JPH0381785A - Electrophotographic device - Google Patents

Abstract

PURPOSE:To improve writing accuracy by providing a lower main body with a lens supporting frame, and also providing it with a photosensitive body frame which positions the lens supporting frame when an upper main body presses the lens supporting frame. CONSTITUTION:An image forming unit case 33 is provided with a lens holding part 33c above th photosensitive body frame 31; a surface tilt correcting lens 49 for an optical writing means is inserted into the lens holding part 33c. When an opened device main body 10 is closed by means of its upper main body 10b, the image forming unit case 33 is pressed by the upper main body 10b via an elastic member 12. As it does so, the bottom of the lens holding part 33c of the pressed image forming unit case 33 abuts on the top end 50 of the side plate 31a of the photosensitive body frame 31, and consequently the upper main body 10b presses the top end 50. Thus, the image forming unit case 33 can be positioned by the photosensitive body frame 31. Thus, the surface tilt correcting lens 49 can be positioned in relation to a photsensitive body 13.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an electrophotographic apparatus, such as a printer, a copying machine, or a facsimile machine using a laser, which records on paper by repeating an electrophotographic process. In particular, the present invention relates to an electrophotographic apparatus in which the main body of the apparatus is divided into upper and lower parts.

This type of electrophotographic device is constructed by dividing the main body into a lower main body and an upper main body in order to remove jammed paper and replace parts, and the upper main body can be opened and closed with respect to the lower main body. shall be. The lower body is equipped with a photoreceptor, and the upper body is equipped with an optical writing means, and the light from the light source of the optical writing means passes through an optical component such as a lens and forms an image on the photoreceptor, thereby forming an image on the photoreceptor surface. Write to.

Problem to be Solved by the Invention However, in this split-type electrophotographic apparatus, the photoreceptor and the optical writing means are arranged separately, and the relative position of the two is determined via several other parts. There has been a problem in that the positional accuracy of the optical writing means cannot be accurately achieved with respect to the recording medium, and the relative position thereof shifts, resulting in poor writing accuracy and, as a result, recording quality.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to accurately position an optical writing means with respect to a photoreceptor in the above-mentioned electrophotographic apparatus.
The objective is to improve writing accuracy and recording quality.

Means for Solving the Problems Therefore, in the present invention, for example, as shown in the illustrated embodiment below, the device main body 10 is divided into a lower main body 10a and an upper main body 10b.
The upper main body 10b can be opened and closed with respect to the lower main body 10a, and the lower main body LOa is provided with a photoreceptor 13, while the upper main body 10b is provided with an optical writing means 14, and the light The light from the light source of the writing means 14,
For example, in an electrophotographic apparatus that forms an image on the photoreceptor 3 through a lens such as a lens 49 for correcting surface tilt and writes on the surface of the photoreceptor 13, the lens is supported and the lower body 10a is When the upper body part ○b is closed, a lens support frame such as the drawing unit case 33, which is held by the upper body 10b, is held by the lower body 10a.
Along with preparing for.

It is characterized by comprising a photoreceptor frame 31 that supports the photoreceptor 13 and positions the lens support frame when the upper body 10b presses the lens support frame.

Operation Then, the upper body 10b is closed with respect to the lower body 10a, the lens support frame is held down by the upper body 10b, and the lens support frame is positioned by the photoreceptor frame 3.

As a result, light from the light source of the optical writing means 14 passes through the lens and forms an image on the photoreceptor 13, thereby writing on the surface of the photoreceptor 13.

Example Hereinafter, the present invention will be described in detail with reference to the drawings.

' FIG. 6 shows a laser printer which is an embodiment of the present invention. The reference numeral 10 in the figure is the main body of the apparatus.

The device body 10 is divided into a lower body 10a and an upper body 10b, and the upper body 10b can be opened and closed with respect to the lower body 10a. On the right side of the lower main body 10a in the figure, there is a paper feed tray 1.
1 is detachably attached.

The upper body 10b is provided with an elastic member 12 such as a spring as shown in FIG.

