JPH0588485A - Automatic document feeder - Google Patents

Abstract

PURPOSE:To correct a weight balance, and prevent this side from parting upward due to shocks or vibrations by holding a conveying part vertically/ movably to a hinge stay, and energizing the innermost side of the conveying part upward elastically to the hinge stay. CONSTITUTION:A conveying part having a document conveying belt 41 is held vertically/movably to a hinge stay 50 to support a device body on the innermost side of a copying machine body 1 so as to be capable of making turning motion freely. That is, frame bodies 51F and 51R of the conveying part are held to the hinge stay 50 by means of stepped screws 52 and 53, and thereby, the conveying part has a degree of freedom such as to be movable in the vertical direction to the hinge stay 50. In order to reduce an innermost side load of an automatic document feeder(ADF), a projecting piece 61 is fixed to a movable metal fitting 5b to hold the hinge stay 50, and a tension coil spring 63 is installed between the projecting piece 61 and a projecting piece 62 arranged in the frame body 51R, and the innermost side of the ADF is hoisted up elastically to the hinge stay 50.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic document feeder for automatically feeding a document onto a platen glass of a copying machine.

[0002]

2. Description of the Related Art In recent years, in the field of electrophotographic copying machines, various automatic document feeders (hereinafter referred to as ADFs) have been provided in order to reduce the trouble of document replacement and enhance the copy processing capability. The ADF feeds documents one by one from a tray, sets them at a fixed position on the platen glass, and discharges them from the platen glass after the image scanning is completed.

The ADF is rotatably installed on the back side of the main body of the copying machine by a hinge fitting so that an operator can manually set a document on the platen glass, and the ADF can be opened on the platen glass. On the other hand, in the ADF, the transport belt needs to contact the platen glass uniformly. However, due to component errors and assembly errors, for example, the mounting height of the hinge metal fittings and the platen glass height vary from machine to machine, and the angle difference between the hinge metal fitting mounting surface and the platen glass surface makes the conveyor belt uniform. There is a problem that it does not touch the top.

Conventionally, a spacer is interposed between the hinge metal fitting and its mounting surface during machine setup to adjust the height of the platen glass for each machine, but this is complicated. Therefore, in order to save the labor of height adjustment, it is possible to hold the ADF document transport unit so as to be movable up and down with respect to the hinge stay, and absorb rattling in the height direction.
However, if such a configuration is simply adopted, since a heavy object such as a motor for driving the belt is arranged on the back side of the transport section, the impact or vibration such as opening / closing the copying machine body may cause A
There is a new defect that the front side of the DF rises.

[0005]

SUMMARY OF THE INVENTION Therefore, the object of the present invention is to
It is an object of the present invention to provide an automatic document feeder which does not require height adjustment of the conveying section, which is in contact with the platen glass with good weight balance, and whose front side does not float up due to impact or vibration. In order to achieve the above object, the automatic document feeder according to the present invention holds the document feeder so that it can move up and down with respect to the hinge stay, and the back side of the document feeder is elastically moved upward with respect to the hinge stay. It is characterized by being urged to.

That is, since the transport unit can move up and down, the transport unit is automatically positioned in accordance with the inclination of the platen glass and the transport belt uniformly contacts the platen glass. Moreover, since the back side of the transport section is elastically biased against the hinge stay, the weight balance, which is ubiquitous on the back side, is corrected.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The automatic document feeder (AD) according to the present invention will be described below.
The embodiment of F) will be described with reference to the accompanying drawings. In FIG. 1 and FIG. 2, the ADF 10 is a sheet feeding unit 20.
And the transport section 40 centered on the transport belt 41, and
It is composed of a discharge part 90.

The paper feeding section 20 comprises a document tray 21, a pickup roller 24, separating rollers 25 and 26, and registration rollers 28 and 29. The document tray 21 includes a pair of side regulating plates 22 and a tip stopper 23. Document D is placed in tray 2 with the first page facing downward.
1 is placed on top. When the solenoid 31 is turned on during sheet feeding, the leading end stopper 23 swings downward around the pin 23a as a fulcrum and retracts from the regulation position. The pickup roller 24 is attached to the tip of a lever 27 that is rotatable about a support shaft 25a of the forward separating roller 25 as a fulcrum, and when the paper is fed, the solenoid 31 is turned on to descend and press the upper surface of the document D. .. Forward rotation roller 25
On the other hand, the reverse rotation separation roller 26 is pressed from below with a constant pressing force. The pickup roller 24 and the forward rotation separating roller 25 are rotationally driven in the direction of arrow c by the paper feeding motor 32, and the reverse rotation separating roller 26 is the paper feeding motor 3.
It is rotationally driven in the direction of arrow cr by 2.

