JP2000135835A - Imaging apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent single closing by an arrangement wherein one of a pair of hooks for holding an open/close part in closed state has a U-shaped hooking part where the bottom face is inclining upward toward an opening and the other hook has a U-shaped hooking part inclining downward. SOLUTION: Hooks 50, 52 have upper ends 50a, 52a fixed rotatably to a part of upper body section 100 on the side of an open/close part and U-shaped hooking parts 50b, 52b are formed at the lower end of the hooks 50, 52. Bottom face of the hooking part 50b is bent along an arc 50d of radius 50R being described when the hook 50 turns and it is inclining downward toward an opening. On the other hand, bottom face of the hooking part 52b is bent along an arc 52d of radius 52R being described when the hook 52 turns and it is inclining upward toward an opening. Since these bottom faces touch hoof rolls 94 smoothly, the upper body section 100 can be opened/closed smoothly.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to an image forming apparatus such as a copying machine, a printer, and a plotter.

[0002]

2. Description of the Related Art As an output device of a computer or a work station, an ink jet type image forming apparatus for forming an image on a recording medium by discharging ink, or an electrophotographic type forming apparatus for forming an image on a recording medium using a developer or the like. Image forming apparatuses are known. These image forming apparatuses include an image forming unit on which an image is formed. Further, the image forming apparatus is generally provided with a paper feed unit for feeding a recording medium to the image forming unit, and a discharge unit formed on the opposite side of the image forming unit from the paper feed unit, A recording medium transport path for transporting the recording medium in a direction from the paper supply unit to the discharge unit is formed.

In the image forming apparatus, a rotating shaft is formed at one end (rear part of the main body) in a direction perpendicular to the recording medium conveying path, and an opening / closing part (front part of the main body) opposite to the one end is formed. There is a type (so-called crocodile type) that can be opened and closed to divide the apparatus main body into an upper body and a lower body. This alligator type image forming apparatus is configured such that when the opening / closing portion is opened, the recording medium transport path is largely exposed,
Paper jam (jam) can be easily handled by the user.

The above-mentioned alligator-type image forming apparatus of the electrophotographic type generally has an optical system and a photosensitive drum built in an upper part of a main body, and a cassette tray and a fixing device are built in a lower part of the main body. I have. The lower part of the main body is fixed, and the part of the upper part of the main body that is open,
The air and the like are configured to be pushed up by a sealed damper.

[0005] As the dampers, two dampers which are arranged at a predetermined distance from each other are usually used, and their upper ends are fixed to the front part of the upper part of the main body. The lower part is fixed to the front part of the main body. The repulsive force of these two dampers pushes up the main body front side portion of the main body upper part around the rotation axis of the main body rear part, and is divided into the main body upper part and the lower body part.

In the crocodile-type image forming apparatus described above, the opening and closing portion of the front portion of the main body is closed except for the jam processing. In order to close the opening / closing portion in this way, two hooks that suppress the repulsive force of the two dampers described above may be used. Each of the two hooks is arranged near the two dampers, and the upper end of the hook is fixed to the upper part of the main body. On the other hand, the lower end of the hook is shaped to be hooked on a hook hole formed by a hole of a sheet metal provided at a lower portion of the main body. When the user pushes down the upper part of the main body which is pushed up by the damper, the lower end of the hook is hooked on the hook hole, and the opening / closing part of the front part of the main body is closed, and the apparatus enters a standby state in which an image can be formed.

[0007]

As described above, when the two hooks for suppressing the repulsive force of the two dampers are pressed down on the upper part of the main body which is pushed up by the dampers, the lower ends of the hooks are caught in the hook holes. It has become.
However, when, for example, the end of the upper portion of the main body is pushed down, only the lower end of one of the two hooks may be caught in the hook hole. Such a state is called one-sided closing, and the positional accuracy of the optical system deteriorates, and the upper portion of the main body may be suddenly opened during image formation. Accordingly, an accurate image cannot be formed in the case of one-sided closing.

The present invention has been made in view of the above circumstances, and has as its object to provide an image forming apparatus in which the above-mentioned half closing is prevented.

