KR20070053972A - Air cylinder having warning signal generator - Google Patents

Abstract

The present invention relates to a pneumatic cylinder equipped with a warning signal generator. The present invention relates to a pneumatic cylinder having at least one air line connected to supply air in a cylinder body to linearly move an internal piston and a piston rod connected thereto, the linear motion range when the piston is linearly moved at a predetermined reference speed. A sensor inserted into a wall of a cylinder body corresponding to at least one end of both ends of the sensor to detect movement of the piston; a time required for the reciprocating motion of the piston by a signal input from the sensor or one downward straight line After calculating the time required for the movement or the upward linear motion, the piston compares with the time required for the reciprocating motion during the linear motion at the reference speed or with the preset theoretical time for the one downward linear motion or the upward linear motion. A controller which controls to generate a warning signal when there is a mismatch; And a warning signal generator for generating a warning signal under the control of the controller.

According to the pneumatic cylinder equipped with a warning signal generator of the present invention, by generating a warning signal when the pneumatic cylinder is abnormal operation, it is possible to monitor the operation of the pneumatic cylinder in real time, the piston is out of the reference speed If you exercise, you can respond quickly.

Pneumatic Cylinder, Piston, Sensor, Warning Signal Generator

Description

Pneumatic cylinder with warning signal generator {AIR CYLINDER HAVING WARNING SIGNAL GENERATOR}

1 is a schematic configuration diagram of a speed regulating device of a double-acting pneumatic cylinder.

2 is a schematic configuration diagram of a pneumatic cylinder equipped with a warning signal generator according to an embodiment of the present invention.

3 is a schematic configuration diagram of a pneumatic cylinder equipped with a warning signal generator according to another embodiment of the present invention.

<Explanation of symbols for the main parts of the drawings>

One; Cylinder body 2; piston

3; Piston rods 8,9; Air inlet pipe

20,22, 30,32; Sensor 40; Control

50; Warning signal generator

The present invention relates to a pneumatic cylinder with a warning signal generator, and more particularly to a pneumatic cylinder with a warning signal generator for monitoring the abnormal operation of the pneumatic cylinder in real time.

In general, there is a hydraulic cylinder using a liquid and a pneumatic cylinder using a gas according to the type of the working fluid in the apparatus for changing the pressure in the cylinder by adjusting the flow of air or fluid and converting it into a linear movement of the piston.

Among them, pneumatic cylinders using air as a working fluid have a small size and light weight and are less susceptible to wafer contamination. Therefore, pneumatic cylinders are widely used in wafer holding devices and transfer devices as mechanical elements for various linear motions in semiconductor processing equipment.

The pneumatic cylinder includes a cylinder body, a piston for receiving air pressure, a piston rod connected to the piston for transmitting power, an air inlet and outlet pipe for injecting air into the cylinder body, an air valve for regulating the flow of air, It consists of a piston speed adjusting screw that controls the air volume of the inlet and outlet pipes.

Pneumatic cylinders are provided with a single air line, a single-acting type capable of only one-way speed control, and two or more air lines provided with a double-acting type capable of bi-directional speed control.

Hereinafter, a conventional pneumatic cylinder will be described with reference to FIG. 1.

1 is a schematic configuration diagram of a speed regulating device of a double-acting pneumatic cylinder.

As shown in FIG. 1, the cylinder body 1, which is sufficiently sealed with external air, includes a piston 2 therein and a piston rod 3 connected vertically to the piston 2 to transmit power to the outside. Above and below the cylinder body, there are air inlet and outlet pipes 8 and 9 for inlet and outlet of air, respectively.

In general, the two spaces isolated by the piston 2 are called the first air chamber 10 and the second air chamber 11, and the difference in the air pressure between the first air chamber 10 and the second air chamber 11 It causes the movement of the piston (2).

For the pressure difference between the two chambers 10 and 11, the air inlet and outlet pipes 8 and 9 which supply air to the two chambers 10 and 11 and the air inflows and outflows of the two chambers are relative to each other. There are two air valves (4) and (5) to operate in order to prevent sudden air inflow and outflow and to adjust the amount of inflow and outflow air so that the piston (2) maintains a constant speed in the upward and downward directions, respectively. There are up and down piston speed adjusting screws (6) (7).

However, the conventional pneumatic cylinder configured as described above has the following problems.

