JP2002014496A - Hinge mechanism for document feeder - Google Patents

Abstract

PROBLEM TO BE SOLVED: To secure linking strength between a still supporting frame 31 and a leg part 30. SOLUTION: This hinge mechanism for a document feeder 2 is constituted of a pair of hinge bodies 4 and 6 disposed at the rear end of the document feeder 2 and attached to the rear end of a copying machine body 102 so that the document feeder 2 may be supported to freely rotate between a closing position and an opening position. The hinge body 4 is equipped with the leg part 30, the still supporting frame 31 disposed at the upper end of the leg part 30, a rotary supporting frame 40 which is coupled with the frame 31 so as to freely rotate through a rotary shaft 46 and by which the rear end of the document feeder 2 is supported, and a compression coil spring 47 disposed between the frames 31 and 40. The frame 31 and the leg part 30 of the hinge body 4 are integrally formed of one common member.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a closed position for covering an upper surface of an image forming machine main body via a hinge mechanism at a rear end portion of the image forming machine main body in an image forming machine such as an electrostatic copying machine, a laser printer, a facsimile or the like. The present invention relates to a hinge mechanism in a document feeder which is mounted so as to be rotatable between the document feeder and an open position for opening an upper surface of an image forming apparatus main body.

[0002]

2. Description of the Related Art An image forming machine such as an electrostatic copying machine is provided with a document conveying device. The document feeder is provided with a hinge mechanism for pivotally supporting the document feeder between a closed position for covering the upper surface of the copying machine main body and an open position for opening the upper surface of the copying machine main body. This hinge mechanism is composed of a pair of hinge bodies disposed at the rear end of the document feeder and mounted at the rear end of the copying machine main body. Support holes are formed at the rear end of the copying machine main body at intervals in the left-right direction. Each of the hinge bodies has a leg inserted and supported in a corresponding support hole, a stationary support frame disposed at an upper end of the leg, a pivotally connected pivotally connected to the stationary support frame via a pivot shaft, and document transport. The apparatus includes a swing support frame on which a rear end of the device is supported, and a compression coil spring disposed between the stationary support frame and the swing support frame.

[0003] In each of the hinge bodies, the stationary support frame and the leg are formed of steel plates, which are separate members, and are integrally fixed to each other by fixing means such as bolts and nuts or welding. The leg has a front wall and a pair of side walls, and has a channel shape opened rearward.
At the upper end of each of the side wall portions, a mounting flange portion extending in the left-right direction of the document feeder is formed. The stationary support frame
It has a bottom frame portion and a pair of side frame portions, and has a channel shape opened upward. The stationary support frame has its bottom frame portion closely attached to the mounting flange portion of the leg portion, and is integrally fixed to each other by fixing means such as bolts and nuts or welding, so that the stationary support frame is integrally formed with the leg portion. It is fixed. The leg is disposed at an intermediate portion in the left-right width direction of the bottom frame of the stationary support frame. The turning support frame includes a ceiling frame portion and a pair of side frame portions, and has a channel shape opened downward. The space between the side frame portions of the revolving support frame is formed wider than the space between the side frame portions of the stationary support frame. The revolving support frame is disposed so as to cover the stationary support frame from above and the side frame portion of the revolving support frame covers the side frame portion of the stationary support frame from both sides, and each of the side frame portions is connected via the revolving shaft. Is connected to the stationary support frame via the pivot shaft so as to be pivotable. The rear end of the document feeder is connected to and supported by the ceiling frame of the turning support frame in each of the hinge bodies. A front wall portion is formed on the front side of the turning support frame.
The front wall is formed by bending a ceiling frame and a pair of side frames. The horizontal axis is fixed between the side frame portions of the stationary support frame and at a lower position spaced forward of the turning shaft portion. A compression coil spring is disposed between the front wall of the turning support frame and the horizontal axis of the stationary support frame via a retainer. The retainer is arranged to hold the rear end of the compression coil spring, and its rear surface is pressed against the horizontal axis of the stationary support frame. The rear surface of the retainer is slidable so that the pressure contact position with respect to the horizontal axis changes in response to the turning operation of the turning support frame.

In the document feeder, each leg of the hinge body is inserted and supported in a corresponding support hole provided at the rear end of the copying machine main body, so that it can pivot with respect to the copying machine main body. Be attached. In a state where the document feeder is located at the closed position, the turning support frame is located at a horizontal position extending perpendicularly to the front and rear direction with respect to the leg. Since the compression coil spring urges the turning support frame to turn around the turning axis in the closing direction with respect to the stationary supporting frame, the document feeder is pressed against the upper surface of the copying machine main body and positioned. The compression coil spring is in the most compressed state. The document feeder is turned in the opening direction by the user's hand, and the document feeder urges the turning support frame to turn in the opening direction about the turning axis with respect to the stationary support frame when the hand is released. The biasing force of the compression coil spring overcomes the rotational moment in the closing direction due to the original weight of the document feeder and is kept at the minimum angle position of the open position, or the rotational moment in the closing direction due to the original weight of the document transporter causes If the original conveying device is lifted beyond the neutral position, which is a boundary position of whether the original conveying device can be turned to the closed position by overcoming the urging force, the original conveying device is held at an arbitrary open position even if the user releases his / her hand. The revolving support frame is inclined with respect to the horizontal position so that its front end is separated upward from the upper surface of the copying machine body.

[0005]

As described above, the document feeder is turned in the closing direction from the open position against the urging force of the compression coil spring, and moves downward from the neutral position to the closed position. When positioned, the turning support frame is positioned at a horizontal position orthogonal to the front-rear direction with respect to the legs. In the state where the document feeder is located at the closed position, the compression coil spring moves the turning support frame about the turning axis with respect to the stationary support frame, in contrast to the state where the document feeder is above the neutral position. Since the document feeder is urged to rotate in the closing direction, the document feeder is operated by both the urging force of the compression coil spring and the rotational moment in the closing direction due to its own weight.
It is positioned by being pressed against the upper surface of the copying machine body. Since the compression coil spring is in the most compressed state, the maximum spring force acts in a direction that substantially separates the turning support frame and the horizontal axis of the stationary support frame in the front-rear direction. This maximum spring force tends to act to lift (lift) the rear end of the stationary support frame upward from the upper end of the leg, and the rear end of the document feeder with the document feeder closed. It has been found by researches of the present invention and the like that the surface slightly emerges. Further, as described above, since the stationary support frame and the leg are formed from separate members, the strength of the joint portion is not sufficiently ensured, as described above. It has also been found from the study of the present invention and the like that it is attributable to the formation of gaps or deformations, though slightly, between them. If the phenomenon occurs in which the rear end of the document feeder rises, the opening and closing operation of the document feeder may not always be performed stably. Further, in the document transport device of the form in which a part of the document transport path of the document transport device is formed in cooperation with a partial region of the upper surface of the copying machine main body and defines the image reading position, If the phenomenon occurs in which the rear end of the document feeder rises, the guide member provided on the document feeder side and the glass plate provided on the copier body side are located at the image reading position. Thus, the gap for passing the document changes in the front-rear direction and cannot be kept constant, and a desired image cannot be stably obtained. In order to solve the above-mentioned problems, it is also conceivable to increase the thickness of the steel plate constituting each of the stationary support frame and the leg, the overall size, and the like to enhance the overall rigidity. It becomes large, and therefore leads to significant weight increase and cost increase.
This is an unacceptable means.

