JPH0419532B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Application of the Invention) The present invention relates to a document pressure plate opening/closing device in, for example, a copying machine.

(Background Art) A support member is attached to the copying machine main body side so as to rotate in the same direction as the opening/closing direction of the document pressure plate, and the support member is biased in the opening direction between this support member and the copying machine main body side. A conventional document pressure plate opening/closing device includes an elastic means for closing the document pressure plate and a document pressure plate attached to the free end side of the support member so as to rotate in the opposite direction to the support member. When doing so, it is necessary to prevent the original pressure bonding plate from turning over using the pivot point relative to the support member as a fulcrum, or to prevent the document pressure bonding plate from pivoting relative to the support member when the document is thick like a book. In order to invert the document so that it is parallel to the document pressure bonding plate by using the point as a fulcrum, a control means is required to control the inversion of the document pressure bonding plate relative to the support member.

Conventionally, this control means has used a crank means made up of a plurality of members, or a locking means that locks and releases the document pressure plate depending on its opening angle, but both have complicated structures. Therefore, there are problems in that the manufacturing cost is high and there is a limit to the angle at which the document pressure plate can be reversed with respect to the support member.

(Technical Problem) In order to solve the above-mentioned problem, the present invention has a mechanism that normally prevents the document pressure plate from being reversed with respect to the supporting member, but allows this reverse when the document is thick like a book. It is an object of the present invention to provide a document pressure plate opening/closing device equipped with a control means having a simple structure.

(Technical Means) In order to achieve the above-mentioned technical problem, the present invention has a supporting member attached to the main body of the copying machine so as to rotate in the same direction as the opening/closing direction of the document pressure plate, and the supporting member and the copying machine An elastic means for biasing the support member in the opening/closing direction is provided between the support member and the main body, and a document pressure plate is attached to the free end side of the support member via a hinge pin so as to rotate in the opposite direction to the support member. In the case where the crank member is rotatably attached to the hinge pin, the point of action of the elastic means acts on one end of the crank member beyond the pivot point, and the point of action of the elastic means acts on the other end. the document pressure bonding plate is rotatably mounted via a fixing pin at a position different from the pivot position of the hinge pin;
Normally, the original pressing plate is rotated and biased in the direction in which it overlaps the support member through the elastic means and the crank member, but when the original is thick like a book, the elastic means The document pressure bonding plate is configured to allow inversion against elasticity and to horizontally cover the three-dimensional document.

(Function) With the above-mentioned configuration, the document pressure plate is always rotated and biased in the direction in which it overlaps the support member with a simple structure, so even if the document pressure plate is used and the hand is released, it can be easily reversed. If the document is thick like a book, you can apply the document pressure plate to the document and push up the front side of the document a little forcefully.
Using the principle of a lever using a crank member, the document pressure plate is reversed against the elastic force of the elastic means and placed in a horizontal position with respect to the document, and the reversing operation is limited depending on the thickness of the document. There is no such thing.

(Embodiment) According to the drawings, a mounting member 1 having both side plates 1a, 1a is removably mounted on a rear upper plate a of a main body A of a copying machine via a mounting button 2. The mounting member 1 may be fixed onto the rear upper plate a with screws or the like, or may be constructed integrally with the rear upper plate a. A support member 4 has one end portions of both side plates 4a, 4a rotatably attached to one side of the mounting member 1 via a hinge pin 3. On the free end side of this support member 4, a convex control member 5 having mounting plates 5b, 5b on both sides has both side plates 5a, 5a rotatably attached by hinge pins 7, 7. The rear end portion of the document pressure bonding plate B is fixed to the mounting plates 5b, 5b of the control member 5. Note that this control member 5 may be constructed integrally with the document pressure bonding plate B. A crank member 8 is fixed to the pivoting side of the control member 5 by a fixing pin 9, and this crank member 8 is rotatably pivoted to the hinge pins 7, 7. Incidentally, this crank member 8 may be configured as a pair with the control member 5 or the document pressure bonding plate B. A guide member 12 configured to be freely fit and retractable is suspended between pressure receiving pins 10, 10 attached to the side beyond the fulcrum of the crank member 8 and a fixing pin 11 provided on the side of the mounting member 1. Along with being
A compression coil spring 13, which constitutes an elastic means by winding the guide member 12, is attached to the pressure receiving pin 10,
10 and the fixing pin 11.

