JP4631352B2 - Image forming apparatus - Google Patents

Description

  The present invention relates to an image forming apparatus such as a digital copying machine or a laser beam printer having a structure in which an optical scanning device is attached to a chassis or a frame.

  In general, in an image forming apparatus such as a full-color or black-and-white copying machine or printer using an electrophotographic system, for example, a photosensitive member formed in a drum shape in a developing device is uniformly charged, and this photosensitive member is used as an optical scanning device. An electrostatic latent image is formed on the photosensitive member by exposure with light controlled by the (scanning optical device) based on the image information. The electrostatic latent image is converted into a visible image (toner image) with toner, and the toner image is further transferred onto a recording paper (recording medium), which is fixed by a fixing device to form an image.

  Some conventional color image forming apparatuses have a structure in which a plurality of developing devices are arranged substantially vertically and the optical scanning device is attached to a substantially vertical frame. In the color image forming apparatus having such a structure, when the optical scanning device is attached to the vertical surface of the frame (chassis), the optical scanning device is prevented in order to prevent the optical scanning device from falling and to simplify the assembly process. The U-shaped member provided in the device is temporarily locked by hooking it into the loose insertion hole drilled in the vertical frame, and then the operator lifts the optical scanning device and inserts the positioning pin into the positioning hole for positioning. It has been proposed to perform the work of fixing the optical scanning device to the vertical frame after the state is held (see, for example, Patent Document 1).

However, in such a conventional means for fixing the optical scanning device to the vertical frame, after temporarily fixing the optical scanning device to the vertical frame, the operator scans the optical scanning device again to position the optical scanning device. While holding the positioning pin with one hand and holding the positioning pin in the positioning hole, the fixing work such as a screw and a tool must be used for fixing, and there is a problem that workability is poor.
JP 2003-295086 A

  SUMMARY OF THE INVENTION In view of the above-described problems, an object of the present invention is to newly provide an image forming apparatus configured to improve workability of a work process for attaching an optical scanning device to a chassis or a frame during assembly manufacture or maintenance. .

The image forming apparatus according to claim 1 is an image forming apparatus having a structure in which the optical scanning device is positioned and fixed to the substantially vertical attachment portion of the frame member by the positioning support means, and the frame member is substantially vertical When the optical scanning device is supported by the positioning support means with respect to the mounting portion, the optical scanning device stops the operation of rotating about the positioning support means by its own weight and holds the temporarily fixed state. An end side to be attached to the frame in a housing provided in the optical scanning device from an extension line passing through a center point of a small-angle rotation operation in the positioning support device provided with the movable scanning range regulating device. L1 is the distance to the upper end surface of the frame, and when the housing is rotated around the center point of the small angle rotation operation in the positioning support means, When the distance to the end of the housing in contact is L2, and the distance between the side of the housing closest to the frame and the side surface of the frame in a state where the optical scanning device is fixed to the frame is a, The movable range restricting means is configured by forming a dimension shape that satisfies the formula L2> L1 + a.

  With the above-described configuration, when the optical scanning device is installed on the substantially vertical attachment portion of the frame member, the optical scanning device tries to rotate around its positioning support means under its own weight, but the movable range The restricting means stops this operation and holds it in a temporarily fixed state, so that the posture of the optical scanning device can be brought into a state that is almost completely assembled. Therefore, the operator does not need to hold the optical scanning device with one hand or hold it with a jig that supports the optical scanning device, so that the one hand is not blocked and the optical scanning device is fixedly assembled to the frame member. Work can be done easily.

Further, in addition to the above-described operations and effects, when the optical scanning device is positioned by the positioning support means with respect to the substantially vertical mounting portion of the frame member, the optical scanning device is centered on the positioning support means by its own weight. It is possible to realize a structure in which the side of the housing as the movable range restricting means and the side surface of the frame come into contact with each other and the optical scanning device does not drop from the frame before being fixed, so that the optical scanning device is temporarily fixed.

According to a second aspect of the invention, in the image forming apparatus according to claim 1, positioning支受means, characterized in that it is a structure for positioning and inserting the positioning pin into the insertion hole.

The invention of claim 3 is the image forming apparatus according to claim 1, positioning支受means has a structure for positioning by支受shaft-like support shaft member in a V-shaped positioning groove It is characterized by that.

