JP3127171U - Air cylinder drive - Google Patents

Abstract

To provide an air cylinder drive device that can perform precise position control and force control using an air cylinder having a rod that has been used in conventional ON / OFF control.
An air cylinder having a rod, an air servo valve connected to the air cylinder, a controller for driving the air servo valve, and a displacement meter connected to the rod of the air cylinder and detecting displacement thereof. The controller 6 amplifies the deviation between the input command signal and the displacement signal of the displacement meter 7 to drive the air servo valve 3, and performs feedback control so that the deviation becomes zero. Alternatively, a load cell connected to the rod of the air cylinder 1 and detecting the load force of the rod is provided, and the controller 6 drives the air servo valve 3 by amplifying the deviation between the input command signal and the load force signal of the load cell. Is controlled to be zero. The load cell is interposed between a rod and a member to be loaded.
[Selection] Figure 1

Description

  The present invention relates to a component fatigue endurance tester or positioning device, and more particularly to a drive device for an air cylinder constituting the device.

  Conventionally, general-purpose air cylinders are used for the purpose of moving a load by a predetermined distance, for example, as a load mechanism in a material test. FIG. 3 is a diagram showing an outline of a general air cylinder driving device. In FIG. 3, the air cylinder 1 is composed of a tube, a piston, a rod, and the like, and is a general general-purpose product. The compressed air source 2 supplies compressed air to the electromagnetic valve 31. The pressure of the compressed air is, for example, 0.3 to 0.7 MPa. The electromagnetic valve 31 switches between air supply and exhaust for the two air pipes connected to the air cylinder 1 in accordance with an input ON / OFF control signal. The load object 32 is fixed by the fixing jigs 9 and 10. The jig 9 is fastened to the tip of the rod, and the jig 10 is fixed together with the air cylinder 1 to a housing (not shown).

  When an ON / OFF control signal for applying a load load in the compression direction is input to the load object 32, the electromagnetic valve 31 supplies compressed air to the left chamber of the air cylinder 1 and at the same time the right chamber of the air cylinder 1. The air is released into the atmosphere. When an ON / OFF control signal for applying a load load in the tensile direction is input to the load object 32, the air supply / exhaust of the left and right rooms are reversed. When the stop position of the rod is set at a position other than the stroke end of the air cylinder 1, a stopper (not shown) is disposed at a predetermined position. The air cylinder driving device shown in FIG. 3 is a device that operates by ON / OFF control, and it is difficult to perform precise position control and force control.

However, in recent years, a system for improving position control / force control characteristics using a servo mechanism has been proposed, and a high-performance actuator using air pressure has been put into practical use. A fatigue endurance tester has been proposed in which a control system similar to that of a hydraulic servo is built with air pressure to achieve highly accurate control. (For example, see Non-Patent Document 1)
Shimazu Review, Vol. 62, No.3, No.4, 227-233 (2006)

  Provided is an air cylinder driving device capable of performing precise position control and force control using an air cylinder having a rod that has been used in conventional ON / OFF control.

  In an air cylinder driving apparatus having an air cylinder having a rod which is supplied with compressed air from a compressed air source through a valve and is actuated by the compressed air, the valve is constituted by an air servo valve and the air servo valve is driven and controlled. And a displacement meter connected to the rod of the air cylinder and detecting the displacement thereof, the controller controls so that the deviation between the input command signal and the displacement signal of the displacement meter becomes zero. The displacement meter is preferably installed in parallel with the air cylinder.

  In an air cylinder driving apparatus having an air cylinder having a rod which is supplied with compressed air from a compressed air source through a valve and is actuated by the compressed air, the valve is constituted by an air servo valve and the air servo valve is driven and controlled. And a load cell connected to the rod of the air cylinder for detecting the load force of the rod, and the controller controls the deviation between the input command signal and the load force signal of the load cell to be zero. . The load cell is preferably interposed between the rod and the member to be loaded.

