JP2001289167A - Silencer for vacuum pump - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a silencer for a vacuum pump efficiently reducing a noise provided in gas discharged from an exhaust port of the vacuum pump to discharge the gas to the outside air. SOLUTION: A regulating valve 60 is provided which widely/narrowly adjusts an opening amount of a first reducing port 54 connecting between two or more large rooms of a silencer making gas, discharged from an exhaust port of a vacuum pump, in accordance with a pressure or passing quantity of gas passing through the first reducing port or a passing amount of the gas. An opening amount of the first reducing port 54 is automatically adjusted to be matched with a pressure of gas passing through the first reducing port 54 or a passing amount of this gas. A moderated load is always applied to the gas passing through the first reducing port 54, so that a noise provided in the gas discharged from an exhaust port of the vacuum pump can be efficiently reduced while small suppressing a power loss of the vacuum pump.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for reducing noise generated when gas is discharged from a vacuum pump.
The present invention relates to a silencer for a vacuum pump.

[0002]

2. Description of the Related Art There are two types of noise, which are the cause of noise pollution generated when gas is discharged from a vacuum pump, such as the following expansion noise and backflow noise. The expansion sound is exhausted from the exhaust port of the vacuum pump operating at a relatively low vacuum pressure and a large flow rate.
This is an exhaust sound generated by a gas having a pressure higher than the atmospheric pressure. The expansion noise is noise generated by the gas discharged from the vacuum pump when the gas expands in the outside air. On the other hand, the backflow noise is noise generated when outside air flows backward into the vacuum pump from the exhaust port of the vacuum pump operating at a relatively high vacuum pressure and small flow rate and is sucked.

[0003] A muffler is used to reduce the expansion noise and backflow noise generated when gas is discharged from these vacuum pumps. The silencer generally has a structure in which two or more large rooms 51 are connected in series through a small-diameter first throttle port 53, as shown in FIG. A second throttle port 5 for communicating the large room with the outside air is provided in the last large room 51.
5 is open. According to this silencer, the gas discharged from the exhaust port of the vacuum pump is supplied to two or more large rooms 51.
And a second throttle port 5 for communicating between the large room 51 and the last large room 51 to the outside air.
5 can be passed sequentially to apply a load repeatedly to the gas. And the noise which the gas discharged from the vacuum pump has can be reduced. Then
The noise-reduced gas that has been reduced in noise can be discharged into the outside air through the second throttle port 55.

The exhaust port of a vacuum pump for obtaining a high vacuum pressure is provided with a check valve. The check valve prevents the outside air from flowing back into the vacuum pump during the pumping operation, thereby preventing a loss in the degree of achievement of the vacuum pressure of the vacuum pump. This check valve can also eliminate the above-mentioned backflow noise of the gas exhausted from the exhaust port of the vacuum pump operating at a high vacuum pressure. However, the operation sound of the check valve provided in the exhaust port of the vacuum pump is a relatively high-pitched, unpleasant metal contact sound that strikes the periphery of the exhaust port, and is a cause of noise pollution. Therefore, in the vacuum pump operated in this high vacuum pressure state, if the above-mentioned muffler is used, in addition to the expansion sound and the backflow sound of the gas discharged from the exhaust port of the vacuum pump, the above-mentioned check valve Operating noise can also be reduced. Then, the expansion sound, the backflow sound, and the operation sound of the check valve are reduced and the pollution-free gas is discharged to the second throttle port 5 of the silencer.
5, it can be discharged to the outside air.

[0005]

However, in the above silencer, the diameter of the first throttle port 53 through which the gas discharged from the discharge port of the vacuum pump passes is set to be constant. The load applied to the gas passing through the throttle port 53 has become constant. On the other hand, vacuum pumps
It is operated under various operating conditions to obtain a wide range of vacuum pressure from high vacuum pressure to low vacuum pressure. Vacuum pumps range from large to small. Therefore, the pressure of the gas discharged from the exhaust port of the vacuum pump varies widely from high pressure to low pressure, and the amount of gas discharged from the exhaust port of the vacuum pump varies widely from large to small amounts. Or Therefore, the expansion noise or backflow of a gas that changes in a wide range in the air pressure or the amount of the gas discharged from the exhaust port of a vacuum pump operated under various operating conditions or a vacuum pump from a large to a small size. When the noise and the operation sound of the check valve are reduced by using the above-described muffler having the first throttle port 53 having a constant diameter, the gas passing through the first throttle port 53 is added. The load becomes too large, so that an excessive load is applied from the silencer to the vacuum pump, causing a large power loss to the vacuum pump, or conversely, the load applied to the gas passing through the first throttle port 53 is too small. Therefore, the noise of the gas was not sufficiently reduced.