By configuring as described above, in addition to the operation and effect of the invention of the first aspect, the positioning support means can be configured at a low cost with a simple configuration.

  According to the image forming apparatus of the present invention, it is possible to improve the workability of the work process for attaching the optical scanning device to the chassis or the frame at the time of assembly manufacture or maintenance.

  A first embodiment relating to an image forming apparatus of the present invention will be described with reference to FIGS.

  The image forming apparatus in which the optical scanning device is mounted on the vertical frame according to the first embodiment is configured as a tandem type full color printer as shown in FIG. Inside the main body 10 of the full-color printer, a ROS (Raster Output Scanner) that is an optical scanning device 12 and a print head device 14 (Print Head Device) that is an image forming unit that performs full-color image formation are installed. .

  The print head device 14 includes four photosensitive drums 16, 18, 20, and 22 as image carriers. The optical scanning device 12 performs image exposure processing on the four photosensitive drums 16, 18, 20, and 22. Each of the four photosensitive drums 16, 18, 20, and 22, which are image carriers incorporated in the print head device 14, is provided with a developing device 23 for each color.

  In the main body 10 of this full-color printer, the print head device 14 receives a supply of a recording medium (recording paper) from a paper feed cassette 25 to transfer a toner image, and the fixing device 27 fixes the toner image to the recording medium transferred. The recording medium that has been processed and on which the image is formed is configured to be discharged onto a discharge tray.

  Although not shown, the optical scanning device 12 includes four laser beams including image information of each color of yellow (Y), magenta (M), cyan (C), and black (K). A laser light source including a semiconductor laser array that emits light is provided. The laser beam emitted from the laser light source passes through the collimator lens and the cylindrical lens, is adjusted to a parallel beam, and enters the rotary reflecting mirror (for example, a polygon mirror device) 26.

  The laser beam reflected by the rotary reflecting mirror 26 passes through the scanning lens 28 and enters the separating polygon mirror 30 which is a separating means. The reflecting surface of the separating polygonal mirror 30 is formed by a plane (two orthogonal planes) including two adjacent sides of a substantially square shape. The position of the laser light source is adjusted so that four laser beams are incident on the separating polygon mirror 30 at an optical path in which two laser beams are symmetric at approximately equal intervals.

  In each direction reflected by the reflecting surface of the separating polygonal mirror 30, four reflecting mirrors 32 that respectively reflect four lasers are arranged at substantially symmetrical positions with respect to the separating polygonal mirror 30. The respective laser beams reflected by these reflecting mirrors 32 are incident on and reflected by four cylindrical mirrors 34 arranged at substantially symmetrical positions with respect to the separating polygonal mirror 30.

  The laser beams reflected by the four cylindrical mirrors 34 pass through four substantially parallel optical paths, respectively, and four photosensitive drums 16, 18, 20, 22 (an image carrier other than the photosensitive drum may be used) and an electrostatic latent image is formed on the surface thereof.

  As shown in FIGS. 1 to 3, in the full-color printer main body 10, the optical scanning device 12 is attached to a frame 36 disposed therein. In this frame 36, a portion to which the optical scanning device 12 is attached is formed in a frame shape arranged vertically (substantially vertical). Note that the portion of the frame 36 to which the optical scanning device 12 is attached may be set obliquely within a range of a predetermined allowable angle from the vertical, for example.

  An attachment portion of the optical scanning device 12 of the frame 36 is formed in a rectangular frame shape that is slightly larger than the outer shape of the housing 24 so that the housing 24 of the optical scanning device 12 can be inserted. An opening 38 is provided in a portion of the frame 36 where the optical scanning device 12 is attached so that the laser beam emitted from the optical scanning device 12 can reach the four photosensitive drums 16, 18, 20, and 22.

  In addition, positioning pins 40 serving as positioning support means protrude from the rectangular frame-like portion of the frame 36 to which the optical scanning device 12 is attached, at two predetermined locations near the lower sides of both sides of the rectangular frame. Mounting screw holes 42 are drilled in the frame-like portion of the frame 36 adjacent to the positioning pins 40, respectively. The positioning pins 40 and the mounting screw holes 42 are provided in each reinforcing member 44 fixed to the side surface of the frame 36.

