JPH0412509Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention provides an image forming apparatus that has an upper housing and a lower housing, and the upper housing can be opened and closed relative to the lower housing around a support shaft. It is related to.

[Prior art and its problems]

There are image forming apparatuses that perform correct image forming operations only when a functional unit including a photoreceptor is removably attached to the main body of the apparatus. In such an image forming apparatus, if the main body of the apparatus is operated without any functional unit installed, it will malfunction. In order to prevent this malfunction, conventionally, if the functional unit is not properly set, the case, etc. will not close because the functional unit itself or the lock part will hit when closing. It had been. If you try to close the casing forcibly when the functional unit itself is against it,
There is a problem that the device itself is damaged or the functional unit is damaged, and if the lock portion is used as a butt, there is a problem that the lock portion, the casing, etc. are damaged.

[Purpose of invention]

In view of the above-mentioned drawbacks of the conventional devices, the present invention has been developed so that when the functional unit is not installed in the predetermined position, even if the casing, etc. is closed, the functional unit, the lock part, the casing, etc. will not be destroyed. The object of the present invention is to provide an image forming apparatus that is not damaged.

[Key points of the idea]

In order to achieve the above object, the present invention includes a lower casing, an upper casing that can be opened and closed with respect to the lower casing around a horizontal axis, and a function that can be freely attached and removed inside the lower casing or the upper casing. a unit, and a lock portion that can be engaged with the lower housing and the upper housing, respectively,
In the image forming apparatus, the locking mechanism locks the two housings in the closed position by locking the locking portions together when the two housings are closed, wherein the locking mechanism locks the two housings in the closed position. moving means for moving the lock parts to an engagement position where they can be locked to each other and a non-engagement position where they cannot be locked, depending on the mounting state of the functional unit; By being moved to the possible position, both the casings are locked in the closed position only when the functional unit is installed and both the casings are closed.

[Example of idea]

An embodiment of the present invention will be described using a printer that applies electrophotographic technology as an example.

FIG. 5 is a schematic configuration diagram showing the entire printer according to the present invention.

A photosensitive drum 2 located approximately at the center of the printer 1 includes a photoconductor layer and rotates in the direction indicated by an arrow X.

The surface of the photoreceptor drum 2 is uniformly charged by the charger 3, and then an image information exposure section 4 performs exposure based on image information to form an electrostatic latent image on the surface of the photoreceptor drum 2. Thereafter, the electrostatic latent image is developed with toner by the developing device 5 to make it visible. On the other hand, the paper fed by the paper feed roller 7 from the paper feed cassette 6 disposed at the lower part is conveyed by the paper feed roll section 8, and is further formed on the photoreceptor drum 2 and is exposed by the toner development. The image is conveyed by a standby roll 9 in synchronization with the imaged image, and the image is transferred by a transfer device 10, and then transferred to a fixing device 11.
The image is fixed on the paper and is ejected onto the paper ejection tray 12.
Also, the residual toner on the photoreceptor drum 2 is removed by the cleaner 1.
3, the surface of the photoreceptor drum 2 is uniformly charged by the charger 3 in preparation for the next image formation.

The main body of the printer 1 includes an upper housing 14 and a lower housing 1.
5, and the upper housing 14 can be opened and closed around a support shaft 16 of a hinge portion. A first functional unit 17 is integrally formed with at least one of the photoreceptor drum 2, the charger 3, the developer 5, the transfer device 10, and the photoreceptor drum 2 in the cleaner 13. is the second functional unit 18
The first functional unit 17 and the second functional unit 18 are detachably installed in the main body of the printer 1 from above in a so-called shell open state in which the upper housing 14 is opened and closed.

When the printer 1 is normally used, the first functional unit 1
7 and a second functional unit 18 are mounted in predetermined positions, and the upper housing 14 is locked to the lower housing 15 in a closed state, so-called shell-closed.

FIGS. 1 and 2 are side views of a locking member 19 that locks the first functional unit 17 and a locking mechanism that locks the upper housing 14 and the lower housing 15, and shows shell-closed and shell-opened shells, respectively. Indicates the state in which

The lower housing 15 accommodates the drum shaft 2 of the photosensitive drum 2.
A slit portion 1 along the vertical direction at a position corresponding to a
5a, the lower end of a compression spring 20 is locked near the support shaft 16 of the hinge portion, and a trapezoidal lock member 21 is fixed to the upper inner surface on the front side.

The locking member 19 has a plate-shaped vertical part 19a and a horizontal part 19b orthogonal to the lower end of the vertical part 19a, and the vertical part 19a projects from the upper end of the lower housing 15.
A stepped portion 19c is formed substantially flush with the upper end of the lower housing 15, and one end of the horizontal portion 19b is rotatably attached to the upper portion of the lower housing 15 near the support shaft 16 with respect to the drum shaft 2a. , a small stepped portion 19 is provided on the other end side of the horizontal portion 19b.
d, and a semicircular recess 19e into which the drum shaft 2a fits is formed at the lower end.

The locking member 22 includes a vertical portion 22a and a vertical portion 22a.
The lower end of the vertical part 22a is rotatably attached to the lower housing 15, and one end is fixed to the lower housing 15 at the upper end of the vertical part 22a. The other end of the tension spring 23 is connected and biased to rotate clockwise in FIGS. 1 and 2. Lateral portion 22b of lock member 22
The distal end thereof engages with the small stepped portion 19d of the locking member 19, and a curved surface 22c is formed at the upper portion to form a tapered profile.

The horizontal link 24 is attached to the shaft 1 near the front of the upper housing 14.
The upper end of a tension spring 25, the lower end of which is fixed to the lower part of the upper housing 14, is connected to the distal end of the tension spring 25, which is rotatably attached by the drum shaft 4a and extends from the position of the drum shaft 2a to the rear side.

The vertical link 26 is connected to the locking member 1 in FIG.
9, the upper end is pin-jointed to the horizontal link 24, and the lower part is slidably guided in the vertical direction by a guide 27 fixed to the lower part of the upper housing 14 to prevent lateral movement. is restrained, and the lower end is the locking member 1
9 is in contact with the upper end of the vertical portion 19a.

The vertical link 28 has an upper end pin-jointed to the front end of the horizontal link 24, and has a vertical hole 28a in the middle, and a headed pin 14b fixed to the upper housing 14 can freely slide into the vertical hole 28a. It is inserted through the tube and its lateral movement is restricted. Further, the vertical link 28 has an inclined surface 28b and a stepped portion 28c formed at the lower end,
The stepped portion 28c engages with a trapezoidal lock member 21 fixed to the upper part of the lower housing 15.

Next, the operation of the locking member 19 and locking mechanism of the present invention having the above configuration will be explained. As shown in FIG. 2, with the shell open, the locking member 19 is manually rotated in the direction shown by arrow A to open the drum shaft 2a, and the drum shaft 2a is inserted into the slit portion 1 of the lower housing 15.
Insert the photosensitive drum 2 until it reaches the bottom of 5a.
Thereafter, the locking member 19 is rotated in the direction shown by arrow B to fit the drum shaft 2a into the recess 19e of the locking member 19, and the small stepped portion 19d is locked into the locking member 2.
hook on the tip of the horizontal part 22b of 2. At this time, if the first functional unit 17 including the photosensitive drum 2 is not set in the correct position, the locking member 19 will not be caught by the locking member 22. Therefore, depending on whether the locking member 19 is caught on the locking member 22 or not, it is possible to detect whether the first functional unit 17 is set correctly or incorrectly.

Also, when the first functional unit 17 is in the normal position, when the shell is closed from the shell open,
As shown in FIG. 1, the lower end of the vertical link 26 touches the upper end of the vertical portion 19a of the locking member 19, and the guide 2
7 and pushes up, and moves to push up the joint with the horizontal link 24. By this operation, the vertical link 28 is lowered to a predetermined position, and the stepped portion 28c at the tip catches the lower surface of the trapezoidal locking member 21, locking it and simultaneously closing the shell. In this case, the relationship between the stroke of the vertical link 26 and the stroke of the vertical link 28 is
6 is pushed up by the locking member 19 and the vertical link 2
8 is a trapezoidal lock member 21 only when moving downward.
The step portion 28c at the lower end is set so as to be caught by the step portion 28c. When the first functional unit 17 is not attached, the locking member 19 cannot be held in the state shown in FIGS. 1 and 2, and since there is no support from the drum shaft 2a, the tension spring 25 Since the vertical link 26 is urged downward through the vertical link 26, the vertical portion 19a is pushed down, so the vertical link 28 does not descend as shown in FIG. Since the lower end of the member 21 cannot be reached, it cannot be hooked, and the upper housing 14 is opened by the biasing force of the compression spring 20 and the shell is not closed.

