14.

A scanner unit 14 is provided below the document conveying unit 13. The original conveying portion 13 conveys an original to be transferred to the scanner portion 14. The scanner section 14 has an optical mechanism 15, and the scanner section 14 reads the original to be transferred conveyed by the original conveying section 13 or the original to be transferred placed directly on a platen glass of the scanner section 14 through the optical mechanism 15 to generate image data of the original.

The optical mechanism 15 moves in the lateral direction (X-axis direction) along the platen glass when reading an image of an original directly placed on the platen glass of the scanner section 14. The optical mechanism 15 reads an original image on one original page line by line. When reading an image of a document conveyed by the document conveying portion 13, the optical mechanism 15 reads the conveyed document at a fixed position shown in fig. 1.

An operation display unit 16 is provided in front of the scanner unit 14 (in the (-Z direction) and above the main body 11 (in the (+ Y direction)). The operation display unit 16 has a function of receiving an operation by an operator and displaying a state of the image forming apparatus 1. The operation display unit 16 is, for example, a touch-enabled liquid crystal display.

The main body 11 has a transfer portion 17 at the center in the longitudinal direction (Y-axis direction). The main body 11 has a plurality of paper feed cassettes 18 below (-Y direction) for feeding a recording medium to the transfer unit 17. The plurality of paper feed cassettes have substantially the same configuration, and are arranged so as to overlap one another in the upper (+ Y direction) and the lower (-Y direction), for example, two paper feed cassettes are provided in the present embodiment.

The sheet feeding cassette 18 has a sheet feeding mechanism 19. The paper feed mechanism 19 takes out the recording media P one by one from the paper feed cassette 18 and conveys the recording media P to a conveyance path. For example, the paper feeding mechanism 19 may include a pickup roller, a separation roller, and a paper feeding roller.

The transfer portion 17 has a plurality of image forming units 51 that form toner images using different color toners (e.g., yellow, magenta, cyan, black, etc.), a plurality of exposure devices 3, and an intermediate transfer belt 53. The image forming unit 51 forms a toner image from image data read by the scanner section 14 or image data made by a personal computer or the like using toner. The image forming unit 51 converts image data into color signals of respective colors, and controls the plurality of exposure devices 3 in accordance with the color signals of the respective colors.

The configuration of the transfer section 17 is not limited to this, and the transfer section may have two or three image forming units, or the transfer section may have five or more image forming units.

The respective image forming units 51 are arranged in parallel from the left side (-X direction) toward the right side (+ X direction) below the intermediate transfer belt 53 (-Y direction). Each image forming unit 51 is mounted in the image forming apparatus 1 in a replaceable manner. For example, the image forming unit 51 is mounted in the image forming apparatus 1 and dismounted from the image forming apparatus 1 by being inserted and removed from the front side (+ Z direction) in the depth direction (Z axis direction) of the image forming apparatus 1.

The plurality of exposure devices 3 irradiate exposure light L to each image forming unit 51. The plurality of exposure devices 3 may generate laser scanning beams as exposure light. The plurality of exposure devices 3 may be configured to include a solid-state scanning element such as a light-emitting diode that generates exposure light.

The structures of the respective image forming units 51 are the same as each other except that the colors of the toners are different. Examples of the toner include a decolorable toner which can be decolored (invisible) by an external stimulus (e.g., temperature, light having a specific wavelength, or pressure), and a normal non-decolorable toner. A toner that is decolored by temperature decolors when it reaches a specific decoloring temperature or higher, and develops color when it is equal to or lower than a specific restoration temperature.

Each of the image forming units 51 has a photosensitive drum 56 as an image carrier. The photosensitive drum 56 has a photosensitive body (e.g., an organic photoconductor) on an outer circumferential surface.

Around the photosensitive drum 56, the image forming unit 51 is provided with a charger, a developer, a primary transfer roller, a drum cleaner, and the like in the rotational direction. The charger uniformly charges the surface of the photosensitive drum 56. The plurality of exposure devices 3 generate exposure light L modulated according to image data. The exposure light L exposes the surface of the photosensitive drum 56. The potential of the area on the photosensitive drum 56 irradiated with light is changed to form an electrostatic latent image on the photosensitive drum 56. The exposure device 3 is arranged to face the photosensitive drum 56 in the longitudinal direction (Y-axis direction). The photosensitive drum 56 is installed in the image forming apparatus 1 in parallel with the exposure device 3. The developer develops the electrostatic latent image adhering to the photosensitive drum 56, and forms a toner image on the surface of the photosensitive drum 56. The drum cleaner removes residual toner on the surface of the photosensitive drum 56.

