JPS6021837B2 - How to control the interlocking timing between press machines and other machines - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention controls the operation of a press machine by constantly monitoring the operating state of a punch in a press machine in terms of its position and speed. It is designed to control the timing of interlocking with the machine.

[Description of prior art]

Conventionally, most of the control of press machines has been related to the stop positioning of the punch's top dead center, so for example, the operation timing of the robot that takes out the molded product and the transport mechanism that moves with the robot that takes out the molded product. In this method, the punch position is detected and a synchronization signal is obtained using a mitt switch, etc., and if there is a deviation in the timing of positioning the top dead center of the punch or the speed of the punch changes, There was a problem that it could not be used as an appropriate synchronization signal.

In addition, since the conventional control method for press machines is related to the stop position of the punch at the top dead center as described above, even if the punch operates in an inconvenient position other than the top dead center, As long as this inconvenient product does not appear as a shift in the top dead center stop position of the punch, the press machine itself cannot automatically detect the inconvenient operation and avoid the above inconvenience, so the press machine cannot be moved. There is a problem in that it is not possible to notify other machines that operate the machine of the above-mentioned inconvenience, and the other machines must take measures to detect the above-mentioned inconvenience on their own.

0 [Object of the Invention] In view of the insufficiency of the conventional press machine control method as described above, the present invention has an extremely simple configuration to accurately control the operation of the punch of a press machine in terms of its position and moving speed. The purpose of this invention is to provide a method that can control the machine and also control other machines in conjunction with each other in a more timely manner.

[Structure of the invention]

The present invention, which can achieve the above objects, detects the punch position of a press machine using a pulse signal, and detects the moving speed of the punch by making the pulse signal correspond to a time pulse. A speed control signal is given to a drive source so that when the punch reaches a predetermined position, a timing signal is outputted to notify other machines of the same. The speed control signal is received together with the timing signal, and the predetermined time from receiving the timing signal until the next linked operation is corrected by the speed control signal to link with the punching operation of the press machine. This is a method of controlling interlocking timing between a press Z-space machine and other machines, which is characterized by the following.

[Explanation of Examples]

Next, the method of the present invention will be explained with reference to the drawings as an example of control when a crank press is combined with a robot for supplying material.

First, the method of controlling the crank press will be explained.

1 is a crankshaft, 2 is an upper end connected to the crankshaft 1,
A connecting rod is equipped with a slide including a punch 3 at its lower end, 4 is a bolster including a die placed on the pet in alignment with the bottom second dead center of the punch 3, and 5 is a connecting rod with a slide including a punch 3; The flywheel 6 attached to the crank frame 1 is a drive source that applies rotational force to the crank frame 1. Here, the flywheel 6 is connected to the crank frame 1 via a deceleration mechanism 7, a clutch 8, and a brake 9.
A similar electric motor is used, and the above-mentioned members are arranged on a frame to form the basic structure of a crank press.

10 is a slit disk 10a attached to the crankshaft 1.
This embodiment is an encoder consisting of a light emitting section 10b and a light receiving section 10c which are arranged opposite to each other with the disc 10a in between, and a pulse output section 10d which receives a signal from the light receiving section 10c and outputs a pulse signal. Here, two types of pulse signals are output, representing a rotation angle signal A of 100 pulses per one rotation of the crankshaft 1 and a four-rotation speed signal AI of 1 pulse per one rotation of the crankshaft 1.

Reference numeral 11 denotes a control section that controls the operation of the clutch 8, brake 9, and drive source 6.

This control section 11 consists of a punch position control section 11A and a punch speed control section 11B.

The punch position control unit 11A controls the operation timing of the clutch 8 and/or the brake 9, and
a position command circuit 12 that commands the rotation angle and rotation speed of the crankshaft 1 per stroke; and this command circuit 1.
The command value of the control position (punch position = crank angle) from 2 is converted into a pulse signal amount A' or A,' of the same unit as the signal representing the rotation angle pulse and rotation speed pulse of the encoder 10 and stored. a position calculation unit that receives a pulse signal A or A supplied from the encoder 10 and subtracts it from the command value pulse signal A' or A,' to form a position control signal for operating the clutch or brake in a timely manner; 13, obtains the output of the position control signal of the calculation section 13, and also obtains a command speed signal from the speed calculation section 16, which will be described later, via the line L, corrects the control signal, and operates the clutch 8 or the control signal at a more appropriate timing. and a position control section 14 that operates the brake 9.

This correction is performed in such a way that, if the position control signal is a signal for operating the brake at point P, a command speed signal that takes into account the current speed is obtained and correction is made to point P'.

In order to control the drive source 6, the punch speed control section 11B has the following functions:
A speed setting circuit 15 that outputs the speed set for each section, in which a section speed is set at multiple points including the top dead center of the punch 3 during one stroke, and a rotation supplied from the encoder 10. A pulse signal of the actual speed of A/B is formed by making the angular signal A correspond to the clock pulse B supplied from the reference clock 17, and this is subtracted from the section speed from the setting circuit 15, and the difference is set to zero. It consists of a speed calculation section 16 that outputs a speed control signal so that the speed control signal is outputted, and a drive source control section 18 that controls the drive source 6 using the speed control signal from the calculation section 16. By the action of the control section 11, the operating positions of the clutch 8 and the brake 9 are controlled according to each layer of the punch 3 (according to the rotation angle of the crankshaft 1), and the speed of the punch 3 (according to the rotation angle of the crankshaft 1) is controlled. 1 rotational speed) is controlled, approximately clutch 8 or brake 9
Not only is there no risk of a shift in the operating timing of the punch 3, but also the speed of the punch 3 is constantly controlled, making it possible, for example, to maintain the cycle of the punch 3 at a predetermined constant cycle. By the way, when press forming is carried out continuously, due to the supply V supply and take-out timing of the workpiece,
The cycle of one stroke of the punch 3 must be as constant as possible, but if the timing of the brake operation is off for some reason, the time it takes for the punch 3 to reach from the top dead center to the bottom dead center may vary, or the press The speed of the punch 3 during molding may fluctuate, which may cause operational inconvenience. However, according to the above-mentioned press machine, even if the brake timing is off, the output of the drive source 6 is controlled so that the speed of the slide 3 is at a predetermined speed, so that the output of the drive source 6 is controlled until the punch 3 reaches the bottom dead center. This makes it possible to immediately restore the predetermined state from fluctuations in time and fluctuations in the speed of the slide 3 near the bottom dead center. Next, in the press machine having the above-mentioned structure, how to establish interlock timing when moving another machine, such as a work robot for taking out a workpiece, from this press machine will be explained.

Now, the rotation speed of the crankshaft 1 is supplied to the position calculation unit 13 as a pulse signal A as the punch 3 moves up and down, so basically, the rotation speed of the crankshaft 1 is determined from the top dead center of the punch 3 via the line -. The position control signal can be used as a work timing signal for the work robot.

In other words, when the punch 3 moves from the top dead center to the bottom dead center, performs a predetermined process, and then moves toward the double top dead center, for example, the punch 3
A predetermined timing signal is output from the line L2 at the bottom dead center position of the line L2, and this timing signal is given to the working robot. for example,
It is possible to perform the extraction work.

Here, the reason why we did not output the take-out position itself but output it at the bottom dead center of the punch 3, which is a little earlier, was in anticipation of a delay in the operation of the work robot, and the work robot Therefore, it is sufficient to carry out the extraction work after a predetermined time Δt, taking into account the delay in the operation of the working robot. If you look at it differently, the above line L2
It is thought that the timing signal corresponding to the position of the punch 3 (corresponding to the rotation angle of the crankshaft 1) obtained through the above function has substantially the same effect as a timing signal from a conventional limit switch or the like. However, the following inconvenience occurs with only the timing signal obtained from the line L2.

That is, in the above example, when the punch 3 reaches the bottom dead center position,
This is a case where, after outputting a predetermined timing via the line, the punch 3 engages with the workpiece and the speed of the punch 3 changes more than expected.

In this case, since the work robot does not know the change in the speed of the punch 3, it will perform the extraction operation after a predetermined time Δt, and may fail to grasp the workpiece or come into contact with the punch 3 due to incorrect extraction timing. Otherwise, the timing of taking out the punch 3 may be too late, which may interfere with the processing operation of the next punch 3. Therefore, in the method of the present invention, the speed signal outputted from the speed calculating section 16 is taken out from the line L3 to make it possible to respond to changes in the speed of the punch 3.

To give an example, assume that in the above example, a timing signal is output from the position calculation section 13 at the bottom dead center of the punch 3 via the line L2.

The working robot first receives this timing signal and also receives a speed control signal via the lines, and uses both signals to form a predetermined time Δt. In this case, the formation of the predetermined time Δt is performed as follows. '■ Assuming that the standard speed at the bottom dead center of the punch 3 (actually the rotational angular velocity of the crankshaft 1) is Vo, the predetermined time under the standard speed Vo is △to, the control speed is V, and △t - △ et al.
(V.

/V) is the simplest example, but in calculating this predetermined time Δt, the speed of the punch 3 and the crankshaft 1
Of course, it is possible to calculate more accurately by creating a relational expression for the rotational speed.

(2) It is also possible, of course, to calculate the speed change rate V/Vo and use it as a control signal for stopping the system if this value is greater than a predetermined value. The above explanation of the interlocking timing has been made with respect to the work of taking out the workpiece, but the interlocking timing of material supply and other operations can also be explained in the same way.

In the above embodiments, a crank press has been described, but it goes without saying that the method of the present invention can be applied to any type of press machine in which the punch is stroked by an appropriate drive source.

〔Effect of the invention〕

The present invention is as follows: Since the punching operation of the press machine is constantly monitored in terms of its position and speed, and the timing of the press machine and the machines linked thereto is controlled, the press machine can always be controlled in an optimal state. As well,
The signals generated for this control can also be used to control related equipment linked to this press machine, producing effects that could not be obtained with conventional press machine control methods.

[Brief explanation of drawings]

The figure is a control block diagram showing an example of a press machine using the method of the present invention. 3... Punch, 6... Drive source, 8... Clutch, 9...
Brake, 10...Encoder, 11...Control unit, 11A...Punch position control unit, 11B...
Punch speed control section, 2...Position control signal extraction line,
L...Speed control signal extraction line.

Claims (1)

[Claims] 1. The punch position of the press machine is detected by a pulse signal, the pulse signal is made to correspond to a time pulse to detect the moving speed of the punch, and a speed control signal is applied to a drive source of the punch to control the punch. is controlled at a predetermined speed, and when the punch reaches a predetermined position, a timing signal is output to notify other machines of the same.Meanwhile, in other machines linked to the press machine, the The speed control signal is received along with the timing signal, and a predetermined time from receiving the timing signal to starting the next linked operation is corrected by the speed control signal to link with the punching action of the press machine. A method for controlling interlocking timing between a press machine and other machines, characterized in that: