JPH0437973B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a body structure of an electrophotographic copying machine.
In conventional electrophotographic copying machines, a metal light shielding plate is attached to the upper part of the machine frame that houses the photosensitive drum and multiple process units, and the exposure optical system housing is formed by this light shielding plate and the upper part of the machine frame. A movable table for an exposure optical system is added to a guide rail fixed to the inner surface of the upper part of the body frame, and a document table glass is placed and fixed on the upper surface of the body frame.

Therefore, with such a conventional airframe structure,
Since various exposure optical system members are assembled to the body frame, the assembly line of the copying machine becomes extremely long, resulting in disadvantages such as increased equipment size and longer delivery times.

In addition, the light from the exposure lamp leaks through the gap between the metal plates, so work must be done to prevent this, and the heat in the exposure optical system housing is radiated to the circumferential surface of the photoreceptor drum through the metal plate light-shielding plate. As a result, the photoreceptor drum deteriorates early, and due to poor air convection within the exposure optical system housing, the inside of the exposure optical system housing becomes high temperature, causing various problems.

The present invention solves the above-mentioned problems on the assembly line of conventional copying machines,
The purpose of the present invention is to eliminate overheating in the exposure optical system housing and to greatly reduce the number of parts of the exposure optical system housing. A fuselage frame with an open upper part, and a light-shielding bottom wall mounted on the upper part of the fuselage frame, housing a projection lens inside, forming ventilation holes for the in-flight air flow passage around the periphery, and serving as a heat insulating plate at the bottom. an integrally molded deep-dish-shaped exposure optical system housing, an original table glass fixed to the upper part of the exposure optical system housing via a glass mounting plate, an exposure lamp and a scanning slit plate, and the exposure optical system a first movable table having both ends guided and supported by a pair of guide rail surfaces formed on opposing side walls of the system housing; and a first movable table formed on the exposure optical system housing in a state parallel to the guide rail surfaces. An electrophotographic copying machine is proposed that includes a second movable base on which a mirror is mounted that is guided and supported at both ends on another guide rail surface.

Embodiments of the invention will now be described in detail with reference to the drawings.

FIG. 1 is an exploded perspective view of the body of an electrophotographic copying machine according to the present invention, and FIG. 2 is a side sectional view of the completed electrophotographic copying machine.

The body frame A of the electrophotographic copying machine includes a pair of opposing end plates 1A and 1B, and these end plates 1A and 1B.
It is constructed into a box shape with its upper part open from a pair of side plates 2A and 2B assembled to 1B.

In the center of the fuselage frame A, there is a second
As shown in the figure, a photoreceptor drum 3 that is rotationally driven in the direction of the arrow is installed, and around the photoreceptor drum 3 there are a plurality of process devices adjacent to each other in the rotational direction of the drum, namely charging electrodes 4, magnetic A brush developing device 5, a transfer paper guide plate 6, a transfer separation electrode 7, a static elimination electrode 8, and a cleaning device 9 are arranged in an array, and these process devices are mounted in a frame 10 that can be pulled out from the machine frame A as shown in the first diagram. Can be assembled. In FIG. 2, reference numerals 11, 12, 13, 14, and 15 indicate a paper feed cassette, a paper feed roller, a conveyance roller, a fixing device, and a paper discharge roller device.

The side plates 2A and 2B have upper flanges 2a and 2b, respectively, which are bent at right angles to the inside of the fuselage frame A, and these upper flanges 2a and 2b are integrally molded in a deep dish shape with a heat insulating resin. The exposure optical system housing B is placed thereon. Although not limited to, this exposure optical system housing B is
First, an amount of foamed resin that is too small for the capacity of the mold cavity is injected into the cavity, then high-pressure gas is blown into the cavity to harden the surface resin of the mold cavity, and the high-pressure gas is removed to foam the internal resin. By employing the molding method, it is possible to obtain a housing with precise dimensions that is lightweight, highly insulating, and free from hot water sinks.

The exposure optical system housing B has a substantially rectangular bottom wall 1.
6, and a pair of end walls 1 surrounding the bottom wall 16 on all sides.
7A, 17B and side walls 18A, 18B,
These end walls 17A, 17B and side walls 18A, 1
8B has a large number of ventilation holes 19, and mounting screws 21 inserted into mounting holes 20 formed at the four corners of the bottom wall 16 are inserted into the upper flanges 2a, 2b.
The exposure optical system housing B can be fixed to the body frame A by screwing into the screw hole 22 of the housing B. Therefore, when the exposure optical system housing B is assembled to the body frame A, the ventilation hole 19 is connected to the space C between the body housing Y and the body frame A as shown in the second diagram, so that the exposure optical system housing Convection or blow-through of the in-machine wind occurs inside B, and overheating of the exposure optical system is prevented.