Generally, in a document feeder,
At one end in the left-right direction, a document conveyance path for conveying a document, various rollers, a paper feed motor, a conveyance motor, and the like are arranged in a concentrated manner. I do. Therefore, the load acting on the hinge body disposed on the one end side is considerably larger than the load acting on the hinge body disposed on the other end side. As mentioned earlier,
The stationary support frame has its bottom frame portion disposed in close contact with the mounting flange portion of the leg portion, and is fixed to each other integrally by fixing means such as bolts and nuts or welding.
It is integrally fixed to the leg. The leg is disposed at an intermediate portion in the left-right width direction of the bottom frame of the stationary support frame. Due to such a connection configuration, the bottom frame portion of the stationary support frame is positioned so as to protrude in the left-right direction from both side surfaces of the leg portion, and between the bottom frame portion of the stationary support frame and both side surfaces of the leg portion. Has two right angles. Due to the fact that the center of gravity of the document feeder is biased toward one end in the left-right direction as described above,
During the opening / closing operation of the document feeder, an eccentric load acting on the hinge body in the left-right direction is inevitably generated.
Due to this, if the hinge body disposed at one end where the center of gravity of the document feeder exists is configured as described above, the load acting on the hinge body is large, Excessive stress concentrations may be created at either of the two right angles, and therefore strength and durability may not be guaranteed. In order to solve such a problem, as described above, means for increasing the rigidity of each of the stationary support frame and the legs may be considered, but this is a practical problem as described above.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a novel document feeder capable of sufficiently securing the connection strength and durability between a stationary support frame and a leg included in a hinge body with a simple configuration. Is to provide a hinge mechanism.

Another object of the present invention is to provide a novel document feeder capable of reliably preventing the rear end of the document feeder from rising when the document feeder is closed with a simple configuration. The purpose is to provide a hinge mechanism.

It is another object of the present invention to provide a novel hinge mechanism for a document feeder, which enables a stable opening and closing operation of the document feeder at all times.

Still another object of the present invention is to form a partial area of a document transport path of a document transport apparatus in cooperation with a partial area of an upper surface of an image forming apparatus main body and define an image reading position. In the document feeder in the form, a gap for passing the document formed at the image reading position is always kept constant in the front-rear direction, and a new document feeder that ensures that a desired image is stably obtained is provided. The purpose is to provide a hinge mechanism.

[0011]

According to the present invention, a document feeder is pivotally supported between a closed position covering an upper surface of an image forming machine main body and an open position opening an upper surface of the main body. The document feeder includes a plurality of hinges disposed at a rear end of the document feeder and attached to a rear end of the main body. At least one hinge body is provided at a support disposed at the rear end of the main body. A leg inserted into and supported by the hole, a stationary support frame disposed at an upper end of the leg, and a pivotally connected to the stationary support frame via a pivot shaft to support a rear end of the document feeder. A hinge mechanism for a document feeder, comprising: a revolving support frame; and a spring means disposed between the stationary support frame and the revolving support frame, wherein the at least one hinge body includes a stationary support frame. The leg is integrally formed from one common member. The hinge mechanism of the draft conveying apparatus, is provided.

The plurality of hinges are constituted by a pair of hinges disposed at the rear end of the document feeder at an interval in the left-right direction, and the stationary support frame and the leg are formed of one common member. The integrally formed hinge body is one of a pair of hinge bodies, the center of gravity of the document feeder is present at one end in the left-right direction of the document feeder, and the one hinge body is Disposed at the one end side where the center of gravity exists,
Is preferred. A stationary support frame and a leg provided on a hinge body integrally formed from one common member, a left-right single surface of the leg, and a left-right single surface of the stationary support frame; The one side of the same side as the one side of the portion is formed so as to be positioned on a common plane, and the one side of the leg and the stationary support frame positioned on the common plane is configured to move the document conveying device from the front. When viewed, it is preferably positioned on or near a vertical line passing through the center of gravity.
A stationary support frame and a leg provided on a hinge body integrally formed from one common member, a left-right single surface of the leg, and a left-right single surface of the stationary support frame; Preferably, the one side of the part on the same side as the one side is formed so as to be located on a common plane. The one member of the hinge body in which the stationary support frame and the leg are integrally formed from one common member is made of one metal plate, and the leg extends straight with a constant width in the left-right direction. The front wall,
A pair of side walls formed to extend from both ends of the front wall to the rear side at right angles to and parallel to the front wall, and the stationary support frame includes one of the legs. One side frame portion formed by extending the side wall portion further straight from the upper end thereof, and the other side wall portion of the leg portion from the one side frame portion at a right angle to the other side wall portion from the upper end thereof. A bottom frame portion bent so as to extend straight in a direction away from the bottom frame portion, and the other bent portion formed so as to extend parallel to one side frame portion at a right angle to the bottom frame portion from the tip of the bottom frame portion. It is preferable that an outer surface of one side wall of the leg and an outer surface of one side frame of the stationary support frame be positioned on a common plane. Left and right sides of the leg provided on a hinge body in which the stationary support frame and the leg are integrally formed from one common member, and both sides of the stationary support frame in the left and right direction are respectively common. It is preferably formed so as to be positioned on the plane of.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A preferred embodiment of a hinge mechanism for a document feeder constructed according to the present invention will be described below in more detail with reference to the accompanying drawings. Referring to FIGS. 1 and 2, a copying machine 100 showing only a part thereof includes a copying machine body 102 having a rectangular parallelepiped shape. An original conveying device 2 is mounted on the upper surface of the copying machine main body 102. The document feeder 2 is rotatable between a closed position for covering the upper surface of the copying machine main body 102 and an open position for opening the upper surface of the copying machine main body 102 via a hinge mechanism at the rear end of the copying machine main body 102. It is installed. The hinge mechanism includes a pair of hinge bodies 4 and 6 attached to the rear end of the document feeder 2 at intervals in the left-right direction when the document feeder 2 is viewed from the front. The hinge bodies 4 and 6 will be described later in detail. The image forming means, the image reading device, and other various devices and devices provided in the copying machine main body 102 may use a known configuration, and do not form a feature of the present invention. Therefore, the description is omitted.

