JPH06264900A - Vacuum generating device - Google Patents

Abstract

PURPOSE:To provide a vacuum generating device having vacuum generating function and control function in one device. CONSTITUTION:Through a first port 30, pressure air is led into a main body 28. Through a second port 32, outside air is led into the main body part 28. Through a third port 34, air staying inside the main body part 28 is discharged outside. The first port 30 and the third port 34 are connected to each other through first flow passage 46a, 46b, 46c, and 46d. In second flow passages 46e, 46f, one-side ends thereof are connected to the second port 32, and the other-side ends are perpendicularly connected to the first flow passages 46a, 46b, 46c, 46d. A movement switching part 36 is formed movably between a first position and a second position. When the movement switching part 36 is positioned in the first position, the first flow passages 46a, 46b, 46c, and 46d are blocked in a space between the first port 30 and a part connected to the second flow passages 46e, 46f. On the other hand, when the movement switching part 36 is positioned in the second position, the first flow passages 46a, 46b, 46c, and 46d are opened. The movement switching part 36 is moved by a driving part 22.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vacuum generating device, and more particularly to an ejector type vacuum generating device for generating a negative pressure state by passing compressed air.

[0002]

2. Description of the Related Art For example, a vacuum generator is incorporated in a vacuum suction device or the like. A conventional vacuum suction device is shown in FIG. In FIG. 7, 102 is an ejector type vacuum generator (for example, see Japanese Patent Publication No. 3-43479).
When compressed air is introduced from the pipe joint 104a, the pipe joint 104b
The inside becomes negative pressure. Reference numeral 106 denotes a suction pad, which is a pipe 1
It is connected to the pipe joint 104b via 14. When the inside of the pipe joint 104b has a negative pressure, the inside of the suction pad 106 also has a negative pressure, and a work (not shown) can be sucked on the lower surface of the suction pad 106. A valve device 108 controls the supply of compressed air to the vacuum generating device 102 by driving a spool valve provided inside with a solenoid valve 110. Compressed air is constantly supplied to the pipe joint 104c of the valve device 108 from a compressor (not shown). Compressed air is valve device 10
No. 8 pipe fitting 104d is supplied to the pipe fitting 104a of the vacuum generator 102 through the tube 112. Therefore,
By controlling the ON / OFF of the solenoid valve 110, the supply of compressed air from the valve device 108 to the vacuum generating device 102 is controlled, and as a result, the suction and release of the work by the suction pad 106 is controlled.

[0003]

However, the conventional vacuum suction device 100 has the following problems. Since the vacuum generator 102 and the valve device 108 are separate,
The occupying space required for attaching both is increased. In addition, it is necessary to carry out the mounting individually, and also to connect the two via the tube 112, which is troublesome because the number of working steps increases. In addition, there is a problem that the appearance after mounting is not good. Therefore, an object of the present invention is to provide a vacuum generator having both a vacuum (negative pressure) generating function and a control function.

[0004]

In order to solve the above problems, the present invention has the following constitution. That is, the main body,
A first port provided on the main body for introducing compressed air into the main body; a second port provided on the main body for introducing external air into the main body; A third port provided for discharging the air in the main body to the outside; a first flow path provided in the main body for connecting the first port and the third port; and in the main body A second flow path that is provided and has one end that communicates with the second port and the other end that communicates orthogonally with the first flow path; Of the first flow path, the first flow path is between the first port and the portion that communicates with the second flow path when the first flow path is in the first position. To move the movement switching unit, which is closed and opens the first flow path when it is in the second position, and the movement switching unit. Characterized by comprising a driving unit.

Further, a third flow path that connects the first port and the second port is provided in the main body portion, and the movement switching portion can be moved to the third position. When in the first position, the first flow path is closed between the first port and the portion communicating with the second flow path, and the third flow path is interrupted. When it is in the second position, the third flow path is closed in the middle, and when it is in the third position, the first flow path is connected to the first port. The second flow path may be closed midway while being closed between the portion communicating with the second flow path. Further, a part of the first flow path may be formed in the movement switching section, or the drive section may be integrally provided in the main body section.

