JP2610634B2 - Plate detection system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Purpose of the Invention] (Industrial application field) The present invention relates to an apparatus for detecting two sheets of a sheet material in a sheet material processing machine.

(Prior art) Conventionally, when supplying a sheet material to a sheet material processing machine such as a press,
The stacked plate materials are sucked by, for example, a vacuum pad or the like, and are supplied one by one to the processing machine side. However, when the plate material is thin or when rust-preventive oil is applied, two or more plate materials may be supplied to the processing machine in close contact with each other. Was injured.

Conventionally, in order to prevent such a so-called double-sheet picking, a non-contact sensor method using eddy current or a method of detecting a plate thickness by using a light-shielding plate that moves according to the plate thickness and a plurality of minute light receiving elements has been used. It has been adopted as a device.

(Problem to be Solved by the Invention) In the non-contact sensor system, when the material of the plate material is different,
Since the output of the sensor changes, it has to be adjusted each time, and it cannot be used when the plate material is nonmetallic. Also,
Adjustment was also required depending on the presence or absence of coating on the plate material surface. Further, it is necessary to keep the distance between the surface of the member and the sensor constant, and there is a problem that an error occurs when the distance changes due to a change in plate thickness.

In the method using a light-shielding plate and a plurality of minute light receiving elements, the current type has a maximum discrimination of 10 types of plate thicknesses. Knowing that, it was necessary to judge whether or not two sheets were taken from the measured thickness.

According to the above-mentioned method, it is possible to detect two sheets of a sheet material having 10 or more sheet thicknesses, but it is impossible to discriminate the sheet thicknesses of 0.9 mm and 1.0 mm because the discrimination types are small. It is. Therefore, usually, when a worker mistakenly flows a plate material with a thickness of 1.0 mm to a processing line where a plate material with a thickness of 0.9 mm flows, it will not be detected and will flow to the processing line unless two sheets are taken. become.

[Structure of the Invention] (Means for Solving the Problems) In view of the above-described conventional problems, the present invention relates to a method of mounting the plate material on a revolving plate that is rotatably provided at a position lateral to a pass line of the plate material. An upper arm and a lower arm that can be clamped from above and below are provided with a clamp provided so as to be rotatable in opposite directions around a coaxial center. The main body of the rotary encoder is provided on the one arm, and the output shaft is provided on the other arm. When the contact provided at the distal end of the upper and lower arms is fixed from the open end A to the closed position C where they are in contact with each other, the rotary encoder Z emits a Z pulse from the B to the closed position C. the initial value counting unit for counting the number of main pulse as an initial value P ₀ is provided, wherein the contact from the B position having issued the Z pulse is inserted a plate material between the contact child of primary pulses until it contacts the plate Before the count value P It is subtracted from the initial value P ₀ is made by providing an arithmetic unit for calculating a plate thickness of the plate material.

(Operation) The operation in the above configuration is as follows.

(A) The clamp is closed from the open end A position, the main pulse is counted from the B position where the Z-phase pulse as an auxiliary pulse of the rotary encoder is generated, the number of main pulses up to the clamp closed position C is obtained, and this is initialized. the value P _0.

(B) Next, at the position A of the clamp, a plate material is inserted between the surface contacts of the clamp, the clamp is closed, and the number of main pulses is counted from the position B where the seven-phase pulse is generated.

(C) Let P be the count value of the main pulse until both contacts come into contact with the plate.

(D) Calculate the plate thickness from the initial value P ₀ and the count value P and display it.

In this case, the A position, B position, and C position of the clamp are the open end, the position where the Z group pulse (auxiliary pulse generated once per rotation) of the rotary encoder is generated, and the open end, respectively, as shown in FIG. . Normally, the clamp is waiting at the A position.

 Next, a description will be given with reference to the flowchart of FIG.

By the procedure (a), the distance from the B position of the clamp to the C position, is converted into the main pulse number of the rotary encoder, which is the initial value P _0. This corresponds to step (1).

According to the procedure (b), when the plate is inserted between the two contacts and the clamp is closed, the main pulse is counted from the position B by the Z-phase pulse. This corresponds to step (2).

According to the procedure (c), the distance from the point B to the contact of the plate with the clamp is converted into the number of main pulses and becomes the count value P. This corresponds to steps (3) and (4).

According to the procedure (d), the difference between the initial value P ₀ and the count value P is obtained, and the difference is multiplied by a certain number to obtain the plate thickness, which is displayed on the display. This corresponds to steps (5) and (6).

(Example) Next, an example of the present invention will be described with reference to the drawings. As shown in FIG. 4, in the two-sheet detection device 1, the revolving plate 5 is provided on the fixed plate 3, and when the thickness of the plate material W is detected by the actuator 7, the path line of the plate material is indicated by an arrow. Turn 90 degrees to A detection device 9 is mounted on the revolving plate 5. The detection device 9 includes a clamp 15 including an upper arm 11 and a lower arm 13, a driving mechanism 17, a rotary encoder 19, and the like. The main body of the rotary encoder 19 is fixed to the upper arm 11 of the clamp, and its output shaft is fixed to the lower arm 13. Contacts 21 and 23 are attached to the tips of the upper and lower arms, respectively.

FIG. 3 shows an example of the measuring device. As shown in the figure, the A-phase and B-phase pulse signals of the rotary encoder 19 are quadrupled by a quadrupling circuit 25 in order to increase the resolution, and become one main pulse signal. This main pulse signal is sent to the parallel I / O port 27 together with the Z-phase signal. The Z-phase signal is adjusted in advance to be generated when the distance between the two contacts 21 and 23 of the clamp 15 is approximately 20 mm.

When the Z-phase pulse signal enters the parallel I / O port 27, this port provides a signal (E signal shown in the figure) that enables the main pulse signal to be input to the quadruple circuit 25 and a central processing unit (hereinafter referred to as CPU) 29. ) Is output for a certain period of time. That is, this Z-phase pulse signal is an interrupt signal to the CPU 29, and this signal
Causes the counter 31 to count the main pulse signals from the B position to the C position of the clamp.

In measuring the thickness, first, from the B position of the clamp, C
Count the number of main pulses P ₀ up to the position, and use this as the initial value.
It is stored in the RAM33. Next, the plate is inserted into the clamp, and the number of main pulses P from the position B until both contacts come into contact with the plate is counted. The CPU 29 calculates the difference between the initial values P ₀ and P,
The plate thickness is calculated by multiplying by a constant value (movement distance of both contacts per pulse), and this is displayed on the display 37. Initial value P ₀
May be measured once when the power is turned on.

[Effects of the Invention] As can be understood from the above description, since the present invention has the configuration described in the claims, it is possible to determine various types of plate thicknesses, and it is possible to detect double-sheet detection. It is possible.
Further, since the measurement is performed based on the Z-phase pulse, the measured value is not affected by the backlash of the mechanical system.

Therefore, adjustment corresponding to wear or the like after the completion of assembly of the detection device is not required, and maintenance-free, and measurement errors due to deterioration of the device are small. Further, according to this detection method, the measuring instrument can be reduced in size and cost can be reduced.

In addition, since the clamp having the upper arm and the lower arm is provided on a revolving plate that is rotatably provided at a position lateral to the path line of the plate material, it does not interfere with the path of the plate material, It is only necessary to turn when necessary.

[Brief description of the drawings]

FIG. 1 is a flow chart corresponding to the procedure of the present invention, FIG. 2 is an explanatory view of the position of a clamp, FIG. 3 is a block diagram showing an example of a measuring instrument used for carrying out the present invention, and FIG. It is a three-dimensional view of the sheet | seat material double-sheet detection apparatus which implement | achieved. DESCRIPTION OF SYMBOLS REPRESENTING PRIMARY PARTS OF THE DRAWINGS 1... Double-sheet detecting device, 11... Upper arm 13... Lower arm, 15... Clamp 19... Rotary encoder 21, 23. Processing unit, 31 ... Counter 37 ... Display

Claims (1)

(57) [Claims] 1. An upper arm (11) and a lower arm (11) capable of clamping the plate (W) from above and below on a revolving plate (5) that is rotatably provided at the side of the pass line of the plate (W). 13) is provided around the coaxial center so as to be rotatable in opposite directions, the main body of the rotary encoder (19) is provided on the one arm, and the output shaft thereof is fixed on the other arm, When closing the contacts (21, 23) provided at the distal ends of the upper and lower arms (11, 13) from the open end A position to the closed position C in contact with each other, the Z of the rotary encoder (19) is closed.
An initial value counting unit that counts the number of main pulses from the position B that issued the pulse to the closed position C as an initial value (P ₀ );
Inserting a plate (W) between the contacts (21, 23)
The count value (P) of the main pulse from the position B at which the pulse was issued until the contactor (21, 23) contacts the plate (W) is subtracted from the initial value (P ₀ ) to obtain the plate (W). An apparatus for detecting two sheets of sheet material, comprising a calculating part for calculating the sheet thickness.