JPH11341204A - Opening/closing device of cover - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an opening/closing device of a cover which is simple in structure and can attach a cam material to a body casing so that it does not rotate. SOLUTION: A cam material has a cam surface which is in parallel to a rotating shaft of a first cover 82 formed on itself and has a plane part which press-contacts a first support frame (a part on a body casing 81 side) by receiving a pressurized force from a press contact engagement part of a movable rod material. Even if the pressed force from a coil spring is received by way of the press contact engagement part, the plane part of the cam material press- contacts the first support frame and the cam material does not idle. A control part controls that the plane part rotates in a direction of separating from the first support frame.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention mainly relates to a cover opening / closing device used in an image forming apparatus such as a copying machine, a printer, a facsimile machine and the like.

[0002]

2. Description of the Related Art Conventionally, for example, copiers, printers,
In an image forming apparatus such as a facsimile machine, for exchanging an ink cartridge or processing a paper jam, etc.
A cover is provided on the main body casing so as to be openable and closable. Simply by pivoting such a cover rotatably with respect to the main body casing, even if the cover is opened, it will fall and be closed by its own weight if you let go of the hand. For example, it is necessary to hold it with one hand, and since the operation is troublesome, a cam member is provided on the rotating shaft on the cover side to improve operability, and a cam follower contacting the cam member is provided on the body casing side. The cam follower is urged by an urging means so that the cam surface of the cam member acts on the cam follower to hold the cover at its rotational displacement position in the process of changing the cover from the closed state to the open state. What has become known is known.

[0003]

However, in such a device, since the cam surface of the cam member receives a load from the cam follower, a so-called D-cut (cutting) is performed so that the cam member does not rotate with respect to the rotating shaft. ) Or fixing with screws, the structure is complicated, the assembly is troublesome, and the cost is disadvantageous.

Therefore, for example, Japanese Patent Application Laid-Open No. Sho 60-146232
As described in Japanese Patent Application Laid-Open Publication No. H10-209, a cam member is provided on the main body casing side, but it is necessary to fix the cam member to the main body casing so as not to rotate,
There is still a problem that the structure becomes complicated.

Further, Japanese Patent Application Laid-Open No. Sho 60-146232 describes the above.
In the conventional device described in Japanese Patent Application Laid-Open No. H10-260, the cam surface and the cam follower are not brought into contact with each other at a predetermined pressure by the urging means at any opening and closing angle of the cover.
Since the cover cannot be held at a fixed opening / closing angle, when assembling the cover opening / closing device including the cam member, the cam follower, and the urging means, the cam member and the cam follower must be assembled in a state where the cam member and the cam follower abut at a predetermined pressure. However, the assembling man-hours are required, which causes an increase in equipment cost.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a cover opening / closing device having a simple structure and capable of attaching a cam member to a main body casing so as not to rotate.

[0007]

According to a first aspect of the present invention, there is provided a cover opening / closing apparatus in which a cover is supported on a main body via a rotary shaft so as to be openable and closable. A movable member provided on the cover side and having an abutting portion that abuts on the cam portion of the cam member; and a biasing member that biases the movable member in a direction in which the abutting portion abuts on the cam portion of the cam member. A biasing member, and the cam member has a flat portion formed in parallel with the rotation axis and abutting on a portion on the main body side by receiving a pressing force from the movable member.

According to the first aspect of the present invention, the cam member is formed in parallel with the rotation axis of the cover, and has the flat portion which comes into contact with the main body side portion under the pressing force from the movable member. Even when the pressing force from the movable member is received, the flat portion of the cam member abuts on the body-side portion, and the cam member does not idle.

According to a second aspect of the present invention, there is provided the cover opening and closing device according to the first aspect, further comprising first and second rotatably provided via the rotary shaft respectively provided on the main body and the cover.
Wherein the first support frame is provided with a cam member on the rotating shaft, and the second support frame is provided with a movable member, and the cam member is further provided on the first support frame. The engaging portion has a restricting portion that restricts the flat portion from separating from the first support frame.

According to the second aspect of the present invention, when the cam member is engaged with the first support frame, the flat portion becomes the first portion.
Has a restricting portion that restricts the flat portion from moving away from the first support frame. Therefore, the cam member does not rotate in any direction due to the engagement relationship between the flat portion and the regulating portion.

According to a third aspect of the present invention, in the cover opening / closing device of the first or second aspect, the urging member is provided within a support portion for supporting the movable member, and is wider than a width inside the support portion. A short natural-length coil spring, wherein the cam member has a non-load surface on the cam surface such that the biasing member has a natural length when the cover is at a predetermined angle with respect to the main body. is there.

According to the third aspect of the present invention, the biasing member is a coil spring having a natural length shorter than a width inside the support portion, provided in the support portion for supporting the movable member,
And since the cam member has a no-load surface on the cam surface such that the urging member has a natural length when the cover is at a predetermined angle with respect to the main body, the contact portion of the movable member is In the state opposed to the no-load surface, the coil spring can be easily mounted on the support portion without being pre-compressed while maintaining its natural length. Further, when the cover is closed, a spring force acts in a direction to open the cover in a state where the coil spring is compressed, so that the cover can be easily opened using the spring force of the coil spring. it can.

According to a fourth aspect of the present invention, in the cover opening / closing device of the third aspect, the movable member is connected to a shaft around which the coil spring is wound, and an end of the coil spring is connected to an end of the shaft. And an engaging portion having a substantially elliptical cross section that engages with the supporting portion, and a through-hole through which only the engaging portion penetrates is formed in the support portion.

According to the fourth aspect of the present invention, the cover opening / closing device of the present invention can be assembled very easily in a state where the cover is at a predetermined angle with respect to the main body. That is, by inserting an urging member made of a coil spring having a natural length shorter than the width thereof inside the support portion, and further inserting the movable member into the support portion from the shaft portion side through the through hole, the coil The cover opening / closing device can be easily assembled without pre-compression of the spring. The assembled state is a state where the no-load surface of the cam surface and the contact portion of the movable member are opposed to each other, and corresponds to a case where the cover is at a predetermined angle with respect to the main body.

According to a fifth aspect of the present invention, in the cover opening / closing device according to any one of the first to fourth aspects, a stopper member for connecting the cover and the main body and having a temporary fixing hole is provided. And a projection which is provided in the stopper member and is engaged with the temporary fixing hole of the stopper member.

According to the fifth aspect of the present invention, the stopper member is positioned by engaging the temporary fixing hole of the stopper member with the projection on the cover side, and the mounting of the stopper member on the cover member is facilitated. You.

[0017]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is an explanatory view of a first cover opening / closing device in which the internal structure is omitted in a facsimile apparatus as an example of an image forming apparatus employing the cover opening / closing device according to the present invention, and FIG. FIG. 4 is an explanatory diagram illustrating a state where a first cover is opened in the device.

The main body casing 81 of the facsimile machine 1
Is made of a synthetic resin and has a substantially square housing as viewed from above with an open upper end. A first cover 82 that covers an upper end opening 81a of the main casing 81 is openably and closably attached to the main casing 81. First cover 82
Has a base 82a extending downward on both left and right sides,
The base 2a is supported by a rotating shaft 83 so as to be openable upward.

The opening and closing device for the first cover 82 is shown in FIG.
As shown in FIG. 2, a first support frame 86A is attached and fixed to a main body casing 81, and a cam member 84 is attached to the first support frame 86A by the rotating shaft 83, while a first cover 82 is provided. A second support frame 86B rotatably connected to the first support frame 86A via the rotation shaft 83 is attached and fixed to the first support frame 86A. The cam member 84 is attached to the second support frame 86B.
Contact portion 8 having an elliptical cross section that slides on the cam surface 84a
A movable rod member 85 having a tip 5a is slidably provided. Therefore, the first support frame 8
6A is connected to the second support frame 86B via the rotation shaft 83.
The cam member 84 is attached to the first support frame 86A by the rotation shaft 83.

The cam member 84 is formed in parallel with the axis of the rotating shaft 83 and receives a pressing force from the movable rod member 85, as shown in FIG. Flat part 8 in contact with the side part
4b. Further, the cam member 84 further has a restriction portion 84c that restricts the planar portion 84b from coming away from the first support frame 86A by engaging with the first support frame 86A.

The movable rod member 85 is supported by a support portion 86a formed on a second support frame 86B. The movable rod member 85 has a contact engagement portion 85a having an elliptical cross section and a circular cross section provided continuously therewith. And a shaft portion 85b.
A coil spring 87 is provided around 5b for urging the contact engagement portion 85a of the movable rod member 85 in the direction of contact with the cam surface 84a of the cam member 4 when the first cover 82 is closed. This coil spring 87
Second support frame 86 supporting movable rod member 85
B is housed in a support portion 86a formed around B and is wound around a shaft portion 85b. The natural length of the coil spring 87 is shorter than the width L (see FIG. 3) inside the support portion 86a.

The contact engagement portion 85a has a front end surface in contact with the cam surface 84a and a rear end surface in the coil spring 87.
To come into contact with the end face. A movable rod member 85 is provided on the support portion 86a of the second support frame 86B.
The through-holes 86c and 86d have a size corresponding to the cross-sectional shape of the contact engagement portion 85a and the shaft portion 85b, but are smaller than the diameter of the coil spring 87. Supported, movable rod member 8
The length of the coil spring 87 can be changed only by the forward / backward movement of No. 5. When the first cover 82 is closed, the movable rod member 85
Is retracted, the coil spring 87 is compressed to the maximum compression state by the contact engagement portion 85a, and a spring force acts in a direction in which the first cover 82 opens.

The first cover 82 and the main body casing 81 are connected by a band-shaped stopper member 91 to regulate the opening degree of the first cover 82 relative to the main body casing 81 within a certain range. I have. The lower end of the stopper member 91 is screwed to the main body casing 81 with a screw 92. The upper end of the stopper member 91 is provided with a temporary fixing hole 81a formed in the upper end thereof as shown in FIG. 8
In a temporarily fixed state engaged with the projection 86b of 6B, the second support frame 86B is screwed with a screw 93.

Therefore, when the locking of the first cover 82 (not shown) by the locking means to the main body casing 81 is released, the spring force of the coil spring 87 acts in the direction of moving the movable rod member 85 forward, and The degree of opening of the first cover 82 is gradually increased. That is, when the first cover 82 starts shifting from the closed state to the open state, the first cover 82 is moved by the spring force of the coil spring 87 from the engagement relationship between the cam surface 84a and the contact engagement portion 85a. To cancel the load received through the opening to facilitate the opening operation.

Then, when the first cover 82 is at the first set angle with respect to the main body casing 81, FIG.
As shown in (2), the stopper member 91 is in the extended state, and further opening is restricted. In this state, the coil spring 87 is in a slightly compressed state, and in order to close the first cover 82, the coil spring 87 must be further compressed, so that some load is applied to the first cover 82. If not, the first cover 82 will be kept open.

When the restriction by the stopper member 91 is released, the first cover 82 is further opened by the spring force of the coil spring 87, and when the coil spring 87 reaches the second set angle (predetermined angle), the coil spring 87 comes into contact with the no-load surface 84d having a natural length.

In the center of the first cover 82 near the front end, a second operation panel or the like is provided on the upper side.
Cover 94 is openably mounted.

As shown in FIGS. 5 and 6, the second cover 94 is provided with a rotating shaft 95 protruding in the left-right direction via an extension 95a on the left and right sides on the base end side. The rotating shaft portion 95 can be engaged with and disengaged from a substantially U-shaped groove portion 96a which is an engaging concave portion 96 formed on the left and right rear side portions of the first cover 82 and opens to an engaging pin 97 described later. Is engaged.

Near the left and right ends on the base end side of the second cover 94, semicircular guide holes 98a are formed.
A protruding plate 98 having a (long hole) is provided so as to protrude downward, and engaging pins 97 provided on both sides of the first cover 82 are removably engaged with the guide holes 98a. ing.

As described above, the engagement relationship between the rotation shaft 95 and the groove 96a and the engagement relationship between the guide hole 98a and the engagement pin 97 make them relatively slidable and rotatable. As a result, the second cover 94 is openably and closably supported by the first cover 82. That is, by opening and closing the second cover 94, the rotation shaft 95 and the engagement pin 97 on the first cover 82 side are opened.
Moves within the groove 96a and the guide hole 98a.