The document feeder 2 includes a pickup roller 8
A pair of separation rollers 10 disposed downstream of the pickup roller 8, a pair of registration rollers 12 disposed downstream of the pair of separation rollers 10, and a pair of registration rollers 12
And a discharge roller pair 14 arranged on the downstream side of the discharge roller. The pickup roller 8, the separation roller pair 10, the registration roller pair 12, and the discharge roller pair 14 are arranged in this order from the upstream to the downstream along the document conveying path 15 of the document conveying device 2. A document feed table 16 is provided on the extension of the upstream end of the document conveyance path 15, and a document discharge tray 18 is provided on an extension of the downstream end of the document conveyance path 15. The document discharge tray 18 is located on the document feed table 16.
It is arranged vertically below. A partial area of the document conveying path 15 is formed in cooperation with a partial area on the upper surface of the copying machine main body 102 and defines an image reading position P. A registration roller pair 12 is disposed upstream of the image reading position P, and a discharge roller pair 14 is disposed downstream of the image reading position P. The document conveyance path 15 is curved so as to be substantially inverted between the separation roller pair 10 and the image reading position P.

The separation roller pair 10 includes a driven roller (paper feed roller) 10a and a separation roller 10b. The separation roller 10b is drivingly connected to a paper feed drive unit (not shown) including a paper feed motor composed of an electric motor via a torque limiter (not shown). In order to prevent double feeding of originals after the first eye, a reversing torque is applied. Pickup roller 8 is a separation roller pair 1
The driven roller 10a of the separation roller pair 10 is driven and connected to the driven roller 10a via a toothed pulley and a toothed belt. The registration roller pair 12 includes a driven roller 12a and a driven roller 12b. Discharge roller pair 14
Is composed of a driven roller 14a and a driven roller 14b.

A set document pressing plate 20 is disposed below the pickup roller 8 in the vertical direction. The set original pressing plate 20 is a non-operating position indicated by a solid line in FIG. 2 by a paper feeding solenoid (not shown) and an operating position for pressing the leading end of the original set on the original feeding table 16 toward the pickup roller 8. (In FIG. 2, 2
(A position indicated by a dashed-dotted line). At a position immediately downstream of the pickup roller 8, a document stop wall 22 that defines the position of the leading edge of a document set on the document feed table 16 is provided. A paper feed sensor S that can detect the leading edge or the trailing edge of the document is provided downstream of the separation roller pair 10. The paper feed sensor S can function as a sensor for detecting the leading edge of the document or as a sensor for detecting the trailing edge of the document that has exited the nip portion of the separation roller pair 10. The paper feed sensor S is constituted by an optical reflection type sensor. The driven roller 10a of the separation roller pair 10 is drivingly connected to the paper feed driving means via its support shaft, and the driven rollers 12a and 14a of the registration roller pair 12 and the discharge roller pair 14 have support shafts respectively. It is drivingly connected to a transport drive unit (not shown) including a transport motor composed of an electric motor via the motor.

A glass plate 104 is disposed so as to extend horizontally in a relatively large area on the upper surface of the copying machine main body 102, and an original pressing plate 24 is provided in an area corresponding to the glass plate 104 in the original feeder 2. It is arranged. For example, when reading an image of a document such as a book, the document feeder 2 is opened and the document surface is brought into contact with the glass plate 104. In this case, the optical system of the image reading device moves to read an image on the document. A glass plate 106 having a horizontal upper surface and a guide member 26 arranged to face the glass plate 106 with a predetermined gap therebetween are provided at the image reading position P of the document conveying path 15. The glass plate 106 is arranged so as to extend in the front-rear direction of the copier main body 102 with a constant width at the image reading position P at the left end of the copier main body 102. In addition, the guide member 26 is connected to the
Are arranged to extend in the front-rear direction of the document feeder 2 at a position corresponding to the glass plate 106. A predetermined gap is formed between the horizontal lower surface of the guide member 26 and the horizontal upper surface of the glass plate 106. The upper surface of the glass plate 106 defines the lower surface of the document conveying path 15 at the image reading position P,
The lower surface of the guide member 26 defines the upper surface of the document conveying path 15 at the image reading position P. Therefore, the original transport path 1
5 is formed in cooperation with a partial region on the upper surface of the copying machine main body 102 (a partial region other than the region where the glass plate 104 is disposed) and sets the image reading position P. Stipulates. The predetermined gap between the glass plate 106 and the guide member 26 is defined so that a document having a thickness within at least a predetermined range can pass through the image reading position P while being held in a substantially horizontal posture. Have been.

As will be described later, when the document feeder 2 is positioned at the closed position, a document is set on the document feed table 16 and a copy start key (not shown) provided on the copying machine main body 102 is turned on. Then, the set document pressing member 20 is moved by a solenoid (not shown) as shown in FIG.
At the action position indicated by the two-dot chain line.
The document set on the document feed table 16 is pressed against the pickup roller 8 with a predetermined pressure. The driven roller 10a of the separation roller pair 10 is driven to rotate by the operation of the sheet feeding driving unit (not shown), and the pickup roller 8 is also driven simultaneously. Document feed table 16
The document set on the upper side is usually sent to the separation roller pair 10 from the upper surface side by the pickup roller 8. Of the plurality of originals sent to the separation roller pair 10, only the uppermost one is separated by the separation roller pair 10 and is conveyed toward the registration roller pair 12. After the original is conveyed by a predetermined amount after the leading edge of the original is detected by the paper feed sensor S, the operation of the paper feed driving unit is stopped, and the separation roller pair 1
The rotation of the driven roller 10a of 0 and the pickup roller 8 is stopped, and the primary sheet feeding is completed. The manuscript is
The leading end is pressed against the nip portion of the pair of registration rollers 12 and stopped in a state in which the leading end is bent.