[0009]

In order to achieve the above object, an image forming apparatus according to the present invention is characterized in that an opening / closing portion on the opposite side to a predetermined rotation axis is opened to open the upper part of the main body. And (1) an upper end portion is rotatably fixed to a portion of the upper portion of the main body on the opening / closing portion side, and has a concave shape at each lower end portion. A pair of hooks formed with a hook portion and holding the opening / closing portion in a closed state, and (2) a roller fixed to the lower portion of the main body, where the hook portion of each of the pair of hooks is hooked, (3) The hook portion of one of the pair of hooks has a U-shape whose bottom is inclined toward the opening, and (4) the other hook different from the one hook. The bottom of the hook is facing the opening It is characterized in that those U-shaped inclined to so that.

Here, (5) the bottom surface of the hook portion of the pair of hooks and / or the bottom surface of the hook portion of the other hook are:
These hooks may be curved along an arc drawn when the hook rotates.

(6) The pair of hooks may be capable of changing the distance between each other.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an embodiment of an image forming apparatus according to the present invention will be described with reference to the drawings.

FIG. 1 is a perspective view showing the appearance of a copying machine which is an embodiment of the image forming apparatus of the present invention.

On the top surface of a copying machine (an example of an image forming apparatus according to the present invention) 10, an openable and closable original pressing plate 12 is arranged. On the front side of the top surface, an operation panel display 14 for inputting the number of copies and the like is arranged.
The copying machine 10 is provided with a universal cassette 16 for accommodating a plurality of cut sheets so that the universal cassette 16 can be taken in and out from the front side of the copying machine 10. The right side wall of the copying machine 10 is provided with a rectangular manual tray 18 (see FIG. 2) capable of feeding small-size recording paper such as postcards.
As shown in FIG. 2, the manual feed tray 18 is
It rotates in the direction of arrow C around the center 8a, and opens to the position where the recording medium can be placed (the position indicated by the two-dot chain line). The left side wall of the copying machine 10 is provided with a paper discharge tray 20 on which recording paper on which an image is formed is stacked.

At the front of the copying machine 10, a rectangular front door 22 is provided.
However, it is fixed so that it may open to the near side with the lower side portion 22a as the center of rotation. By opening the front door 22, the inside of the copier 10 can be observed. With the front door 22 kept open, a pair of dampers 60, 62 (see FIG. 3) is removed by removing a pair of hooks 50, 52 (see FIGS. 3 and 4) disposed near the front door 22. 4 (see FIG. 4), the front side of the upper part of the main body of the copying machine 10 (the part where the optical system 28 and the photosensitive drum 32 shown in FIG. 2 are incorporated) is pushed up. As a result, the copying machine 10 is divided into an upper body and a lower body (a part in which the universal cassette 16 and the like are incorporated).

Referring to FIG. 2, a procedure for forming an image by the copying machine 10 of FIG. 1 will be described.

FIG. 2 is a schematic diagram showing an outline of the internal structure of the copying machine 10. As shown in FIG. 2, the same components as those of FIG. 1 are denoted by the same reference numerals.

An original table glass 26 on which an original 24 is placed is disposed below the original cover 12. The original 24 is placed on the original platen glass 26 so that the image surface faces downward, and the original 24 is pressed and fixed by the original cover 12. The image recorded on the document 24 is read by a known optical system 28 having a light source lamp (not shown) or the like, and light (broken line A) carrying information of the image recorded on the document is obtained.
This light is applied to the photosensitive drum 32 uniformly charged by the charging unit 30 to form an electrostatic latent image. This electrostatic latent image is developed with the developer (toner) supplied from the developing unit 34 to form a developed image. On the other hand, a recording medium such as recording paper sent from the universal cassette 16 is fed in the direction of arrow B, and the developed image is transferred to the recording medium in the transfer unit 36.

The recording medium onto which the developed image has been transferred
By 8, it is conveyed to the fixing unit 40. A heat roller 42 and a press roller 44 are arranged in the fixing unit 40,
The recording medium is conveyed while being sandwiched between these two rollers 42 and 44, and the developed image is fixed on the recording medium. The recording medium on which the developed image has been fixed in this manner is discharged and stacked on the discharge tray 20. After the transfer, the photosensitive drum 3
2 is scraped off by the cleaning device 46. Also, the recording medium can be fed from the manual feed tray 18, and the procedure for forming an image on the recording medium fed from the manual feed tray 18 is the same as described above.

Referring to FIGS. 3 and 4, the upper part of the main body of the copying machine is pushed up, and the copying machine is moved to the upper part and the lower part of the main body.
The state of division will be described.

FIG. 3 is a perspective view showing the copying machine with the front door opened, and FIG. 4 is a perspective view showing the copying machine with the front door opened and the upper part of the body of the copying machine pushed up. In these figures, the same components as those shown in FIGS. 1 and 2 are denoted by the same reference numerals.