The bottom wall 1 of the exposure optical system housing B
A projection lens mounting seat 23 is integrally molded in the center of the projection lens 6, and a projection lens 24 is mounted to this projection lens mounting seat 23 using a "U"-shaped band 25. Further, a light-shielding box 26 rising upward is integrally formed in a portion near one end of the bottom wall 16, and the end face of this light-shielding box 26 on the opposite side from the projection lens 24 covers the circumferential surface of the photoreceptor drum 3. Mirror 2 oriented to
7 is fixed. In addition, a light-shielding box 2 with the bottom open
The lower surface of 6 is covered with a small light-shielding plate 29 having a slit 28 and removable.

both side walls 18A of the exposure optical system housing B;
The upper surface of 18B is a guide rail surface 34A, 34B on which both ends of the first movable base 33 to which the illumination lamp 30, mirror 31 and slit plate 32 are attached are placed.
On the guide rail surfaces 35 of the side walls 18A, 18B located internally lower than these guide rail surfaces 34A, 34B, there is a second movable platform having two mirrors 36, 37 at right angles. Both ends of 38 are guided and supported. Of course, the first movable base 3
3, the floating pulley 3 at the end of the second movable base 38
9. Fixed pulleys 4 at both ends of side walls 18A, 18B
A wire (not shown) is stretched between the relay pulley 42 at the intermediate portion of the side wall 2B, and this wire allows the first movable base 33 to move at a constant speed and the second movable base 38 is moved at 1/2 the speed of the first movable table 33.

On the other hand, both side walls 1 of the exposure optical system housing B
Three pairs of posts 4 stand up above both side walls 18A, 18B at both ends and middle part of 8A, 18B.
3A, 43B, 43C and 44A, 44B, 44
C is integrally molded. These posts have a horizontal upper surface or seat surface 45, and between these seats are the guide rail surfaces 34A, 34B and a pair of glass mounting plates 46A, 46 located above in a parallel direction.
B is fixed with screws 47 and these glass mounting plates 4
A document table glass D is mounted and fixed between 6A and 46B so as to cover the exposure optical system housing B from above.

Since the electrophotographic copying machine according to the embodiment has the above structure, the exposure optical system can be assembled on an assembly line completely separate from the machine frame A on which various process units are assembled. That is, the projection lens 24 and the mirror 27 are assembled to the exposure optical system housing B, and the first and second movable bases 33 and 38, which have been completed in advance, are mounted on the guide rail surface 34.
A, 34B, and 35 can be mounted on the exposure optical system housing B, and the exposure optical system housing B can be fixed to the body frame A with the mounting screws 21. Therefore, according to the present invention, the assembly line can be much shortened compared to the conventional one, and since the bottom wall 16 of the exposure optical system housing B has heat insulating properties, heat radiation from the bottom wall 16 can be used to protect the photoreceptor drum. Aircraft frame A does not deteriorate early.
Since the exposure optical system housing B having the ventilation hole 19 is mounted on the upper part of the exposure optical system housing B, air can easily pass through the inside of the exposure optical system housing, and the exposure optical system will not be overheated.

As a result, according to the present invention, by shortening the assembly line and using an inexpensive exposure optical system housing, it is possible to prevent early deterioration of the photoreceptor drum and prevent overheating of the exposure optical system.

Further, according to the present invention, after the first and second movable bases are assembled to the exposure optical system housing to be molded and the document table glass is fixed, the exposure optical system housing can be fixed to the machine frame. This has the effect of reducing the number of parts and streamlining the assembly line.

[Brief explanation of drawings]

FIG. 1 is an exploded perspective view of the body of an electrophotographic copying machine according to the present invention, and FIG. 2 is a side sectional view of the same copying machine. A... Aircraft frame, B... Exposure optical system housing, D... Original table glass, 16... Bottom wall, 19
... Ventilation hole, 24 ... Projection lens, 33 ... First
Movable base, 38...Second movable base, 46A, 46B...
...Glass mounting plate.

Claims (1)

[Claims] 1. A body frame that accommodates a plurality of copying process units and is open at the top, and a body frame that is mounted on the top of this body frame, houses a projection lens inside, and has ventilation holes formed around its periphery for internal air circulation. In addition, there is an integrally molded deep-dish-shaped exposure optical system housing having a light-shielding bottom wall that also serves as a heat insulating plate at the bottom, an original table glass fixed to the upper part of the exposure optical system housing via a glass mounting plate, an exposure lamp and a first movable table on which a scanning slit plate is mounted and whose ends are guided and supported by a pair of guide rail surfaces formed on opposite side walls of the exposure optical system housing; An electrophotographic copying machine comprising: a second movable base on which a mirror is mounted with both ends guided and supported by another guide rail surface formed in the exposure optical system housing.