After a lapse of a predetermined time from the end of the primary paper feeding as described above, the driven roller 12a of the registration roller pair 12 and the driven roller 14a of the discharge roller pair 14 are operated by the operation of the transport driving means (not shown). It is driven to rotate.
The document is first conveyed toward the image reading position P by the pair of registration rollers 12, and secondary feeding is started. After the secondary sheet feeding is started, the document is sent to the discharge roller pair 14 after passing through the image reading position P. Next, after being conveyed by the cooperation of the registration roller pair 12 and the discharge roller pair 14, the sheet is finally discharged to the document discharge tray 18 by the discharge roller pair 14.

The image of the document conveyed by the document conveying device 2 as described above passes through the image reading position P, and the image reading means (image reading means included in the image reading device provided in the copying machine main body 102). For example, it is read by a CCD image sensor) and stored as image information by a storage device. The image information stored by the storage device is
Performed in parallel with the above-described transport operation of the document transport device 2;
The image is transferred and fixed on the sheet by the operation of the image forming means provided in the copying machine main body 102. By repeating the image forming operation by the image forming means, the images of all the originals are copied.

Next, the hinge mechanism of the document feeder 2 constructed according to the present invention will be described. As described above, the hinge mechanism includes a pair of hinge bodies 4 and 6 attached to the rear end of the document feeder 2 at intervals in the left-right direction when the document feeder 2 is viewed from the front. . The hinge body 4 is arranged on the left end side of the document feeder 2, and the hinge body 6 is arranged on the right end side. In this specification, the “left-right direction” means the left-right direction (left-right direction in FIG. 1) when the document feeder 2 and the copying machine main body 102 are viewed from the front, and the “front-back direction” Transfer device 2
And the front-back direction (front-back direction in FIG. 1) of the copier main body 102 when viewed from the front.

First, the hinge body 4 will be described. FIG.
As shown in FIGS. 7 to 7, the hinge body 4 includes a leg 30 inserted and supported in one of a pair of support holes 110 (described later) provided at the rear end of the copying machine main body 102; Leg 30
A stationary support frame 31 disposed at the upper end of the
, Which is rotatably connected to the document feeder 2 via a turning shaft 46, and which supports the rear end of the document feeder 2, and which is disposed between the stationary support frame 31 and the turning support frame 40, and A compression coil spring 47, which is a spring means capable of urging the frame 40 to rotate in the direction of the open position of the document feeder 2, and a retainer 48 are provided.

Referring to FIGS. 8 to 10, stationary support frame 31 and leg portion 30, which form part of hinge body 4, are a common metal plate, for example, an appropriate one steel plate. And are integrally formed from the same. The leg portion 30 includes a front wall portion 32 and a pair of side wall portions 33 and 34, and has a channel shape whose cross section is opened rearward. More specifically, the leg portion 30 includes a front wall portion 32 that extends straight at a constant width in the left-right direction, and a rear surface side from both ends of the front wall portion 32 (both left and right ends of the document feeder 2). It includes a pair of side walls 33 and 34 that are bent so as to extend parallel to each other at right angles to the front wall 32. The front wall portion 32 and the side wall portions 33 and 34 are formed to have a substantially band shape. As shown in FIG. 10, the width of the side walls 33 and 34 in the front-rear direction is constant in most regions in the longitudinal direction, but the upper ends of the side walls 33 and 34 are formed to project rearward. , The width in the front-rear direction is wide. The lower end of the upper end protruding rearward is the side walls 33 and 3
Step 33a perpendicular to the tip defining a constant width area of 4
And 34a. The lengths from the lower ends of the side walls 33 and 34 to the steps 33a and 34a are defined to be the same, and the shapes of the side walls 33 and 34 in this region are mutually symmetrical.

The stationary support frame 31 has one side frame portion 35 formed by extending one side wall portion 33 of the leg portion 30 further straight from the upper end thereof, and the other side wall portion 34 of the leg portion 30. A bottom frame portion 36 formed to extend straight from the upper end in a direction perpendicular to the other side wall portion 34 in a direction away from one side frame portion 35, and a bottom frame portion 36 extending from the tip of the bottom frame portion 36. The other side frame portion 37 formed to extend upward at a right angle in parallel with the one side frame portion 35.
And The outer surface of the one side wall 33 of the leg 30 and the outer surface of the one side frame 35 of the stationary support frame 31 are positioned on a common plane P (see FIG. 8). The side frame portions 35 and 37 of the stationary support frame 31 have a substantially symmetric shape. The side frame portions 35 and 37 are formed with rear frame portions 35a and 37a extending from the rear ends thereof at right angles to the side frame portions 35 and 37 and in a direction approaching each other. Holes 35b and 37b having a common axis L extending in the left-right direction are formed at upper end portions near the rear portions of the side frame portions 35 and 37. The holes 35b and 37b are holes for mounting the turning shaft 46. A horizontal axis 38 is fixed between the side frame portions 35 and 37 and at a lower position on the front side than the formation portions of the holes 35b and 37b. A support hole having a common axis with the horizontal axis 38 is formed at a position corresponding to the horizontal axis 38 of the side frame parts 35 and 37, and both ends of the horizontal axis 38 are located at the side frame parts 35 and 3.
7 is held between the side frames 35 and 37 by being pressed into the support holes. Both ends of the horizontal axis 38 are in the side frame 3
Each position is defined so that it may not protrude outside 5 and 37. As described above, the stationary support frame 31 and the leg 3
0 indicates that the stationary support frame 3 is integrally bent from a metal plate, which is one common member, for example, an appropriate steel plate.
It can be said that 1 and the leg 30 constitute an integral leg unit.