  In the air cylinder drive device of the present invention, a general-purpose air cylinder that has been conventionally used in ON / OFF control is servo-controlled, and the rod of the air cylinder is controlled and driven by an arbitrary position or an arbitrary load force. Application to a small fatigue endurance tester or positioning device that is not used is expected. Further, in this small fatigue endurance tester, since the actuator of the main part is composed of a general-purpose air cylinder, provision of an inexpensive device can be expected.

  The compressed air supplied from the compressed air source passes through the filter, is purified, and is adjusted to a constant pressure by a regulator.

  Hereinafter, two embodiments of the present invention will be described with reference to the drawings.

  First, a first embodiment will be described with reference to FIG. FIG. 1 is a diagram in which a displacement meter is installed in parallel with an air cylinder in the air cylinder driving device of the present invention. In FIG. 1, an air cylinder 1 is composed of a tube, a piston, a rod, and the like, and is a general-purpose product that has been used in conventional ON / OFF control. The inner diameter of the tube is, for example, 80 mm. The compressed air source 2 supplies compressed air to the air servo valve 3. The pressure of the compressed air is, for example, 0.5 MPa. The air servo valve 3 changes the air flow rate of the air pipes 4 and 5 connected to the air cylinder 1 in accordance with the input control signal, and switches between air supply and exhaust to the air pipes 4 and 5 in accordance with the polarity of the control signal. To do. Exhaust gas from the air pipe 4 or the air pipe 5 is released to the atmosphere through the atmosphere opening 3 a provided in the air servo valve 3. The controller 6 amplifies the difference between the displacement signal and the command signal, transmits it to the air servo valve 3 as a control signal, and drives it. The displacement meter 7 detects the displacement of the rod and transmits it to the controller 6 as a displacement signal. The test piece 8 is fixed by fixing jigs 9 and 10. The jig 9 is disposed at the tip of the rod, and the jig 10 is disposed in a housing (not shown). The air cylinder 1 and the air servo valve 3 are fixed to a base plate 11, and the base plate 11 is fixed to a housing (not shown). The detent 12 functions as a guide for preventing rotation of the rod.

  When the rod position (displacement signal) is on the left side of the position indicated by the command signal, the controller 6 amplifies the difference and transmits it to the air servo valve 3 as a control signal. The air servo valve 3 supplies compressed air to the left chamber of the air cylinder 1 via the air pipe 4 and simultaneously exhausts air in the right room via the air pipe 5 to move the rod position to the right. The air flow rate of supply / exhaust air is controlled by a control signal. When the rod position (displacement signal) is to the right of the position indicated by the command signal, the polarity of the control signal is reversed and the air servo valve 3 supplies compressed air to the right chamber of the air cylinder 1 via the air pipe 5. At the same time, the air in the left room is exhausted through the air pipe 4 and the position of the rod is moved to the left.

  Since the present invention has the above-described configuration, the apparatus shown in FIG. 1 drives the air servo valve 3 by amplifying the deviation between the command signal (test waveform) input to the controller 6 and the displacement signal of the displacement meter 7. It is a device that performs feedback control so that the deviation becomes zero, and functions as a small fatigue endurance tester having a capacity of, for example, 2 kN and a stroke of, for example, ± 25 mm.

  Next, a second embodiment will be described with reference to FIG. FIG. 2 is a view in which a load cell is interposed between a rod and a member to be loaded in the air cylinder driving device of the present invention. In FIG. 2, the air cylinder 1 is a general-purpose product that includes a tube, a piston, a rod, and the like, and has been used in conventional ON / OFF control. The inner diameter of the tube is, for example, 80 mm. The compressed air source 2 supplies compressed air to the air servo valve 3. The pressure of the compressed air is, for example, 0.5 MPa. The air servo valve 3 changes the air flow rate of the air pipes 4 and 5 connected to the air cylinder 1 in accordance with the input control signal, and switches between air supply and exhaust to the air pipes 4 and 5 in accordance with the polarity of the control signal. To do. Exhaust gas from the air pipe 4 or the air pipe 5 is released to the atmosphere through the atmosphere opening 3 a provided in the air servo valve 3. The controller 6 amplifies the difference between the load force signal and the command signal, transmits it to the air servo valve 3 as a control signal, and drives it. The load cell 21 is disposed at the tip of the rod, detects the load force, and transmits it to the controller 6 as a load force signal. The test piece 8 is fixed by fixing jigs 9 and 10. The jig 9 is disposed at the tip of the rod via the load cell 21, and the jig 10 is disposed in a housing (not shown). The air cylinder 1 and the air servo valve 3 are fixed to a base plate 22, and the base plate 22 is fixed to a housing (not shown). The detent 12 functions as a guide for preventing rotation of the rod.