The intermediate transfer belt 53 is an endless belt member that circulates, and the intermediate transfer belt 53 is stretched over a driving roller 69 and a plurality of driven rollers 70, and the intermediate transfer belt 53 rotates in the direction of arrow N.

The intermediate transfer belt 53 is in contact with the photosensitive drum 56 from above (+ Y direction). A primary transfer roller is disposed above the photosensitive drum 56 (+ Y direction) at a position facing the photosensitive drum 56 via the intermediate transfer belt 53. The primary transfer roller is disposed inside the intermediate transfer belt 53. The primary transfer roller transfers the toner image formed on the photosensitive drum 56 onto the intermediate transfer belt 53 when a primary transfer voltage is applied. After the toner images on the photosensitive drums 56 of the plurality of image forming units 51 are sequentially transferred onto the intermediate transfer belt 53 in such a manner as to overlap each other, toner images formed of the toners of the respective colors are formed.

The secondary transfer roller 71 faces the drive roller 69 across the intermediate transfer belt 53. The contact portion between the intermediate transfer belt 53 and the secondary transfer roller 71 constitutes a secondary transfer position. The driving roller 69 drives the intermediate transfer belt 53 to rotate. When the recording medium P passes through the secondary transfer position, a secondary transfer voltage is applied to the secondary transfer roller 71, and the secondary transfer roller 71 secondarily transfers the toner image on the intermediate transfer belt 53 onto the recording medium P.

A belt cleaner 72 is disposed at a position facing one of the driven rollers 70 across the intermediate transfer belt 53. The belt cleaner 72 removes the residual transfer toner on the intermediate transfer belt 53 from the intermediate transfer belt 53. Specifically, the belt cleaner 72 may be a resin member made of urethane or the like.

A conveying path from the paper feed cassette 18 to the secondary transfer roller 71 is provided with a pair of conveying rollers 75 and a pair of registration rollers 76. The pair of transport rollers 75 transport the recording medium P taken out of the paper feed cassette 18 by the paper feed mechanism 19.

The pair of registration rollers 76 align the positions of the leading ends of the recording medium P fed from the pair of transport rollers 75 at the positions where they abut against each other. The positions of the pair of registration rollers 76 in contact with each other constitute registration positions. The pair of registration rollers 76 conveys the recording medium P such that the leading end of the region on the recording medium P to which the toner image is to be transferred reaches the secondary transfer position when the leading end of the toner image reaches the secondary transfer position.

A fixing portion 80 is disposed downstream (upper side in fig. 1) of the secondary transfer roller 71 in the conveying direction of the recording medium P. The fixing unit 80 heats and pressurizes the recording medium P to fix the toner image to the recording medium P.

The discharge roller pair 21 is disposed downstream (upper left side in fig. 1) of the fixing section 80 in the conveying direction of the recording medium P. The discharge roller pair 21 discharges the recording medium P to the sheet discharge portion 22.

A reverse conveyance path 84 is disposed downstream (right side in fig. 1) of the fixing section 80 in the conveyance direction of the recording medium P. The reverse conveyance path 84 reverses the recording medium P and guides the recording medium P to the secondary transfer roller 71. The reverse conveyance path 84 is used when performing duplex printing.

The structure of the exposure apparatus 3 according to the present invention will be described below with reference to fig. 2 to 6.

Fig. 2 is a schematic structural view of the exposure apparatus 3 of the present invention.

Fig. 3 is a schematic plan view of an end portion of the exposure apparatus 3 according to the present invention.

Fig. 4 is a schematic perspective view of an end portion of the exposure apparatus 3 according to the present invention.

Fig. 5 is a schematic perspective view of the exposure apparatus 3 according to the present invention in which the print head 31 is in the contact position, and fig. 5 omits the lift lever 36 for clarity of description.

Fig. 6 is a schematic perspective view of the exposure apparatus 3 according to the present invention in which the print head 31 is at the separated position, and in fig. 6, the lift lever 36 is omitted for clarity of description.

As shown in fig. 2 to 6, in the present embodiment, the exposure apparatus 3 includes a print head 31, a holder 32, a first slide portion 33, an elevating portion 34, a biasing member 35, an elevating lever 36, a second slide portion 37, and a guide portion 38.

The print head 31 has a plurality of light emitting element rows, not shown. Each light emitting element row has a plurality of light emitting elements. The light emitting element is formed of, for example, a light emitting diode. The print head 31 also has a rod lens array that collects light emitted from the light emitting element columns on a photosensitive drum 56 (shown in fig. 1). The rod lens array is disposed between the light emitting element row and the photosensitive drum 56.