  Further, a reinforcing member 48 having a mounting screw hole 46 drilled is fixed to a predetermined position in the center of the upper side of the rectangular frame-shaped portion to be attached to the optical scanning device 12 of the frame 36. That is, mounting screw holes 42 and 46 are arranged at three predetermined positions on the frame 36.

  The housing 24 of the optical scanning device 12 has a predetermined set of left and right lower sides corresponding to a set of positioning pins 40 and mounting screw holes 42 and mounting screw holes 46 respectively arranged at three predetermined positions of the frame 36. Small rectangular protruding piece-like support pieces 50A and 50B protruding from positions and small rectangular protruding piece-like support pieces 52 protruding from a predetermined position at the center of the top are provided.

  One support piece 50A is provided with an insertion hole 54 as a positioning support means for inserting the positioning pin 40 without play and positioning it uniquely, and a screw insertion hole 56. The other support piece 50B is provided with an insertion hole 58 as a positioning support means, which is a long hole for inserting the positioning pin 40 and positioning in the height direction, and a screw insertion hole 56. To do. The insertion hole 58 serving as a positioning support means, which is a long hole, provides a play for assembling with a predetermined width with respect to the horizontal direction (for example, the horizontal direction) of the housing 24 of the optical scanning device 12, so The positioning pin 40 is movably inserted in the direction, and the positioning pin 40 is inserted without play so as not to move in the height direction.

  Furthermore, a screw insertion hole 56 is drilled in the support piece 52 protruding from a predetermined position at the center of the top of the housing 24.

  Further, in the main body 10 of this full-color printer, at the time of assembly manufacture or maintenance such as replacement of the optical scanning device 12, the housing 36 of the optical scanning device 12 can be held in a temporarily fixed state on the frame 36. A portion for attaching the housing 24 of the optical scanning device 12 to the frame 36 is set to a predetermined size so that the operation of attaching the scanning device 12 can be easily performed.

  Therefore, as shown in FIG. 5, the main body 10 of the full-color printer has an insertion hole 54 and a long hole on the housing 24 side of the optical scanning device 12 corresponding to the center point of the small-angle rotation operation of the positioning support means. L1 is a distance from an extension line of a predetermined position of the center line with the insertion hole 58 (here, a predetermined position corresponding to the center line of the positioning pin 40) to the upper end surface on the end side attached to the frame 36 of the housing 24. From the center point when the housing 24 is rotated by a required angle in a state where the corresponding positioning pins 40 are inserted into the insertion hole 54 on the housing 24 side and the insertion hole 58 which is a long hole, When the housing 24 is rotated around the point, the distance to the side (upper end corner) of the housing 24 closest to the frame 36 is L2, and the optical scanning device 12 is fixed to the frame 36. And the side of housing 24 closest to the frame 36 described above in a state, when the distance between the upper inner side surface 38A of the frame is a, constitute the dimensions of formula L2> L1 + a is established.

  In such a configuration, a part of the housing 24 of the optical scanning device 12 is inserted into the opening 38 of the frame 36, and corresponds to the insertion hole 54 on the housing 24 side and the insertion hole 58 that is a long hole, respectively. When the positioning pin 40 is inserted, the center of gravity of the optical scanning device 12 is on the rotary reflecting mirror 26 side, so that a moment to rotate in the direction away from the frame 36 acts on the housing 24 of the optical scanning device 12.

  When the moment acts in this way, the optical scanning device 12 includes two positioning pins 40 inserted into the insertion hole 54 on the housing 24 side and the insertion hole 58 which is a long hole, respectively, as shown in FIG. The upper end of the housing 24 as the movable range restricting means abuts on the upper inner surface 38A as the movable range restricting means in the opening 38 of the frame 36. Therefore, the optical scanning device 12 has a contact between the two positioning pins 40 inserted into the insertion hole 54 on the housing 24 side and the insertion hole 58 which is a long hole, and the upper end portion of the housing 24 and the upper inner surface 38A. In a three-point support state with the contact portion, as shown by a solid line in FIG. 6, it is held slightly tilted from an appropriate fixing position indicated by an imaginary line. At this time, the optical scanning device 12 is positioned in the optical scanning direction and the sub-scanning direction by inserting the two positioning pins 40 into the insertion hole 54 and the insertion hole 58 which is a long hole.