Referring to FIGS. 11 to 13, the turning support frame 40 which forms another part of the hinge body 4 is integrally formed by bending a metal plate, for example, an appropriate steel plate. The turning support frame 40 includes a ceiling frame portion 42 and a pair of side frame portions 43 and 44, and has a channel shape opened substantially downward between them. More specifically, the turning support frame 40 includes a ceiling frame portion 42 having a substantially rectangular flat surface.
And a pair of side frame portions that are bent so as to extend downward from both side ends of the ceiling frame portion 42 (side end portions in the left-right direction of the document feeder 2) at right angles to the ceiling frame portion 42 and parallel to each other. 43
And 44. The side frames 43 and 44 are also substantially rectangular. A front frame portion 45 is formed on the front side of the turning support frame 40. The front frame portion 45 is bent so as to extend downward from the front end of the ceiling frame portion 42 at right angles to the ceiling frame portion 42. Most of the front frame 45 on both sides in the left-right direction on the front side is bent so as to extend from the front ends of the side frames 43 and 44 at right angles to the side frames 43 and 44 in a direction approaching each other. It is closely covered with the holding flanges 43a and 44a. Side frames 43 and 44
Are formed with flanges 43b and 44b at the lower end thereof. The flanges 43b and 44b are
Are bent so as to extend from the lower end thereof in a direction approaching each other at right angles to the side frame portions 43 and 44. The rear end of the ceiling frame portion 42 is formed with a turning stopper 42a that extends upward from the flat upper surface of the ceiling frame portion 42 while being inclined upward.
At the center of the front frame portion 45, a positioning projection 45a protruding inside the front frame portion 45 is formed. The projection 45a has a circular periphery. Holes 43c and 44c having a common axis L extending in the left-right direction are formed at upper end portions of the rear end portions of the side frame portions 43 and 44. Hole 43c
And 44c have a size that allows the pivot shaft 46 to pass therethrough. A bearing member 49 is mounted on the ceiling frame portion 42. A projection 49 extending upward is formed on the bearing member 49 which can be integrally formed from an appropriate synthetic resin, and a through-hole 42b is formed in the ceiling frame portion 42, and the projection is press-fitted into the through-hole 42b. Accordingly, the bearing member 49 is mounted inside the ceiling frame portion 42. The bearing member 49 is positioned between the side frame portions 43 and 44 such that both ends have an appropriate gap between the bearing member 49 and the side frame portions 43 and 44. The turning support frame 40 is rotatably supported by the turning shaft 46 via the bearing member 49. The space between the side frames 43 and 44 is formed wider than the space between the side frames 35 and 37 of the stationary support frame 31. The width of the rear end of the ceiling frame 42 is smaller than the space between the side frames 35 and 37 of the stationary support frame 31 (see FIG. 5).

Referring to FIGS. 3, 5 and 6, the turning support frame 40 covers the stationary support frame 31 from above, and the side frame portions 43 and 44 of the turning support frame 40 are The side frame portions 35 and 37 are arranged so as to cover from both sides, and the respective side frame portions are connected to each other via the turning shaft 46, so that the turning support frame 40 moves the turning shaft 46 to the stationary support frame 31. It is pivotally connected and supported via the cable. In a state where the turning support frame 40 is positioned so as to extend perpendicularly to the leg 30, between the inside of the front frame portion 45 of the turning support frame 40 and the horizontal axis 38 of the stationary support frame 31. The size of the turning support frame 40 in the longitudinal direction (front-back direction) is defined so that a predetermined interval is formed. A compression coil spring 47 is disposed between a front frame portion 45 of the revolving support frame 40 and a horizontal axis 38 of the stationary support frame 31 via a retainer 48 having a substantially cap shape. The front end of the compression coil spring 47 is positioned at the peripheral edge of the positioning projection 45 a of the front frame 45, and the other end is housed and retained in the retainer 48. The retainer 48 is large enough to be accommodated in a rectangular space in the turning support frame 40 and is formed to have a substantially rectangular outer peripheral surface. On the rear surface of the retainer 48, there is formed an inclined surface 48a that is linearly inclined from the upper side to the lower side and the front as viewed from the left and right direction when the turning support frame 40 is viewed from the left and right directions. In a state where the revolving support frame 40 is relatively positioned so as to extend perpendicularly to the leg 30, the upper end of the inclined surface 48 a of the retainer 48 is compressed by the compression coil spring 47 so that the horizontal axis 38 of the stationary support frame 31. To the compression coil spring 4
7 is compressed to the maximum, and the turning support frame 40 is maintained in the above state. As described above, the ceiling frame portion 4 of the swing support frame 40
Since the width of the rear end of the ceiling frame 42 is smaller than the space between the side frames 35 and 37 of the stationary support frame 31, the boundary between the wide and narrow portions of the ceiling frame 42 is The stationary support frame 31 is brought into contact with the corresponding upper ends of the side frame portions 35 and 37, and the pivot support frame 40 is prevented from further pivoting in the counterclockwise direction (close direction) in FIG. The rear end of the document feeder 2 is connected to the ceiling frame 42 of the turning support frame 40 of the hinge body 4.

Next, the hinge body 6 will be described. Figure 1
As shown in FIGS. 4, 16 and 17, the hinge body 6 is a leg that is inserted into and supported by the other of a pair of support holes 110 (described later) provided at the rear end of the copying machine main body 102. Part 5
And a pivot support frame 60 that is pivotally connected to the upper end of the leg 50 via a pivot shaft 51 and supports the rear end of the document feeder 2. The leg 50, which can be integrally formed of a suitable synthetic resin, has a solid square shape having a substantially square cross section.
2 is formed to project rearward. A step 50a is formed between the upper end of the rear surface of the leg 50 and the lower end of the upper end 52 at right angles to each other. A boss 53 projecting upward is formed at the rear of the upper end 52 of the leg 50. The turning shaft 51 is mounted in the through hole of the boss 53.

The pivot support frame 60 is pivotally connected to the leg 50 via a pivot 51. 16 and 17
, The symbol L indicates a turning axis. Hinge body 6
Is formed integrally from a metal plate, for example, an appropriate steel plate. The turning support frame 60 is
A bottom frame 62 having a substantially rectangular flat surface and a pair of side frames 63 and 64 are provided, and have a channel shape opened upward. The side frames 63 and 64 are bent so as to extend upward from both ends of the bottom frame 62 (both sides in the left-right direction of the document feeder 2) at right angles to the bottom frame 62 and parallel to each other. ing. The side frames 63 and 64 are
, And extends a predetermined length further rearward, and has a substantially rectangular shape. A front frame portion 65 is provided on the front side of the turning support frame 60.
Are formed. The front frame portion 65 is bent so as to extend upward from the front end of the bottom frame portion 62 at right angles to the bottom frame portion 62. A flange 65 a is formed at the upper end of the front frame 65. The flange portion 65a is bent so as to extend from the upper end of the front frame portion 65 toward the front at right angles to the front frame portion 65. Flanges 63a and 64a are formed at the upper ends of the side frames 63 and 64, respectively. The flange portions 63a and 64a are bent so as to extend from upper ends of the side frame portions 63 and 64 in a direction perpendicular to and separated from the side frame portions 63 and 64, respectively. Flange part 6
5a and the upper surfaces of the flange portions 63a and 64a,
They are positioned on the same plane. Side frames 63 and 64
At the rear end, flange portions 63b and 64b are formed. The flange portions 63b and 64b are connected to the side frame portions 63 and 6 respectively.
4 are bent so as to extend from the rear end in a direction approaching each other at right angles to the side frame portions 63 and 64. In addition,
A turning stopper 53 projecting upward is formed at the rear end of the upper end 52 of the leg 50. The turning of the turning support frame 60 in the opening direction is restricted by the flange portions 63 b and 64 b contacting the turning stopper 53. Flange 65a, Flange 63a of Revolving Support Frame 60 of Hinge Body 6
And 64a, the rear end of the document feeder 2 is connected.

