JPH0628276Y2 - Laser printer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention is directed to a first block provided with an exposure optical unit that generates a scanning beam modulated based on print data.
With respect to the second block provided with the image forming unit that receives the scanning beam generated by the exposure optical unit on the photoconductor and visualizes the electrostatic latent image using the developer, and transfers the image onto the transfer paper, The present invention relates to a laser printer mounted by a hinge so that the lid can be moved.

(Background of the Invention) In this type of laser printer, the substrate in the first block on which the optical components forming the exposure optical unit are mounted is a support frame (hereinafter, also referred to as a main body) of the first block of the laser printer. It is fixed to.

(Problems to be solved by the invention) Distortion may occur in the main body during assembly and transportation, but in the case of the configuration of the above conventional device, since the board is fixed to the main body, this distortion spreads to the board, In some cases, the positional relationship between the optical components that require high precision may be displaced. In particular, in the case of a structure in which the hinge 1 is used as a fulcrum to open and close, as shown in FIG. 4, which will be described later, the block B1 is fixed by the hook 5, and therefore the block B1 must be pulled upward by a spring. Distortion is likely to occur, and the positional deviation between the optical components described above occurs. In order to prevent this, it is necessary to make the substrate robust by die casting or the like, but there is a problem that it becomes expensive. When the block B1 is mechanically distorted, the positional relationship between the blocks B1 and B2 also changes in the conventional configuration, and the positional relationship between the exposure optical unit and the image forming unit (photoconductor) also shifts. .

The present invention has been made in view of the above problems, and its object is to prevent the positional relationship between the optical components of the exposure optical unit from deviating even when the block B1 is distorted, and the exposure optical unit and the image forming unit ( (EN) It is possible to realize a laser printer which has a simple mounting structure in which the positional relationship with the photoconductor) does not shift, and which requires an inexpensive substrate.

(Means for Solving Problems) According to the present invention for solving the above problems, the first block provided with an exposure optical unit that generates a scanning beam modulated based on print data is the exposure optical unit. The second block is provided with an hinge to open the second block provided with an image forming unit that receives the scanning beam generated in In a movably mounted laser printer, each optical component of the exposure optical unit is disposed on the same substrate in the first block, and one end of the support frame of the first block is the first frame. A plurality of stepped support pins projecting so as to be able to contact the support frame of the second block and slidable in the axial direction within a certain range, and the step portion of the support pins includes the second block and the second block; From the opposite side, each optical component of the exposure optical unit The disposed substrate is brought into contact with the substrate, and the substrate is urged by a spring in a direction such that the support pin projects toward the second block side.

(Operation) In the laser printer according to the present invention, the substrate on which each optical component of the exposure optical unit is arranged is elastically supported with respect to the main body, and the distortion of the main unit is hardly transmitted to the substrate, and the optical of the exposure optical unit is not transmitted. The positional relationship between the parts does not shift. Further, in this closed state, the substrate in the first block is positioned by abutting against the support frame of the second block via the plurality of support pins, so that the exposure optical unit and the image forming unit ( The positional relationship with the photoconductor does not shift.

Embodiment An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram of an exposure optical section in one embodiment of the present invention, FIG. 2 is a sectional view taken along the line II--II of FIG. 1, FIG. 3 is a general block diagram of the above embodiment, and FIG. It is a figure which shows the other operating state of an example.

This embodiment is composed of three blocks B1, B2, B3, and the blocks B1 and B2 are connected by a hinge 1. As shown in FIG. 4, the block B1 is connected to the block B2.
Can open the lid. In FIG. 4, block B
The link mechanism for holding the open state of No. 1 is also shown. That is, the link mechanism for keeping the block B1 in the open state is the third
As shown in FIG. 4, provided on the front side of the figure, the other ends of the links 2 and 3 pivotally and slidably supported at one end are pivotally attached to the blocks B1 and B2. , Link 2
The pin 4 is provided in the middle portion of the pin so as to project toward the back side of the paper surface, and the end of the link 3 is provided with a notch 3a for inserting the pin 4 and a rotation preventing bent portion 3b toward the front side of the paper surface. . When the lid is opened, the bent portion 3b contacts the link 5, and
The pin 4 is fitted into the notch 3a to position the links 2 and 3 in a straight line and support the block B1. In addition, hook 5
The block B1 blocks the opening movement of the block B1 and is attached to the block B1 in a rotatable and biased clockwise direction so that it can be engaged with and disengaged from a pin 6 projecting from the block B2. ing. The opening of the block B1 cannot be performed without releasing the engagement between the hook 5 and the pin 6.