In the copying machine 10, the universal cassette 1
The recording medium sent from 6 is conveyed to the inside of the copying machine 10 from the paper supply unit 70 on the right side of the paper surface of FIGS.
The recording medium on which the image is formed by the copying machine 10 is discharged to the discharge tray 20 from the discharge unit 72 on the left side of the paper surface of FIGS. As described above, the copying machine 10 is formed with the recording medium transport path in which the recording medium is transported in the direction from the paper feeding unit 70 to the paper discharging unit 72.

The copying machine 10 is divided into an upper body 100 (a part in which the optical system 28 and the photosensitive drum 32 shown in FIG. 2 are incorporated) and a lower body 200 (a part in which the universal cassette 16 and the like are incorporated). When the pair of dampers 60 and 62 push up the front part of the main body upper part 100, the opening / closing part 74 of the front part of the copying machine 10 is opened. The damper 60 is located near the paper feeding unit 70 and
0 is located in the front part. Also, the damper 62
It is located near the paper discharge unit 72 and at the front side of the copying machine 10.

The opening / closing section 74 is opened and closed about a rotation shaft 76 formed on a main body rear plate (not shown) located at a rear portion of the copying machine 10. The opening / closing part 74 and the rotation shaft 76 are formed at one end in the cross direction intersecting the recording medium transport path and the other end opposite to the one end.

The hook 50 is arranged on the left side of the paper of the damper 60, and the hook 52 is arranged on the right side of the paper of the damper 62. These hooks 50 and 52 are connected to a roller shaft 90 attached to the lower part 200 of the main body, as will be described later.
(See FIG. 5 and FIG. 6).
The opening / closing section 74 is kept closed by overcoming the repulsive force of 0,62.

Referring to FIG. 5 to FIG.
0, 52, the roller shaft 90, and the hook roller 94 will be described. The roller according to the present invention includes a roller shaft 90 and a hook roller 94.

First, a state in which the hook is hooked on the hook roller will be described with reference to FIG. FIG. 5 is a schematic diagram of the copying machine 10 exaggerating the hooks. In this figure,
The same components as those in FIGS. 1 to 4 are denoted by the same reference numerals.

The hooks 50 and 52 are, as shown in FIG.
It is arranged in parallel with the dampers 60 and 62. Hook 5
The upper ends 50a and 52a of the upper and lower parts 0 and 52 are rotatably fixed to a part of the upper part 100 of the main body on the side of the opening / closing part 74 (see FIG. 4). At the lower ends of the hooks 50 and 52, hooks 50b and 52b having a "U" shape are formed. Each of the hooks 50b, 52b of the hooks 50, 52 is hooked and locked by the roller shaft 90, so that the damper 6
The opening / closing section 74 can be kept closed by overcoming the repulsive force of 0,62. By rotating the release lever 54 in the direction of arrow D, the two hooks 50 and 52 are linked to rotate
The lock is released by rotating in the direction of arrow D about c and 52c, and the upper part 100 of the main body is pushed up by the dampers 60 and 62 (see FIGS. 3 and 4).

Referring to FIGS. 6 and 7, hooks 50, 52 are provided.
The shape of the hook portions 50b and 52b will be described.

FIG. 6 is an enlarged schematic view showing a hook portion of the hook 50, and FIG. 7 is an enlarged schematic diagram showing the hook portion of the hook 52.

As shown in FIG. 6, the bottom surface of the hook 50b has an arc 5 of a radius 50R drawn when the hook 50 rotates.
It is curved along 0d, and the bottom surface 50e is inclined so as to descend toward the opening 50f. On the other hand, the hook 52b
7, is curved along an arc 52d having a radius 52R drawn when the hook 52 rotates, as shown in FIG.
The bottom surface 52e is inclined so as to rise toward the opening 52f. Therefore, the bottom surfaces 50e, 52e and the hook rollers 94 are in smooth contact with each other, so that the upper body 100 can be smoothly opened and closed.

The configuration of the rollers will be described with reference to FIG.

FIG. 8 is a perspective view showing a state where the hook rollers are attached to the support base. The roller shaft 90 is fixed to a support base 96 fixed to the bottom plate of the lower part 200 of the main body. The roller shaft 90 has a columnar shape, and both ends of the support shaft 9 are supported.
6 and is rotatably fixed by an E-shaped retaining ring 92. The outer peripheral surface of the roller shaft 90 is covered with a cylindrical hook roller 94 rotatable in the circumferential direction. However, the outer diameter of the roller shaft 90 and the inner diameter of the hook roller 94 are substantially the same, and the hook roller 94 is almost fitted to the roller shaft 90, so that there is almost no play.