Referring to FIGS. 1, 4 and 15, a pair of channel members 114 are fixed to the frame 112 defining the rear end of the copying machine main body 102 at intervals in the left-right direction. When each open end of the channel member 114 is closed by the frame 112, a support hole 110 is formed between each of the channel members 114 and the frame 112. Each of the support holes 110 is formed to have a substantially square cross section and is positioned to extend linearly in the vertical direction. Document feeder 2
The legs 30 and 50 of the hinge bodies 4 and 6 are removably inserted into and supported by the corresponding support holes 110 so that they can be pivotally mounted on the copying machine main body 102.
Steps 33a and 34a on the side walls 33 and 34 of the leg 30 of the hinge body 4
The legs 30 are held in the corresponding support holes 110 by being placed on the upper end surface of the. The leg 5 of the hinge body 6
The leg portions 50 are held in the corresponding support holes 110 by placing the 0 step portions 50 a on the upper end surfaces of the corresponding channel members 114. The pivot axis L of each of the hinge bodies 4 and 6 is located on a common axis as shown in FIG.

Referring to FIG. 1 and FIG.
1 is positioned at the closed position shown in FIG. 1, the turning support frame 40 of the hinge body 4 is positioned at a horizontal position extending perpendicularly to the leg 30 in the front-rear direction.
The compression coil spring 47 connects the turning support frame 40 to the stationary support frame 3.
Since the document conveying device 2 is urged to rotate about the turning shaft 46 in the closing direction, the document conveying device 2 is pressed against the upper surface of the copying machine main body 102 and positioned. The compression coil spring 47 is in the most compressed state. The document feeder 2 is turned in the opening direction (clockwise in FIG. 7) by the user's hand, and when the document feeder 2 is released, the turning support frame 40 is turned with respect to the stationary support frame 31. The urging force of the compression coil spring 47 for urging the original conveying device 2 to rotate in the opening direction overcomes the rotational moment of the original conveying device 2 in the closing direction due to its own weight, and is held at the minimum angular position of the open position, or the original is conveyed. When the rotational moment in the closing direction due to the weight of the apparatus 2 in the closing direction overcomes the urging force of the compression coil spring 47 and exceeds the neutral position, which is a boundary position at which the document conveying apparatus 2 is turned to the closed position, the document conveying apparatus 2 Even if it is released, it is held at any open position. Swivel support frame 40 in hinge body 4
Is inclined with respect to the horizontal position such that its front end is separated upward from the upper surface of the copying machine main body 102. When the document conveying device 2 (the turning support frame 40) is turned around the turning shaft 46 to the fully opened position shown in FIG. 7 by the user's hand, the turning stopper 42a of the turning support frame 40.
Abuts on the upper ends of the rear frame portions 35a and 37a of the stationary support frame 31 to prevent further rotation, and the document conveying device 2
Even when the user releases his hand, the compression coil spring 47 is held at the fully open position by the urging force (see FIG. 7).

As the revolving support frame 40 is revolved from the closed position to the open position of the document feeder 2, the inclined surface 48 a of the retainer 48 pressed against the horizontal axis 38 of the stationary support frame 31 becomes horizontal. It is slid with respect to the shaft 38. That is, the pressure contact of the inclined surface 48a with respect to the horizontal axis 38 is slid from the upper end to the lower end,
The distance between the point of application of the rotation moment by the compression coil spring 47 and the turning shaft 46, which causes the document feeder 2 to turn in the opening direction, gradually increases, and at the same time, the front frame portion 45 of the turning support frame 40 and the stationary support frame 31. Are gradually separated, the spring force of the compression coil spring 47 is gradually reduced, and furthermore, an operation is performed such that the rotational moment in the closing direction due to the own weight of the document feeder 2 is gradually reduced. .
For this reason, when the document conveying device 2 exceeds the neutral position (not shown) upward, the document conveying device 2 is held at an arbitrary open position even if the user releases his / her hand.

When the document feeder 2 is turned in the closing direction against the urging force of the compression coil spring 47 and is positioned at the closed position below the neutral position, the turning support frame 40 is moved to the leg portion. 30 is positioned at a horizontal position orthogonal to the front-rear direction. In the state where the document feeder 2 is located at the closed position, the compression coil spring 47 causes the turning support frame 40 to move to the stationary support frame 31, as opposed to the state where the document feeder 2 exceeds the neutral position above. Swivel axis 4
6, the document feeder 2 presses the upper surface of the copying machine main body 102 by both the urging force of the compression coil spring 47 and the rotational moment in the closing direction due to its own weight. Being positioned. Since the compression coil spring 47 is in the most compressed state, the maximum spring force acts in a direction substantially separating the turning support frame 40 and the horizontal axis 38 of the stationary support frame 31 in the front-rear direction. As described above, this maximum spring force tends to act to lift the rear end of the stationary support frame 31 upward from the upper end of the leg 30.

As described above, the stationary support frame 31 and the leg 30 of the hinge body 4 according to the present invention are formed integrally from one common member, so that the stationary support frame 31 and the leg 3
There is no joint as in the conventional hinge body in which the “0” is formed from a separate member, and the gap or deformation as described above does not occur. That is, according to the hinge mechanism including the hinge body 4 according to the present invention, it is possible to sufficiently secure the connection strength and durability between the stationary support frame 31 and the leg 30 with a simple configuration. In the embodiment, since the stationary support frame 31 and the leg 30 are configured as a leg unit integrally formed by bending one suitable steel plate, the strength of the leg unit is sufficiently secured by a simple configuration. it can. As a result, with the simple configuration, the phenomenon that the rear end of the document feeder 2 rises when the document feeder 2 is closed is reliably prevented. Further, it is ensured that the opening / closing operation of the document feeder 2 is always performed stably.
Further, as described with reference to FIG. 2, the partial area of the original conveying path 15 of the original conveying apparatus 2 is
In the document feeder 2 formed in cooperation with a partial area on the upper surface of the document feeder 2 and defining the image reading position P, a gap (document feeder 2) for passing the document formed at the image reading position P The gap formed between the guide member 26 disposed on the side of the printer and the glass plate 106 disposed on the copier main body side 104 for document passage) is always kept constant in the front-rear direction, and is thus desired. It is guaranteed that images are obtained stably.