The internal mechanism of this laser printer is schematically shown in FIG. First, the photoreceptor 13 is placed in the lower body 10a, and the optical writing means 14 is placed in the upper body 10b, and the photoreceptor 13 and the optical writing means 14 are inserted into each of the upper and lower bodies 10.
Separate into b and loa. Furthermore, the lower body 10a
Inside, in addition to the photoreceptor 3, charging means 15, developing means 16, and so on are arranged clockwise in the figure around the photoreceptor 3. Transfer means 17. Cleaning means 8 etc. are arranged. Then, the photoreceptor 13 is rotated in the clockwise direction shown by the arrow in the figure, the upper surface of the photoreceptor 3 is charged, and an electrostatic latent image is formed on the photoreceptor 13 by irradiating the laser beam with the optical writing means 14. , the latent image is transferred to the developing means 16
Develop and visualize. Next, this visible image is transferred onto the paper 20 fed from the paper feed tray 11 by the transfer means 17.

Further, after the transferred image is thermally fixed by the fixing means 21, the paper 20 is stacked on the paper discharge tray 22.

Incidentally, the above-mentioned photoreceptor 13 is housed in an image forming frame 25 together with the developing means 16 and the image forming unit 24, as shown in FIG. The image forming frame 25 is formed into a box shape surrounding one periphery, and has a pair of opposing side plates 26 and 2.
7 into a U-shape and sequentially attach bearing parts 26a, 27a, 2.
6b-27b, 26c and 27c are provided. A mounting shaft 30 projects from one side plate 28 of the other pair of side plates 28 and 29. The image forming frame 25 is installed in the lower main body 10a so as to be rotatable about the mounting shaft 30.

As shown in FIG.
Hold at 1. The photoreceptor frame 3 has a support shaft 32
It consists of both side plate parts 31a through which the two side plate parts 31a pass, a handle 31b provided between the both side plate parts 31a, and a bifurcated leg part 31c extending downward from the outer peripheral surface of the photoreceptor 13 from the first side plate part 31a.

The photoreceptor 13 then supports its support shaft 32 at the bearing portion 26b.
- It is engaged with 27b and supported by the image forming frame 25 so that it can be taken out. On the other hand, when the photoreceptor 13 is taken out and placed on an appropriate table, it is supported by the photoreceptor frame 31. Therefore, at this time, the photoreceptor 13 does not touch the table or roll on it.

The drawing unit 24 includes a drawing unit case 33 that includes a toner cartridge section 33a that is part of the developing means 16 and supplies toner thereto, and a waste toner storage section 33b that collects toner scraped off by a part of the cleaning means 18.
The charging means 15, cleaning means 18, etc. are built in.

Similarly to the photoreceptor 13 and the developing means 16, the support shaft 34
are engaged with the bearings 26a and 27a and supported by the image forming frame 25 so as to be removable.

On the other hand, the optical writing means 14 provided on the upper body lOb is
The optical scanning system is configured as shown in the figure.

That is, a laser beam emitted from a semiconductor laser 40 that is a light source is converted into a parallel beam by a collimating lens 41, shaped by an aperture 42, and then transformed into a parallel beam by a first cylindrical lens 43.
A rotating polygon mirror (deflector) 4 that rotates at a constant high speed through
It is incident on the mirror surface of 4. The reflected light is deflected within a predetermined angle range for each surface due to the rotation of the mirror surface,
Scan the same angular range repeatedly. This laser light passes through the f-theta lens 45 so as to form an image in a straight line on the circumferential surface of the photoreceptor 13 at a constant speed, and a part of it is reflected by the mirror 46 and reaches the synchronization detection device 47. , others are mirror 48,
The image is formed on the photoreceptor 13 via the surface tilt correction lens 49.

This surface inclination correction lens 49 is for correcting optical path deviation due to inclination of each mirror surface of the deflector 44.

By the way, as shown in FIG. 1 (the upper body is shown in an open state), the drawing unit case 33 is provided with a lens holding portion 33c above the photoreceptor frame 31. The lens holding portion 33c is formed into an elongated shape parallel to the support shaft 32 on the photoreceptor 3. The drawing unit case 33 inserts, in particular, the surface tilt correction lens 49 of the optical writing means 14 into and out of the lens holding portion 33c, and supports the lens 49 to form a lens support frame.

When the upper body 10b is closed from the open state of the apparatus body 10 shown in FIG. 6, the upper body lob presses the drawing unit case 33, which is a lens support frame, through the elastic member 12. At this time, as shown in FIG.
and presses its upper end surface 50 with the upper body 10b. As a result, one drawing unit case 33 is positioned with respect to the photoreceptor frame 31. Therefore, the tilt correction lens 4
9 is positioned with high accuracy with respect to the photoreceptor 13. In addition, in this illustrated embodiment, since the one-sided tilted lens 49 is held in the lens holding portion 33c so as to be freely inserted and removed, regardless of the timing of replacing the entire drawing unit 24,
When this lens becomes dirty, only that lens can be appropriately taken out and cleaned.

