JPS62170979A - Electrostatic photographic device - Google Patents

Abstract

PURPOSE:To easily execute the maintenance of a developing device by coupling an upper frame with a lower frame so that both frames are freely opened and closed and attaching at least a photosensitive body, a developing part and a cleaning mechanism to a holding body to form a developing unit. CONSTITUTION:The developing unit is a consumable product and replaced at a fixed period. To replace the unit 27, an operation rod 74 is pressed from the front side and a suspension lever 71 is rotated in the clockwise direction to recede the lever 71 from a projection tip 45. Under said status, the upper frame 3 is opened upward around a supporting shaft 4. Under said status, a press lever 68 is displaced upward and the developing unit 27 is supported by notches 63-65. Thereby, the developing unit 27 can be drawn out to a wide external space by lifting a handle 42, and in the space, the exchange of the photosensitive body or the developing part can be extremely easily executed.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to an electrostatographic apparatus that develops an electrostatic latent image formed on the outer periphery of a photoreceptor and transfers the developed image to a medium such as paper.

2. Description of the Related Art A developing device in this type of electrostatic photographic apparatus has a developing section that visualizes the electrostatic latent image using toner, and a developing section that visualizes the electrostatic latent image with toner, on the outer periphery of the photoconductor on which the electrostatic latent image is formed, and a developing section that removes the remaining toner after transfer. A cleaning device for removing the photoreceptor from the outer periphery is provided. The photoreceptor, developing section, and cleaning mechanism that constitute the developing device are individually assembled.

Problems to be Solved by the Invention On the other hand, the photoreceptor, cleaning mechanism, and developing section are consumable items and are frequently replaced. However, as mentioned above, the photoreceptor, the developing section,
The cleaning mechanism must be disassembled one by one.

In the second type of work, the ease of maintenance is extremely poor because many other installed parts get in the way.

The present invention has been made in view of the above points, and an object of the present invention is to provide an electrostatic photographic apparatus whose developing device can be easily maintained.

Means for Solving the Problem A developing unit is provided in which an upper frame and a lower frame are connected in an openable and closable manner, and at least a photoreceptor, a developing section, and a cleaning mechanism are attached to a holder, and a pressing force provided on the upper frame is provided. The developing unit is positioned and held by the support section and the support section provided on the lower frame.

During operational maintenance, the developing unit can be attached or detached by rotating the upper frame upward relative to the lower frame. Therefore, the photoreceptor, cleaning mechanism, developing section, etc. can be replaced in a large work space.

Example An embodiment of the present invention will be described based on the drawings.

1 is a housing. The second housing 1 has a lower frame 2 and an upper frame 3, and the rear parts of the lower frame 2 and the upper frame 3 are rotatably connected around a support shaft 4 as a fulcrum. Further, clamps (not shown) are attached to the front portions of the lower frame 2 and the upper frame 3 so as to be releasably engaged with each other. A cassette case 6 that stores a large number of sheets 5 in a stacked state is detachably attached to the bottom of the lower frame 2 from the front, and this cassette case 6 has a guide plate 7 that changes the direction of the sheets 5 into a U shape and a manual feed tray. 8. A guide plate 9 facing the guide plate 7 and guiding the paper 5 degrees is held by the lower frame 2, and a guide plate 10 facing the rear of the guide plate 9 and guiding the paper 5 is held by the upper frame 3. .

The lower frame 2 also includes a paper feed roller 11 that pulls out the paper 5 in the cassette case 6, feed rollers 12 and 13 that transport the paper 5 to a photosensitive drum (described later), a transfer charger 14, and a transfer charger L4. A feed roller 16 that guides the sheet of paper 5 to the fixing device 15 is held. The fixing device 15 includes a pressure roller 17 that is detachably held on the lower frame 2 and a heating drive roller 18 that is held on the upper frame 3. Furthermore, the upper frame 3 includes a guide plate 19 that guides the paper 5 that has passed through the fixing device 15, feed rollers 21 and 22 that send the paper 5 to the paper receiver 2o, a light source section 23, a static charger 24, and a static elimination charger 2.
5 and a motor 26 are provided.

Next, a developing unit 27 is provided.