[0006]

[Operation] The operation will be described. A vacuum generating function can be obtained by the configuration of the first port, the second port, the third port, the first flow path, and the second flow path provided on the main body. On the other hand, the movement switching section provided in the main body section can provide a control function for switching between generation and stop of vacuum (negative pressure) at the second port. Especially, the third
When the movement switching section is located at the third position, the air can be discharged from the second port by providing the flow passage of No. 3 and allowing the movement switching section to move to the third position.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT A preferred embodiment of the present invention will now be described in detail with reference to the accompanying drawings. FIG. 6 shows a vacuum generator 10 of this embodiment.
The front view of the vacuum adsorption device 12 using is shown. In FIG. 6, 14 is a suction pad, the lower surface of which is open.
The suction pad 14 is made of a flexible synthetic resin. By making the pressure inside the suction pad 14 negative, a work (not shown) can be sucked on the lower surface of the suction pad 14. A mounting portion 16 is provided on the suction pad 14 and a pipe joint 18a is disposed. The pipe joint 18a and the pipe joint 18b of the vacuum generator 10 are connected by a pipe 20, and external air can be sucked from the adsorption pad 14 to the vacuum generator 10 via the pipe 20.

Reference numeral 22 is a solenoid valve which is an example of a drive unit,
As will be described later in detail, the vacuum generator 10 is integrally attached. The solenoid valve 22 drives a movement switching unit arranged in the vacuum generator 10 to control suction and release of the work by the suction pad 14. It is a 24 muffler and regulates the exhaust noise when the compressed air is discharged from the vacuum generator 10. Reference numeral 26 is a tube, which is connected to a pipe joint 18c provided in the vacuum generator 10. Compressed air is constantly supplied from a compressor (not shown) to the vacuum generator 10 via a tube 26.

Next, the structure of the vacuum generator 10 used in the vacuum suction device 12 will be described. First, the vacuum generator 10 of the first embodiment will be described with reference to FIGS. 1 and 2. Reference numeral 28 denotes a main body portion, and the first port 30, the second port 32, and the third port 34 are opened on the outer wall surface. The pipe joint 18c is attached to the first port 30. Compressed air is introduced into the body portion 28 from the first port 30 through the tube 26.

A pipe joint 18b is attached to the second port 32. External air is introduced into the main body 28 from the second port 32. That is, the external air sucked from the suction pad 14 is supplied from the second port 32 to the main body 28.
Be introduced inside. The silencer 24 is attached to the third port 34. The compressed air introduced into the main body portion 28 from the first port 30 and the air introduced into the main body portion 28 from the second port 32 are discharged to the outside of the main body portion 28 from the third port 34. To muffle the noise generated by compressed air during discharge.

Reference numeral 36 is a spool, which is an example of a movement switching unit, and includes a first component member 38, a second component member 40, and a third component member 38.
The component member 42 and the fourth component member 44. The first component 38 is screwed to the second component 40.
Second component member 40, third component member 42, and third component member
The component member 42 and the fourth component member 44 are fitted and connected to each other. The spool 36 is arranged in the main body 28 and is movable between a first position (the position shown in FIG. 1) and a second position (the position shown in FIG. 2).

The spool 36 has a flow path 46a in the direction of the central axis.
Are formed. In the flow path 46a, the lower end portion of the second component member 40 is formed in a nozzle whose flow passage cross-sectional area gradually increases downward, and the upper end portion of the third component member 42 moves downward so as to cut off the flow passage. The diffuser has a gradually decreasing area. A flow path 46b is provided in the radial direction in the center of the second component member 40 that constitutes the spool 36. Third component member 4 that constitutes the spool 36
A flow path 46c is provided in the lower end of 2 in the radial direction.
A flow path 46f is provided in the upper end portion in the radial direction. The flow path 46d is formed in a plane circular shape, and the first port 3
0 communicates with the internal space in which the spool 36 is movable. The flow path 46e is formed on the outer periphery of the third component member 42. The lower end of the flow path 46e communicates with the second port 32, and the upper end communicates with the flow path 46f.