 That is, since there is no device that can check the operation state of the piston of the pneumatic cylinder used for lifting and lowering the lift pin or transferring the wafer, the piston becomes slower than the standard speed due to the change in the amount of air introduced or breakage of the pneumatic cylinder. Even if the wafer is slid or shifted out of position or faster, there is a problem in that a quick response cannot be taken.

Therefore, the present invention has been made to solve the above problems, an object of the present invention, by inserting a sensor that can detect the movement of the piston into the wall of the cylinder body to the warning signal when the piston operates abnormally The present invention provides a pneumatic cylinder equipped with a warning signal generator capable of monitoring the operation state of the piston and quickly responding to abnormal operation of the piston by controlling the power generation to occur.

In order to achieve the above object, the present invention in the pneumatic cylinder having at least one air line connected to supply air in the cylinder body to linearly move the piston and the piston rod connected thereto, the piston is a predetermined A sensor inserted into a wall of a cylinder body corresponding to at least one end of both ends of a linear motion range at a reference speed to detect a movement of the piston; a reciprocating motion of the piston by a signal input from the sensor After calculating the time required or the time required for one down linear movement or up linear movement, the piston takes time for reciprocating movement or one down linear movement or up linear movement at linear speed. To generate a warning signal if there is a mismatch between them A control unit for controlling; And a warning signal generator for generating a warning signal under the control of the controller.

The sensor is a proximity sensor, it is preferable to detect the movement of the piston when the piston contacts the inner wall of the cylinder body is installed.

In addition, the sensor may be an optical sensor, in which case the light emitting sensor and the light receiving sensor are preferably installed to face each other.

The theoretical time preset in the controller is preferably a range value.

Also, preferably, the warning signal generator displays the warning signal with at least one of a lamp and an alarm.

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

2 is a schematic configuration diagram of a pneumatic cylinder equipped with a warning signal generator according to an embodiment of the present invention. In FIG. 2, the same components as in FIG. 1 are denoted by the same reference numerals, and a detailed description thereof will be omitted.

As shown in FIG. 2, the pneumatic cylinder is supplied through a cylinder body 1, air inlet and outlet pipes 8 and 9 and air inlet and outlet air to and from the cylinder body 1. A piston (2) for vertical movement in the interior of the cylinder body (1) by receiving the pressure of air, it is provided with a piston rod (3) connected vertically to the piston (2) for transmitting power to the outside.

The present invention relates to a warning signal generator capable of real-time monitoring the abnormal operation of such a conventional pneumatic cylinder, the warning signal generator of the pneumatic cylinder according to the present invention is a sensor (20, 22), the control unit 40 and the warning It consists of a signal generator 50.

The sensor is an optical sensor, and includes a light emitting sensor 20 and a light receiving sensor 22. 2 shows a pair of opposing optical sensors 20, 22, but the scope of the present invention is not particularly limited by the position or number of sensors as long as the optical sensor can detect the movement of the piston. Does not.

The optical sensors 20 and 22 are inserted into the wall of the cylinder body to detect the movement of the piston 2. The reason why the optical sensors 20 and 22 are inserted into the wall of the cylinder body 1 is that the piston 2 reciprocates while being in contact with the inner wall of the cylinder body 1. This is to prevent the optical sensors 20 and 22 from being damaged by the contact of.

The optical sensors 20 and 22 are installed in a range in which the piston 2 linearly moves once, and are installed at at least one end of both ends of the linear movement range. In other words, it is preferable that the piston 2 is located immediately below the piston 2 before the downward linear movement or the piston 2 immediately above the piston 2 before the upward linear movement.

This is due to the principle of detecting the movement of the piston 2 using the photosensors 20 and 22, and the principle of detecting the movement of the piston 2 using the photosensors 20 and 22 with reference to FIG. Briefly explain.

Before the piston 2 starts the downward linear motion, since there is no object blocking the signal emitted from the light emitting sensor 20, the light receiving sensor 22 may receive the optical signal. However, when the piston 2 moves downward and reaches the portion where the light emitting sensor 20 is attached, the signal emitted from the light emitting sensor 20 is blocked by the piston 2, so that the light receiving sensor 22 does not receive the light emitting signal. can not do it.

If the piston 2 continues downward, this time the piston rod 3 blocks the light emitted from the light emitting sensor 20, so that the light receiving sensor 22 cannot receive the light emitting signal.