Referring to FIG. 9, a case where only the upper part of the upper part 100 of the main body 100 above the hook 50 is depressed will be described.

FIG. 9 is a schematic diagram showing one-sided closing.

When only the upper part of the hook 50 in the upper part 100 of the main body is pushed down, the hook 50b of the hook 50
The hook roller 94 approaches the opening 50f (see FIG. 6).
However, the hook 50b of the hook 50 has a U-shape in which the bottom surface 50e is inclined toward the opening 50f as described with reference to FIG.
Is easily detached from the hooking portion 50b (easily escaped). In addition, the hook 52b of the hook 52 is not sufficiently pushed down, and the bottom surface 52e of the hook 52b is inclined so as to rise toward the opening 52f, so that the hook roller 52 is close to the opening 52f of the hook 52b. Even if you have 94,
The hook roller 94 passes through the opening 52f and engages with the hook 52b.
Hook 52 so that it goes all the way in
Is difficult to rotate. As a result, the hook roller 94 is not hooked on both the hook portions 50b and 52b of the hooks 50 and 52,
The main body upper portion 100 remains open without being closed. Therefore, the hook roller 94 is not hooked on only one hooking portion of the pair of hooks 50, 52, and the one-side closing can be prevented.

In the above example, the description has been made assuming that only the upper part of the hook 50 in the upper part 100 of the main body is depressed.
The case where only the upper part of 2 is pushed down will be described.

When only the upper part of the hook 52 in the upper part of the main body is pushed down, the hook roller 94 approaches the opening 52f of the hook 52b of the hook 52. However, since the hook 52b of the hook 52 has a U-shape in which the bottom surface 52e is inclined toward the opening 52f,
The hook 52 is unlikely to rotate so that the hook roller 94 passes through the opening 52f and enters the hook 52b. In addition, the hook 50b of the hook 50 is not sufficiently pressed down, and the bottom surface 50e of the hook 50b is inclined downward toward the opening 50f.
b, even if the hook roller 94 is located near the opening 50f, the hook roller 94 is
The hook 50 is hard to rotate so as to enter the depth of 0b. As a result, the hook 5
The hook roller 94 is not hooked on the hooking portion 50b of 0,
The main body upper portion 100 remains open without being closed. Therefore, the hook roller 94 is not hooked on only one hooking portion of the pair of hooks 50, 52, and the one-side closing can be prevented.

As described above, the pair of hooks 50, 52
Of the pair of hooks 50 and 52 even if only one of the
The hook rollers 94 are not hooked on 0b and 52b, so that the one-side closing can be prevented. The connection of the hooks 50 and 52 will be described with reference to FIG.

FIG. 10 is a schematic diagram showing hooks 50 and 52 and connecting rods for connecting them, and the same components as those in FIGS. 5 to 9 are denoted by the same reference numerals. The pair of hooks 50 and 52 are connected to each other by connecting rods 82 and 84. The connecting rod 84 has two long holes 84a,
The connecting rod 82 has holes (not shown) corresponding to the long holes 84a and 84b. The holes formed in the connecting rod 82 and the long holes 84a, 84
b through the bolts or screws, connecting rod 8
2, 84 are fixed to each other.

Due to the variation in the accuracy of each part of the copying machine 10 (see FIG. 1), the hooks 50b,
The positional relationship between 52b and hook roller 94 may be shifted. In this case, hook portions 50b, 52 of hooks 50, 52
In some cases, the hook roller 94 may be caught on only one of the members b, and the hook roller 94 may be partially closed. In such a case, the connecting rod 84 is moved to change the positions of the bolts and screws that penetrate the two long holes 84a and 84b and the holes of the connecting rod 82.
Thereby, hook portions 50b, 52b of hooks 50, 52
The distance between the hooks 50 and 52 can be changed so that the hook rollers 94 are securely hooked on both sides, and the one-sided closing can be prevented.