The print head 31 exposes the photosensitive drum 56 to form an electrostatic latent image on the photosensitive drum 56. The print head 31 extends in the depth direction (Z-axis direction) of the exposure device 3. The print head 31 is disposed to face the photosensitive drum 56 (shown in fig. 1) in the longitudinal direction (Y-axis direction).

The holder 32 holds the print head 31, and each exposure device 3 has the holder 32 holding the print head 31. The holder 32 has a slit extending in the depth direction (Z-axis direction). The print head 31 is accommodated and fixed in the slit. The print head 31 is located on the upper side (+ Y direction) of the longitudinal direction (Y axis direction) of the carriage 32.

The exposure device 3 has a function of raising and lowering the print head 31, or the exposure device 3 has a function of switching the print head 31 between the abutment position and the separation position. Here, raising the print head 31 means moving the print head 31 in the longitudinal direction (Y-axis direction) toward the upper side (+ Y direction), and the print head 31 comes close to the photosensitive drum 56 while the print head 31 is in the abutment position. And lowering the print head 31 means moving the print head 31 toward the lower side (-Y direction) in the longitudinal direction (Y axis direction), the print head 31 being separated from the photosensitive drum 56 with the print head 31 being at the separation position. The print head 31 moves upward (+ Y direction) in the longitudinal direction (Y axis direction) when moving from the separation position to the abutment position, and moves downward (-Y direction) in the longitudinal direction (Y axis direction) when moving from the abutment position to the separation position.

In the present embodiment, the exposure apparatus 3 moves the carriage 32 in the longitudinal direction (Y-axis direction) in conjunction with the movement of the first slide portion 33 in the depth direction (Z-axis direction) by the elevating portion 34, and the elevating portion 34 converts the movement of the first slide portion 33 in the depth direction (Z-axis direction) into the movement of the carriage 32 in the longitudinal direction (Y-axis direction) to raise and lower the print head 31.

The first slide portion 33 is a groove-shaped slider extending in the depth direction (Z-axis direction), the first slide portion 33 is movable in the extending direction (Z-axis direction, depth direction) of the print head 31, and the first slide portion 33 is located on the lower side (-Y direction) of the carriage 32 in the longitudinal direction (Y-axis direction).

The raising and lowering unit 34 supports the carriage 32 to which the print head 31 is attached, and switches the print head 31 between an abutment position where the print head 31 abuts against the photosensitive drum 56 and a separation position where the print head is separated from the photosensitive drum 56 by raising and lowering the carriage 32 to which the print head 31 is attached, where raising and lowering refers to moving the carriage 32 in the longitudinal direction (Y-axis direction).

As an example, a mode in which the first slide portion 33 is moved in the depth direction (Z-axis direction) of the exposure apparatus 3 by the lifting portion 34 in conjunction with the lifting and lowering of the carriage 32 will be described below, and a configuration of the lifting portion 34 will be described below, but this is not limitative, and another configuration may be adopted in which the movement of the first slide portion 33 is linked with the lifting and lowering of the carriage 32. In addition, although an example in which the exposure apparatus 3 has the elevating portions 34 at both ends in the depth direction (Z-axis direction) is described below as an example, this is not limitative, and a plurality of elevating portions 34 may be provided in the depth direction (Z-axis direction) of the exposure apparatus 3.

In the present embodiment, the elevating sections 34 are provided at positions near both ends of the exposure apparatus 3 in the depth direction (Z-axis direction), and each elevating section 34 includes an elevating link 341 and a fixed-side link 342. Each of the lifting link 341 and the fixed-side link 342 has the same mechanism, and the carriage 32 is supported by the lifting link 341 and the fixed-side link 342 to move between an abutment position for bringing the print head 31 close to the photosensitive drum 56 and a separation position for bringing the print head 31 away from the photosensitive drum 56.

The lifting link 341 is formed in an elongated rod shape having a certain length, the lifting link 341 has a length in the extending direction, one end of the lifting link 341 in the extending direction is connected to the first sliding portion 33, and the lifting link 341 is freely rotatable (rotatable about the X axis) about a connection point connected to the first sliding portion 33, the other end of the lifting link 341 in the extending direction is connected to the bracket 32, and the lifting link 341 is freely rotatable (rotatable about the X axis) about a connection point connected to the bracket 32.