  That is, in the state shown in FIG. 6, the mounting screw on the frame 36 side without the optical scanning device 12 dropping from the frame 36 without holding the optical scanning device 12 by hand or holding it with a jig. The holes 42 and 46 and the screw insertion holes 56 respectively corresponding to the holes 42 and 46 are substantially concentric, and are in a temporarily fixed state in which the posture close to the state in which the optical scanning device 12 is completely assembled to the frame 36 is maintained. .

  In this temporarily fixed state, the optical scanning device 12 has an upper end portion of the housing 24 in addition to the two positioning pins 40 respectively inserted into the insertion hole 54 on the housing 24 side and the insertion hole 58 which is a long hole. For example, the optical scanning device 12 is inserted into the insertion hole 54 on the housing 24 side and the insertion hole 58, which is a long hole, respectively. There is a concern that even if the weight of the optical scanning device 12 is large, the positioning pin breaks and the optical scanning device 12 falls, as compared with a structure in which the two positioning pins 40 are set long to support the optical scanning device 12. Can be wiped off.

  Therefore, in the main body 10 of the full-color printer configured as described above, when an operator performs an operation of attaching the optical scanning device 12 to the frame 36 during assembly manufacture or maintenance, the optical scanning is performed on the frame 36 as described above. After the device 12 is temporarily fixed, the screw 60 is passed through the screw insertion hole 56 at the top of the housing 24 and fastened to the mounting screw hole 46, and the screw is inserted into the screw insertion hole 56 of the support piece 50 </ b> A at both lateral bottoms of the housing 24. The housing 24 of the optical scanning device 12 can be fixed to the frame 36 by being fastened to the mounting screw hole 42 through 60 and fastened to the mounting screw hole 42 through the screw insertion hole 56 of the support piece 50B.

  For this reason, the worker performs the work of fastening the screws 60 by using the tools such as a screwdriver with both hands after releasing the hands from the optical scanning device 12 after the optical scanning device 12 is temporarily fixed to the frame 36. Since it can be easily performed, work efficiency can be improved.

  In the main body 10 of the full-color printer, when the optical scanning device 12 is removed, the optical scanning device 12 is held in a temporarily fixed state on the frame 36 even if each screw 60 is removed. It can be prevented from falling and damaged, and the operator can perform the removal work using both hands, so that the work can be easily performed.

  Further, in the main body 10 of this full-color printer, the operation of inserting the housing 24 into the opening 38 is facilitated by forming the upper inner side surface 38A portion of the frame 36 as a tapered structure having a tapered slope. The inclination angle when the optical scanning device 12 is temporarily fixed to the frame 36 can be reduced so that the operation can be performed more easily.

  Next, a second embodiment of the present invention will be described with reference to FIG. In the second embodiment, the structure for fixing the housing 24 of the optical scanning device 12 to the frame 36 is changed.

  In the second embodiment, a reinforcing member 48 is integrally formed at a predetermined position in the center of the upper side of the rectangular frame-shaped portion attached to the optical scanning device 12 of the frame 36, and the mounting screw hole 46 is formed in this reinforcing member 48 portion. , And a positioning pin 40 as a positioning member is projected adjacently.

  Further, support arm members 62 are provided to protrude from the rectangular frame-like portion of the frame 36 to which the optical scanning device 12 is attached, at two predetermined positions near the lower sides of both sides of the rectangular frame. Each support arm member 62 is provided with a V-shaped positioning groove 64.

  Further, a shaft-like support shaft member 66 formed in a columnar shape is provided on the housing 24 of the optical scanning device 12 so as to correspond to each support arm member 62.

  As in the first embodiment, the main body 10 of the full-color printer according to the second embodiment has the optical scanning device 12 mounted on the frame 36 at the time of assembly manufacture or maintenance such as replacement of the optical scanning device 12. 5 is configured to have a dimension and shape that satisfies the formula L2> L1 + a shown in FIG. 5 for enabling the housing 24 to be held in a temporarily fixed state.

