JPH086468A - Image-forming device - Google Patents

Abstract

PURPOSE:To achieve a reduction in the cost and improvement in the operability of a movable cover without increasing an installation space. CONSTITUTION:A locking/releasing means 30 is composed of an engagement part 35 provided on a main body case 11, and a locking/releasing member 31 provided at the end 22F of the movable cover 21 and at the front of the main body case. This locking/releasing member 31 is composed of a pressed part 32 which is displaced backward when being pressed from front, and a hook part 33 which locks the movable cover 21 by being engaged with the engagement part 35 of the main body case 11 when the movable cover 21 is put in a closing position, and which releases the engagement with the engagement part 35 by being displaced when the pressed part 32 is pressed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus having a locking / releasing means capable of locking / unlocking a movable cover.

[0002]

2. Description of the Related Art A conventional configuration of an image forming apparatus is shown in FIG.
It shows in (B). In the figure, 11 is a main body case.
The main body case 11 includes a photoconductor and a developing device, and a process unit capable of forming a toner image on the surface of the photoconductor based on print data, and a transfer device capable of transferring the toner image onto a sheet sent from the paper feed cassette 72P. A built-in fixing device that can fix the transferred toner image on the paper.

The main body case 11 has a large opening at the top for convenience of attachment / detachment of the process unit, paper jam processing, and maintenance of built-in parts. The main body case 11 is provided with a movable cover 21 that can open and close the opening 12.

As shown in FIG. 5B, the movable cover 21 has a rear end portion 22R on the rear portion of the main body case 11 as a fulcrum 2.
It is mounted rotatably around 9 and is positioned at a position (closing position) for closing the opening 12 in a normal state for performing printing work and the like, and is locked by using the locking / unlocking means 30P. Has been stopped).

The locking / releasing means 30P includes a body case 11
Engaging portion 35P provided on the upper portion of the movable cover 21 and the push-type lock / release member 3 provided on the upper surface of the movable cover 21.
1P and. Lock release member 31
In a state where the hook portion 33P is not pressed from above, the hook portion 33P engages with the engaging portion 35P by the urging force of the spring 39 to lock (lock) the movable cover 21 in the closed position, and the pressing force F is applied from above. In the case of being engaged, the hook portion 33P and the engaging portion 35P are rotated around the support shaft 32a in the clockwise direction in FIG. 5B while resisting the urging force of the spring 39.
The engagement relationship with is released and the movable cover 21 is configured to be in a rotation free state.

The locking / releasing means 30P is shown in FIG.
As shown in (A) and (B), it may be provided on the lateral side surface 13 of the main body case 11. Such locking / unlocking means 30
At P, when the pressing force F is applied to the lock / release member 31P from the side, the hook portion 33P releases the engagement relationship with the engagement portion 35P while resisting the urging force of the spring 39,
The state in which the movable cover 21 is locked is changed to the rotation free state.

[0007]

[Problems to be Solved by the Invention]
In the image forming apparatus shown in (A) and (B), in order to open the movable cover 21 smoothly, the auxiliary spring 38 that constantly urges the movable cover 21 in the opening direction (arrow Q direction) is essential. Has become.

That is, if the auxiliary spring 38 is not provided, the hook portion 33P is disengaged from the engaging portion 35P when the lock / release member 31P is pressed by hand. When is released, the hook portion 33P engages with the engaging portion 35P again due to the biasing force of the spring 39. Therefore, the movable cover 21 is lifted and released while the lock / release member 31P is continuously pressed from above. However, if the force F pressing the lock / release member 31P is too strong, the movable cover 21 is difficult to open. On the contrary, when the pressing force F is too weak, the locked state of the movable cover 21 cannot be released, and it is difficult to open the movable cover 21 smoothly.

Therefore, when the lock / release member 31P is released, the movable cover 21 is opened such that the hook portion 33P is opened to a position where the hook portion 33P cannot engage with the engaging portion 35P. It is necessary to provide the auxiliary spring 38 that biases in the direction (Q direction).

As described above, in the image forming apparatus shown in FIGS. 5A and 5B, the auxiliary spring 38 and the mounting parts of the spring 38 must be provided, and it is difficult to meet the current cost reduction request. have. Further, when the lock / release member 31P is pushed and released from above, the movable cover 21 is opened to a grippable position by the urging force of the auxiliary spring 38, but the lock / release member 31P can be opened further to open the cover 21 further. A force must be applied in the upward direction opposite to the pressing, which makes it difficult to smoothly perform the opening operation.