The fixed-side link 342 is formed in an elongated rod shape having a certain length, and the fixed-side link 342 is formed slightly shorter than the lifting link 341. The fixed-side link 342 supports the lifting link 341. One end of the fixed side link 342 in the extending direction is connected to a not-shown housing that supports the elevating portion 34, and the fixed side link 342 is rotatable (rotatable about the X axis) about a connection point connected to the housing of the elevating portion 34, and the other end of the fixed side link 342 in the extending direction is connected to the center of the elevating link 341 in the extending direction, and the fixed side link 342 is rotatable (rotatable about the X axis) about a connection point connected to the elevating link 341.

In the present embodiment, the holder 32 is restricted to be movable only in the longitudinal direction (Y-axis direction), the first sliding portion 33 is restricted to be movable only in the depth direction (Z-axis direction), and both ends of the raising/lowering link 341 and both ends of the fixed-side link 342 are supported to be rotatable about the X-axis.

In the present embodiment, the print head 31 is located at the contact position by default, that is, in the state shown in fig. 2, and at this time, the fixed-side link 342 of the elevating unit 34 supports the center of the elevating link 341 so as to be inclined obliquely upward, that is, inclined toward the front (Z direction). The center of the lifting link 341 is supported by the fixed-side link 342, and the lifting link 341 is inclined in a direction opposite to the direction in which the fixed-side link 342 is inclined, that is, in the rear direction (+ Z direction). Since the carriage 32 is limited to be movable only in the longitudinal direction (Y-axis direction), the lifting link 341 lifts up the carriage 32 mounted with the print head 31,

when the print head 31 is switched from the abutment position to the separation position, the carriage 32 moves downward (-Y direction) in the longitudinal direction (Y-axis direction). Since the housing of the elevating portion 34 is held at a fixed position, the position of the end of the fixed-side link 342 connected to the housing of the elevating portion 34 does not change in the longitudinal direction (Y-axis direction) and the depth direction (Z-axis direction). At this time, when the end of the elevating link 341 connected to the holder 32 in the elevating part 34 moves downward (-Y direction) along with the holder 32 by rotating around the X axis, since the position of the end of the fixed side link 342 connected to the housing of the elevating part 34 does not change, the end of the fixed side link 342 connected to the center of the elevating link 341 also moves downward (-Y direction) by rotating around the X axis. At this time, the lifting link 341 and the fixed-side link 342 are gradually changed from a state of being inclined obliquely upward to a state of being parallel to the depth direction (Z-axis direction), and one end of the lifting link 341 connected to the first sliding portion 33 is pressed toward the front side (Z-direction) in the depth direction (Z-axis direction) by rotating about the X-axis. At this time, as the print head 31 moves toward the lower side (-Y direction) in the longitudinal direction (Y axis direction), the first slide portion 33 moves toward the front side (-Z direction) in the depth direction (Z axis direction). The lifting part 34 converts the movement of the holder 32 in the longitudinal direction (Y-axis direction) into the movement of the first sliding part 33 in the depth direction (Z-axis direction) with respect to the movement of the holder 32 in the longitudinal direction (Y-axis direction). That is, the first slide portion 33 moves in the depth direction (Z-axis direction) of the exposure apparatus 3 in conjunction with the up-and-down movement of the carriage 32.

When the print head 31 is switched from the separation position to the contact position, the first slide portion 33 moves to the rear side (+ Z direction) in the depth direction (Z axis direction), one end of the lifting link 341 in the lifting portion 34 connected to the first slide portion 33 moves along with the first slide portion 33 by rotating about the X axis, one end of the fixed link 342 connected to the housing of the lifting portion 34 does not move along with the movement of the first slide portion 33, and the other end of the fixed link 342 supports the center of the lifting link 341, so that the lifting link 341 and the fixed link 342 gradually change from a state parallel to the depth direction (Z axis direction) to a state inclined obliquely upward, the fixed link 342 starts to support the lifting link 341 along with the movement of the first slide portion 33, and the lifting link 341 pushes up the carriage 32. The raising and lowering section 34 converts the movement of the first slide section 33 in the depth direction (Z-axis direction) into the movement of the carriage 32 in the longitudinal direction (Y-axis direction) with respect to the movement of the first slide section 33 in the depth direction (Z-axis direction). That is, the first slide portion 33 moves in the depth direction (Z-axis direction) of the exposure apparatus 3 in conjunction with the up-and-down movement of the carriage 32.

That is, when the print head 31 is at the abutment position, the first slide portion 33 is moved to the front side in the depth direction (Z-axis direction) (-Z direction) by the lifting portion 34, and the carriage 32 is lowered in accordance with the movement of the first slide portion 33. In contrast, when the first slide portion 33 is moved to the rear side (+ Z direction) in the depth direction (Z axis direction) from the state where the ascending/descending portion 34 is lowered, the ascending/descending portion 34 ascends along with the movement of the first slide portion 33.

By the above connection relationship, the lifting portion 34 connects the first slide portion 33 and the holder 32 to each other, and constitutes a relationship in which the movement of the first slide portion 33 in the depth direction (Z-axis direction) and the movement of the holder 32 in the longitudinal direction (Y-axis direction) are interlocked.

The biasing member 35 of the exposure apparatus 3 is provided at one end of the first slide portion 33 in the depth direction (Z-axis direction), for example, at the rear side (+ Z direction) end in the present embodiment. The biasing member 35 is connected to the rear end (+ Z direction) of the first slide portion 33, and the biasing member 35 is, for example, a coil spring. The biasing member 35 biases the first slide portion 33 in the depth direction (Z-axis direction).

The biasing member 35 biases the first slide portion 33 toward the rear side (+ Z direction) in the depth direction (Z axis direction), so that the print head 31 is not lowered by unexpected movement of the first slide portion 33 toward the front side (-Z direction) in the depth direction (Z axis direction) when the print head 31 is at the abutment position.

Here, although the biasing member 35 is formed of a coil spring, the present invention is not limited to this, and may be formed of an elastic body such as a plate spring, rubber, or sponge. Further, although the example in which the urging member 35 is formed of one coil spring is shown, the present invention is not limited thereto, and the urging member 35 may be formed of a plurality of coil springs or the like.

As shown in fig. 2 to 6, the exposure apparatus 3 further includes a second slide portion 37, and the second slide portion 37 of the exposure apparatus 3 is provided at one end in the depth direction (Z-axis direction) of the first slide portion 33, for example: the front side (end in the (-Z direction)). The second slide portion 37 is a columnar slide member extending in the depth direction (Z-axis direction), and the second slide portion 37 is movable in the extension direction (Z-axis direction, depth direction) of the print head 31. The second sliding portion 37 is connected to the first sliding portion 33, and the second sliding portion 37 moves in the depth direction (Z-axis direction) in accordance with the movement of the first sliding portion 33 in the depth direction (Z-axis direction), and the second sliding portion 37 is supported so as to be rotatable about its own axis.

In the present embodiment, as an example, the first sliding portion 33 and the second sliding portion 37 are connected by a step screw 39, and the step screw 39 is provided coaxially with the second sliding portion 33 and the second sliding portion 37. Thereby, the second slide portion 37 can move in accordance with the movement of the first slide portion 33 in the depth direction (Z-axis direction), and the function of the second slide portion 37 to freely rotate about its own axis, that is, to freely rotate about the axis of the step screw 39 is realized.

Here, although an example in which the first sliding portion 33 and the second sliding portion 37 are connected by the stepped screw 39 is shown, the present invention is not limited to this, and any method may be used as long as it is sufficient that the first sliding portion 33 and the second sliding portion 37 are connected, the second sliding portion 37 moves in accordance with the movement of the first sliding portion 33, and the second sliding portion 37 can rotate around its own axis.

Although the above description shows an example in which the second slide portion 37 is located on the front side (-Z direction) of the first slide portion 33 and the biasing member 35 is located on the rear side (+ Z direction) of the first slide portion 33, the present invention is not limited to this, and any other examples may be used as long as the second slide portion 37 and the biasing member 35 are located on both ends in the depth direction (Z axis direction) of the first slide portion 33.

A projection 371 is formed on the outer peripheral surface of the second sliding portion 37, and the projection 371 is a boss extending outward in the radial direction of the second sliding portion 37.

A guide portion 38 is fitted around the outer peripheral surface of the second sliding portion 37, the guide portion 38 has a cylindrical shape coaxial with the second sliding portion 37, and the guide portion 38 is fitted around the outer peripheral surface of the second sliding portion 37 through the cylindrical shape and covers most of the second sliding portion 37. The guide portion 38 is fixed to, for example, the main body 11 of the image forming apparatus 1, and therefore, the guide portion 38 does not move in accordance with the movement of the second sliding portion 37. The guide portion 38 has a guide groove 381 on the cylindrical surface thereof for exposing the protrusion 371 of the second sliding portion 37, and the guide groove 381 guides the protrusion 371 of the second sliding portion 37 to move in the extending direction of the guide groove 381.