The flow paths 46d, 46b, and 46
a, in the flow path 46c, the first port 30 and the third port 3
A first flow path connecting 4 is configured. On the other hand, the flow path 46
e, the flow path 46f constitutes a second flow path having one end communicating with the second port 32 and the other end orthogonally communicating with the flow path 46a forming the first flow path. By adopting a configuration in which the flow path 46f is orthogonal to and communicates with the flow path 46a,
It is possible to obtain the ejector effect of sucking the air in the flow path 46f into the flow path 46a when the compressed air passes through the flow path 46a.

The solenoid valve 22, which is an example of a drive unit, is integrally incorporated in the main body unit 28. The solenoid valve 22 is the valve body 4
By opening and closing the flow path 46g at 8, the flow paths 46h, 4
The supply / discharge of air to / from the upper air chamber 50 or the lower air chamber 52 of the spool 36 is controlled via 6i. Reference numeral 54a is a coil spring, which is elastically mounted between the fourth component member 44 and the inner bottom surface of the main body portion 28 and constantly urges the spool 36 upward.

Next, the operation of the vacuum generator 10 of the first embodiment will be described. The state shown in FIG. 1 is a state in which the electromagnetic coil 56 of the solenoid valve 22 is not energized, and the valve body 48 is in a state in which the flow path 46g is closed. The spool 36 is at the uppermost position by the biasing force of the coil spring 54a, that is, the first position.
Is in the position. In this state, the compressed air sent from the first port 30 flows into the flow path 46d, but the flow path 46d
Since d has seal members 58a and 58b fitted around the outer periphery of the second component member 40, the flow of compressed air is hindered. The first flow passage is closed between the first port 30 and a portion that communicates with the second flow passage (a portion where the flow passage 46a and the flow passage 46f are orthogonal to each other). The compressed air that has entered the flow path 46i from the flow path 46d enters the lower air chamber 52 and urges the spool 36 upward, but the flow stops and the flow path 4
The flow of the compressed air entering the flow path 46g from 6d is stopped by the valve body 48. Further, since the compressed air is prevented from entering the flow path 46a, the ejector effect does not occur. Therefore, the suction pad 14 does not suck the work.

In the state of FIG. 1, when the electromagnetic coil 56 is energized, the valve body 48 moves downward against the urging force of the coil spring 54b and opens the flow path 46g. As a result, the compressed air stopped in the flow path 46g enters the upper air chamber 50 via the flow path 46h and moves the spool 36 downward against the biasing force of the coil spring 54a. At that time, compressed air is also introduced into the lower air chamber 52, but since the pressure receiving area of the upper air chamber 50 is set sufficiently larger than the pressure receiving area of the lower air chamber 52, the spool 36 can be moved downward. . FIG. 2 shows a state in which the spool 36 moves downward and is in the second position. When the spool 36 reaches the second position, the second
The large diameter portion 60 of the component member 40 comes into contact with the stopper portion 62 projecting from the inner wall of the main body portion 28, the downward movement of the spool 36 is restricted, and the spool 36 remains at that position.

In this state, since the flow paths 46b and 46d communicate with each other, the compressed air sent from the first port 30 enters the flow path 46a from the flow path 46d, and passes through the flow path 46c to the third flow path 46c. It is discharged from the port 34. Meanwhile, the flow path 4
Since the air in the flow path 46f is sucked into the flow path 46a by the ejector effect when the compressed air passes through the flow path 6a,
A negative pressure is created in the suction pad 14 through 6e, the second port 32, and the pipe 20. When the suction pad 14 has a negative pressure, the suction pad 14 can suck the work. In addition,
The air sucked from the second port 32 is the third air together with the compressed air.
Is discharged from the port 34.

When the energization of the electromagnetic coil 56 is stopped with the suction pad 14 adsorbing the work, the valve body 48 of the electromagnetic valve 22 again closes the flow path 46g by the urging force of the coil spring 54b. Then, since the supply of the compressed air to the upper air chamber 50 is stopped, the spool 36 is moved upward by the biasing force of the coil spring 54a and the pressure of the compressed air introduced into the lower air chamber 52, and the state shown in FIG. Return. As a result, the work sucked by the suction pad 14 is released.

