JPH0620973B2 - Paper detection device for copiers, etc. - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a sheet detection device in a copying machine or a printing machine.

As a paper detection device in a conventional copying machine or printing machine,
There is a "jam detection device" as described in JP-A-52-32707. As shown in FIG. 1, in this conventional device, a rotating roller 1 having a small inertia is attached to one end, and an intermediate portion of a swing lever 3 having a counterweight 2 attached to the other end is pivotally supported to rotate the rotating roller 1 in place. The rotation of the rotating roller 1 is caused by contacting and rotating on the sheet 5 conveyed on the table 4 by the optical sensor 6 installed on the rocking lever 3 and the rotation number detecting hole 7 formed on the rotating roller 1. By detecting, the information regarding the transfer state of the paper 5 is obtained.

However, in this conventional device, since the sensor 6 for detecting the rotation of the rotating roller 1 is installed on the swing lever 3 to which the rotating roller 1 is attached, the processing of the harness and the like is complicated, and The rotating operation of the rotating roller 1 is uncertain, which causes a detection error.

In addition to the above-mentioned conventional sheet detection devices, there is also a conventional sheet detection device that detects a sheet in a sheet stacking unit using a reflection type sensor. It is difficult to optically distinguish the inside paper from the incoming paper, and it has hardly been put to practical use.

Aim The present invention was made in order to eliminate the drawbacks of the above-mentioned conventional ones, and particularly in a copying machine or the like,
In a device that stores a sheet at a predetermined place after being conveyed, it is possible to reliably detect the entry of the sheet into the storage device.
Accordingly, it is possible to obtain accurate information regarding the transfer of the paper, and to provide a paper detection device that can be used as a paper jam detection and, if necessary, as a timing detection to a counter, a paper alignment device, or the like. It is intended.

Configuration The present invention will be described below based on the embodiments shown in the drawings.

FIG. 2 is a side view showing a schematic arrangement when the sheet detecting device 11 according to the present invention is used in an automatic double-sided mechanism of a copying machine.
The paper 5 that has been conveyed to the inside of 0 is conveyed inside the discharge gate device 100 by the feed belt 15 stretched between the driving roller 13 and the driven roller 14, and the discharge roller arranged inside this discharge gate device 100. By the operation of the gate claws 19 to 21 arranged between 16 to 18, the sheet is discharged onto the intermediate tray 22 from the position corresponding to the sheet size.
That is, the maximum size paper is as shown by arrow A in the figure.
The smallest size sheet is ejected as indicated by arrow B.

Each sheet 5 discharged onto the intermediate tray 22 is conveyed on the intermediate tray 22 by a feed roller 31 installed in the sheet aligning / refeeding section 200, and is shaken to the front part of the front end of the intermediate tray 22. It reaches a reference position where it abuts against the movable stopper 23. Paper 5
Are successively discharged onto the intermediate tray 22, and the front end of the paper 5 is accumulated at the reference position while being aligned by the stopper 23.

As shown in FIGS. 3 and 4, in the paper detection device 11, a drive shaft 32 is supported by a bracket 25 fixed to a body frame 24 of the copying machine, and the drive shaft 32 allows the base end of a feed roller support arm 33 to be supported. The part is pivotally supported. A feed roller 31 is rotatably attached to the tip of the feed roller support arm 33. The feed roller 31 is stretched between pulleys 34 and 35 coaxially attached to the feed roller 31 and the drive shaft 32, respectively. It is adapted to be driven by a drive belt 36. Further, the feed roller 31 is placed on the paper 5 accumulated on the intermediate tray 22, and the feed roller support arm 33 is pivoted by the bracket 25 so that the feed roller 31 is raised as the paper 5 is accumulated. .

At the lower end of the feed roller support arm 33, a detection roller support arm 37 is swingably attached at one end by a stepped screw 38 to one side surface of the feed roller support arm 33. The arm 33 is located at a position retracted from the tip of the arm 33. An arc-shaped guide hole 39 is formed at a position corresponding to an arc-shaped locus drawn by the tip portion when the detection roller support arm 37 of the feed roller support arm 33 is vertically swung from the horizontal state.
At the tip of the detection roller support arm 37, on the side opposite to the feed roller 31 with respect to the feed roller support arm 33,
A detection roller 41 is rotatably attached by a stepped screw 40 that is slidably fitted into the arc-shaped guide hole 31 from the feed roller 31 side and screwed into the detection roller support arm 37. A swing arm 42 is fixed to the detection roller 41 coaxially with the detection roller 41, and a pin 43 is projectingly provided at the tip of the swing arm 42.

Further, at a substantially middle position of the feed roller support arm 33,
The shaft 44 is fixed in a horizontal state, and a swing lever 45 is pivotally supported on the tip of the shaft 44 at approximately the middle portion thereof. One end 45a of the swing lever 45 extends to the measuring portion of the detection roller 41, and a guide hole 46 is formed along the longitudinal direction. The pin 43 of the swing arm 42 is inserted into the guide hole 46.
Is fitted, and the rocking lever 4 moves as the detection roller 41 rotates.
5 is rotated about a shaft 44.

The other end 45b of the swing lever 45 extends in the direction of the main body frame 24, and a plurality of slits 47 are provided at the other end.
Is provided.