In the present embodiment, the guide groove 381 is formed to extend spirally on the outer peripheral surface of the guide portion 38 so as to extend in the depth direction (Z-axis direction) toward the front side (-Z direction) on the outer peripheral surface of the guide portion 38 and extend in the circumferential direction of the guide portion 38. Both ends of the guide groove 381 in the extending direction form limit positions that restrict the further movement of the protrusion 371, and the guide groove 381 is formed to have a shape that allows the protrusion 371 to move continuously between the two limit positions.

When the print head 31 is switched from the abutment position shown in fig. 5 to the separation position shown in fig. 6, that is, when the first slider 33 moves toward the front side (-Z direction) in the depth direction (Z axis direction), the second slider 37 moves toward the front side (-Z direction) along with the first slider 33, and at this time, the protrusion 371 of the second slider 37 is guided by the guide groove 381 of the guide portion 38, and the guide portion 38 restricts excessive movement of the second slider 37 and the first slider 33 in the depth direction (Z axis direction) to some extent according to the spirally extending shape of the guide groove 381. The second sliding portion 37 is configured such that the protrusion 371 rotates the second sliding portion 37 about its axis in accordance with the extending direction of the guide groove 381, so as to be movable in the depth direction (Z-axis direction) in accordance with the first sliding portion 33.

Conversely, the rotation of the second slide portion 37 about its own axis is converted into the movement of the second slide portion 37 and the first slide portion 33 in the depth direction (Z-axis direction) by the guide groove 381 of the guide portion 38 and the protrusion 371 of the second slide portion 37, and the abutment position and the separation position of the print head 31 can be switched by the rotation of the second slide portion 37 about its own axis. When the lift unit 34 lifts up and down the print head 31 in the longitudinal direction (Y-axis direction), the projection 371 formed on the second slide unit 37 continuously moves between the extreme positions of the two ends in the extending direction of the guide groove 381 of the guide unit 38, and when the projection 371 is located at the two extreme positions of the ends of the guide groove 381, the lift unit 34 supports the print head 31 at the abutment position and the separation position, respectively.

The guide portion 38 guides the movement of the print head 31 in the longitudinal direction (Y-axis direction) by guiding the movement of the second slide portion 37 and the first slide portion 33 in the depth direction (Z-axis direction) that moves together with the second slide portion 37 in the depth direction (Z-axis direction).

In order to operate the second sliding portion 37 to rotate around its own axis, a lift lever 36 is provided at an end portion on the front side (in the (-Z direction) in the depth direction (in the Z axis direction) of the second sliding portion 37. The second sliding portion 37 is attached coaxially with the lift lever 36, the second sliding portion 37 is provided so as to be rotatable in accordance with the rotation of the lift lever 36, and the second sliding portion 37 is supported by the lift lever 36 so as to be movable in the depth direction (Z-axis direction) inside the lift lever 36. By linking the rotation of the lift lever 36 and the rotation of the second slide portion 37, the second slide portion 37 can be operated to rotate around its axis more easily, and the contact position and the separation position of the print head 31 can be switched by the lift lever 36.

When the print head 31 is lowered from the abutment position to the separation position by the raising and lowering portion 34, since the urging member 35 always keeps pulling the first slide portion 33 and the second slide portion 37 toward the rear side (+ Z direction) in the depth direction (Z axis direction), the load thereof is applied to the guide groove 381 of the guide portion 38 through the protrusion 371 of the second slide portion 37.

Hereinafter, a case where the guide groove 381a of the guide portion 38a is deformed when the print head 31a is moved up and down in the exposure apparatus 3a according to the related art and the print head 31a is deviated from the predetermined contact position and the predetermined separation position will be described with reference to fig. 7.

Fig. 7 is a partial schematic top view of the print head 31a of the exposure apparatus 3a in the prior art in a separated position.

In fig. 7, for the sake of better clarity, only one end of the exposure device 3a where the guide portion 38a is provided is shown, and one end of the exposure device 3a where the biasing member is provided is omitted.

In the related art, when the print head 31a is at the separation position as shown in fig. 7, the protrusion 371a of the second slider 37a moves to one end in the extending direction of the guide groove 381a of the guide portion 38a, which is the extreme position of the guide groove 381a for guiding the protrusion 371 a. At this time, the biasing member of the exposure apparatus 3a always biases the first slide portion 33a toward the rear side (+ Z direction) in the depth direction (Z-axis direction), and the force is applied to the guide groove 381a of the guide portion 38a through the first slide portion 33a, the second slide portion 37a, and the protrusion 371 a. In the prior art, the guide groove 381a has an open shape, and when the protrusion 371a is located at the above-described limit position of the guide groove 381a, the side surface of the guide groove 381a is pressed by the protrusion 371a by the pressure of the urging member, and the guide groove 381a may be deformed toward the urging member side in the depth direction (Z-axis direction).