Next, a second embodiment of the vacuum generator 10 will be described with reference to FIGS. In the first embodiment, the electromagnetic coil 5 is used to release the work from the suction pad 14.
Even if the power supply to 6 is stopped, in some cases, the suction pad 14
The inside may not return to positive pressure immediately. In the second embodiment, the vacuum generator 10 has a structure that can immediately release the suction pad 14 from the work. The same members as those in the first embodiment are designated by the same reference numerals as those in the second embodiment, and the description thereof will be omitted. In the first embodiment, the spool 36 has a first position where the flow of the compressed air is stopped in the middle of the first flow path, and the compressed air passes through the first flow path, and the suction pad 14 is passed through the second port 32. It was possible to stop at the second position where the inside became negative pressure. In the second embodiment, it is also possible to stop at the third position where compressed air can be derived from the suction pad 14 via the second port 32. In the second embodiment, for example, an electromagnetic valve 22 of a type in which two valve coils are individually driven by two electromagnetic coils is used. The solenoid valve 22 can selectively open and close the flow paths 46h and 46k.

First, FIG. 3 shows a state in which the spool 36 is in the first position. In this state, the solenoid valve 22 is not energized, and the flow paths 46h and 46k are closed. The spool 36 is located at an intermediate position in the main body 28, that is, the first position by the coil springs 54a and 54c having the same biasing force.

In this state, the compressed air sent from the first port 30 flows into the flow path 46d, but the flow path 46d.
Since there are seal members 58a and 58b fitted around the outer periphery of the second component 40, the flow of compressed air is hindered. The first flow passage is closed between the first port 30 and a portion that communicates with the second flow passage (a portion where the flow passage 46a and the flow passage 46f are orthogonal to each other). The compressed air that has entered the flow path 46j from the first port 30 is also prevented from flowing because there are seal members 58c and 58d fitted to the outer periphery of the third component member 42. Therefore, spool 3
When 6 is in the first position, the first flow path is blocked between the first port and the portion communicating with the second flow path,
In addition, the third flow path, which is composed of the flow path 46j and the space 66 between the seal members 58c and 58d and which can connect the first port 30 and the second port 32, is closed midway. Figure 3
In this state, since the compressed air does not enter the flow path 46a, the ejector effect does not occur. Therefore, the suction pad 14 does not suck the work.

Next, FIG. 4 shows the spool 36 in the second position. In this state, the solenoid valve 22 is energized,
The compressed air can flow in the flow path 46h and the flow path 46k cannot flow, and the spool 36 is at the lowest position, that is, the second position. When the spool 36 is at the second position, the compressed air that has entered the flow path 46j from the first port 30 has the seal members 58c and 58e and is blocked from flowing, so that the compressed air flows through the third flow path. It is in a blocked state halfway. However, since the flow path 46h is opened, the compressed air enters the upper air chamber 50 and moves the spool 36 downward against the biasing force of the coil spring 54a. Spool 3
When 6 moves down and reaches the second position, the second component 4
The large diameter portion 60a of 0 abuts on the stopper portion 62a protruding from the inner wall of the main body portion 28, the downward movement of the spool 36 is restricted, and the spool 36 remains at that position.

In this state, the flow paths 46b and 46d communicate with each other, so that the compressed air sent from the first port 30 enters the flow path 46a from the flow path 46d, and passes through the flow path 46c to the third flow path 46c. It is discharged from the port 34. Meanwhile, the flow path 4
Since the air in the flow path 46f is sucked into the flow path 46a by the ejector effect when the compressed air passes through the flow path 6a,
A negative pressure is created in the suction pad 14 through 6e, the second port 32, and the pipe 20. When the suction pad 14 has a negative pressure, the suction pad 14 can suck the work. In addition,
The air sucked from the second port 32 is the third air together with the compressed air.
Is discharged from the port 34.

Next, FIG. 5 shows a state in which the spool 36 is in the third position. In this state, the solenoid valve 22 is energized,
The compressed air can flow in the flow path 46k and the compressed air cannot flow in the flow path 46h, and the spool 36 is at the uppermost position.
That is, it is in the third position. When the spool 36 is at the third position, the first flow path is a portion where the seal members 58a and 58b connect the first port 30 and the second flow path (the flow path 46a and the flow path 46f are orthogonal to each other. Part) to be blocked. In the second flow path, the flow path 46 e is the seal member 58.
It is blocked midway by e. On the other hand, the third channel is
The space 66 and the second port 32 are in communication with each other.

The compressed air introduced from the first port 30 is
Since the flow path 46k is open, it enters the lower air chamber 52 and moves the spool 36 upward against the biasing force of the coil spring 54c. When the spool 36 moves upward and reaches the third position, the large diameter portion 60b of the fourth component member 44 abuts on the stopper portion 62b protruding from the inner wall of the main body portion 28, and the spool 36 is moved upward. It is regulated and stays in that position. In this state, since only the third flow path is in communication, the compressed air sent from the first port 30 is discharged from the suction pad 14 via the flow path 46j, the space 66, and the second port 32. It By this discharge, the suction pad 14
The work adsorbed on is immediately released.

When the energization of the solenoid valve 22 is stopped, the flow paths 46h and 46k are closed again, so that the upper air chamber 5
0, since the supply of compressed air to the lower air chamber 52 is stopped,
The spool 36 returns to the first position by the balanced biasing force of the coil springs 54a and 54c, and returns to the state of FIG. Although various preferred embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and it goes without saying that many modifications can be made without departing from the spirit of the invention. is there.

[0027]

When the vacuum generator according to the present invention is used,
First port, second port, third provided on the main body
The vacuum generating function can be obtained by the configuration of the port, the first flow path, and the second flow path. On the other hand, since the movement switching section provided in the main body section can obtain a control function for switching between generation (stopping) of vacuum (negative pressure) at the second port and stop thereof, the function of the conventional valve device also functions in the vacuum generator. Since it can be incorporated into the device, the space required for attaching the both can be small. It is also easy to install and does not require a connecting tube. It also looks good. In particular, when the structure of claim 2 is adopted, when the movement switching portion is at the third position, air can be led out from the second port. The work done can be released immediately.
When the configuration of claim 3 is adopted, a remarkable effect such as further downsizing of the device can be achieved.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a state in which a spool is at a first position in a first embodiment of a vacuum generator according to the present invention.

FIG. 2 is a cross-sectional view showing a state in which a spool is in a second position in the first embodiment.

FIG. 3 is a cross-sectional view showing a state in which the spool is at the first position in the second embodiment of the vacuum generating device according to the present invention.

FIG. 4 is a sectional view showing a state in which a spool is in a second position in the second embodiment.

FIG. 5 is a sectional view showing a state in which the spool is in the third position in the second embodiment.

FIG. 6 is a front view of a vacuum suction device using the vacuum generator according to the present invention.

FIG. 7 is a front view of a vacuum suction device using a conventional vacuum generator.

[Explanation of symbols]

 10 Vacuum Generator 22 Solenoid Valve 28 Main Body 30 Second Port 32 Second Port 34 Third Port 36 Spool 46a to 46k Flow Path

Claims (4)

[Claims] 1. A main body section, a first port provided in the main body section for introducing compressed air into the main body section, and a first port provided in the main body section for introducing external air into the main body section. 2 port, a third port provided in the main body portion for discharging air inside the main body portion to the outside, a third port provided in the main body portion, the first port and the third port
And a second flow path provided in the main body part, one end of which communicates with the second port and the other end of which communicates orthogonally with the first flow path. And disposed in the main body, movable between a first position and a second position, and in the first position,
Movement switching that closes the first flow path between the first port and a portion that communicates with the second flow path, and opens the first flow path when in the second position And a drive unit for moving the movement switching unit. 2. A third flow path that connects the first port and the second port is provided in the main body portion, and the movement switching portion is also movable to a third position. , In the first position, the first flow path to the first
And a portion that communicates with the second flow path, and the third flow path is blocked midway.
When it is in the position, the third flow path is closed midway, and when it is in the third position, the first flow path is divided into the first port and the second flow path. The vacuum generating apparatus according to claim 1, wherein the second flow path is closed midway while being closed between a portion that communicates with the second flow path. 3. The vacuum generator according to claim 1, wherein a part of the first flow path is formed in the movement switching section. 4. The vacuum generating apparatus according to claim 1, wherein the drive unit is integrally provided with the main body unit.