As such, the light receiving sensor 22 does not receive the signal emitted from the light emitting sensor 20 until the piston 2 moves downward and then goes straight upward again and passes the portion where the optical sensors 20 and 22 are installed. It is not possible to receive the signal emitted from the light emitting sensor 20 until the piston (2) continues to rise above the optical sensor (20, 22).

At this time, the light receiving sensor 22 sends a predetermined signal to the control unit 40 to inform whether the light signal receiving from the light receiving sensor 22.

The controller 40 receives a signal from the light receiving sensor 22 and calculates a time required for the piston 2 to reciprocate once.

At this time, the control unit 40 has a predetermined theoretical time required when the piston 2 reciprocates at a reference speed. Here, 'reference speed' refers to the speed at which the piston (2) is ideally operated in consideration of the use of the pneumatic cylinder, and 'theoretical time' refers to the time required when the piston (2) reciprocates once at the reference speed. Say

In this case, the 'theoretical time' input to the controller 40 may be a specific single value, but is preferably input as a constant range value having an error range in consideration of the error of the device. For example, when the theoretical time required for one reciprocating motion of the piston 2 is 5 seconds, it is preferable to input 'theoretical time' to the controller 40 as 4.7 seconds to 5.3 seconds.

The controller 40 calculates the actual time required for the piston 2 to reciprocate once, and compares it with a preset theoretical time, and controls to generate a warning signal when there is a mismatch.

At this time, the warning signal is generated through the warning signal generating unit 50, it is generated in the form of a lamp or alarm, etc. to inform the operator of the abnormal operation of the piston (2).

Hereinafter, the operation of the warning signal generator of the pneumatic cylinder according to the present invention will be described with reference to FIG.

First, the piston 2 is positioned above the light sensors 20 and 22.

Next, the air is supplied through the upper air inlet and outlet pipe 8, and when the air is supplied to the inside of the cylinder body 1, the piston 2 moves downward. At this time, the speed at which the piston 2 descends depends on the amount of air supplied through the upper air supply pipe 8.

When the piston 2 is positioned above the light sensors 20 and 22, the light receiving sensor 22 receives a signal emitted from the light emitting sensor 20 and informs the controller 40 that the signal has been received.

Subsequently, when the piston 2 moves downward in a straight line to block a signal emitted from the light emitting sensor 20, the light receiving sensor 22 does not receive a signal, and the light receiving sensor 22 does not receive a signal. (40).

The light receiving sensor 22 does not receive a signal emitted from the light emitting sensor 20 until the piston 2 continues to move in a straight line and then moves upward in a straight line again to be positioned above the light emitting sensor 20.

Subsequently, when the piston 2 moves upward and positioned above the light sensors 20 and 22, the light receiving sensor 22 receives a signal emitted from the light emitting sensor 20, and the controller 40 receives the signal. To tell.

Then, the control unit 40 causes the light receiving sensor 22 to receive the signal of the light emitting sensor 20 as the piston 2 moves downward, and then the piston 2 moves upward to receive the signal for the first time. The time taken between time points is calculated and compared with the preset theoretical time.

As a result of the determination, if the theoretical time preset in the control unit 40 and the time required for the piston 2 to actually reciprocate once, coincide with each other, the control unit 40 does not generate a warning signal.

On the contrary, if the theoretical time preset in the controller 40 and the time required for the piston 2 to actually reciprocate once are inconsistent with each other, the warning signal generator 50 controls the warning signal to be generated.

When the controller 40 is commanded to generate a warning signal, the warning signal generator 50 displays a warning signal by a lamp or an alarm.

According to the pneumatic cylinder equipped with the warning signal generator of the present invention, it is possible to monitor the operating state of the piston, so that when the piston does not reciprocate at a reference speed suitable for the use of the pneumatic cylinder, it is possible to quickly take a proper response. have.

Meanwhile, a proximity sensor as well as an optical sensor may be used to monitor the operating state of the piston, which will be described with reference to FIG. 3.

3 is a schematic configuration diagram of a pneumatic cylinder equipped with a warning signal generator according to another embodiment of the present invention. In FIG. 3, the same components as in FIG. 2 are denoted by the same reference numerals, and a detailed description thereof will be omitted.

As shown in Figure 3, the warning signal generator of the pneumatic cylinder of the present invention is a conventional pneumatic cylinder consisting of a cylinder body (1), a piston (2), a piston rod (3), air inlet and outlet pipes (8, 9) It further comprises a warning signal generator including a sensor (30, 32), the control unit 40 and the warning signal generator 50.