[0006] The present invention can solve such problems.
The opening amount of the first throttle port is adjusted to be large or small according to the pressure of the gas discharged from the exhaust port of a vacuum pump operated under various operating conditions or from a large to small vacuum pump or the amount of the discharged gas. A muffler that can always apply an appropriate load to the gas passing through the first throttle port without any excess or shortage. The noise of the gas discharged from the exhaust port of the vacuum pump is reduced by the power of the vacuum pump. It is an object of the present invention to provide a vacuum pump silencer (hereinafter, referred to as a silencer) that can efficiently reduce the loss while suppressing the loss.

[0007]

In order to achieve the above object, a muffler according to the present invention comprises a gas exhausting from an exhaust port of a vacuum pump, which is provided between two or more large rooms. Silence of a vacuum pump having a structure in which a first throttle port to be communicated and a second throttle port that communicates the last-stage large room to the outside air are sequentially passed to reduce the noise of the gas and discharge the air to the outside air. A regulating valve for adjusting the opening amount of the first throttle port to be narrow or wide in accordance with the pressure of a gas passing through the first throttle port or the amount of the gas passing therethrough. .

In this silencer, the opening amount of the first throttle opening communicating between the large rooms is made wider and narrower in accordance with the pressure of the gas passing through the first throttle opening or the amount of the gas passing therethrough. Can be adjusted. Therefore, when the pressure of the gas discharged from the exhaust port of the vacuum pump and passing through the first throttle port is high or the amount of gas passing therethrough is large, the opening amount of the first throttle port is adjusted accordingly. Can be expanded.
And it can prevent that the load added to the gas which passes through the 1st throttle opening becomes too large. Therefore, it is possible to prevent a large power loss from being generated in the vacuum pump due to an excessive load being applied to the vacuum pump from the muffler. Conversely, it is discharged from the exhaust port of the vacuum pump,
If the pressure of the gas passing through the first throttle port is low or if the amount of the gas passing therethrough is small, the first
The aperture of the aperture can be reduced. Then, it is possible to prevent the load applied to the gas passing through the first throttle opening from becoming too small. Then, it is possible to prevent the noise of the gas passing through the first throttle opening from being unable to be sufficiently reduced.

In the muffler according to the present invention, the regulating valve includes a valve main body that seals the first throttle port from a gas discharge side, and the valve main body moves in a direction away from the first throttle port and the first throttle port moves in a direction away from the first throttle port. It is preferable that the valve body comprises a support means for supporting the valve body so as to be movable in the direction of the throttle port and an urging means for applying an urging force for moving the valve body in the direction of the first throttle port to the valve body. .

[0010] In this silencer, when the pressure of the gas passing through the first throttle port is high or when the amount of the gas passing therethrough is large, a valve body for sealing the first throttle port, The valve body movably supported by the support means can be moved in a direction away from the first throttle port against the urging force of the urging means. Then, the opening amount of the first throttle port can be automatically expanded in accordance with the gas having the high air pressure or the gas having a large passage amount. Conversely, when the pressure of the gas passing through the first throttle port is low or the amount of gas passing therethrough is small, the valve body seals the first throttle port and is movably supported by the support means. The valve body can be moved in a direction to approach the first throttle port by using the urging force of the urging means. Then, the opening amount of the first throttle port can be automatically reduced in accordance with the gas having a low pressure or the gas having a small amount of passage.

Further, in the muffler according to the present invention, it is preferable that the muffler has a structure provided with an adjusting means for adjusting the urging force of the urging means for moving the valve body in the direction of the first throttle port. .

In this silencer, depending on whether the vacuum pump is large or small, the biasing force of the biasing means for moving the valve body movably supported by the support means toward the first throttle port is adjusted. By means, it can be adjusted strongly. Specifically, when the vacuum pump is large, the urging force of the urging means can be reduced by the adjusting means. Conversely, when the vacuum pump is small, the urging force of the urging means can be increased by the adjusting means. And, depending on whether the vacuum pump is large or small, the valve is opposed to the urging force of the urging means adjusted by the adjusting means in accordance with the amount of gas passing through the first throttle port which varies greatly from large to small. The main body can be appropriately moved in a direction away from the first throttle port, or conversely, can be appropriately moved in the first throttle port direction by using the urging force of the urging means adjusted by the adjusting means. When the vacuum pump is large, the opening amount of the first throttle port may be increased in accordance with the amount of gas discharged from the exhaust port of the vacuum pump and passing through the first throttle port. it can. Conversely, when the vacuum pump is small, the opening amount of the first throttle port is reduced in accordance with the amount of a small amount of gas discharged from the exhaust port of the vacuum pump and passing through the first throttle port. Can be.