[0042]

As described above, in the image forming apparatus of the present invention, when only the upper portion of one of the upper hooks of the main body is pushed down, the roller approaches the opening of the hook portion of the one hook. However, the hook of this one hook is
Since the bottom has a U-shape inclined so as to rise toward the opening, one of the hooks is difficult to rotate so that the roller passes through the opening and enters the interior of the hook. Moreover, the hook of the other hook is not sufficiently pushed down, and the bottom surface of the hook is inclined downward toward the opening, so that there is a roller near the opening of the hook. However, the other hook is difficult to rotate so that the roller enters the hook portion through the opening. As a result, the rollers do not catch on the hooks of one hook and the hooks of the other hook, and the upper part of the main body remains open without being closed.
Therefore, the roller is not hooked on only one hooking portion of the pair of hooks, and the one-sided closing can be prevented.

Conversely, when only the upper part of the other hook in the upper part of the main body is pushed down, the roller approaches the opening of the hook portion of the other hook. However, since the hook of the other hook has a U-shape whose bottom is inclined toward the opening, the roller is likely to come off from the hook. In addition, the hook of one hook is not sufficiently pushed down, and the bottom of this hook is inclined so as to rise toward the opening, so if there is a roller near the opening of this hook, However, it is difficult for one hook to rotate so that this roller enters the hook portion through the opening. As a result, the rollers do not catch on the hooks of one hook and the hooks of the other hook, and the upper part of the main body remains open without being closed. Therefore, the roller is not hooked on only one hooking portion of the pair of hooks, and the one-sided closing can be prevented.

That is, even if only one of the pair of hooks is pushed down so as to be partially closed, the roller does not catch on the hook portions of both the pair of hooks, so that the one-sided closure can be prevented.

Here, if the bottom surface of the hook portion of the pair of hooks and / or the bottom surface of the hook portion of the other hook are curved along the arc drawn when these hooks rotate, the hook portion The bottom surface is curved along the arc drawn when the hook rotates, so that the bottom surface and the roller are in smooth contact, and the upper part of the main body can be smoothly opened and closed.

When the distance between the pair of hooks can be changed, the positional relationship between the hook hooking portion and the hook roller is shifted due to variations in the accuracy of each component of the image forming apparatus. Even if it is not the distance, the mutual distance can be changed, so that the positional relationship between the hook portion and the hook roller can be appropriately changed, and the one-sided closing can be prevented.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an external appearance of a copying machine which is an embodiment of an image forming apparatus of the present invention.

FIG. 2 is a schematic diagram showing an outline of an internal structure of the copying machine shown in FIG. 1;

FIG. 3 is a perspective view showing the copying machine with a front door opened.

FIG. 4 is a perspective view showing the copying machine in which a front door is opened and an upper part of the body of the copying machine is pushed up;

FIG. 5 is a schematic view of a copying machine in which hooks are exaggerated.

FIG. 6 is an enlarged schematic view showing a hook portion of a hook 50;

FIG. 7 is an enlarged schematic view showing a hook portion of a hook 52;

FIG. 8 is a perspective view showing a state in which hook rollers are attached to a support base.

FIG. 9 is a schematic diagram showing one-sided closing.

FIG. 10 is a schematic diagram showing a pair of hooks and a connecting rod connecting these hooks.

[Explanation of symbols]

 10 Copier 50, 52 Hook 50b, 52b Hook Hook 50e, 52e Hook Bottom 50f, 52f Hook Open 50d, 52d Arc 90 Roller Shaft 94 Hook Roller

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Yoshiyuki Koshimizu 3-30-2 Shimomaruko, Ota-ku, Tokyo F-term in Canon Inc. (reference) 2C061 AP04 AQ06 AS02 BB15 BB17 CD07 CD11 CD13 CD14 2H071 AA14 AA18

Claims (3)

[Claims] 1. An image forming apparatus which is divided into two parts, a main body upper part and a main body lower part, by opening an opening / closing part on a side opposite to the predetermined rotation axis with respect to the predetermined rotation axis. A pair of hooks, which are rotatably fixed to a portion on the opening and closing portion side of the upper portion of the main body and have a concave hook portion formed at each lower end, hold the opening and closing portion in a closed state, A roller fixed to the lower part of the main body, on which the hooks of each of the pair of hooks are hooked, wherein a hook of one of the pair of hooks is inclined such that the bottom surface rises toward the opening. The hook portion of the other hook different from the one hook,
An image forming apparatus having a U-shape whose bottom surface is inclined toward an opening. 2. A bottom surface of a hook portion of the pair of hooks and / or
2. The image forming apparatus according to claim 1, wherein a bottom surface of the hook portion of the other hook is curved along an arc drawn when the hook rotates. 3. 3. The image forming apparatus according to claim 1, wherein a distance between the pair of hooks can be changed.