FIGS. 3 and 4 are side views of another embodiment of the present invention, showing the shell closed state and shell open state, respectively. In this case, the upper case 14 and the lower case 15 are different from the case of the above embodiment.
The relationship between the two is completely reversed, the locking member 19 and the locking mechanism themselves are the same, and there is no fundamental difference in operation, so a description thereof will be omitted.

In the above embodiment, the locking member 19 of the first functional unit 17 including the photosensitive drum 2 is
Although only the fixing member 19 and the locking mechanism are shown, the second functional unit 18 including the fixing device 11 can also be provided with a similar locking member 19 and locking mechanism.

[Effect of idea]

According to the present invention, a functional unit is removably installed in a device main body having an upper housing and a lower housing that can be opened and closed around a support shaft, and the functional unit is engaged with a locking member. The upper and lower casings can be locked by the locking mechanism only when the unit is stopped, so even if the upper casing is closed when the functional unit is not installed in the specified position, it will not function. The unit, the lock mechanism, and each of the above-mentioned casings are not damaged or damaged, and the functional unit includes at least one of a developer, a charger, a cleaner, a photoreceptor, and a transfer device, or a fixing unit. If the unit includes the image forming apparatus, it can be an economical and convenient image forming apparatus.

[Brief explanation of the drawing]

The drawings all relate to embodiments of the present invention, and FIGS. 1 and 2 are side views of the locking member and the locking mechanism, showing the shell closed and shell open states, respectively, and FIG. 3 4 is a side view of another embodiment, and FIG. 5 is a schematic configuration diagram showing the entire image forming apparatus. 1...Printer, 2...Photosensitive drum, 2a...
...Drum shaft, 3...Charger, 4...Image information exposure unit, 5...Developer, 6...Paper feed cassette, 7...
Paper feed roller, 8... Paper feed roll section, 9... Standby roll, 10... Transfer device, 11... Fixing device, 12...
Paper ejection tray, 13...cleaner, 14...upper casing, 14a...shaft, 14b...headed pin, 15...
...Lower housing, 15a...Slit portion, 16...Support shaft, 17...First functional unit, 18...Second
Functional unit, 19...Locking member, 19a...Vertical section, 19b...Horizontal section, 19c...Stepped section, 19d...
...Small portion, 19e...Concave portion, 20...Compression spring,
21... Trapezoidal lock member, 22... Lock member,
22a...Vertical portion, 22b...Horizontal portion, 22c...Curved surface, 23...Tension spring, 24...Horizontal link, 2
5... tension spring, 26... vertical link, 27...
Guide, 28... Vertical link, 28a... Vertical hole, 28b... Inclined surface, 28c... Step portion.

Claims (1)

[Scope of Claim for Utility Model Registration] (1) A lower casing, an upper casing that can be opened and closed about a horizontal axis relative to the lower casing, and a functional unit that can be attached and removed inside the lower casing or the upper casing. and, the lower housing and the upper housing are each provided with an engageable lock portion, and when both the housings are closed, the lock portions are engaged with each other, so that the both housings are placed in the closed position. In the image forming apparatus, the lock mechanism has an engagement position where the lock parts can be locked to each other and a non-engagement position where the lock parts cannot be locked, depending on the mounting state of the functional unit. The lock portion is moved to the engageable position when the functional unit is installed, so that only when the functional unit is installed and both the casings are closed. An image forming apparatus characterized in that both the housings are locked in a closed position. (2) The image forming apparatus according to claim 1, wherein the functional unit is a unit including at least one of a developer, a charger, a cleaner, a photoreceptor, and a transfer device. (3) The image forming apparatus according to claim 1, wherein the functional unit is a unit including a fixing device.