As shown in FIGS. 4 and 5, this developing unit 27 has a holder 29 holding a cleaning mechanism 28, and a photosensitive drum 3o as a photosensitive member and a developing section 31 detachably mounted thereon. . The cleaning mechanism 28 includes a sponge roller 33 housed in a toner reservoir 32, a blade 34 and mylar 35 that contact the photoreceptor 3o. The developing section 31 includes a toner box 37 containing toner 36 and a magnet roller 38. A shaft 39 is provided upright on both sides of the toner box 37 . U-shaped grooves 41 that rotatably hold the shaft portion 40 of the photosensitive drum 30 are formed on both sides of the holder 29 and are inclined upward toward the front, and arms 43 fixed to both ends of the handle 42 are fixed. has been done. These arms 43 are formed with U-shaped hooks 44 that position and support the shafts 39 from below that protrude from both sides of the toner box 37, and protrusions 45 that protrude outward.

Furthermore, levers 47 that support rollers 46 are rotatably held on both sides of the holding body 29, as shown in FIG. These levers 47 are elastic pieces 4 that bend elastically.
8, and is biased downward by abutting this elastic piece 48 against a part 49 of the holder 29. Projecting pieces 5o are formed on both sides of the front side of the holding body 29, and a lever 51 is rotatably attached to these projecting pieces 50.

One end of a release tape 53 is held by a hook 52 formed integrally with these levers 51.
A spring 54 is stretched between the other end and the lever 47.

As shown in FIG. 5, the rotation range of the lever 51 is determined to include a range that buffers the movement locus 55 of the outer periphery of the photosensitive drum 30 when the shaft portion 4o of the photosensitive drum 30 is removed from the groove 41. There is. In order to restrict the range of rotation, the lever 51 is formed with contact surfaces 56 and 57 that contact the edges of the protruding piece 5o. As shown in FIG. 6, the left and right rollers 46 have a small diameter portion 46a located at the center that applies tension to the release tape 53, and a portion located on both sides of this small diameter portion 46a between the feed roller 16. Large diameter portion 46 that holds paper 5
It has b.

Next, the mounting structure of the lever 47 is shown in FIG. A circular hole 5 is formed in the projecting piece 58 that protrudes from both sides of the bottom of the holding body 29.
9 and a notch 60 communicating with this circular hole 59 from the outside. A slot 62 is formed on the outer periphery of a shaft 61 that connects the left and right pair of levers 47 and is rotatably fitted into the circular hole 59. Therefore, by aligning the direction of the slot 62 with the notch 60, fitting the shaft 61 into the circular hole 59, and then rotating the lever 17, the shaft 61 is prevented from coming out of the notch 60.

Further, as shown in FIGS. 1, 2, and 3, U-shaped notches 63, 64, and 65 with an opening at the upper end, which are supporting parts for holding the developing unit 27, are formed on both sides of the lower frame 2. There is. The notch 63 positions and supports the shaft 39 protruding from both sides of the toner box 37, the notch 64 positions and supports the shaft 40 of the photosensitive drum 30, and the notch 65 positions the shaft 66 protruding from both sides of the holder 29. I'm supporting you.

A pressing lever 68, which is a pressing portion that is biased by a spring 67 and presses the shaft portion 40 of the photosensitive drum 30 downward, is rotatably held on the upper frame 3 about a shaft 69. A compression spring 70 is provided as a pressing portion for pressing the arm 43 downward, and a lifting lever 71 that engages with a protrusion 45 formed on the arm 43 is biased by a spring 72 and rotatably held by a shaft 73. Furthermore, an operating rod 74 for suppressing the lifting lever 71 is held slidably in the front-back direction.

In one section of the toner box 37, a gear 75 supported by the shaft 39, a gear 76, and a gear 77 fixed to the end of the magnet roller 38 are provided. The motor 26 transmits rotation to the magnet roller 38 via gears 75, 76° 77, and the feed roller 11.
, which drives the feed rollers 12, 16.22 and the heating drive roller 18.

In such a configuration, when an operation unit (not shown) is operated, the photosensitive drum 30 rotates once, and the paper 5 is supplied to the outer circumference of the photosensitive drum 30 in synchronization with this operation. In the process of one revolution of the photosensitive drum 3o, the charger 24
charges the outer periphery of the photosensitive drum 30 with a potential, this charged layer is scanned with a laser beam from the light source section 23 to form an electrostatic latent image, and the developing section 31 develops this electrostatic latent image to produce a developed image. The transfer charger 14 transfers the toner to the paper 5, the cleaning mechanism 28 removes the residual toner attached to the outer periphery of the photosensitive drum 30, and the static elimination charger 25 transfers the toner to the photosensitive drum 3.
Remove the potential around the 0. The transferred paper 5 is sent rearward by the feed roller 16 and the large diameter portion 46b of the roller 46, fixed by the fixing device 15, and discharged to the paper receiver 20.