Further, in the image forming apparatus shown in FIGS. 6A and 6B, although the auxiliary spring is not necessarily provided, the lock / release member 31P is pressed to the outside of the side surface 13 of the main body case 11 from the side. There is an inconvenience that the installation space becomes large because it is necessary to secure an empty space for operation.

In view of the above circumstances, it is an object of the present invention to provide an image forming apparatus capable of reducing the cost and improving the operability of the movable cover without increasing the installation space.

[0013]

According to another aspect of the present invention, there is provided a main body case having an opening, and a rear end of the main body case is rotatably supported so that the opening of the main body case can be opened and closed. In an image forming apparatus including a movable cover and locking / releasing means capable of locking and unlocking the movable cover at a closed position, the locking / releasing means is provided on the main body case. And a lock / release member provided at the end of the movable cover on the front side of the main body case, the lock / release member being displaced rearward when pressed from the front, and the movable member. When the cover is positioned at the closed position, it engages with the engaging part of the main body case to lock the movable cover, and when the pressed part is pressed, it displaces to engage with the engaging part. Locking part that can be released Characterized by being composed.

In the image forming apparatus according to the second aspect of the present invention, in addition, the direction of the rotational moment generated around the rotational axis of the movable cover by the pressing force applied to the pressed portion of the lock / release member is concerned. It is characterized in that it is provided in the same direction as the opening direction of the movable cover.

[0015]

In the invention of claim 1 having the above-mentioned structure, the lock
The pressed portion of the release member can be pushed from the front to release the engagement between the locking portion and the engaging portion, and while maintaining this state, the movable cover can be rotated by applying a force in the direction of opening the movable cover.
Therefore, it is not necessary to provide the auxiliary spring for urging the movable cover in the opening direction and its mounting component, and the cost can be reduced. Further, after the locking release operation of the movable cover, it is possible to smoothly shift to the opening operation.

Further, since the lock / release member is provided at the end of the movable cover on the front side of the main body case, an empty space for pressing the lock / release member is secured outside the left and right side surfaces of the main body case. You don't have to
Eliminates the need for a large installation space.

As described above, the cost can be reduced and the operability of the movable cover can be improved without increasing the installation space.

Further, in the invention of claim 2 having the above-mentioned structure, in addition, the direction of the rotational moment generated around the rotation axis of the movable cover due to the pressing force applied to the pressed portion of the lock / release member from the front is movable. Therefore, the movable cover is urged in the opening direction by the pressing force. As a result, it is possible to further smoothly open the movable cover.

[0019]

Embodiments of the present invention will be described below with reference to the drawings. As shown in FIGS. 1 to 4, the image forming apparatus has a main body case 11 accommodating an image forming transfer portion 41 and the like and a movable cover 21, and the movable cover 21 can be locked / unlocked at a closed position. The lock / release member 31 of the locking / unlocking means 30 is attached to the end 22F of the movable cover 21 on the front side of the main body case.
The auxiliary cover (38) is not required, and the cost can be reduced and the operability of the movable cover 21 can be improved.

First, in the main body case 11, in addition to the image forming transfer section 41 [process unit 42 (photoconductor 43, charging device 44, developing device 45, cleaning device 46), transfer device 47], an exposure device 51. (Polarizing unit 52 having polyhedral mirror 53, first and second Fθ lenses 54, 5
5, reflection mirrors 56, 57, dustproof glass 58, etc., fixing device 61 (heating roller 62, pressure roller 63, upper and lower casings 65, 66, etc.), paper feed unit 71 (paper feed tray 72, paper feed roller) 73, a sheet pressing plate 74, etc.) and a sheet conveying path 85, etc.

An opening is formed in the upper portion of the main body case 11 for convenience of attaching and detaching the process unit, paper jam processing, and the like, and the opening can be opened and closed by a movable cover 21.

A rear end 22R of the movable cover 21 is rotatably attached to the main body case 11 via a paper feed roller shaft 73a. A plurality of guide ribs 24 for conveying and guiding the paper are integrally formed on the back surface of the movable cover 21 at predetermined intervals in the width direction of the cover 21 (direction orthogonal to the paper surface in FIG. 1).

As shown in FIG. 2, the locking / unlocking means 30, which is a characteristic part of the image forming apparatus, includes an engaging portion 35 provided on the main body case 11 side and an end portion 22F of the movable cover 21 on the front side of the main body case. And a lock / release member 31 provided on the
The movable cover 21 can be locked and unlocked at the closed position. In this embodiment, the lock / release members 31 are provided at both left and right ends of the movable cover 21, as shown in FIG.

The lock / release member 31 is of a push type and is engaged with the pressed portion 32 which is displaced rearward when pressed from the front and the main body case 11 when the movable cover 21 is positioned at the closed position. A locking portion (a book that is engaged with the portion 35 to lock the movable cover 21 and displaces when the pressed portion 32 is pressed to release the engagement state with the engaging portion 35). In the embodiment, it is composed of a hook portion 33).