When the guide groove 381a is deformed toward the biasing member, the limit position where the movement of the projection 371a is restricted by the guide groove 381a is displaced, and the print head 31 cannot be lowered to a predetermined position or deviated from a predetermined separation position, and the image forming unit 51 cannot be pulled out of the main body 11.

Hereinafter, a configuration of preventing the guide portion 38 from being deformed and holding the print head at a predetermined position in the exposure apparatus 3 according to the present invention will be described with reference to fig. 3 to 6 and fig. 8 and 9.

Fig. 8 is a perspective view of the guide portion 38 in the exposure device 3 according to the present invention.

Fig. 9 is a schematic perspective view of the exposure apparatus 3 according to the present invention in which the print head 31 is at the separated position, and in fig. 9, the lift lever 36 is omitted for clarity of description.

As shown in fig. 3, 4, 5, and 6, in the present embodiment, the guide portion 38 is fitted around the outer peripheral surface of the second sliding portion 37 via a cylinder, the cylindrical surface of the guide portion 38 has a guide groove 381 that exposes the protrusion 371 of the second sliding portion 37, and the guide groove 381 guides the protrusion 371 of the second sliding portion 37 to move in the direction in which the guide groove 381 extends spirally.

As shown in fig. 8, one end of the guide groove 381 in the spiral extending direction near the first sliding portion 33 forms a groove surface 382 that restricts further movement of the protrusion 371, the groove surface 382 having a function of restricting further movement of the protrusion 371 in the guide groove 381. When the projection 371 moves to the groove surface 382, the limit position is reached. As shown in fig. 5, when the protrusion 371 is guided to one end in the spiral extending direction by the guide groove 381 in accordance with the rotation of the second sliding portion 37 about its axis, that is, when the protrusion 371 moves to the limit position, the protrusion 371 abuts on the groove surface 382, and the movement of the protrusion 371 is restricted. At this time, the print head 31 is positioned at the abutment position by the interlocking of the second slide portion 37, the first slide portion 33, and the lifting portion 34.

As shown in fig. 8, an end surface for restricting the movement of the projection 371 is not formed at the other end of the guide groove 381 away from the first sliding portion 33 in the spiral extending direction, and the other end of the guide groove 381 penetrates the abutment wall 383 of the guide portion 38 to form an open end. As shown in fig. 6, when the protrusion 371 is guided to the other end in the spiral extending direction by the guide groove 381 in accordance with the rotation of the second sliding portion 37 about its axis, the protrusion 371 comes out of the guide groove 381, and the protrusion 371 abuts against an abutment wall 383 of the guide portion 38 orthogonal to the depth direction (Z-axis direction) of the exposure apparatus 3. The surface of the contact wall 383 that contacts the protrusion 371 is a surface of the guide portion 38 that faces away from the first sliding portion 33 in the depth direction (Z-axis direction). The print head 31 is held at the separated position by locking the protrusion 371 of the second slider 37 to the surface of the abutment wall 383 distant from the first slider 33 in the depth direction (Z-axis direction).

In the present embodiment, when the print head 31 is at the separation position, the biasing member 35 biases the first slide portion 33 in the depth direction (Z-axis direction), and the side surface of the guide groove 381 does not contact the protrusion 371. At this time, the protrusion 371 abuts against the abutment wall 383, and the surface area of the surface of the abutment wall 383 which contacts with the protrusion 371 is much larger than the surface area of the surface of the guide groove 381a which contacts with the protrusion 371a in the related art, so that the abutment wall 383 is not easily deformed. It is possible to prevent the print head 31 from failing to descend to a predetermined position due to the deformation of the guide portion 38.

As shown in fig. 9, the guide portion 38 is generally fixed to the main body 11 of the image forming apparatus 1 by a fixing screw 384, and a surface of the contact wall 383 that contacts the projection 371 is a surface that faces away from the first sliding portion 33 in the depth direction (Z-axis direction), and at this time, a position where the contact wall 383 contacts the projection 371 is located near the fixing screw 384 of the fixing guide portion 38. Even when the load of the urging member 35 is applied from the projection 371 of the second slider 37 to the abutment wall 383 of the guide portion 38, since the portion where the projection 371 abuts against the abutment wall 383 of the guide portion 38 is close to the fixing point (the fixing screw 384) of the guide portion 38 and the main body 11, the face of the abutment wall 383 of the guide portion 38 which contacts with the projection 371 has substantially the same high rigidity as the main body 11, and therefore the portion where the abutment wall 383 contacts with the projection 371 is not easily deformed, whereby it is possible to prevent the print head 31 from failing to descend to the predetermined position due to the deformation of the guide portion 38.

