JPH08174097A - Hydraulic circuit of hydraulic turret punch press - Google Patents

Abstract

PURPOSE: To enhance the responsibility of a hydraulic pump and improve the productivity by using an inclining plate system variable capacity hydraulic pump as the hydraulic source, installing a control circuit composed of another hydraulic pump, servo and servo cylinder for controlling the capacity, and attaching a fly wheel on a driving shaft of the variable capacity hydraulic pump. CONSTITUTION: An inclining plate system variable capacity hydraulic pump 1 is driven with a driving motor 5 through a fly wheel 3 and a belt 9 attached on the driving shaft. The control of the capacity of this hydraulic pump 1 is executed by changing the inclining angle of the inclining plate, the hydraulic fluid for that purpose is pumped up from a tank T with a hydraulic pump 11, it is sent to a servo cylinder 15 with a comparatively small electromagnetic switching valve 13, and the inclining angle of the hydraulic pump 1 is changed by rotating an operating bar 19 right and left through a piston rod 17. Further, after the hydraulic fluid from the hydraulic pump 1 is accumulated partially in an accumulator 23, it is sent to a hydraulic cylinder 123 with the control of the electromagnetic switching valve 25.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to improvement of a hydraulic circuit of a hydraulic turret punch press.

[0002]

2. Description of the Related Art FIG. 2 is a schematic view of a hydraulic turret punch press. As shown, the hydraulic turret punch press 101 includes a lower frame 103 and a left column 1.
05, the right column 107, and the upper frame 109 are formed in a box shape, and a shaft 111 provided on the lower frame 103.
A lower turret 115 having a plurality of dies 113 is attached to the shaft 117 provided on the upper frame 109.
And an upper turret 121 having a plurality of punches 119.
(Rotating in synchronization with the lower turret 115) is attached. Above the punch 119, the hydraulic cylinder 12
3, the striker 125 is provided on the upper frame 9, and the hydraulic cylinder 123 is connected to a hydraulic circuit described later.

A clamp 127 for gripping the work W is attached to a carriage 129, and the carriage 129 moves inside the carriage base 131 by means of a ball screw device 133, a guide rail 135, an X-axis motor (not shown), and the like (perpendicular to the paper surface). Direction) freely move. In addition, the carriage base 131 includes a nut member 137 and a ball screw device 1.
It is freely movable in the Y-axis direction (left-right direction on the paper surface) by the 39, Y-axis motor 141 and the like. Therefore, the work W is gripped by the clamp 127, and is moved by NC control so that the processing position is between the punch 119 and the die 113, and the hydraulic cylinder 123 performs a predetermined punching process.

FIG. 3 shows a conventional hydraulic circuit. As shown in the figure, the hydraulic oil in the oil tank T is sucked up by the swash plate type variable displacement hydraulic pump 145 through the filter F and the check valve C, is compressed, and is regulated by the relief valve 147 up to the maximum pressure. Ascend, solenoid directional switching proportional valve 1
It is sent to the P port of 51 and is sent from the A and B ports to the hydraulic cylinder 123 by the control of the valve. Hydraulic cylinder 1
The return oil 23 is returned to the oil tank T from the R port. A part of the pressure oil discharged from the hydraulic pump 145 is stored in the accumulator 149. In addition, a cylinder type accumulator 153 that absorbs pulsation is provided in the return oil piping to the oil tank T.
Is installed.

When the discharge pressure is low, the swash plate type variable displacement hydraulic pump 145 increases the inclination angle of the swash plate to increase the discharge amount, and when the discharge pressure is high, the inclination angle is decreased to decrease the discharge amount. It automatically operates so that the discharge pressure becomes the maximum pressure regulated by the relief valve 147.

As described above, in the hydraulic circuit of the conventional hydraulic turret punch press, in order to increase the productivity as high as that of the mechanical turret punch press, a large-capacity hydraulic pump and a large electromagnetic directional switching proportional pump are provided. A method of providing a valve and supplying pressure oil to a hydraulic cylinder has been adopted.

[0007]

As described above, in the hydraulic circuit of the conventional hydraulic turret punch press, since a large capacity swash plate type variable capacity hydraulic pump is driven, a large drive motor is required, and a large capacity is required. In order to control the direction and flow rate of the pressure oil, a large capacity electromagnetic directional switching proportional valve was used. Further, since the discharge amount control of the hydraulic pump is performed by the discharge pressure of the hydraulic pump as described above, it is difficult to control the flow rate of the pressure oil to the hydraulic cylinder with high response by controlling the electromagnetic directional switching proportional valve. Atsuta

The present invention has been made in view of such a problem. By controlling the flow rate of the hydraulic pump and the direction switching of the pressure oil by separate control valves, it is possible to perform control with a higher response than before. It is also possible to provide a hydraulic circuit for a hydraulic turret punch press that is highly productive and energy-saving, by enabling a large-capacity hydraulic pump to be driven by a motor that has a relatively smaller capacity than before. To aim.

