JPS58187223A - Automatic die height adjusting device of press - Google Patents

Abstract

PURPOSE:To obtain a titled automatic adjusting device which is capable of setting the die height with high accuracy, by automatically stopping a slide adjusting motor when a load value converted from detecting pressure of an oil pressure chamber of a slide for constituting a part of an overload safety device, etc. of a press reaches an optional set value set in advance. CONSTITUTION:When adjusting the die height, a metallic die is carried into a press in the way as a conventional case, and after that, a slide is made to descend by starting a slide adjusting motor 26. As the slide descends, it contacts with a punch, but its descent is maintained continuously thereafter. Therefore, a load increases, pressure of an oil pressure chamber 1 rises, and a display load of an display 17 increases gradually. Subsequently, when this load reaches a set value of a digital setting device 20, an output of a comparator 21 becomes on, and a relay 23 is driven through a relay driver 22. Accordingly, a stop signal is supplied to the motor 26 and the slide is stopped. Also, after the slide stops, the punch is clamped, and the slide is then returned to the top dead center, by which the die height adjustment is finished.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an automatic die-hide adjustment device for a press.

To set the die-hide using the slide adjustment device equipped on the press, it is necessary to apply a preload between the upper and lower molds.

For this purpose, various types of die-hyde automatic adjustment devices have been proposed and put into practical use.

None of them could be said to be sufficient.

In view of these circumstances, the present invention detects the pressure in the hydraulic chamber of the slide that constitutes a part of the overload safety device or load cell of the press, and converts the load value from this pressure into an arbitrary preset value. To provide an automatic die-hide adjusting device which can set a die-hide with high precision by stopping a slide adjusting motor in force when a set value is reached to give a desired preload.

The present invention will be explained in detail below based on an illustrated embodiment.

FIG. 1 is an electric circuit diagram showing an embodiment of the present invention. A hydraulic chamber 1 constituting a part of a hydraulic overload prevention device is formed in the sliding part of the press, and this hydraulic chamber 1 has a constant pressure. pump 2
Pressure oil is supplied at a predetermined pressure.

The pressure sensor 3 to which the pressure of the hydraulic chamber 1 is applied is.

Outputs a voltage proportional to the pressure in the hydraulic chamber 1, and this voltage is
After being amplified by the amplifier 4, it is supplied to the addition side input terminal of the adder/subtractor IO. Further, the output of the amplifier 4 is also supplied as the manual power of the analog switch 8.

This analog switch 8, 2-inverting amplifier 9° capacitor C constitutes a sample and hold circuit.

Pressure in hydraulic chamber 1 immediately before press load is generated.

The output voltage ph of the amplifier 4 is sampled and held to obtain a voltage pc corresponding to the preload of the hydraulic chamber 1. That is, as shown in FIG. 2, the output of the rotary cam switch 5, which is turned ON in the press load generation region, is supplied to the transistor 7 via the inverter gate 6, and the output of this transistor 7 is supplied to the analog switch 8 via the diode D. By supplying it as a control input, the crank angle of the press reaches the load generation angle and the rotary cam switch 5
The analog switch 8 is turned on only until it is turned on. Then, when the load generation angle is reached and the rotary cam switch 5 is turned on.

When the analog switch 8 is turned off, the voltage ph outputted from the amplifier 4 immediately before turning off is sampled to obtain the voltage pc corresponding to the prepressure value of the hydraulic chamber 1.

On the other hand, the preload equivalent voltage pc obtained as above is
It is supplied to the subtraction side input terminal of the adder/subtractor 10. still,
Since the constant 1/K is given to this adder/subtracter 10 by the variable resistor 11 for gain adjustment, the output of the adder/subtracter 10 becomes .

Further, the output of the adder/subtractor IO is supplied to a function generator 12 to perform a square root calculation. That is, the pressure in the hydraulic chamber 1 is Ph,
If the preload of the hydraulic chamber 1 is PC2 and the constant is K, then the press load P is.

is given by When the calculated value using this formula and the actual value were compared, they matched to a degree that would not cause any practical problems, so it can be said that the output light of the adder/subtractor 10 is an analog signal.

The analog signal (press load signal) is supplied to the peak hold circuit 13 and held at its peak.
The hold value (maximum load value) of 3 is converted into a digital signal by the A-D converter 14 and stored in the latch circuit 15. The reset signal of the peak hold circuit 13 is supplied when the timing circuit 19 detects through the gate 18 that the rotary cam switch 5 is turned on, and the latch circuit 15 is supplied with the timing signal output from the timing circuit 19. I try to remember it. Therefore, since the peak value held in the peak hold circuit 13 is stored and held in the latch circuit 15, the maximum value continues to be held even if the peak hold circuit 13 is attenuated due to changes over time.

As described above, the output of the latch circuit 15 that stores the output of the peak hold circuit 13 is supplied to the display 17 via the 9-display driver circuit 16, which numerically displays the maximum load up to that point. At the same time, the output of the latch circuit 15 is also supplied to a comparator 21 to which the output of the digital setting device is supplied as a reference value, and when the output of the latch circuit 15 becomes larger than the set value by the setting device, the relay driver 21
Relay 23 is driven 1 via 2, and 21 is actuated to contact the relay to suddenly stop a slide adjustment motor (not shown), thereby preventing the slide from descending.

Also, the output of the latch circuit 15 is as follows.

The load data is also supplied to other equipment B, and can be used as data for mold protection and monitoring of variations in supplied materials, and data for load analysis using a computer or the like. still.

The latch circuit 15 is reset when a timing signal is supplied to the primary cycle.
It may be reset when the angle reaches 0°. Furthermore, the comparator 21.

In principle, it works only when adjusting the die-hide, but since the power to the slide adjustment motor is turned off when the die-hide is not being adjusted, there will be no particular inconvenience if it is operated all the time.

In the above configuration, when adjusting the gain/eight, the mold is carried into the press as in the conventional method, and then the slide adjustment motor is started to lower the slide. The slide comes into contact with the toe shape as it descends, but continues to descend thereafter. Then, the load increases and the pressure in the hydraulic chamber 1 rises, so the load displayed on the 2-indicator 17 gradually increases. When this load reaches the set value of the digital setting device, the output of the comparator 21 turns ON and relay B is driven via the relay driver 22, so a stop signal is supplied to the slide adjustment motor and the slide is adjusted. Stop. After the slide has stopped in this manner, the upper die is clamped, and the slide is then returned to the top dead center to complete the die adjustment.

As shown in FIG. 3, the slide adjustment device includes a slide adjustment motor 26, a worm n driven by the motor 26, and a worm gear that rotates integrally with an adjustment screw 29 screwed into the connecting rod path. The adjustment screw can be configured to expand and contract relative to the connecting rod path by the rotation of the slide adjustment motor 3. 31 is a crankshaft, and 32 is a slide.

As explained above, according to the present invention, the slide adjustment device operates to lower the slide and apply a preload until the load value set with a digital setting device is reached.
Die-hide can be adjusted automatically. In addition, since the preload value can be changed arbitrarily, the mechanical properties of the workpiece material and

It is possible to easily obtain the optimum die-hide according to the characteristics of the mold, etc.

[Brief explanation of the drawing]

FIG. 1 is an electric circuit diagram of an embodiment of the present invention, FIG. 2 is an operation timing diagram of a rotary cam switch, and FIG. 3 is a sectional view of a slide adjustment device. ■...Hydraulic chamber 22...Relay driver 3...Pressure sensor device...Relay 15...Latch circuit row...Relay contact addition...Digital setting device 26...Slide adjustment motor 21 ... Comparator patent Applicant: AIDA Engineering Co., Ltd. Representative Patent Attorney Kiyoshi Nakayama (and one other person)

Claims (1)

[Claims] (1) A pressure sensor that detects the pressure in the hydraulic chamber provided in the sliding part, a means for calculating the load of the press based on the output of the sensor, and a means for calculating the load of the press based on the output of the sensor, and a means for calculating the load of the press when the calculated load value reaches an arbitrary preset value. An automatic die-hide adjustment device for a press, comprising means for stopping a slide adjustment motor when the slide adjustment motor is stopped.