The block B1 is provided with an exposure optical unit 100 for generating a scanning beam, and the block B2 is provided with an exposure optical unit 1.
An image forming unit 200 is provided which receives a beam generated by the photosensitive member 00 to develop an electrostatic latent image on the photosensitive member and transfers the electrostatic latent image to a recording sheet.
The block B3 is provided with a control unit 300 including the image forming unit 200 for performing various sequence controls. In the exposure optical unit 100, 31 is a semiconductor laser driven by a laser driving circuit (not shown), 32 is a collimator lens that makes the laser beam emitted from the semiconductor laser 31 a substantially parallel beam, and 33 is a cylindrical lens that receives the light transmitted by the collimator lens 32. It is a lens. The light emitted from the cylindrical lens 33 is reflected by the mirror 34 and enters the polygon mirror 35. The polygon mirror 35 deflects the incident beam in the main scanning direction (direction A), and the reflected light here passes through the fθ lens 36 and passes through the polygon mirror 3.
The light enters the cylindrical lens 37 for correcting the tilt angle error of the reflection surface of No. 5. Reference numeral 38 is a mirror that sends out the light transmitted through the cylindrical lens 37 as a scanning beam to the image forming unit 200 below in FIG. This exposure optical unit 100
All the optical components 31 to 38 constituting the above are mounted on a substrate 39, and the substrate 39 is elastically supported in the block B1. As shown in FIG. 1 and FIG. 2, this support mechanism includes a stepped support pin 55 having a small diameter portion 55a, a mounting hole 39a of a substrate 39 and an upper hole 56a of a support frame 56 of a main body (block B1). Slidably inserted in the mounting hole 39
The compression spring 57 is fitted into the small diameter portion 55a located between the upper hole 56a and the upper hole 56a, and the retaining ring 58 prevents the compression spring 57 from coming off.
Is slidably inserted into the prepared hole 56b of the support frame 56. The lower end of the large diameter portion 55b of the support pin 55 is in contact with the upper surface of the support frame 59 of the block B2 and is normally in the state of being moved to the position shown by the chain double-dashed line in FIG. The supporting means having the above structure is provided at the supporting points at the four corners of the instruction frame 56. In the exposure optical unit 100, the semiconductor laser 31 and the collimator lens 3 are most susceptible to the mechanical distortion.
It is a gap with 2. The collimator lens 32 has a focal length of several mm and a depth of focus as small as several μ. Therefore, it is necessary to ensure accuracy.

In the image forming unit 200, reference numeral 41 denotes a photoconductor package, which includes a driving roller 42, a driven roller 43, and a guide frame 44.
And a belt-shaped photoconductor 45 wound between the rollers 42 and 43. Sub-scanning is performed by rotationally driving the photoconductor 45 in the clockwise direction of FIG. 3 by the drive roller 42, and main scanning is performed by moving the beam generated by the exposure optical unit 100 in the widthwise direction of the photoconductor 45. Done. Reference numeral 46 is a magnetic brush type developing device provided with a developing roller 47, and 48 is a transfer electrode for transferring the toner image visualized by the developing device 46 onto a transfer sheet. The transfer paper in the cassette (not shown) set in the cassette insertion port 51 is sent to the transfer electrode 48 by the paper feed roller 49 and the transport roller 50. In this embodiment, the transfer sheet after passing through the transfer electrode 48 is sent to the thermal fixing device 52 in the block B1, and the sending roller 53 sends the transferred transfer sheet to the outside of the laser printer. Since the image forming unit 200 forms an image by an electrophotographic process, it is also provided with a charging electrode that charges the photoconductor 45 and a cleaning device that removes residual toner on the photoconductor 45 after transfer. However, it is omitted in FIG.
The various rollers described above are driven to rotate by a motor 54. The image forming unit 200 is supported by a support member (support frame 59 in FIG. 2) in the block B2, and the photoconductor package 41 and the developing device 46 can be easily taken out from the block B2.