A sensor 48 is mounted at a position facing the end of the swing lever 45 of the main body frame 24 where the slit 47 is provided. The sensor 48 is a so-called photo interrupter, and includes a light emitting unit and a light receiving unit. The light emitting unit and the light receiving unit are arranged so as to sandwich the other end of the swing lever 45. The sensor 48 is connected to an arithmetic unit (not shown), and as the rocking lever 45 is rocked, the slit 47 interrupts the light between the light emitting portion and the light receiving portion, thereby maintaining a constant value. An arithmetic unit (not shown) electrically counts how many times the sensor 48 is turned on and off within the time.

In the above embodiment, it is desirable that the feed roller 31 and the detection roller 41 are made of soft urethane foam, and at this time, F = N (μ _r −μ _p )> F _D ...... where F: feed roller paper feed Force F _D : Paper resistance received from detection roller N: Feed roller pressure μ _r : Friction coefficient between feed roller and paper μ _p : Friction coefficient between paper F <F _s …… F _s : Relationship between paper buckling resistance Need to meet.

In addition, the slit 47 when the paper 5 enters the stock
From FIGS. 5 and 6, the rotation speed θ when the sheet 5 moves the distance s from the contact point with the detection roller 41 to the stopper 23 is as shown in FIGS. , It is represented by. The length of the swing arm 45 is r, the distance between the rotation center of the detection roller 41 and the swing center of the swing lever 45 is c, the distance between the swing center of the swing lever 45 is l, and the swing lever is If the rotation angle of 45 is The relationship is established. Therefore, the speed v of the slit 47 is The slit 47 reciprocates between the light emitting portion and the light receiving portion of the sensor 48 at this speed v.

In the paper detection device, the paper 5 is discharged from the discharge gate device 100 onto the intermediate tray 22 (arrow c in FIG. 1 or 3).
Then, the sheet 5 is further moved forward by the rotation of the feed roller 31 and abuts against the stopper 23. At this time, the detection roller 41 also contacts the sheet 5 and is rotated as the sheet 5 is transferred. The rotation of the detection roller 41 is transmitted to the swing lever 45 via the pin 43 of the swing arm 42, and the swing lever 45 is rotated by a certain amount. The rotation amount of the swing lever 45, that is, the rotation amount of the detection roller 41 is detected by reading the movement of the slit 47 with the sensor 48.

If the sensor 48 does not detect a predetermined amount of rotation of the detection roller 41, the operator is warned by an appropriate means such as a buzzer or a display connected to the sensor 48. That is, when the detection roller 41 is not rotated by a predetermined amount, the paper 5 has a trouble such as a jam during the conveyance, and the trouble is detected by the sensor 48.

It should be noted that the feed roller 31 is lifted each time the paper 5 is deposited on the intermediate tray 22, and the feed roller support arm 33
Although the detection roller 41 is also lifted with the swing of the, the swing of the detection roller support arm 37 is allowed,
Since the detection roller 41 is always in contact with the paper by its own weight, the contact pressure of the detection roller 41 can always be kept constant irrespective of the amount of accumulated paper, and reliable paper detection can be performed.

Needless to say, the above-described paper detection device can be used not only for preventing troubles such as jams, but also for timing detection for a counter, a paper alignment device, and the like.

Needless to say, the above-described paper detection device can be used not only in a copying machine or a printing machine, but also in a device that temporarily stores conveyed paper in a predetermined place.

As described above, according to the present invention, the rotation amount of the detection roller which is rotated by being brought into contact with the conveyed sheet is rotated by connecting the detection roller with one end thereof. And the sensor attached to the body frame detect the paper conveyance state, so the sensor is easy to assemble and maintain, and the detection roller is a support arm near the downstream of the feed roller. The detection roller is rotated by the paper conveyed by the feed roller, which is arranged so that it can be swung freely, so the detection roller does not slip or skew, and the pressing force of the detection roller is reduced. It increases the rotatability to improve the paper detection accuracy, and the detection roller follows even if the stock amount increases, regardless of the stock amount. Those having various effects such as may indeed paper detection.

[Brief description of drawings]

FIG. 1 is a side view showing a conventional paper detection device, FIG. 2 is a schematic side view showing a case where the paper detection device according to the present invention is used in an intermediate stock portion of a double-sided automatic copying machine, and FIG. FIG. 4 is a side view showing an embodiment, FIG. 4 is a plan view of the embodiment, and FIGS. 5 and 6 are explanatory views for explaining sheet detection. 5 ... Paper, 24 ... Main body frame 31 ... Feed roller, 33 ... Feed roller support arm 41 ... Detection roller, 42 ... Swing arm 43 ... Pin, 45 ... Swing lever 47 ... Slit, 48 ...... Sensor

Claims (1)

[Claims] 1. A feed roller, which is attached to the other end of a support arm whose one end is pivotally supported by a main body frame and which conveys a conveyed sheet to a predetermined reference position, contacts the conveyed sheet. As described above, in the vicinity of the downstream of the feed roller, a detection roller that is swingably disposed on the support arm, and a detected portion that interlocks with the detection roller to detect the movement of the sheet by the rotation of the detection roller, A sheet detecting device in a copying machine or the like, characterized in that a sheet transfer state is detected by a sensor arranged on the main body frame facing the detected part and a calculating means for calculating a detection signal from the sensor. .