[0009]

In order to achieve the above object, the present invention provides a swash plate type variable displacement hydraulic pump as a hydraulic source in a hydraulic circuit of a hydraulic turret punch press, and separates its displacement control. A control circuit consisting of a hydraulic pump, a servo valve and a servo cylinder is provided, and a flywheel is attached to the drive shaft of the swash plate type variable displacement hydraulic pump,
An electromagnetic directional control valve is used to switch the direction of the pressure oil of the hydraulic cylinder.

[0010]

With this configuration, the displacement of the swash plate type variable displacement hydraulic pump can be controlled with high response by the control circuit, and the inclination angle of the swash plate is minimized (zero) when the hydraulic cylinder is at rest. ), The pump motor is driven to store energy in the flywheel,
The hydraulic pump can be driven by a motor having a comparatively small capacity as compared with the prior art by releasing the hydraulic cylinder during operation.

[0011]

Embodiments of the present invention will now be described with reference to the drawings. FIG. 1 is an explanatory diagram of an embodiment of a hydraulic circuit of the present invention. As shown in the figure, the swash plate type variable displacement hydraulic pump 1 includes a flywheel 3 attached to its drive shaft,
It is driven by a belt 9 provided between pulleys 7 attached to the shaft of the drive motor 5.

To control the displacement of the swash plate type variable displacement hydraulic pump 1, the inclination angle of the swash plate is changed by a control circuit consisting of the hydraulic pump 11, the servo valve 13 and the servo cylinder 15, the piston rod 17, the operating rod 19 and the like. Is done by doing. The hydraulic oil is supplied to an oil tank T by a hydraulic pump 11 (capacity is much smaller than that of the swash plate type variable displacement hydraulic pump 1).
Is sucked up through the filter F and the check valve C, and is sent to the P port of the relatively small electromagnetic directional switching proportional valve (servo valve) 13. By the control of this valve, pressure oil is supplied from the A and B ports to the servo cylinder 15 And the operating rod 19 is rotated left and right via the piston rod 17 to control the tilt angle of the swash plate of the swash plate type variable displacement hydraulic pump 1.

The maximum pressure of the pressure oil discharged from the swash plate type variable displacement hydraulic pump 1 is regulated by the relief valve 21,
Part of it is accumulated in the accumulator 23 and then sent to the P port of the electromagnetic directional control valve 25, and the pressure oil is sent from the A and B ports to the hydraulic cylinder 123 by the control of this valve.

[0014]

As can be understood from the above description, since the present invention has the configuration described in the claims, it is possible to control the displacement of the variable displacement hydraulic pump with high response. The productivity can be improved, and since the variable displacement hydraulic pump is driven by a small displacement motor, power can be saved. Further, since the displacement of the variable displacement hydraulic pump is controlled by a relatively small electromagnetic directional switching proportional valve, the manufacturing cost can be reduced.

[Brief description of drawings]

FIG. 1 is an explanatory diagram of an embodiment of a hydraulic circuit of a hydraulic turret punch press of the present invention.

FIG. 2 is an explanatory diagram of a hydraulic turret punch press.

FIG. 3 is an explanatory diagram of a conventional hydraulic circuit of a hydraulic turret punch press.

[Explanation of symbols]

 1 Swash plate type variable displacement hydraulic pump 3 Flywheel 5 Drive motor 11 Hydraulic pump 13 Electromagnetic directional switching proportional valve (servo valve) 15 Servo cylinder 25 Electromagnetic directional switching valve 101 Hydraulic turret punch press 123 Hydraulic cylinder 145 Swash plate type variable displacement hydraulic pump 151 Electromagnetic Directional Switching Proportional Valve

Claims (1)

[Claims] 1. In a hydraulic circuit of a hydraulic turret punch press, a swash plate type variable displacement hydraulic pump is provided as a hydraulic power source, and a control circuit comprising another hydraulic pump, a servo valve and a servo cylinder is provided for displacement control, A hydraulic circuit for a hydraulic turret punch press, characterized in that a flywheel is attached to the drive shaft of a plate type variable displacement hydraulic pump, and an electromagnetic directional switching valve is used to switch the direction of pressure oil in the hydraulic cylinder.