Further, in the muffler of the present invention, it is preferable that a shock absorber is attached to a surface of the valve body which is pressed against the periphery of the opening of the first throttle port.

In this muffler, the valve body movably supported by the supporting means is moved by using the urging force of the urging means.
When moved in the direction of the first throttle port, the impact force of the valve body when it collides with the periphery of the opening of the first throttle port can be absorbed by the shock absorber attached to the surface of the valve body. Then, it is possible to reduce the impact sound that causes noise pollution when the valve body collides with the periphery of the opening of the first throttle port.

Further, in the muffler of the present invention, it is preferable that the large room has a structure in which a filter for removing dust contained in gas discharged from a vacuum pump is exchangeably housed.

In this silencer, the dust contained in the gas passing through the large room can be removed by passing the gas through the filter housed in the large room. When the filter is clogged with dust, the filter can be replaced with a new filter.

In the muffler of the present invention, the exhaust port of the vacuum pump is formed of an exhaust port and a pressure relief port, and the exhaust port is provided with a first check valve, and the pressure relief port is provided with a first check valve. And a second check valve.

In this silencer, the gas discharged from the exhaust hole of the vacuum pump by pushing the first check valve and the second check valve are removed.
The gas discharged from the pressure relief hole of the vacuum pump by displacing the check valve can flow into the large room at the front end of the muffler. Next, the gas is expanded through the first throttle port, one or more large chambers, and the second throttle port connected to the frontmost large room, and while the load is repeatedly applied, the expansion sound, the backflow sound and the first sound of the gas are generated. The operation noise of the check valve and the second check valve can be reduced and the air can be discharged into the outside air.

[0019]

1 and 2 show a preferred embodiment of a muffler according to the present invention. FIG. 1 is a schematic structural explanatory view of the muffler, and FIG. 2 is an enlarged structural explanatory view of a regulating valve portion thereof. . less than,
This silencer will be described.

In FIG. 1, reference numeral 10 denotes a rotary vacuum pump having vanes 16. The vacuum pump 10
A gas exhaust hole 12 is provided, and the exhaust hole 12 is provided with a first check valve 22. In addition, the illustrated vacuum pump 10 is provided with a pressure relief hole 14 for releasing gas compressed to a pressure higher than the atmospheric pressure in the vacuum pump 10 into the outside air to reduce power loss of the vacuum pump 10. The pressure relief hole 14 has a second check valve 24
Is provided. The exhaust hole 12 and the pressure relief hole 14
Constitutes a gas exhaust port of the vacuum pump.

The silencer 50 shown is used by being mounted on the upper end of such a vacuum pump 10. In the silencer 50, the gas discharged to the outside of the vacuum pump 10 by pushing the first check valve 22 from the exhaust hole 12 of the vacuum pump, or the second check valve 24 from the pressure release hole 14 of the same vacuum pump.
Gas discharged from the vacuum pump 10
The muffler 50 is configured to be able to flow into the first room 52 of the same large room together. Next, the gas can be discharged into the outside air through the first throttle port 54 connected to the first room 52 in the muffler 50, the second room 56 of the large room, and the second throttle port 58. Is configured. At that time, the first throttle port 54 and the second
A load is applied to the gas passing through the throttle port 58 to reduce the exhaust noise of the gas and the operation noise of the first check valve 22 and the second check valve 24.

The structure of the above-described silencer is the same as that of the conventional silencer, but the silencer 50 shown in FIG.
Of the gas passing through the first throttle port 54 or the amount of the gas passing through the adjusting valve 60 for adjusting the opening amount of the opening and closing of the opening and closing of the gas.
Is provided. As shown in FIG. 2, the adjustment valve 60 includes a valve main body 62 that seals the first throttle port 54 from the gas supply side, and a valve main body that moves in a direction away from the first throttle port 54, A support means 64 for supporting the valve body 62 movably in the direction of the port 54 and an urging force for moving the valve body 62 movably supported by the support means in the direction of the first throttle port 54 to the valve body 62. And an urging means 66 for applying. The support means 64 is composed of a support rod 642 projecting from the peripheral wall of the second chamber 56 to the inside thereof, and the valve body 62 is slidably supported around the support rod 642. The urging means 66 is a compression coil spring 662 loosely fitted around the support rod 642,
42, the compression coil spring 6 sandwiched between the inside of the flange 644 protruding in the middle and the valve body 62 opposed thereto.
62.