By the way, in the illustrated embodiment described above, as shown in FIG. 2, the upper end surfaces 50 of the both side plates 31a of the photoreceptor frame 31 are shaped as flat surfaces, and the lens holding section 33c is pressed against the upper end surfaces 50. Place the tilt correction lens 49 on the photoconductor 1.
Position against 3.

However, in the case of this configuration, as shown in FIGS. 3(a) and 3(b), for example, a part of the upper end surface 50 is cut out to form a stepped portion 50a, and a lens holding portion is formed in the stepped portion 50a. 33c can also be configured to engage. In FIG. 3(a), the movement of the drawing unit case 33 is restrained not only in the vertical direction but also in the horizontal direction. Also,
Instead of engaging the lens holding portion 33c with both side plate portions 33a of the photoreceptor frame 31, for example, a fourth
As shown in the figure, a fitting hole is made in the lens holding part 33c,
On the other hand, a protrusion 5 protruding from the upper end tube 50 is provided on both side plate portions 31a.
0b may be provided and the protrusion 50b may be fitted into the fitting hole.

Further, in the illustrated embodiment described above, the drawing unit case 33 is used as the lens support frame. However, the lens support frame is not limited to one image forming unit case, but can also be constructed using, for example, the above-mentioned image forming case, which is provided around the photoreceptor.

Further, in the above-described illustrated embodiment, the lens to be positioned is configured with the surface tilt correction lens 49. However, the lens may be any other lens as long as it is used in the optical writing means. In addition, in this invention,
This is not limited to the case where only such a lens is supported by a lens support frame. For example, the lens may be supported together with other optical components such as the mirrors 46 and 48 by a lens support frame and positioned relative to the photoreceptor. can.

In this invention, for example, as shown in FIG. 5, an arm 60 is rotatably attached to the lens holding part 33c, and the other end of a spring 61 with one end attached to the lens holding part 33c is attached to the arm 60. It is also possible to provide the arm 60 with a habit of always rotating clockwise in the figure, and to hook the hook portion 60a of the arm 60 onto the shaft 62.

Therefore, according to the present invention, in an electrophotographic apparatus in which the apparatus main body is divided into upper and lower parts as described above, the lens of the optical writing means is supported by the lens support frame in the lower main body, and the lens Since the support frame is positioned by the photoreceptor frame, the lens of the optical writing means can be accurately positioned with respect to the photoreceptor, writing accuracy can be improved, and recording quality can be improved.

[Brief explanation of drawings]

FIG. 1 is a schematic cross-sectional view showing the configuration for supporting the surface tilt correction lens of the optical writing means when the device main body of a laser printer according to an embodiment of the present invention is opened, and FIG. FIGS. 3A and 4B are schematic sectional views showing other embodiments of the positioning structure, respectively. FIGS. FIG. 3(B) is a partial perspective view showing the shape of the upper part of the photoreceptor frame in the positioning structure shown in FIG. 7 is a perspective view showing the laser printer according to the present invention in an open state, FIG. 7 is a schematic configuration diagram showing the internal mechanism of the laser printer, and FIG. 8 is an image forming case of the laser printer and its image forming case. FIG. 9 is an exploded perspective view showing the electrophotographic processing means housed in the laser printer, and FIG. 9 is a configuration diagram of the optical scanning system of the optical writing means of the laser printer. α...Laser light (light) 10...Device main body 10a...Lower main body 10b...Top Main body 13...Photoconductor 14...Optical writing means 31...Photoconductor frame 33...
・・・・Picture unit case (lens support frame)

Claims (1)

[Scope of Claims] The main body of the apparatus is composed of a lower main body and an upper main body, the upper main body and the lower main body can be opened and closed, the lower main body is provided with a photoreceptor, and the upper main body is provided with a photoreceptor. In an electrophotographic apparatus that includes an optical writing means and forms an image of light from a light source of the optical writing means on the photoreceptor through a lens and writes on the surface of the photoreceptor, the lower body supports the lens and The lower body includes a lens support frame which is pressed by the upper body when the upper body is closed, and which supports the photoreceptor and which supports the lens support frame when the upper body presses the lens support frame. An electrophotographic device comprising a photoreceptor frame for positioning.