The engagement pin 97 is, as shown in FIG.
When the engagement pin 97 is engaged with the guide hole 98a,
A guide surface 97a for moving the protruding plate portion 98 toward the distal end of the engagement pin 97 is provided.
8 is pressed down, the lower edge thereof is guided by the guide surface 97a of the engaging pin 97, and is smoothly inserted into the guide hole 98a. Further, the guide surface 97a of the engagement pin 97 is formed only on a portion opposite to the side where the groove portion 96a is located, and is inadvertently guided on the guide surface 97a during the opening / closing operation of the second cover 94. Then, the insertion is not released.

The first and second cutouts 98b and 98 are formed at the side edge of the protruding plate 98 at the lower end and the middle.
c is formed so as to engage with the distal end engaging portion 99a of the leaf spring member 99 provided on the first cover 82 side in a detachable manner.

The leaf spring member 99 is made of a thin, thin plate-like spring steel, and the base end of the spring member 99 is attached and fixed to the first cover 82. Further, the distal end engaging portion 99a of the spring member 99 is formed to be bent in a substantially mountain shape, and
When the cover 92 is opened, the first notch 98b of the protruding plate 98 engages removably so as to rest on the upper surface of the tip engaging portion 99a, and the second cover 92 is kept open. Is done. The second notch 98c of the protruding plate portion 98 is formed in a substantially mountain shape corresponding to the tip engaging portion 99a.
When the cover 92 is completely closed, the cover 92 is fitted into the distal end engaging portion 99a of the leaf spring member 99, and the closed state is maintained.

FIG. 7 is a schematic diagram showing the internal structure of a facsimile apparatus having a cover opening / closing device according to the present invention.

As shown in FIG. 7, in a main body case 2 of the facsimile machine 1, a feeder unit 10 for feeding paper for image formation, a laser scanner unit 25 and a laser printer 20 having a photosensitive drum 21 are provided. When,
A document reading device 70, a drive mechanism (not shown) for driving a drive system including the photosensitive drum 21 and various rollers, and a control unit (not shown) for controlling the facsimile machine 1
Are provided.

In the feeder unit 10, a paper pressing plate 11 is disposed in a feeder case 2 a above a rear end of the main body case 2, and the front end of the paper pressing plate 11 is elastically moved upward by a compression spring 12. The paper feed roller 13 that is urged and feeds the paper 3 is rotatably pivotally supported. The paper feed roller 13 is driven to rotate at a predetermined paper feed timing by a drive mechanism (not shown).

Then, in the feeder section case 2a,
A paper feed cassette 14 capable of storing a plurality of sheets 3 of fixed cut paper is detachably mounted in an inclined state, and the paper 3 stored in the paper feed cassette 14 is supplied one by one by rotation of a paper feed roller 13. Paper. On the downstream side of the paper feed roller 13 in the transport direction (in FIG. 7, from rear to front),
A pair of registration rollers 15 for aligning the leading ends of the fed sheets 3 are rotatably supported respectively.

Next, the laser printer 20 is a developing unit having a cylindrical photosensitive drum 21, a laser scanner unit 25 for forming an electrostatic latent image on the photosensitive drum 21, a toner box 35, and a developing roller 43. 40
And a transfer roller 45 for transferring the toner image on the photosensitive drum 21 onto the paper 3, a fixing unit 50, and a drive mechanism (not shown) for driving the photosensitive drum 21, the developing roller 43, and the like.

The photosensitive drum 21 has a hollow shape in which a photoconductive layer having a predetermined thickness (for example, about 20 μm) in which a photoconductive resin is dispersed in polycarbonate is formed on an outer peripheral portion of an aluminum cylindrical sleeve. , And is rotatably supported by the main body case 2. In other words, the positively charged electrostatic latent image formed on the photosensitive drum 21 is developed with the positively charged toner 37 by the reversal development method.

The laser scanner unit 25 is disposed below the photosensitive drum 21 and is driven to rotate by a semiconductor laser emitter 26 that generates a laser beam R for forming an electrostatic latent image on the photosensitive drum 21. The semiconductor laser light emitter 26 includes a polygon mirror 27 (pentahedral mirror), a pair of lenses 28 and 29, a pair of reflection mirrors 30 and 31, and the like.
An electrostatic latent image can be formed on the photosensitive drum 21 by performing main scanning with the laser light R emitted from the photosensitive drum 21.

On the other hand, a scorotron-type charger 32 for generating a corona discharge from a charging wire made of tungsten or the like at a position advanced in the rotation direction from the position on the photosensitive drum 21 where the laser beam R is irradiated. The discharge lamp 33 is provided at a position further advanced in the rotation direction than the charger 32.

Next, the toner box 35 and the developing unit 40 disposed immediately behind the photosensitive drum 21 will be described.

The developing unit case 2b is provided with an agitator 36 which is driven to rotate, and an insulating toner 3 having an electric insulating property.
7 is detachably mounted, and a double cylindrical toner box 35 accommodating the toner box 7 is mounted on the front side of the toner box 35.
A toner storage chamber 41 for storing the toner 37 supplied by the rotation of the agitator 36 through a toner supply port formed in the toner box 35 is formed, and a supply roller 42 is rotatably pivoted in the toner storage chamber 41. The developing roller 43 is rotatably supported so as to partition the front side of the toner storage chamber 41 and to be in contact with the supply roller 42 and the photosensitive drum 21, respectively. Here, the toner 37 is made of synthetic resin having a particle diameter of 7 to 10 μm, and the supply roller 42 and the developing roller 43 are made of conductive rubber.

On the other hand, a thin plate-like elastic layer-thickness regulating blade 44 made of stainless steel or phosphor bronze is attached downward to the developing unit case 2b, and a bent portion formed at the lower end thereof is formed with a developing roller 43. The layer thickness of the toner 37 supplied from the supply roller 42 and adhered to the surface of the developing roller 43 in a layer form is regulated by the layer thickness regulating blade 44.

A cooling fan 5 is provided directly below the developing unit 40. By driving the cooling fan 5, the toner box 35 is particularly cooled to prevent the toner 37 from coagulating due to a rise in temperature. Thus, the image quality is prevented from deteriorating. Further, a toner temperature detection sensor 6 composed of a thermistor is provided immediately below the toner box 35 in close proximity to the toner box 35, and the toner temperature detection sensor 6 detects a temperature reflecting the temperature of the toner 37. Has become.

Then, the photosensitive drum 21 and the supply roller 4
2. Since the developing roller 43 and the like are each driven in a predetermined rotation direction by the driving mechanism, each toner particle of the toner 37 is
By rubbing between the supply roller 42 and the developing roller 43,
The toner 37 is charged to a positive polarity by the friction of the layer thickness regulating blade 44 against the developing roller 43, and the toner 37 charged to the positive polarity adheres to the electrostatic latent image formed on the photosensitive drum 21 by the laser beam R. And is developed by a reversal development method.

Next, a transfer roller 45 made of rubber having conductivity is provided so as to be in contact with the upper side of the photosensitive drum 21 and is rotatably supported by a pivot. The toner image on the photosensitive drum 21 is transferred by the transfer roller 45. , Is surely transferred to the paper 3.

The fixing unit 50 is provided downstream of the photosensitive drum 21 in the transport direction and includes a heating roller 52 having a fixing heater 51 such as a halogen lamp and a pressing roller 53. The heated toner image is heated simultaneously with the pressing, and is fixed on the sheet 3. Here, a heater temperature detection sensor 7 composed of a thermistor is provided close to the heating roller 52, and the surface temperature of the heating roller 52 is detected by the heater temperature detection sensor 7.

At the downstream side of the fixing unit 50 in the transport direction, a pair of transport rollers 55 for transporting the paper and a paper discharge tray 56 are provided, respectively. Here, the paper feed roller 13, the registration roller 15, the supply roller 42, the developing roller 43, the transfer roller 45, the pressing roller 53, and the transport roller 55 are not specifically illustrated, but are driven by a motor for LF through a gear mechanism. And each is driven to rotate.

Subsequently, a document separating device 6 for transporting the document 4
0 and the document reading device 70 will be described.

An operation panel 8 having a keyboard 8a provided with a power switch, a mode setting switch, a numeric keypad, and various function keys and a liquid crystal display 8b is provided on the front upper portion of the main body case 2. The document 4 on which the document insertion guide 61 is placed
And a document reading device 70 that reads an image (information such as characters and drawings) recorded on the document 4.

The original 4 placed on the original insertion guide 61 is read by an original reading device 70 by a pair of upper and lower original feed rollers 62, a paper guide 63 for guiding the original, and a pair of original discharge rollers 64. The document is conveyed to a position, and these constitute a transport unit for transporting the document along the transport path. The original feed roller 62 and the original discharge roller 6
Although not specifically shown, 4 is driven to rotate via a gear mechanism by a document conveying motor driven and controlled by a control unit.

FIG. 8A shows the vicinity of the downstream end of the document 4 inserted in the document insertion guide 61 in the transport direction.
As shown in detail in (b), the document insertion guide 61
And a document separation roller 65 for taking out the document 4 from above.
A separating piece 66 made of, for example, silicon rubber having a large surface friction coefficient is provided to separate the pieces one by one. The separation piece 66 is in contact with the outer periphery of the document separation roller 65 in a state where the separation piece 66 is inclined from the feeding direction of the document 4.

The continuous paper guide 63 of the document insertion guide section 61 is provided with a film-like extension plate 67 at the front end thereof, the front end of which extends to the vicinity of the separation piece 66. The extension plate 67 comes into contact with a substantial center of the conveyed document 4 in the width direction, and supports and guides the document 4 in a well-balanced manner. As a result, it is possible to prevent a document having a curled leading end from being caught on the document separating roller 65 and a plurality of documents 4 located on the lower side from being in a reverse wedge shape. Therefore, the plurality of originals 4 do not contact the original separation roller 65 at the same time. Here, the extension plate 67 is made of a flexible synthetic resin having a surface with a sufficiently small coefficient of friction so that the lowermost one of the plurality of stacked documents 4 can be smoothly slid to a position where the lowermost document 4 comes into contact with the document separation roller 65. Film (5 / 180mm thick)
PET guide) and the paper guide 6
A base end portion is adhered to a distal end portion of No. 3.

The separating piece 66 includes an urging means for urging the separating piece 66 toward the document separating roller 65.
A leaf spring 68A, a part of which is in contact with the upper side surface of the separation piece 66, is provided, and a block-shaped anti-vibration rubber 69 is adhered and fixed to the leaf spring 68A as anti-vibration means for suppressing the vibration thereof. .

One end of the leaf spring 68A has a separating piece 66.
Support 68 attached to the frame with the base end of
and a bent urging portion 68b which is connected to the other end of the support portion 68a and contacts the separation piece 66 to urge the separation piece 66 toward the document separation roller 65. The vibration damping rubber 69 is provided near one end of the support portion 68a of the leaf spring 68A in order to enhance the vibration performance. On both sides of the separating piece 66, a pair of left and right leaf springs 68B are provided as urging members for securely pressing the original 4 against the original separating roller 65 when the original 4 is thin. Have been. The pair of leaf springs 68B is formed integrally with the leaf spring 68A.

The original reading device 70 is disposed in the middle of the transport path, that is, downstream of the original separating device 60, and has a close contact type image sensor 71 having the same structure as the conventional one.
(CIS). The image sensor 71 reads an image described on the document 4 and supplies an image signal to the control unit.

The image sensor 71 includes an operation panel 8
And has a document width (for example, A4 size) from the near side to the back of the paper so that an image can be read over the entire document 4. A document pressing member 72 that presses the document 4 toward the reading surface 71 a of the image sensor 71 is provided between the image sensor 71 and the operation panel 8.

The original pressing member 72 is connected to the reading surface 7.
1a, a flat portion 72a for pressing a document against the reading surface 71a, and a document 4 formed on the document insertion side and connected to the flat portion 72a.
An inclined surface portion 72b is provided to gradually extend the transport path in a direction opposite to the document transport direction for guiding to 2a. The document pressing member 72 is supported at the upstream end of the member 72 in the document conveyance direction, that is, at the upstream end of the inclined surface 72b in the conveyance direction, so as to be rotatable around an axis orthogonal to the conveyance direction. Further, the document pressing member 72 has a locking portion 72c extending downstream from the flat portion 72a in the transport direction, and a tip end of the locking portion 72c is located within a predetermined range in the engaged hole 2d formed in the frame 2c. Movably in the vertical direction, and the movable range of the document pressing member 72 in the vertical direction is restricted by the engagement relationship.

The original pressing member 72 is provided with a coil spring 74 as a pressing member for pressing the flat portion 72a against the reading surface 71a of the image sensor 71. The coil spring 74 is provided near the downstream end of the flat portion 72 a of the document pressing member 72 in the transport direction, and one end of the coil spring 74 is connected to the document pressing member 7.
2 is engaged with a substantially central portion in a direction orthogonal to the document conveying direction.

The control unit for controlling the facsimile apparatus 1 includes a CPU, a ROM which includes various control programs for recording control and original reading control, and stores a plurality of control programs for controlling the facsimile apparatus 1; R
A microcomputer including an AM is provided.

With the above construction, the cam member 84
Are formed in parallel with the rotation shaft 83 of the first cover 82, and receive a pressing force from the contact engagement portion 85a of the movable rod member 85 to receive the first support frame 86A (the portion on the main body casing 81 side). ) Has a flat surface portion 84b, so that even if it receives a pressing force from the contact engagement portion 85a,
The flat portion 84b of the cam member 84 is
The cam member 84 does not rotate idly in contact with A.
In addition, since the cam member 84 has the restricting portion 84c for restricting the flat portion 84b from being separated from the first support frame 86A by engaging with the first support frame 86A, the flat portion 84b is in the first position. The rotation in the direction away from the support frame 86A is also restricted. Therefore, the cam member 84 does not rotate in any direction due to the engagement between the flat portion 84b and the regulating portion 84c.

Here, the cover opening / closing device of the present invention (first
First, a coil spring 87 having a natural length shorter than the width L inside the support portion 86a is inserted into a support portion 86a formed on the second support frame 86B. Next, the movable rod member 85 is
The through-hole 86c, the coil spring 87, and the through-hole 86d are passed through in this order from the side opposite to the contact engaging portion 85a. Then, the first support frame 86 on which the cam member 84 is mounted
A and the second support frame 86B, on which the movable rod member 85 and the coil spring 87 are mounted,
a so that the leading end surface of a and the no-load surface 84d face each other,
After being mounted at a portion where the rotating shaft 83 penetrates, the rotating shaft 83 penetrates. Therefore, as described above, the coil spring 8 used in the opening / closing device of the first cover 82 is used.
7 has a natural length corresponding to the support portion 86 of the second support frame 86B.
Since the width of the coil spring 87 is shorter than the width L (see FIG. 3) inside the coil spring 87, there is no need to compressively deform the coil spring 87 at the time of assembly, and the support portion 86a has a natural length.
And the coil spring 87 can be easily mounted.

The cam surface 84a of the cam member 84
Has a no-load surface 84d such that the coil spring 87 has a natural length when the first cover 82 is at a predetermined angle with respect to the main body casing 81,
When the first cover 82 is closed, a spring force is applied in a direction to open the first cover 82 in a state where the coil spring 87 is compressed, so that the spring force of the coil spring 87 is used. First
The cover 82 can be easily opened. Also,
First cover 8 whose opening is restricted by stopper member 91
In the open state of FIG. 2, a force for compressing the coil spring 87 must be applied in order to close the first cover 82. Therefore, if no load is applied to the first cover 82, the first cover 82 is closed. 82 will be kept in its open state. Therefore, in the open state, the first cover 82 does not close carelessly.

Further, the temporary fixing hole 91a of the stopper member 91 is engaged with the projection of the second support frame 86B on the first cover 82 side (see FIG. 4), thereby positioning the stopper member 91. In this state, since the screw 93 can be attached and fixed, the stopper member 91 that regulates the opening degree of the first cover 82 with respect to the main body casing 81 can be easily attached.

In the above-described embodiment, the cover opening / closing device according to the present invention is applied to a facsimile machine. However, the present invention is not limited to this, and a printer, a copying machine, or a plurality of functions thereof may be used. It can be used for equipment provided.

[0068]

The present invention is embodied in the form described above, and has the following effects.

According to the first aspect of the present invention, the cam member is formed in parallel with the rotation axis of the cover, and has a flat portion which comes into contact with the main body side portion by receiving a pressing force from the movable member. Even if a pressing force is applied from the movable member without using a mounting means such as a screw, the flat portion of the cam member can be brought into contact with the portion on the main body side to prevent the cam member from idling. .

According to the second aspect of the present invention, the cam member has the restricting portion for restricting the flat portion from separating from the first support frame by engaging with the first support frame.
Rotation of the flat part in a direction away from the first support frame can also be restricted.

According to a third aspect of the present invention, the urging member is a coil spring having a natural length shorter than a width inside the supporting portion and provided in the supporting portion for supporting the movable member, and the cam member is provided with a cover. When the cam member has a predetermined angle with respect to the main body, the urging member has a non-load surface on the cam surface such that the urging member has a natural length. In the opposed state, the coil spring can be easily attached to the supporting portion without pre-compression and with its natural length, and when the cover is closed, the cover is opened with the coil spring compressed. The spring force acts in the direction, and the cover can be easily opened using the spring force of the coil spring.

According to the fourth aspect of the present invention, the cover can be easily assembled in a state where the cover is at a predetermined angle with respect to the main body. That is, by inserting an urging member made of a coil spring having a natural length shorter than its width inside the support portion, and further inserting the movable member into the support portion from the shaft portion side through the through hole, the The cover opening and closing device can be easily assembled without precompression. .

According to the fifth aspect of the present invention, the stopper member is positioned by engaging the temporary fixing hole of the stopper member with the protrusion on the cover side, so that the workability is improved and the stopper for the cover member is improved. A member can be attached.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram of a first cover opening / closing device in which an internal structure is omitted in a facsimile apparatus as an example of an image forming apparatus employing a cover opening / closing device according to the present invention.

FIG. 2 is an explanatory view showing a state in which a first cover is opened in the device.

FIG. 3 is an enlarged view of a main part of a first cover opening / closing device.

FIG. 4 is an explanatory view of attaching a stopper member according to the present invention.

FIG. 5 is an explanatory view showing a second cover opening / closing device according to the present invention.

FIG. 6 is an explanatory view of a main part of a second cover device according to the present invention.

FIG. 7 is an explanatory diagram of an internal structure of the facsimile apparatus according to the present invention.

FIG. 8A is an explanatory diagram of a sheet separating device and a document reading device provided in the facsimile apparatus according to the present invention, and FIG.
FIG. 4 is a view of the separation piece as viewed from below.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Facsimile apparatus 81 Main body casing 82 First cover 83 Rotation shaft 84 Cam member 84a Cam surface 84b Flat surface portion 84c Restriction portion 84d No load surface 85 Movable rod member 85a Contact engagement portion 85b Shaft portion 86A First support frame 86B Second support frame 91 Stopper member 91a Temporary fixing hole

Claims (5)

[Claims] 1. A cover opening / closing device in which a cover is supported on a main body via a rotary shaft so as to be openable and closable, wherein: a cam member provided on the main body side and having a cam portion; A movable member having a contact portion that contacts the cam portion; and a biasing member that biases the movable member in a direction in which the contact portion contacts the cam portion of the cam member. A cover opening / closing device, wherein the cover opening / closing device has a flat portion formed parallel to the rotation axis and abutting against a portion on the main body side by receiving a pressing force from the movable member. 2. The apparatus according to claim 1, further comprising first and second support frames provided on the main body and the cover so as to be rotatable via the rotation shaft, wherein a cam member is provided on the first support frame by the rotation shaft. ,
A movable member is provided on each of the second support frames, and the cam member further controls engagement of the cam member with the first support frame to prevent the flat portion from separating from the first support frame. Claim 1 having a portion
A cover opening / closing device as described in the above. 3. The biasing member is a coil spring having a natural length shorter than an inner width of the support portion and provided in a support portion that supports the movable member. 3. The cover opening / closing device according to claim 1, wherein the cam surface has a no-load surface such that the biasing member has a natural length when the predetermined angle with respect to the main body. 4. The movable member includes a shaft portion around which a coil spring is wound, and an engagement portion having a substantially elliptical cross section connected to an end of the shaft portion and engaged with an end of the coil spring. The cover opening / closing device according to claim 3, wherein a through hole through which only the engaging portion passes is formed in the support portion. 5. A stopper member connecting the cover and the main body and having a temporary fixing hole, and a projection provided on the cover side and engaged with the temporary fixing hole of the stopper member. The cover opening / closing device according to any one of claims 1 to 4, wherein the cover opening / closing device is provided.