In particular, in the present embodiment, the lock / release member 31 has the rotation axis of the movable cover 21 (the axis of the paper feed roller shaft 73a) due to the pressing force F applied to the pressed portion 32, as shown in FIG. The direction of the rotational moment M generated around is provided so as to be the same as the opening direction (direction of arrow Q) of the movable cover 21.

Specifically, the lock / release member 31
Is provided above the line d passing through the rotation axis of the movable cover 21 in parallel with the action line a of the pressing force F. As a result, the movable cover 21 is biased in the opening direction (Q direction) by the pressing force F applied to the pressed portion 32, so that the movable cover 21 can be opened more smoothly.

More specifically, the engagement portion 35 is locked to the upper casing 65 of the fixing device 61 as shown in FIG.
The hook portion 33 of the release member 31 is formed by utilizing the front side edge portion of the hole portion 65h provided so as to be loosely fitted.

Further, the lock / release member 31 is made of synthetic resin, and as shown in FIG.
In addition to the hook portion 33, a guide protrusion 36 and a return spring portion 37, which will be described later, are integrally formed. The guide protrusions 36 are provided at both ends of the lock / release member 31, and have guide holes (24h, 24h) formed in predetermined guide ribs (24, 24) on the back surface of the movable cover 21.
It is slidably fitted in h). As a result, the lock / release member 31 can be smoothly and reliably moved in the front-rear direction while being guided by the guide holes (24h, 24h).

An elongated hole 36h is formed in the lock / release member 31 inside the guide protrusion 36, and when the lock / release member 31 is attached to the movable cover 21, the guide protrusion 36 is inward. It is configured so that it can be elastically deformed to and further inserted into the guide hole 24h of the guide rib 24.

The return spring portion 37 is, as shown in FIG. 2, a stopper 2 provided on the back surface of the movable cover 21.
The lock / release member 31 in cooperation with the hook 3
3 is formed so as to be capable of being biased toward a position where it engages with the engagement portion 35.

Next, the operation of this embodiment will be described. First, a printing operation using this image forming apparatus will be described. The sheets set in the sheet feeding tray 72 are separated one by one by the sheet feeding roller 73 and the sheet pressing plate 74, and are sent to the image forming transfer section 41 while being guided by the guide ribs 24 on the sheet conveying path 85. In the image forming transfer section 41, an electrostatic latent image is formed on the surface of the photoconductor 43 by the laser light emitted from the exposure device 51 based on the print data. This electrostatic latent image is developed by the toner supplied from the developing device 45 to form a toner image, and the transfer device 4
In FIG. 7, it is transferred onto the paper sent from the paper feed tray 72.

The sheet on which the toner image is transferred is further sent to the fixing device 61 and conveyed while being pinched by the heating roller 62 and the pressure roller 63. As a result, the toner image is fused and fixed on the paper. The sheet thus printed is discharged to the outside by the discharge roller 89.

By the way, when a paper jam occurs during the above-described printing operation, the movable cover 21 is fully opened to perform the jam processing.

To fully open the movable cover 21, a lock
The pressed portion 32 of the release member 31 is pushed from the front to release the engagement between the hook portion 33 and the engaging portion 35, and the movable cover 21 is maintained as it is, as shown by the chain double-dashed line in FIG.
A certain amount of angle (1 from the horizontal direction) in the opening direction (Q direction)
Rotate (00 °) only. At this time, since the direction of the rotation moment M generated around the rotation axis of the movable cover 21 due to the pressing force F applied to the pressed portion 32 is the same as the opening direction (Q direction) of the movable cover 21, the pressing force is increased. The movable cover 21 is biased in the opening direction by F,
The movable cover 21 can be opened more smoothly.

Thus, the jammed paper is taken out when the movable cover 21 is fully opened. When the movable cover 21 is rotated to the closed position after the jammed paper is taken out, the hook portion 33 of the lock / release member 31 is automatically engaged with the engaging portion 35 to lock the cover 21. Even when the process unit 42 is replaced, the movable cover 21 is opened and closed by the same procedure as described above.