The control unit 300 is fixed to the block B3 (bottom plate 57) and controls the drive of the laser drive circuit based on the print data sent from the external device and the electrophotographic process.

Since the printing operation in the above embodiment is similar to that of a normal laser printer, the description of the operation will be omitted and the support of the substrate will be described. When the block B1 is at the position indicated by the chain double-dashed line in FIG. 4, the support pin 55 is axially biased by the action of the compression spring 57 and is in the position shown by the solid line in FIG. However, when the lid is closed at the position indicated by the solid line in FIG. 4, the lower end of the support pin 55 is pushed by the support frame 59 of the block B2, and the lower end of the support pin 55 is in contact with the upper surface of the support frame 59. In position. The substrate 39
Support pin 5 by compression spring 57
It is constantly pressed against the stepped portion of No. 5. According to this supporting method, the relative positional relationship between the substrate 39 and the supporting frame 59 of the block B2, rather than the supporting frame 56 of the block B1, is accurately maintained, so that relative displacement with the photosensitive pair 45 or the like occurs. It is convenient. The substrate 39 is the main body (supporting frames 56, 59)
Since it is elastically supported without being fixedly attached to
The distortion of the main body rarely affects the substrate.

The present invention is not limited to the above embodiment. For example, the support pin 55 may be made of the same diameter, and a retaining ring may be fitted in the middle portion to form a step.

(Effect of the Invention) As described above, according to the present invention, even if distortion occurs in the block that houses the exposure optical unit with a simple configuration, the board in this block hardly distorts. Even with an inexpensive structure (a structure that is not robust), the positional relationship between the optical components of the exposure optical unit does not shift, and the positional relationship between the exposure optical unit and the image forming unit (photoreceptor) does not shift. It is possible to realize a laser printer having a simple mounting structure that does not occur.

[Brief description of drawings]

FIG. 1 is a block diagram of an exposure optical section in one embodiment of the present invention, FIG. 2 is a sectional view taken along the line II--II of FIG. 1, FIG. 3 is a general block diagram of the above embodiment, and FIG. It is a figure which shows the other operating state of an example. 1 ... Hinge, 2, 3 ... Link 4, 6 ... Pin, 5 ... Hook 31 ... Semiconductor laser, 35 ... Polygon mirror 36 ... f.theta. Lens 37 ... Cylindrical lens 38 ... Mirror, 39 ... ... Substrate 41 ... Photoconductor package 42 ... Drive roller, 45 ... Photoconductor 46 ... Developing device, 47 ... Developing roller 48 ... Transfer electrode, 52 ... Fixing device 55 ... Support pins, 56, 59 ...... Support frame 57 ...... Compression spring 58 ...... Retaining ring, 100 ...... Exposure optical unit 200 ...... Image forming unit, 300 ...... Control unit B1, B2, B3 ...... Block

Claims (1)

[Scope of utility model registration request] 1. A first block provided with an exposure optical section for generating a scanning beam modulated based on print data receives a scanning beam generated by the exposure optical section on a photosensitive member and electrostatically absorbs the scanning beam. In a laser printer attached to a second block provided with an image forming unit for visualizing an image using a developer and transferring the image onto a transfer sheet, the laser printer is attached by a hinge so that the lid can be moved. Each optical component is arranged on the same substrate in the first block, and one end of the support frame of the first block is provided so as to be able to contact the support frame of the second block. A plurality of stepped support pins that are slidable in the axial direction within a certain range are provided, and the stepped portions of the support pins are provided with respective optical components of the exposure optical section from the side opposite to the second block. Abutted substrate, and spring the substrate. With the support pin is a laser printer, characterized in that it has urged in a direction such as to protrude into the second block side.