JPH037113B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a document conveying device in a facsimile machine, an electrophotographic copying machine, or the like.

In facsimile machines and the like, in order to read a document, the document is conveyed by document conveyance rollers arranged on both sides of a target glass. The image of the moving document is read photoelectrically on a target glass and converted into an electrical signal. If the leading edge of the document is bent or curved, the document may get stuck during transportation.
This is usually called jiam. In order to remove a jammed document, it is first necessary to disengage the feed roller and pressure roller of the document transport roller holding the jammed document, and to create a space between them. Thereby, the jammed original can be easily taken out. On the other hand, some document conveyance devices include a pressure plate for bringing the document into close contact with a contact glass. In such an apparatus, by opening the pressure plate, the original can be easily taken out even if the original does not come out of the apparatus and is completely jammed inside the apparatus. In the conventional document conveyance device, the pressure on the conveyance roller is first released and then the pressure plate is released as necessary, which requires two operations and is cumbersome to operate.

SUMMARY OF THE INVENTION An object of the present invention is to provide a document conveyance device that can release the pressure on the conveyance roller and open the pressure plate in one operation in order to facilitate the removal of jammed documents.

Hereinafter, the present invention will be explained with reference to the accompanying drawings. FIG. 1 schematically shows an example of a document conveying device according to the present invention. On both sides of the target glass 11, feed rollers 17, 18 and a pair of pressure rollers 19, 20 that are in normal pressure contact with these are provided via guide plates 13, 14 and 15, 16 for guiding the original 12. Document transport rollers 21 and 22 are arranged. The original 1 is placed on the target glass 11.
2 on the target glass 11 is arranged, and this is attached to the arm 24 with the screw 2.
5, the arm 24 is attached to the shaft 2
It is fixed to 6. As shown in FIG. 2, the shaft 26 is rotatably supported by a side plate 27 of the device, and has a rotating cam 28 fixed to its end.
The opposite end of shaft 26 has the same configuration. This rotary cam 28 is formed into a D shape by cutting out a part of the peripheral surface of a disc, but it may also be an eccentric cam, and the flat part of the D shape normally faces upward. It is fixed to the shaft 26.
The feed rollers 17 and 18 are rotatably supported by the side plate 27 and receive power transmitted from the outside, but the pressure rollers 19 and 20 are rotatably supported by the side plate 27.
7, and support levers 29 and 30 are fixed to the ends of the rotating shaft. The support levers 29 and 30 are connected to the side plate 2 by pins 31 and 32.
7, and as shown in FIG. 3, their rising tops are connected to each other by a tension coil spring 33, and each pressure roller 19, 20 is connected to a feed roller. 17 and 18 are pressed against each other. On the other hand, one end of the flat part of the rotating cam 28 is attached to the side plate 27 with a pin 3.
The other end of a release lever 35 rotatably supported by 4 is in contact with the release lever 35 . Release lever 35
has a bent portion 35a at the lower center thereof, and support levers 29, 3 are mounted on the bent portion 35a.
0's front legs 29a and 30a are on it. Therefore, the release lever 35 and the support levers 29, 30
A link mechanism is formed.

Returning to FIG. 1, the document 12 inserted between the guide plates 13 and 14 is conveyed while being held between the feed roller 17 and the pressure roller 19 of the conveyance roller 21. When the original 12 passes over the target glass 11, the image of the original 12 is illuminated by the lamp 36, the reflected light is reflected by the mirror 37, and condensed by the lens 38 to be displayed on the CCD. An image is formed on the image sensor 39, and the document is read. This is a facsimile reader,
In the case of an electrophotographic copying machine, the reflected light from the original is
The light is irradiated through an imaging lens onto a photoreceptor that moves in synchronization with the original.

When the document 12 being conveyed jams midway, the driving of the conveyance rollers 21 and 22 is first stopped, the arm 24 is lifted, and the pressure plate 23 is rotated about 90 degrees around the shaft 26. This results in
The rotating cam 28 also rotates approximately 90 degrees, so the fourth
As shown in the figure, the rotating cam 28 pushes up the release lever 35. As a result, the release lever 35 swings upward around the pin 34, and its bent portion 35a also moves upward, so that the support lever 29, which was riding on it,
30's front legs 29a, 30a are also lifted upward, and each support lever 29, 30 swings around pins 31, 32 to move the respective pressure rollers 19, 20 away from the feed rollers 17, 18. become. In this way, with one action, the top of the target glass is opened, the pressure on the conveying roller is released, and the jammed document can be easily taken out.

The pressure plate 23 rotates around the shaft 26, and due to its own weight, the original 12 on the target glass 11 is moved.
However, as the thickness of the document 12 increases, the target glass 1
1, the original 12 cannot be evenly brought into close contact with the target glass 11 as a whole. Therefore, the pressure plate 23 and the shaft 26
The pressure plate 23
Since the sheet can follow the surface of the target glass 11, even thick originals can be pressed uniformly onto the target glass 11. In the embodiment shown in FIG. 1, this "floating fixation" can be achieved by making the fitting part between the arm 24 and the shaft 26 oval shaped with different sizes as shown in FIG. Can be done. This "floating fixation" only requires that the arm 24 can move at least in the vertical direction relative to the fixed shaft 26, as shown in the figure. The key is to mount the pressure plate so that there is some play in the vertical direction, that is, in the thickness direction of the document, and the pressure plate and shaft rotate together.

Although this invention has been described above with reference to the specific embodiments shown in the drawings, this invention can be modified in various ways using known techniques, and the spirit and scope of this invention as set forth in the claims may vary. All modifications within are intended to be included within the scope of this invention.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram showing an example of a document conveying device according to the present invention, FIG. 2 is a partial schematic plan view of the device shown in FIG. 1 excluding the feed roller, and FIGS. 3 and 4 are FIG. 5 is an explanatory diagram showing the operation of the link mechanism of the apparatus shown in FIG. 1, and FIG. 5 is a schematic diagram showing an example of the connection between the pressure plate and the shaft in the document conveying apparatus of the present invention. 11...Target glass, 12...Original, 1
7,18...Feed roller, 19,20...
Pressure roller, 21, 22...Document transport roller, 23...Press plate, 26...Shaft, 2
8... Rotating cam, 29, 30... Support lever, 3
5...Release lever, 36...Lamp, 37...
...mirror, 38...lens, 39...image sensor.

Claims (1)

[Scope of Claims] 1. A document transport roller consisting of a pair of a feed roller and a pressure roller arranged on both sides of the target glass; a pressure plate for pressing the document disposed on the target glass; a shaft fixed to one side and having a rotating cam at its end; and a link mechanism that engages with the rotating cam and swings a support lever that supports the pressure roller; By operating the pressure plate in the direction of opening using the shaft as a rotational fulcrum, the rotary cam is rotated and the support lever is swung, thereby separating the pressure roller from the feed roller. At the start of the opening operation of the pressure plate, the rotary cam releases pressure contact between the pressure roller and the feed roller and begins to separate them, and during the opening operation of the pressure plate, the pressure roller and feed roller are separated. 1. A document conveying device characterized in that a separation operation between the feed roller and the feed roller is stopped, and the separation position is maintained until the pressure plate is completely released. 2. The document conveying device according to claim 1, wherein the pressure plate and the shaft are loosely coupled.