The registration rollers 28 and 29 temporarily hold the fed original at the nip portion thereof, and after a predetermined time, the upper roller 28 is rotationally driven in the direction of arrow c by the main motor 45 so that the original is placed on the platen glass 2. Transport to the entrance. The lower roller 29 rotates following the upper roller 28. The conveyor belt 41 is endlessly stretched between the drive roller 42 and the driven roller 43 so as to cover the entire surface of the platen glass 2. Inside the conveyor belt 41,
A large number of backup rollers 44 are rotatably installed to press the belt 41 against the platen glass 2. The conveyor belt 41 is rotationally driven in the direction of arrow c by the main motor 45 via the drive roller 42, and the original document is moved to the reference position O which is the boundary between the scale 3 and the platen glass 2.
Align the trailing edge of the document with and set it.

The reversing / discharging section 90 includes a pinch roller 92.
Reversing roller 91 provided with a and 92b, sheet passing switching claw 9
3, a discharge roller 94, and a discharge tray 95. The reversing roller 91 and the discharging roller 94 are rotationally driven in the direction of arrow c by the reversing / discharging motor 96, and the switching pawl 9
3 is operated by a solenoid (not shown). During the first-side copy processing of a double-sided original, the reversing roller 91 and the switching claw 93 perform an operation for reversing the original. That is, the document being discharged from the platen glass 2 by the rotation of the conveyor belt 41 is rotated and conveyed around the reversing roller 91, and is returned to the platen glass 2 again in the inverted state. At this time, the conveyor belt 41 is rotationally driven in the direction opposite to the arrow c. Switching claw 93 in the discharge mode
Does not operate, and the document is ejected from the reversing roller 91 through the ejection roller 94 onto the tray 95.

Next, the structure for mounting the ADF 10 on the copying machine main body 1 and the structure for supporting the conveying section 40 having the above-described structure and operation will be described with reference to FIGS. ADF1
No. 0 is installed on the upper surface of the copying machine main body 1 so that the conveyor belt 41 is located on the platen glass 2, and the platen glass 2 can be opened by the hinge fitting 5 provided on the back side.
When the operator manually sets the original document on the platen glass 2, it is performed by lifting the entire ADF 10 upward. At this time, the ADF 10 moves up and down with the support shaft 6 of the hinge fitting 5 as a fulcrum.

The magnet 12 is fixed to the front frame 51F of the ADF 10, and the magnet 1 is provided on the main body 1 of the copying machine.
The magnetic plate 4 is installed at a position facing the position 2. ADF
When 10 is closed from the open state, the magnet 12
Adsorbs the magnetic plate 4, and the set becomes reliable. Further, one magnet 12 has a reed switch built therein. This reed switch operates when the magnet 12 attracts the magnetic plate 4, and the device 10 causes the platen glass 2 to move.
Detects that it has been set correctly.

The fixed metal fitting 5a of the hinge fitting 5 is fixed on the copying machine main body 1, and two hinge stays 50 extending toward the front side are attached to the movable fitting 5b. The hinge stay 50 includes frames 51F and 51R of the transport section 40.
Are held by stepped screws 52, 53. Therefore, the transport unit 40 is A or A ′ with respect to the hinge stay 50.
It has the freedom to move in the vertical direction by the amount of clearance. Further, the ADF is provided below the frame bodies 51F and 51R.
Spencers 54, 55 are attached that abut on platen glass 2 when 10 is closed.

When the transport section 40 is in the open state, it is suspended from the hinge stay 50 by its own weight.
When the ADF 10 is completely closed, the magnet 12 is in a state of attracting the magnetic plate 4 as shown in FIG. In this state, the spacers 54 and 55 are grounded on the platen glass 2, and the surface of the conveyor belt 41 is placed parallel to the platen glass 2 at a constant height.