  When the force on the test piece 8 (load force signal) is smaller than the force indicated by the command signal, the controller 6 amplifies the difference and transmits it to the air servo valve 3 as a control signal. The air servo valve 3 supplies compressed air to the left chamber of the air cylinder 1 through the air piping 4 and simultaneously exhausts air in the right chamber through the air piping 5 to move the rod to the right. The air flow rate of supply / exhaust air is controlled by a control signal. When the force on the test piece 8 (load force signal) is larger than the force indicated by the command signal, the polarity of the control signal is reversed, and the air servo valve 3 is compressed air to the right chamber of the air cylinder 1 via the air pipe 5. At the same time, the air in the left room is exhausted through the air pipe 4 and the rod is moved to the left.

  Since the present invention has the above configuration, the apparatus shown in FIG. 2 drives the air servo valve 3 by amplifying the deviation between the command signal (test waveform) input to the controller 6 and the load force signal of the load cell 21. It is a device that performs feedback control so that the deviation becomes zero, and functions as a small fatigue endurance tester having a capacity of, for example, 2 kN and a stroke of, for example, ± 25 mm.

In the first embodiment shown in FIG. 1, the apparatus functions as a small fatigue endurance tester, but the test piece 8 and jigs 9 and 10 are removed and a load is applied to the rod end of the air cylinder 1. By arranging the object, the device functions as a positioning device. The present invention can also be applied to such a positioning device.
In the first embodiment shown in FIG. 1, the load cell for detecting the load force is not provided. However, the load cell is interposed between the jig 9 and the rod tip, and the output signal (load force signal) is output. You may make it transmit to the controller 6. FIG. The controller 6 samples the relationship between the amount of deformation of the test piece 8 and the load using the displacement signal and load force signal transmitted, and displays them on the display. The present invention can be applied to a small fatigue durability tester having such a function, and the apparatus is not limited to the illustrated example.

  The present invention relates to a component fatigue endurance tester or a positioning device, and more particularly to an air cylinder driving device constituting the device.

It is the figure which installed the displacement meter in parallel with the air cylinder with the air cylinder drive device of the present invention. It is the figure which interposed the load cell between the rod and the member loaded with the air cylinder drive device of this invention. It is a figure which shows the outline of a general air cylinder drive device.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Air cylinder 2 Compressed air source 3 Air servo valve 3a Atmospheric opening 4 Air piping 5 Air piping 6 Controller 7 Displacement meter 8 Test piece 9 Jig 10 Jig 11 Base plate 12 Non-rotating 21 Load cell 22 Base plate 31 Electromagnetic valve 32 Load Object

Claims (4)

  In an air cylinder driving apparatus having an air cylinder having a rod which is supplied with compressed air from a compressed air source through a valve and is actuated by the compressed air, the valve is constituted by an air servo valve and the air servo valve is driven and controlled. And a displacement meter connected to the rod of the air cylinder for detecting the displacement, the controller controlling the deviation between the input command signal and the displacement signal of the displacement meter to be zero. A featured air cylinder drive device.   In an air cylinder driving apparatus having an air cylinder having a rod which is supplied with compressed air from a compressed air source through a valve and is actuated by the compressed air, the valve is constituted by an air servo valve and the air servo valve is driven and controlled. And a load cell connected to the rod of the air cylinder for detecting the load force of the rod, and the controller controls the deviation between the input command signal and the load force signal of the load cell to be zero. An air cylinder driving device.   2. The air cylinder driving device according to claim 1, wherein the displacement meter is installed in parallel with the air cylinder.   The air cylinder driving device according to claim 2, wherein the load cell is interposed between the rod and a member to be loaded.

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