The silencer 50 shown in FIGS. 1 and 2 is constructed as described above. In this silencer 50, the silencer 50 is discharged from the exhaust hole 12 and the pressure release hole 14 of the vacuum pump, The opening amount of the first throttle port 54 communicating between the first chamber 52 and the second chamber 56 is adjusted according to the pressure of the gas passing through the throttle port 54 or the amount of the gas passing therethrough.
With 0, it can be adjusted widely. Specifically, the first throttle port 5
The valve main body 62 slidably supported around the support rod 642 is pressed against the urging force of the compression coil spring 662 in accordance with the level of the pressure of the gas passing through 4 or the amount of the gas passing therethrough. It is automatically moved in the direction away from the first throttle port 54, or conversely, the first
It can be automatically moved in the direction of the aperture 54. When the pressure of the gas discharged from the exhaust port of the vacuum pump 10 and passing through the first throttle port 54 is high or the amount of the gas passing through is large, the first throttle port 5 is adjusted accordingly.
By increasing the opening amount of 4, the load applied to the gas passing through the first throttle port 54 can be prevented from becoming too large. Therefore, it is possible to prevent the excessive load from being applied to the vacuum pump 10 from the muffler 50 and causing a large power loss in the vacuum pump 10. Conversely, when the pressure of the gas discharged from the exhaust port of the vacuum pump 10 and passing through the first throttle port 54 is low or the amount of gas passing therethrough is small, the first throttle port 54 is adjusted accordingly. By narrowing the opening amount, it is possible to prevent the load applied to the gas passing through the first throttle port 54 from becoming too small. Then, it is possible to prevent the expansion noise and the backflow noise of the gas passing through the first throttle port 54 and the operation noise of the first check valve 22 and the second check valve 24 from being unable to be sufficiently reduced. it can.

In this silencer, depending on whether the vacuum pump 10 is large or small, the valve body 62 is connected to the first throttle port 54.
It is preferable to provide an adjusting means 90 for adjusting the urging force of the urging means 66 for moving in the direction. And vacuum pump 1
In accordance with the amount of gas passing through the first throttle port 54, which differs greatly depending on whether 0 is large or small, the supporting means 64
The urging force of the urging means 66 for moving the valve body 62 movably supported in the direction of the first throttle port 54 is adjusted by the adjusting means 90.
It is good to be able to adjust strongly. For example, as shown in FIG. 2, the adjusting means 90 uses a double nut mechanism to move the flange 644 in the middle of the support rod 642 toward the valve body 62 or away from the valve body 62, It is preferable that the biasing force of the compression coil spring 662 that pushes the compression spring 62 toward the first throttle port 54 can be adjusted to be strong or weak. When the vacuum pump 10 is large and the amount of gas passing through the first throttle port 54 is large, the urging force of the urging means 66 is reduced by the adjusting means 90 so that the valve body 62 and the first throttle It is preferable that the gap between the mouth 54 can be widened. Conversely, when the vacuum pump 10 is small and the amount of gas passing through the first throttle port 54 is small, the urging force of the urging means 66 is increased by the adjusting means 90 so that the valve body 62 and the first It is preferable that the gap between the aperture 54 and the aperture 54 can be narrowed. Then, depending on whether the vacuum pump 10 is large or small, the urging force of the urging means 66 adjusted by the adjusting means 90 is adjusted in accordance with the amount of gas passing from the large amount to the small amount passing through the first throttle port 52. Then, the valve body 62 is appropriately moved in a direction away from the first throttle port 54, or conversely, the first throttle port 5 is moved by using the urging force of the urging means 66 adjusted by the adjusting means 90.
It is preferable to be able to move the distance appropriately in four directions. Then, it is preferable that the opening amount of the first throttle port 54 can be adjusted in a wide and narrow manner in accordance with the amount of gas passing through the first throttle port 54, which is largely different from the above-mentioned large to small quantity.

Further, as shown in FIG. 2, a shock absorber 70 such as a felt plate may be attached to the surface of the valve body 62 which is pressed against the periphery of the opening of the first throttle port 54. When the valve body 62 movably supported by the support means is moved in the direction of the first throttle port 54 by using the urging force of the urging means 66, the periphery of the opening of the first throttle port 54. It is preferable that the impact force of the valve main body 62 when it collides with the shock absorber 70 can be absorbed by the shock absorber 70. Then, it is preferable to reduce the impact sound that causes noise pollution when the valve main body 62 collides with the periphery of the opening of the first throttle port 54.