The sensors 30 and 32 are proximity sensors, which are non-contact type sensors that detect the presence or absence of an object to be detected when the detector is in close proximity, rather than a detection method by mechanical contact as in a conventional micro switch or a limit switch.

The proximity sensors 30 and 32 are inserted into the wall of the cylinder body 1. The proximity sensors 30 and 32 are configured to detect when a moving object, ie, the piston 2 is close, and send a predetermined signal to the controller 40.

In the present invention, when the proximity sensor (30, 32) to set the proximity distance that can detect the object, considering that the piston (2) reciprocating in contact with the inner wall of the cylinder body (1), the proximity sensor ( When the piston 2 contacts the inner wall of the cylinder body 1 in which the 30 and 32 are installed, the proximity sensors 30 and 32 set to detect the presence of the piston 2.

Therefore, when the piston 2 is located above the first proximity sensor 30, no signal is input to the controller 40, and the piston 2 moves downward in a straight line to install the first proximity sensor 30. The signal is input to the control unit 40 at the time of contact with.

After that, when the piston 2 continues downward and contacts the inner wall of the cylinder body in which the second proximity sensor 32 is installed, the signal is transmitted to the controller 40 again.

The controller 40 calculates a time taken between the time point at which the signal is input from the first proximity sensor 30 and the time point at which the signal is input from the second proximity sensor 32 and compares the time with a preset theoretical time.

Here, the 'theoretical time' preset in the control unit 40 means that when the piston 2 is linearly moved to the reference speed so as to be suitable for the use in which the pneumatic cylinder is used, it is required to perform one downward linear movement or one upward linear movement. Say time. Of course, even in this case, the theoretical time is preferably input as a range value.

The control unit 40 compares the theoretical time with the time actually required for the linear movement of the piston 2 once, and controls the warning signal generator 50 to generate a warning signal if there is a mismatch.

 According to the warning signal generating device of the pneumatic cylinder of the present invention, since the piston generates a warning signal immediately when the linear motion is out of the reference speed, it is possible to prompt the operator for abnormal operation of the piston.

In the above, the best embodiment has been disclosed in the drawings and the specification. Although specific terms have been used herein for the purpose of description, they are used only for the purpose of describing the present invention and are not intended to limit the meaning or the scope of the invention as set forth in the claims. Therefore, those skilled in the art will understand that various modifications and equivalent other embodiments are possible from this. Therefore, the true technical protection scope of the present invention should be defined by the technical spirit of the appended claims.

According to the present invention, by inserting a sensor that can detect the movement of the piston into the wall of the cylinder body to control the piston to generate a warning signal when the abnormal operation of the piston can monitor the operating state of the piston, abnormal operation of the piston Because it can respond quickly to, it is possible to minimize the damage of the wafer and the damage of the device due to the abnormal operation of the pneumatic cylinder.

Claims (5)

In a pneumatic cylinder having at least one air line connected to supply air in a cylinder body to linearly move an internal piston and a piston rod connected thereto, A sensor inserted into a wall of a cylinder body corresponding to at least one end of both ends of a linear motion range when the piston is linearly moved at a predetermined reference speed to detect movement of the piston; After calculating the time required for the reciprocating motion of the piston or the time required for one down linear motion or the up linear motion by the signal input from the sensor, the piston is required for the reciprocating motion during the linear motion at the reference speed. A controller configured to generate a warning signal when there is a mismatch in comparison with a preset theoretical time required for a time or a single downward linear movement or an upward linear movement; And A warning signal generator for generating a warning signal under control of the controller; Pneumatic cylinder provided with a warning signal generator comprising a. The method of claim 1, The sensor is a proximity sensor, the pneumatic cylinder with a warning signal generating device, characterized in that for detecting the movement of the piston when the piston contacts the inner wall of the cylinder body is installed. The method of claim 1, The sensor is an optical sensor, the pneumatic cylinder with a warning signal generator, characterized in that the light emitting sensor and the light receiving sensor is installed to face each other. The method of claim 1, The theoretical time preset in the controller is, Pneumatic cylinder with a warning signal generator characterized in that the range value. The method of claim 1, The warning signal generator, A pneumatic cylinder with a warning signal generator, characterized in that for displaying the warning signal to at least one of the lamp or alarm.

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