Therefore, when the original pressure bonding plate B is closed, the support member 4 and the control member 5 are in a mutually folded state relative to the mounting member 1, as shown in FIGS. 1 and 2. . When the document pressure bonding plate B is opened from this state, the back of the control member 5 comes into contact with the back of the support member 4, so that the document pressure bonding plate B is opened together with the support member 4 using the hinge pin 3 as a fulcrum. At the same time, the distance between the fixing pin 11 and the pressure receiving pins 10, 10 changes and becomes longer, so the guide member 12 expands in the longitudinal direction, and at the same time, the elasticity of the compression coil spring 13 changes, so that when the hand is released, the original pressure bonding plate The rotational torque generated by B around the hinge pin 3 and the compression coil spring 1 that acts in a direction to cancel this torque.
It stops when the elasticity of No. 3 is balanced, and as shown in FIG. 4, it is held without falling naturally. The allowable range for stably holding the document pressure bonding plate B at this intermediate opening angle is the hinge pin 3.
If a friction function is provided to the abutment portion between the mounting member 1 and the support member 4, which are connected together, the friction will increase accordingly.

When you release your hand from the opened original pressing plate B, the original pressing plate B appears to turn over along with the control member 5 about the hinge pin 7; Due to the elasticity of the compression coil spring 13 having one point of action on the pressure receiving pins 10, 10 provided at the
The original pressure bonding plate B is rotationally biased together with the control member 5 in the clockwise direction, which is the direction in which it overlaps with the support member 4.
It maintains integrity with the support member 4 without being reversed.

The rotational torque of the document pressure bonding plate B decreases as it is opened, and the elasticity of the compression coil spring 13 is greater than a certain opening angle, so that it bounces up, so the elasticity of the compression coil spring becomes zero from near 90 degrees. It's elaborate.

When the original pressure bonding plate B is closed, the compression coil spring 13 is compressed, and the document pressure bonding plate B, together with the control member 5, receives a force that attempts to rotate counterclockwise around the hinge pin 7 as a fulcrum, so that the document pressure bonding plate B is in the fully closed position. When pressed in the closing direction, the compression coil spring 13 has a weak elasticity at first, so the original pressure bonding plate B rotates slightly counterclockwise together with the control member 5, but soon the compression coil spring 13 becomes elastic. It is pushed back and closed integrally with the support member 4.

As shown in FIG. 5, when the document is a thick 3D document C like a book, when the document pressure plate B is closed, a part of it initially comes into contact with the corner of the 3D document C. , Apply a little more force and press the document pressure plate B.
When the front side is pushed down, the document pressure bonding plate B is reversed counterclockwise together with the control member 5 against the elasticity of the compression coil spring 13 according to the boat principle, and becomes horizontal with respect to the three-dimensional document C. This inversion allowable range is not limited by the thickness of the three-dimensional original C. When the force pushing down the front side of the original pressing plate B rotated counterclockwise is removed or when the three-dimensional original C is removed, the control member 5 is supported by the elasticity of the compression coil spring 13 via the crank member 8. Since it is pushed clockwise, which is the direction in which it overlaps with the member 4, the control member 5 and the document pressure bonding plate B rotate clockwise as well, and are folded and integrated with the support member 4.

(Effects) Since the present invention is constructed as described above, it is possible to perform the opening/closing operation for the original pressing plate as a normal original pressing plate opening/closing device and the stable stopping and holding operation for the original pressing plate at an intermediate opening angle with a simple structure. This method allows you to easily cover a thick three-dimensional document like a book in a horizontal position with a document pressure bonding plate to prevent exposure leakage to the outside and external light from entering the inside of the machine as much as possible. It is something that can be done. At this time, there is an advantage that there is no particular restriction on the range in which the original pressure bonding plate can be reversed with respect to the three-dimensional original.

[Brief explanation of drawings]

The drawings show one embodiment of the present invention, and FIG. 1 is a partially sectional side view thereof, FIG. 2 is a plan sectional view thereof, and FIG.
The drawings are a sectional view taken along the line A--A in FIG. 2, FIG. 4 is a side sectional view of the document pressure plate when opened, and FIG. 5 is a side sectional view showing an example of its use. A... Copying machine body, B... Original pressure bonding plate, C...
Three-dimensional manuscript, 1... Mounting member, 3... Hinge pin,
4... Support member, 5... Control member, 7, 7... Hinge pin, 8... Crank member, 9... Fixed pin, 10... Pressure receiving pin, 12... Guide member, 1
3... Compression coil spring (elastic means).

Claims (1)

[Claims] 1. A supporting member is attached to the copying machine main body side so as to rotate in the same direction as the opening/closing direction of the original pressure bonding plate, and elastic means is provided between the supporting member and the copying machine main body side for biasing the supporting member in the opening direction. and a document pressure bonding plate is pivotally attached to the free end of the support member via a hinge pin so as to rotate in a direction opposite to the support member, wherein a crank member is further rotatably attached to the hinge pin. The elastic means acts on one end of the crank member beyond the pivot point, and the document pressure plate is attached to the other end of the crank member at a position different from the pivot point of the hinge pin. Normally, the original pressing plate is rotatably biased through the elastic means and the crank member in a direction in which it overlaps with the supporting member, but when the original is like a book, In the case of a thick document, the original pressing plate is configured to allow the original pressing plate to be reversed against the elasticity of the elastic means, and to horizontally cover the three-dimensional original. Device.