In the illustrated document feeder 2,
In FIG. 1, a document conveying path for conveying a document, various rollers, a paper feeding motor, a conveying motor, and the like are arranged in a concentrated manner at a left end, which is one end in the left-right direction. In FIG. 1, it exists on the left end side. Therefore, the load acting on the hinge body 4 disposed on the left end side is considerably larger than the load acting on the hinge body 6 disposed on the right end side. Due to the fact that the center of gravity of the document feeder 2 is biased toward the left end portion, when the document feeder 2 is opened and closed, an uneven load acting on the hinge body 4 in the left-right direction, particularly in the direction where the center of gravity exists. Is inevitably generated. In FIG. 1, reference numeral G denotes the center of gravity of the document feeder 2, and the hinge body 4 is disposed at the left end where the center of gravity G exists. As described above, since the stationary support frame 31 and the leg portion 30 are integrally formed from one common member, the hinge body 4 has a simple structure that enhances the connection strength thereof, and the above-described eccentric load. Despite the production and the effect of large loads, its connection strength and durability are guaranteed.

In the hinge body 4, the leg 30
Of the stationary support frame 31 and one side of the stationary support frame 31 on the same side as the leg 30 (outside surface of the side frame portion 35). Common plane P
It is formed to be positioned above. And the leg 30 and the stationary support frame 31 positioned on the common plane P
1 is near a vertical line (not shown) that passes through the center of gravity G when the document feeder 2 is viewed from the front.
In the vicinity of the right side of the vertical line. As a result, even when an eccentric load acting on the hinge body 4 in the direction where the center of gravity G exists is generated during the opening and closing operation of the document feeder 2, the influence of the eccentric load is minimized, and Since one surface of each of the stationary support frame 31 and the leg 30 located on the G side is located on the common plane P, stress concentration does not occur as in the related art,
The connection strength and durability of the stationary support frame 31 and the leg 30 are guaranteed. Further, a stable opening and closing operation of the document feeder 2 is always guaranteed. Legs 3 located on a common plane P
When the one surface of the zero and the stationary support frame 31 is positioned on a vertical line passing through the center of gravity G, the above effect is further improved.

It should be noted that one side in the left-right direction of the leg portion 30 (outer side surface of the side wall portion 33) and one side surface in the left-right direction of the stationary support frame 31 on the same side as the one side of the leg portion 30 (side frame portion). The hinge body 4 formed so as to be positioned on the common plane P, regardless of the position in the left-right direction of the rear end of the document feeder 2, Due to the eccentric load in the left and right direction during the opening and closing operation of the transfer device 2, stress concentration does not occur at least on the plane P side, and the connection strength and durability of the stationary support frame 31 and the leg portion 30 are guaranteed. The strength and durability of the hinge body 4 are guaranteed. Further, a stable opening / closing operation of the document feeder 2 is ensured. Instead of such an embodiment, the leg 3 provided on the hinge body 4 in which the stationary support frame 31 and the leg 30 are integrally formed from one common member.
Another embodiment in which both the left and right sides of the stationary support frame 31 and the left and right sides of the stationary support frame 31 are formed so as to be positioned on a common plane is also realized. In this embodiment, stress concentration does not occur due to any unbalanced load in the left-right direction during the opening / closing operation of the document feeder 2, so that the above-mentioned effect is further improved.

In the above embodiment, the one member of the hinge body 4 in which the stationary support frame 31 and the leg portion 30 are integrally formed from one common member is a single metal plate, generally a steel plate. The legs 30 extend straight and have a constant width in the left-right direction, and extend from both ends of the front wall 32 to the rear surface side at right angles to the front wall 32 in parallel with each other. It includes a pair of bent side walls 33 and 34. The stationary support frame 31 is provided on one side wall 3 of the leg 30.
3 is further extended straight from the upper end thereof, and one side frame portion 35 formed by extending the other side wall portion 34 of the leg portion 30 from the upper end thereof at right angles to the other side wall portion 34. The bottom frame 36 is formed so as to extend straight in a direction away from the portion 33, and extends from one end of the bottom frame 36 at right angles to the bottom frame 36 in parallel with one side frame 35. And the other side frame portion 37 formed by bending. The outer surface of one side wall 33 of the leg 30 and the outer surface of one side frame 35 of the stationary support frame 31 are positioned on a common plane P. Such a configuration facilitates practical application, and furthermore, a simple configuration guarantees the connection strength and durability of the stationary support frame 31 and the leg 30, and thus the required strength and durability of the hinge body 4. Guaranteed easily and reliably.

In the illustrated document feeder 2, the center of gravity G is located on the left end side in FIG. 1, and the load acting on the hinge body 4 disposed on the left end side is disposed on the right end side. Since the load applied to the hinge body 6 is considerably larger than that of the hinge body 6, the hinge body 4 disposed on the left end side is configured as described above. On the other hand, the load acting on the hinge body 6 disposed on the right end side of the document feeder 2 is considerably smaller than the load acting on the hinge body 4 disposed on the left end side. No compression coil spring is provided. Therefore, the hinge body 6 is configured relatively easily,
In cooperation with the hinge body 4, the turning operation of the document feeder 2 is smoothly performed.

As described above, the present invention has been described in detail based on the embodiments with reference to the accompanying drawings. However, the present invention is not limited to the above-described embodiments, and does not depart from the scope of the present invention. Various other variations or modifications are possible. For example, in the above embodiment, the hinge bodies 4 and 6 are provided at the rear end of the document feeder 2, but depending on the size and / or weight of the document feeder 2, both of the compression coil springs 47 are provided. There is also another embodiment constituted by the hinge body 4 including the above. Further, depending on the size and / or weight of the document feeder 2, there is another embodiment in which three or more hinges are arranged at the rear end of the document feeder 2. In that case, it is essential that at least one hinge body is constituted by the hinge body 4. Still further, the present invention provides an image forming apparatus such as an electrostatic copying machine, a laser printer, and a facsimile, which is pivotally mounted between a closed position and an open position via a hinge mechanism at a rear end of the image forming machine main body. The present invention relates to the hinge mechanism in the document feeder described above, in addition to the image forming machine, between the closed position and the open position via the hinge mechanism at the rear end of the image reading device body in the image reading device. The present invention is also applied to the hinge mechanism in a document conveying device which is mounted to be freely rotatable. In this case, the “image forming apparatus main body” in the present invention is replaced with the “image reading apparatus main body”.

[0040]

According to the document feeder of the present invention, it is possible to sufficiently secure the connection strength and the durability between the stationary support frame included in the hinge body and the leg with a simple structure. Further, it is possible to reliably prevent the rear end of the document feeder from rising when the document feeder is closed with a simple configuration. Furthermore, a stable opening / closing operation of the document feeder is always possible. Still further, in the document feeder in which a part of the document feed path of the document feeder is formed in cooperation with a part of the upper surface of the copying machine main body and the image reading position is defined. The gap formed at the position for document passage is always kept constant in the front-rear direction, thereby ensuring that a desired image is stably obtained.

[Brief description of the drawings]

FIG. 1 is a schematic front view showing a part of a document feeder and a copying machine having an embodiment of a hinge mechanism according to the present invention.

FIG. 2 is a schematic cross-sectional view showing, on an enlarged scale, a part of the document feeder and the copying machine main body shown in FIG. 1;

FIG. 3 is a front view showing one of the hinge bodies included in the hinge mechanism of the document feeder shown in FIG. 1, and showing a part of the constituent members omitted.

FIG. 4 is a sectional view taken along the line AA in FIG. 1;

FIG. 5 is a top view of the hinge body shown in FIG. 3;

6 is a side view of the hinge body shown in FIG. 3 as viewed from the right side in FIG. 3, including a part of components omitted in FIG. 3;

FIG. 7 is a side view showing another operation mode of the hinge body shown in FIG. 6;

8 is a front view showing a leg unit constituting the hinge body shown in FIG. 3;

FIG. 9 is a top view of the leg unit shown in FIG. 8;

FIG. 10 is a side view of the leg unit shown in FIG. 8 as viewed from the right in FIG. 8;

FIG. 11 is a front view showing a turning support frame constituting the hinge body shown in FIG. 3;

FIG. 12 is a top view of the turning support frame shown in FIG. 11;

13 is a side view of the turning support frame shown in FIG. 11 as viewed from the right in FIG. 11;

FIG. 14 is a front view showing the other of the hinge bodies included in the hinge mechanism of the document feeder shown in FIG. 1;

FIG. 15 is a sectional view taken along the line BB in FIG. 14;

FIG. 16 is a top view of the hinge body shown in FIG. 14;

17 is a side view of the hinge body shown in FIG. 14 as viewed from the right side in FIG.

[Explanation of symbols]

 2 Document Conveyor 4, 6 Hinge Body 30 Leg 31 Stationary Support Frame 32 Front Wall 33, 34 Side Wall 35, 37 Side Frame 36 Bottom Frame 40 Rotating Support Frame 100 Copier 102 Copier Body 106 Glass Plate 110 Support hole G Center of gravity P Plane

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2H012 CB01 CB15 2H076 BA08 5C062 AA02 AA05 AB02 AB17 AB30 AC02 AD02 AD06

Claims (6)

[Claims] 1. A document feeder is disposed at a rear end of a document feeder so as to pivotably support a document feeder between a closed position covering an upper surface of an image forming apparatus main body and an open position opening an upper surface of the main body. A plurality of hinge bodies attached to the rear end of the main body, at least one hinge body is inserted and supported in a support hole provided at the rear end of the main body, A stationary support frame disposed at the upper end of the leg, a pivotable support frame pivotally connected to the stationary support frame via a pivot shaft, and supporting the rear end of the document feeder; A hinge mechanism for the document feeder, comprising: a spring means disposed between the stationary support frame and the leg provided on at least one of the hinge bodies. Integrally formed,
A hinge mechanism for a document feeder, comprising: 2. A plurality of hinge bodies comprising a pair of hinge bodies disposed at a rear end portion of the document feeder at right and left intervals, and one stationary support frame and one leg are common. The hinge body integrally formed from the member is one of a pair of hinge bodies, and the center of gravity of the document feeder is located at one end in the left-right direction of the document feeder, and the hinge 2. The hinge mechanism according to claim 1, wherein the body is disposed on the one end side where the center of gravity exists. 3. The left and right sides of the stationary support frame and the left and right sides of the stationary support frame provided on a hinge body in which the stationary support frame and the legs are integrally formed from one common member. The one side of the leg on the same side as the one side is formed so as to be positioned on a common plane, and the one side of the leg and the stationary support frame positioned on the common plane is a document. 3. The hinge mechanism of the document feeder according to claim 2, wherein the feeder is positioned on or near a vertical line passing through the center of gravity when viewed from the front. 4. A left and right side of the stationary support frame and a left and right side of the stationary support frame provided on a hinge body in which the stationary support frame and the leg are integrally formed from one common member. 3. The hinge mechanism for a document feeder according to claim 1, wherein said leg portion is formed so as to be positioned on a common plane with one surface on the same side as said one surface. 5. One member of a hinge body in which a stationary support frame and a leg are integrally formed from one common member is one member.
A front wall portion extending straight at a constant width in the left-right direction, and extending parallel to each other at right angles to the front wall portion from both side ends of the front wall portion to the rear surface side. The stationary support frame includes a pair of side walls formed so as to be bent, and the stationary support frame includes one side frame formed by further extending one side wall of the leg straight from the upper end thereof; A bottom frame portion formed by bending the other side wall portion of the leg portion so as to extend straight from the upper end thereof in a direction perpendicular to the other side wall portion in a direction away from the one side frame portion, and from a tip of the bottom frame portion. An outer side surface of one of the side walls of the leg and the stationary support frame, the other side frame being bent so as to extend parallel to the one side frame at right angles to the bottom frame. 5. The hinge mechanism of the document feeder according to claim 4, wherein the outer side surface of the one side frame portion is positioned on a common plane. 6. The left and right sides of the stationary support frame and the left and right sides of the leg provided on a hinge body in which the stationary support frame and the leg are integrally formed from one common member. 3. The hinge mechanism of the document feeder according to claim 1, wherein each of the hinge mechanisms is formed so as to be positioned on a common plane.