According to at least one embodiment described above, when the projection of the second sliding portion of the exposure apparatus is guided to one end by the guide groove, the projection is brought into contact with the contact wall of the guide portion orthogonal to the depth direction of the exposure apparatus, and even when the urging member applies a load to the first sliding portion during the print head up-and-down operation, the guide portion that guides the print head up-and-down operation does not deform, and the print head does not deviate from the predetermined contact position and separation position.

While several embodiments of the present invention have been described, these embodiments have been presented by way of example only, and are not intended to limit the scope of the invention. These new embodiments can be implemented in other various manners, and various omissions, substitutions, combinations, and changes can be made without departing from the gist of the present invention. These embodiments and modifications are included in the scope and gist of the present invention, and are included in the present invention described in the claims and the equivalent scope thereof.

Claims (10)

1. An exposure apparatus, comprising:

a print head that exposes the photosensitive drum and forms an electrostatic latent image on the photosensitive drum;

a lifting part which supports and lifts a support on which the print head is mounted;

a first sliding unit that moves in the depth direction of the exposure device in conjunction with the lifting and lowering of the carriage;

a biasing member that is provided at one end of the first slide portion and biases the first slide portion in the depth direction;

a second sliding portion connected to the first sliding portion and moving along with the movement of the first sliding portion, the second sliding portion having a protrusion formed on an outer circumferential surface thereof; and

a guide part which is sleeved on the periphery of the second sliding part and is provided with a guide groove for guiding the protrusion,

wherein the projection abuts against a groove surface of the guide groove when guided to one end by the guide groove, and the projection abuts against an abutment wall of the guide portion orthogonal to the depth direction when guided to the other end by the guide groove.

2. The exposure apparatus according to claim 1,

a surface of the abutting wall that contacts the protrusion is a surface of the guide portion that faces away from the first sliding portion in the depth direction.

3. The exposure apparatus according to claim 1,

the second sliding part is connected with the first sliding part through a step screw.

4. The exposure apparatus according to claim 1,

the lifting part is provided with a lifting connecting rod, one end of the lifting connecting rod is connected with the support, and the other end of the lifting connecting rod is connected with the first sliding part.

5. The exposure apparatus according to claim 4,

the lifting part is also provided with a fixed side connecting rod, one end of the fixed side connecting rod is connected with the center of the lifting connecting rod, and the other end of the fixed side connecting rod is connected with the shell of the lifting part.

6. An image forming apparatus, comprising:

an original conveying portion that conveys an original to be transferred;

a scanner section that reads the original to generate image data of the original;

an image forming unit that forms a toner image according to the image data;

a fixing section that fixes the toner image on a recording medium; and

an exposure device that irradiates exposure light to the image forming unit,

the exposure device comprises:

a print head that exposes the photosensitive drum and forms an electrostatic latent image on the photosensitive drum;

a lifting part which supports and lifts a support on which the print head is mounted;

a first sliding unit that moves in the depth direction of the exposure device in conjunction with the lifting and lowering of the carriage;

a biasing member that is provided at one end of the first slide portion and biases the first slide portion in the depth direction;

a second sliding portion connected to the first sliding portion and moving along with the movement of the first sliding portion, the second sliding portion having a protrusion formed on an outer circumferential surface thereof; and

a guide part which is sleeved on the periphery of the second sliding part and is provided with a guide groove for guiding the protrusion,

wherein the projection abuts against a groove surface of the guide groove when guided to one end by the guide groove, and the projection abuts against an abutment wall of the guide portion orthogonal to the depth direction when guided to the other end by the guide groove.

7. The image forming apparatus according to claim 6,

a surface of the abutting wall that contacts the protrusion is a surface of the guide portion that faces away from the first sliding portion in the depth direction.

8. The image forming apparatus according to claim 6,

the second sliding part is connected with the first sliding part through a step screw.

9. The image forming apparatus according to claim 6,

the lifting part is provided with a lifting connecting rod, one end of the lifting connecting rod is connected with the support, and the other end of the lifting connecting rod is connected with the first sliding part.

10. The image forming apparatus according to claim 9,

the lifting part is also provided with a fixed side connecting rod, one end of the fixed side connecting rod is connected with the center of the lifting connecting rod, and the other end of the fixed side connecting rod is connected with the shell of the lifting part.

Images