During this time, the release tape 53 functions to release the paper 5 from the photosensitive drum 30 on both sides outside the printing range.

The developing unit 27 is a consumable item, and should be replaced at regular intervals.In that case, the operating rod 74 is first pressed from the front, the lifting lever 71 is rotated clockwise, and the developing unit 27 is retracted from the projection 45. In this state, the upper frame 3 is
is opened upward as shown in FIG. In this state, the presser lever 68 is also displaced upward, and the developing unit 27 is supported by the notch 63°64.65. Therefore, the handle 42
By lifting the developing unit 27, the developing unit 27 is taken out to a wide space outside, and the photosensitive drum 30 and developing section 31 are replaced at this position.

The cleaning mechanism 28 and the photosensitive drum 30 have approximately the same lifespan, and the developer gBx has a longer lifespan. In reality, when the cleaning mechanism 28 deteriorates, the photosensitive drum 30 also deteriorates, and the developing section 31 is removed and discarded together with the holder 29.

The developing section 31 can be disassembled simply by removing the shaft 39 from the hook 44, and the photosensitive drum 30 can be disassembled simply by removing the shaft 40 from the groove 41'X. Therefore, the photosensitive drum 30 and the developing section 31 can be attached and detached very easily in a wide working space without using any tools. Note that the developing section 31 attempts to rotate about the shaft 39, but in order to keep the distance between the magnet roller 38 and the photosensitive drum 3o constant, the photosensitive drum 3o is attached to the end of the magnet roller 38.
Since a ring (not shown) is provided that contacts the end of the 0, it does not actually rotate and remains stable. Since the developing unit 27 is positioned and supported by the notches 63, 64, 65 and pressed by the pressing lever 68 and the compression spring 7o, it can be stably installed in the housing 1 and the installation work is easy.

Effects of the Invention Since the present invention is constructed as described above, the developing unit can be reliably and easily held in a stable position by the supporting portion of the lower frame and the pressing portion of the upper frame, and the upper frame can be held upwardly. By opening it up, the developing unit can be taken out to a large external work space and the photoreceptor, developing section, etc. can be replaced very easily.

[Brief explanation of drawings]

The drawings show one embodiment of the present invention, and FIG. 1 is a longitudinal sectional side view showing the upper frame in a reduced state with the upper frame opened upward, and FIG. 2 is a reduced longitudinal side view showing the state in which the upper frame is closed downward. FIG. 3 is a side view showing the support structure of the developing unit; FIG. 4 is a vertical side view showing the developing unit;
Fig. 5 is a side view showing the state in which the photosensitive drum is removed from the holder, Fig. 6 is a partially enlarged perspective view showing the holding structure for the release tape, and Fig. 7 is a lever that holds the rear end of the release tape. FIG. 3 is a partially enlarged longitudinal sectional side view showing the mounting structure of the FIG. 2...Lower frame, 3...Upper frame, 4...
Support shaft (fulcrum), 27...Developing unit, 28...Cleaning mechanism, 29...Holding body, 30...Photosensitive drum (photosensitive member), 31...Developing section, 63-65 - Notch (
support part), 68...pressing lever (pressing part), 70...
・Compression spring (pressing part)

Claims (1)

[Claims] 1. The upper frame is connected to the lower frame so that it can be opened and closed in the vertical direction about a fulcrum and can be fixed at any position, and at least the photoreceptor, the developing section, and the cleaning mechanism are mounted on the holder. A developing unit is provided, the lower frame is provided with a support portion for positioning and detachably holding the developing unit in the vertical direction, and the upper frame is provided with a pressing portion for pressing the developing unit. Electrostatographic equipment. 2. The upper frame is connected to the lower frame so that it can be opened and closed in the vertical direction around a fulcrum and can be fixed at any position, and at least the photoreceptor and the developing section are removably attached to the holder that holds the cleaning mechanism. The static image forming apparatus is characterized in that a developing unit is provided, a support portion is provided on the lower frame for positioning and detachably holding the developing unit in the vertical direction, and a pressing portion for pressing the developing unit is provided on the upper frame. Electrophotographic equipment.