As described above, the transport section 40 is attached to the hinge stay 5.
By adopting the hanging method with respect to 0, even if there is a component error or an assembly error of the hinge metal fitting 5 or the platen glass 2 is slightly inclined, the frame body 51 has a stepped screw 5
By moving up and down within the clearances A and A ′ of 2,53, the transport unit 40 naturally fits on the surface of the platen glass 2. Therefore, unlike the prior art, it is not necessary to finely adjust the height of the hinge fitting 5 with the platen glass 2 by using the spacer when setting up the machine.

However, if the suspension system is adopted, the ADF1
The set state of 0 becomes unstable. That is, on the back side of the ADF 10, heavy objects such as the motors 32, 45, 96 are arranged, and the weight balance is considerably offset to the back side. Therefore, when the ADF 10 is closed, the moment acts on the rear side spacer 55 as a fulcrum in the direction in which the front side opens. In this case, when the copying machine main body 1 is opened and closed (particularly, clamshell type), the magnet 12 releases the attraction of the magnet 12 to the magnetic plate 4, and the front side of the ADF 10 slightly floats (FIG. 5B). (See), the balance will be lost in this state. Therefore, in this embodiment, the ADF 10
In order to reduce the load on the back side of the ADF 10, the back side of the ADF 10 is elastically hung with respect to the hinge stay 50. That is, the projecting piece 61 is fixed to the movable side metal fitting 5b holding the hinge stay 50, and the tension coil spring 63 (see FIGS. 4 and 5 (a) is formed between the projecting piece 61 and the projecting piece 62 provided on the frame 51R. )
Attached). The spring 63 elastically biases the back side of the ADF 10 upward with respect to the hinge stay 50, the weight balance of the ADF 10 is corrected, and the magnet 12 is disengaged from the magnetic plate 4 by shock and vibration, and the front side of the ADF 10 floats. It is possible to eliminate the trouble that occurs.

The lifting force of the spring 63 is generated by the ADF 10
The weight balance of the
It is necessary to consider so that 5 does not rise when the document passes. For the two hinge stays 50, the weight balance is different between the left and right sides (the right rear portion is relatively heavy), so it is preferable to change the lifting force between the left and right sides. As for the lifting force, the four spacers 54 and 55 are used for the platen glass 2.
Most preferably, it is adjusted so as to make uniform pressure contact. As described above, when the transport unit 40 is set on the platen glass 2 with a uniform weight, the transport belt 41 uniformly contacts the surface of the platen glass 2 and exhibits good document transportability.

The automatic document feeder according to the present invention is not limited to the above embodiment, but can be variously modified within the scope of the invention. In particular, the basic configuration of the ADF 10 is arbitrary, and for example, the paper feed unit 20 and the transport unit 4 can be used.
It may be configured such that 0 and 0 are divided, the transport unit 40 is hinge-supported, and can be opened to the copying machine main body 1.

[0019]

As is apparent from the above description, according to the present invention, the carrying section is held so as to be vertically movable with respect to the hinge stay, and the back side of the carrying section is elastically moved upward with respect to the hinge stay. The transport section is automatically positioned to follow the inclination of the platen glass, etc., and the weight balance, which was ubiquitous on the back side, has been corrected, and the ADF set state is stabilized, resulting in shock and vibration. Can solve the problem that the front side opens.

[Brief description of drawings]

The drawings show an embodiment of an automatic document feeder according to the present invention.

FIG. 1 is a schematic configuration diagram of an ADF.

FIG. 2 is a plan view showing an internal configuration of an ADF.

FIG. 3 is a perspective view showing a state where the ADF is lifted from the main body of the copying machine.

FIG. 4 is a perspective view showing a hinge mechanism portion of the ADF.

FIG. 5 is an explanatory diagram showing when the ADF is opened and closed.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Copier main body 2 ... Platen glass 5 ... Hinge metal fittings 10 ... ADF (automatic document feeder) 20 ... Paper feeding section 40 ... Conveying section 41 ... Conveying belt 50 ... Hinge stays 51F, 51R ... Frame 52, 53 ... Step Attached screw 63 ... Tension spring

Claims (1)

[Claims] 1. An automatic document feeder for sequentially transporting documents stacked on a tray to a fixed position on a platen glass of a copying machine, stopping them, and discharging them from the platen glass after image scanning is completed. The transport section having a carriage is held so as to be vertically movable with respect to a hinge stay that rotatably supports the apparatus main body at the back side of the copying machine body, and the back side of the transport section is elastically moved upward with respect to the hinge stay. An automatic document feeder characterized by being urged.