Therefore, according to this embodiment, the locking / releasing means 30 is provided with the engaging portion 35 provided on the body case 10.
The movable cover 21 includes a lock / release member 31 provided at an end 22F on the front side of the main body case.
The release member 31 is engaged with the pressed portion 32 that is displaced rearward when pressed from the front and the engaging portion 35 when the movable cover 21 is positioned at the closed position to lock the movable cover 21. In addition, since the pressed portion 32 is displaced when pressed, the hook portion 33 is formed so as to be able to release the engaged state with the engaging portion 35.
As in (A) and (B)], it is not necessary to provide the auxiliary spring (39) and its mounting parts, and the cost can be reduced. Further, since the lock / release member 31 is provided at the end 22F of the movable cover 21 on the front side of the main body case, the lock / release member 31 is locked to the outside of the side surface 13 of the main body case 11 or the like.
Since it is not necessary to secure an empty space for pressing the release member 31, it is possible to save the installation space.

Further, the direction of the rotation moment M generated around the rotation axis of the movable cover 21 (the axis of the paper feed roller shaft 73a) is movable by the pressing force F applied to the pressed portion 32 of the lock / release member 31. Since the cover 21 is provided so as to be the same as the opening direction (Q direction), the movable cover 21 can be biased in the opening direction (Q direction) by the pressing force F. Therefore, the movable cover 21
Can be opened smoothly.

Further, the engaging portion 35 of the locking / releasing means 30.
Is formed by utilizing the upper casing 65 of the fixing device 61, the number of parts can be further reduced, and the cost can be further reduced.

Further, since the lock / release member 31 is attached by using the guide rib 24 formed on the back surface of the movable cover 21, the number of parts can be further reduced and the cost can be further reduced.

Further, the lock / release member 31 includes the guide projection 3 as well as the pressed portion 32 and the hook 33.
6 and the return spring portion 37 are also integrally provided, the number of parts and the number of assembling steps can be further reduced, and the cost can be further reduced.

Although the lock / release members 31 are provided at the left and right ends of the movable cover 21 in the above embodiment, the number of the lock / release members 31 is not limited to this. For example, the movable cover 21
One may be provided at the center of the front end 22F of the main body case.

[0042]

According to the invention of claim 1, the locking / releasing means is composed of an engaging portion provided on the main body case and a lock / release member provided on an end portion of the movable cover on the front side of the main body case. Then, the lock / release member is engaged with the pressed portion that is displaced rearward when pressed from the front and the engaging portion of the main body case when the movable cover is positioned at the closed position, thereby moving the movable cover. Since it is configured of a locking portion that is locked and that is displaced when the pressed portion is pressed to be able to release the engaged state with the engaging portion, the number of parts can be reduced and the cost can be reduced. Can be planned. Further, the operation of opening the movable cover can be performed quickly and easily. Further, it is not necessary to provide an empty space for pressing the lock / release member outside the side surface of the main body case, and it is not necessary to take a large installation space.

According to the second aspect of the invention, in addition, the direction of the rotational moment generated around the rotation axis of the movable cover by the pressing force applied to the pressed portion of the lock / release member is the opening direction of the movable cover. Since it is provided so as to be the same as, the cost can be reduced without increasing the installation space, and the operability of the movable cover can be further improved.

[Brief description of drawings]

FIG. 1 is a side sectional view for explaining an embodiment of the present invention.

FIG. 2 is a side sectional view for explaining the locking / releasing means.

FIG. 3 is likewise a perspective view for explaining a lock / release member.

FIG. 4 is likewise an external perspective view.

FIG. 5 is a diagram for explaining a conventional configuration of a locking / unlocking unit of the image forming apparatus.

FIG. 6 is a diagram for explaining another conventional configuration of the locking / unlocking means of the image forming apparatus.

[Explanation of symbols]

 11 Main Body Case 21 Movable Cover 22R Rear End 22F Main Body Case Front Side End 30 Locking / Release Means 31 Lock / Release Member 32 Pressed Part 33 Hook Part (Locking Part) 35 Engagement Part 36 Guide Protrusion 37 Return Spring part

Claims (2)

[Claims] 1. A main body case having an opening, a movable cover whose rear end is rotatably supported by the main body case and capable of opening and closing the opening of the main body case, and the movable cover which can be locked in a closed position. In an image forming apparatus having locking / releasing means capable of unlocking, the locking / releasing means is provided at an engaging portion provided on the main body case and an end portion of the movable cover on the front side of the main body case. A lock / release member, and the lock / release member is displaced to the rear when the lock / release member is pressed from the front; and the engaging portion of the main body case when the movable cover is positioned at the closed position. And a locking portion that is engaged with the movable cover to lock the movable cover and that is displaced when the pressed portion is pressed so that the engagement state with the engaging portion can be released. A characteristic image forming apparatus. 2. The lock / release member is provided so that the direction of the rotational moment generated around the rotation axis of the movable cover by the pressing force applied to the pressed portion is the same as the opening direction of the movable cover. The image forming apparatus according to claim 1, wherein: