JP3085306U - Bending equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To use a pump of an electronic control type to program hydraulic power for an actuator according to a desired production amount and reduce energy consumption. Obtain a bending device. A bending unit (8) having hydraulic actuators (12, 15) controlled by a hydraulic pump (16).
Closed loop electronic control system 25,2
Reference numerals 9, 35, 37, and 39 denote an inductive position transducer 35 for detecting the position of the valve spool 26, a swing angle transducer 37 for detecting the swing angle of the pump 16, and a pressure detection for the pump supply path. Pressure transducers 39, and these transducers 35, 3
Position signal, swing angle signal and pressure signal 3 from 7, 39
4, 36, 38 and a program electronic control unit 29 for receiving commands 30, 31, 32 for predetermined pressure, power and flow values and outputting a control signal 28 to the proportional solenoid 27.

Description

[Detailed description of the invention]

[0001]

[Technical field to which the invention belongs]

 TECHNICAL FIELD The present invention relates to a bending apparatus for bending a general-purpose plate material known in the art as a panel bending machine.

These panel bending machines are capable of automatically moving a blank of a metal plate onto a horizontal plane in front of a bending press provided with a bending unit having one or two bending blades, With this bending unit, a large number of bendings of variable dimensions, angles and directions can be performed on each side of the blank. The bending press further includes a fixed counter blade and a variable-size blank holder that cooperates with the counter blade to clamp and bend the vicinity of the edge of the blank. The bending unit and the blank holder are operated by hydraulic actuators controlled by hydraulic cylinders. An example of such a bending machine is described in European Patent Publication No. 293964.

[0003] The advantages of this bending machine are the constant production volume and the flexibility of production and programming. And there are few disadvantages.

[0004] However, there is the disadvantage that the thermal efficiency is low in that it dissipates as heat and the hydraulic energy to be cooled by a suitable cooler is quite large. In fact, the controllable actuator of the bending unit is powered by a constant power hydraulic pump, which is powered by a hydraulic circuit with a pressure limiting device and a flow regulator. The inertia of the operation of the hydraulic pump is energy dissipated as heat.

[0005] It is therefore an object of the present invention to provide a bending apparatus for metal sheets which can programmably reduce energy when maximum production is not required.

In order to achieve this object, the present invention relates to a bending apparatus comprising a bending unit moved by a hydraulic actuator controlled by a hydraulic pump, comprising: A variable feed pump having a closed loop electronic control system for controlling power is provided, and the electronic control system is provided with an electric control proportional valve.

By using an electronically controlled pump, the hydraulic power for the actuator can be programmed according to the desired output. The new panel bending machine according to the present invention can reduce energy consumption compared to the conventional panel bending machine provided with a constant power hydraulic pump.

[0008]

[Embodiment of the invention]

 Next, a preferred embodiment of the present invention will be described with reference to the drawings.

The bending press shown in FIG. 1 has a fixed base 1, which supports a counter blade 2, and moves the counter blade 2 against a metal plate material moved by a manipulator (not shown). The side edge of the blank 3 is placed.

The blank holder 4 is operated in conjunction with the counter blade 2 to clamp the edge of the metal plate. The blank holder is attached to the front end of the movable support 5, and the rear end of the support 5 is hinged to the rear part of the fixed base 1 by the hinge 6. The support 5 is raised and lowered by a plurality of hydraulic cylinders 7.

The bending unit 8 has a blade support 9 common to the two bending blades 10 and 11 that cooperates with the counter blade 2 to bend the clamp edge of the metal plate. The bending unit 8 is subjected to a combined movement of horizontal movement and vertical movement by a hydraulic actuator, and the hydraulic actuator moves between a rear portion of the fixed base 1 and a lever 13 having a fixed hinge portion 14 and a movable hinge portion 100. And a hydraulic cylinder 15 interposed between the blade support 9 and the fixed base 1.

The hydraulic actuators 12, 15 are controlled diagrammatically in FIG. 2 by a control system (S denotes a fluid tank) having a pump 16 of variable feed rate.

The variable feed pump 16 is driven by an electric motor 17 and, as usual, a pump body 18 and a rotatable and tiltable swash plate acting on an axial piston (not shown). 19, and performs fluid supply at a flow rate depending on the swing angle of the swash plate 19. This swing angle can take the maximum value when the piston 20 slidably accommodated in the hydraulic cylinder 21 receives the pump pressure and is pressed by the spring 22. It can be reduced by the action of the control piston 23, which is slidably housed in a hydraulic cylinder 24 controlled by an electrically controlled proportional valve 25 provided in a closed loop control system.

The proportional valve 25 is provided with a valve spool 26 which is pressed to the position shown in FIG. 2 by a spring 41 and is controlled by a proportional control solenoid 27, which is controlled by an electronic program control unit. The electronic program control unit 29 receives a control signal 28 from the operator 29 or receives a command value provided by an operator or a program electronic control system, for example, a pressure value 30, a power value 31 and a flow value 32. 29 is provided with an amplification stage 33 which comprises a valve spool position signal 34 from an inductive position transducer 35 associated with the valve spool 26 and a swing angle transducer 37 associated with the control piston 23. Swing angle signal 36, pump pressure signal 38 from pressure transducer 39 arranged in the pump feed line. Is input.

A pressure limiting device 40 is provided between the pump supply path and the fluid tank S.

When pump 16 is at rest and pressure is low in the control system, swash plate 19 is held in a maximum tilt position by spring 22.

When the pump 16 is driven to rotate and the proportional solenoid 27 is deenergized, the valve spool 26 is pressed and displaced by the spring 41 to the position shown in FIG. When applied, the control system is adjusted to zero stroke pressure. The balance between pump pressure and spring 22 force is obtained at a value between 8 and 10 bar. This basic setting is applied to the inactive electronic control unit 29.

When the electronic control unit 29 is active, the actual pressure value (signal 38), valve spool position (signal 34) and swing angle (signal 36) are compared with the values of commands 30, 31, and 32, respectively. I do. When a control error is detected, processing is performed, a control signal 28 for the proportional solenoid 27 is generated, and the values 34, 36, 38 detected from the center position of the valve spool 26 in accordance with the above-described error are commanded. Move until it is equal to the value of 30, 31, 32.

When the program control unit 29 requests an increase in the swing angle in order to increase the flow rate from the pump 16 to the actuators 12 and 15, the control signal 28 increases the current flowing through the solenoid 27, and The valve spool 26 is moved rightward from the center position until the angle reaches the required value. Conversely, when the valve spool 26 is moved to the left due to the decrease in the solenoid current, the swing angle is reduced, and the flow rate of the fluid to the actuators 12 and 15 is reduced.

In particular, by acting on the power value command 31, the hydraulic power delivered from the pump 16 to the actuators 12, 15 can be changed.

In this way, the hydraulic power supplied to the actuator can be programmed to reduce energy consumption depending on the required production.

[Brief description of the drawings]

FIG. 1 is an explanatory view of mechanical parts of a bending press provided with a bending unit for controlling hydraulic pressure.

FIG. 2 is an explanatory diagram of a control system for a hydraulic actuator of the bending unit shown in FIG.

[Explanation of symbols]

 1 Fixed base 2 Counter blade 3 Blank 4 Blank holder 5 Support 6 Hinge 7 Hydraulic cylinder 8 Bending unit 9 Blade support 10 Bending blade 11 Bending blade 12 Hydraulic cylinder 13 Lever 14 Fixed hinge 15 Hydraulic cylinder 16 Pump 17 Electric motor 18 Pump body 19 Swash plate 20 Piston 21 Hydraulic cylinder 22 Spring 23 Control piston 24 Hydraulic cylinder 25 Proportional valve 26 Valve spool 27 Proportional control solenoid 28 Control signal 29 Electronic program control unit 30 Pressure value Commands 31 Power value commands 32 Flow rate commands 33 Amplification stage 34 Valve spool position signal 35 Inductive position transducer 36 Swing angle signal 37 Swing angle transducer 38 Pump pressure signal 39 Pressure transducer 40 Pressure limiting device 41 Spring

Claims (4)

[Utility model registration claims] 1. A bending apparatus comprising a bending unit (8) moved by a hydraulic actuator (12, 15) controlled by a hydraulic pump (16), wherein the hydraulic pump (16) comprises: A closed-loop electronic control system for controlling flow, pressure and power (25, 29, 35,
37. A bending machine, characterized in that it is a variable feed pump provided with 37, 39) and the electronic control system is provided with an electrically controlled proportional valve (25). 2. The pump according to claim 1, wherein the proportional valve is a pump.
A valve spool (26) for controlling the swing angle of the pump, and a proportional solenoid (27) for moving the valve spool (26) to a position corresponding to a desired swing angle of the pump (16).
2. The bending apparatus according to claim 1, wherein the bending apparatus has: 3. The control system (25, 29, 35, 37,
39) an inductive position transducer (35) associated with the valve spool (26) for detecting the position of the valve spool (26), and the inductive position transducer (35) for detecting the swing angle of the pump (16). A swing angle converter (37) associated with the pump (16), a pressure converter (39) arranged in the pump feed line to detect the pressure in the pump feed line, and each of these converters (35, 37, 39), the swing angle signal and the pressure signal (34, 36, 38) and a predetermined pressure value,
A program electronic control unit (2) that receives a command of a power value and a flow value (30, 31, 32) and outputs a control signal (28) to the proportional solenoid (27).
3. The bending apparatus according to claim 2, wherein the bending apparatus has the following configuration. 4. The bending apparatus according to claim 1, wherein the power supplied by the pump (16) is adjustable by acting on a power value command (31).