  In the second embodiment configured as described above, a part of the housing 24 of the optical scanning device 12 is inserted into the opening 38 of the frame 36, and each support shaft member 66 is placed on the corresponding positioning groove 64. When the moment to rotate in the direction away from the frame 36 is exerted on the upper portion of the housing 24 of the optical scanning device 12 by mounting, the upper end portion of the housing 24 of the optical scanning device 12 is above the opening 38 of the frame 36. It contacts the inner side surface 38A. Further, since the support shaft members 66 projecting from the housing 24 are supported by the corresponding positioning grooves 64 so that the optical scanning device 12 is supported at three points as a whole, the optical scanning device 12 is manually moved. Even if the optical scanning device 12 does not fall from the frame 36 without holding or holding using a jig, the mounting screw holes 42 and 46 on the frame 36 side and the corresponding screw insertion holes 56 are respectively provided. Thus, a substantially fixed state is maintained, and a temporarily fixed state is maintained in which a posture close to a state in which the optical scanning device 12 is completely assembled to the frame 36 is maintained.

  Further, in the main body 10 of this full-color printer, the optical scanning device 12 is arranged such that the positioning pin 40 is inserted into the insertion hole 54 and the support shaft member 66 is placed in each of the two positioning grooves 64, thereby the optical scanning device 12 and the frame. Positioning with respect to the optical scanning direction and the sub-scanning direction is achieved.

  Since the configuration, operation, and effects of the second embodiment other than those described above are the same as those of the first embodiment described above, the same members are denoted by the same reference numerals, and the description thereof is omitted. . Furthermore, it goes without saying that the present invention can have other various configurations without departing from the gist of the present invention.

1 is a schematic vertical sectional view of an image forming apparatus according to a first embodiment of the present invention. 1 is a schematic side view of the inside of an image forming apparatus according to a first embodiment of the present invention. 1 is an exploded perspective view of a portion of a frame and an optical scanning device in an image forming apparatus according to a first embodiment of the present invention. 1 is an exploded perspective view showing a portion where an optical scanning device is attached to a frame in an image forming apparatus according to a first embodiment of the present invention. FIG. FIG. 3 is a partial cross-sectional side view showing a state when the optical scanning device is properly attached to the frame in the image forming apparatus according to the first embodiment of the present invention. FIG. 3 is a partial cross-sectional side view showing a state where the optical scanning device is held in a temporarily fixed state on a frame in the image forming apparatus according to the first embodiment of the present invention. FIG. 6 is an exploded perspective view of portions of a frame and an optical scanning device in an image forming apparatus according to a second embodiment of the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Full-color printer main body 12 Optical scanning device 14 Print head device 24 Housing 36 Frame 38 Opening 38A Upper inner side surface 40 Positioning pin 42 Mounting screw hole 46 Mounting screw hole 48 Reinforcement member 50A Support piece 50B Support piece 52 Support piece 54 Insertion hole 56 Screw insertion hole 58 Insertion hole 62 which is a long hole Support arm member 64 Positioning groove 66 Support shaft member

Claims (3)

In the image forming apparatus having a structure in which the optical scanning device is positioned by the positioning support means and fixed to the substantially vertical mounting portion of the frame member.
When the optical scanning device is supported by the positioning support means with respect to the substantially vertical mounting portion of the frame member, the optical scanning device tries to rotate around the positioning support means by its own weight. Is provided with a movable range restricting means for stopping and holding in a temporarily fixed state,
A distance from an extension line passing through a center point of a small-angle rotation operation in the positioning support means that supports the optical scanning device to an upper end surface on an end side attached to the frame in a housing provided in the optical scanning device. L1
L2 is a distance to the end of the housing that is closest to the frame when the housing is rotated around the center point of the small-angle rotation operation in the positioning support means;
When the distance between the side of the housing closest to the frame and the side surface of the frame when the optical scanning device is fixed to the frame is a,
An image forming apparatus characterized in that the movable range restricting means is configured by forming a dimension shape that satisfies the formula L2> L1 + a. 2. The image forming apparatus according to claim 1, wherein the positioning support means has a structure for positioning by inserting a positioning pin into the insertion hole . 2. The image forming apparatus according to claim 1, wherein the positioning support means has a structure for supporting and positioning a shaft-like support shaft member in a V-shaped positioning groove .

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