The first room 52 of the large room, etc.
As shown in (1), a filter 80 for removing dust contained in the gas discharged from the vacuum pump 10 may be exchangeably housed. Then, dust such as powder discharged from the vane 16 made of carbon of the vacuum pump, for example, contained in the gas passing through the large room can be passed through the filter 80 housed in the large room and removed by the filter 80. It is good to do. Then, it is preferable that a clean, non-polluting gas can be discharged from the second throttle port 58 to the outside air. When the filter 80 is clogged with dust, the filter 80 may be replaced with a new filter.

The muffler 50 has a structure in which one or more large rooms such as a third room are added to the first room 52 and the second room 56, and two or more large rooms are provided between the large rooms. First
A structure in which communication is made through the aperture 54 may be adopted. Then, a load may be applied to the gas passing through the two or more first throttle ports 54 twice or more. Then, the noise of the gas may be significantly reduced.

If the amount of dust contained in the gas discharged from the vacuum pump 10 is small and the dust does not cause pollution, a filter 8 for removing dust is installed in the large room.
0 does not have to be accommodated.

When a vacuum pump having a certain size is used, the adjusting means 90 for adjusting the urging force of the urging means 66 is not necessary.

The silencer of the present invention can also be used for a silencer of a vacuum pump in which the gas exhaust port is only the exhaust hole 12 and the pressure relief hole 14 is not provided. Also in this case, the muffler of the present invention can easily and quickly reduce the expansion noise and backflow noise of the gas discharged from the exhaust hole 12 of the vacuum pump and the operation noise of the first check valve 12. it can. Further, the silencer of the present invention can be used for various vacuum pumps such as a reciprocating type. Also in that case, the noise of the gas discharged from the exhaust port of the reciprocating vacuum pump can be easily and accurately reduced by the silencer of the present invention.

[0031]

As described above, according to the silencer of the present invention, the exhaust gas is discharged from the exhaust ports of the vacuum pumps operated under various operating conditions and the vacuum pumps from large to small.
The opening amount of the first throttle port can be adjusted to be large or small according to the pressure of the gas passing through the first throttle port or the amount of the gas passing therethrough. Then, an appropriate load is always applied to the gas passing through the first throttle port without excess or shortage, and the noise of the gas discharged from the vacuum pump is efficiently reduced while suppressing the power loss of the vacuum pump. be able to.

[Brief description of the drawings]

FIG. 1 is a schematic structural explanatory view of a muffler of the present invention.

FIG. 2 is an explanatory view of an enlarged structure of a regulating valve portion of the muffler of the present invention.

FIG. 3 is a schematic structural explanatory view of a conventional silencer.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Vacuum pump 12 Exhaust hole 14 Pressure relief hole 16 Vane 22 First check valve 24 Second check valve 50 Silencer 52 First room 54 First throttle 56 Second room 58 Second throttle 60 Control valve 62 Valve Main body 64 Supporting means 66 Urging means 70 Shock absorber 80 Filter 90 Adjusting means

Continuation of the front page (72) Inventor Tetsuya Kobayashi 246 Koyuki Yukitaka, Suzaka-shi, Nagano F-term in Orion Machinery Co., Ltd. (reference) 3H003 AA05 AC01 BA04 3H029 AA05 AB06 BB21 BB35 BB36 CC13 CC15 CC23 CC25 CC28 CC43

Claims (6)

[Claims] 1. A first system for communicating gas discharged from an exhaust port of a vacuum pump between two or more large rooms and between the large rooms.
The second to connect the throttle port and the last large room to the outside air
A muffler for the vacuum pump having a structure in which the gas passes through the throttle port in order to reduce the noise of the gas and discharge the gas to the outside air, wherein the opening amount of the first throttle port is passed through the first throttle port. A silencer for a vacuum pump, comprising an adjusting valve for adjusting the width of the gas in accordance with the pressure of the gas to be discharged or the amount of the gas passing therethrough. 2. The valve according to claim 1, wherein the regulating valve seals the first throttle port from a gas supply side, and the valve body moves in a direction away from the first throttle port or in a direction toward the first throttle port. 2. A muffler for a vacuum pump according to claim 1, comprising: support means for supporting the valve body in a movable manner; and urging means for applying an urging force to the valve body to move the valve body toward the first throttle port. 3. The muffler for a vacuum pump according to claim 1, further comprising adjusting means for adjusting the urging force of the urging means for moving the valve body toward the first throttle port. 4. A shock absorber is attached to a surface of a valve body pressed against the periphery of the opening of the first throttle port.
4. The muffler for a vacuum pump according to 2 or 3. 5. The muffler for a vacuum pump according to claim 1, wherein a filter for removing dust contained in gas discharged from the vacuum pump is exchangeably accommodated in the large room. 6. An exhaust port of the vacuum pump is formed of an exhaust hole and a pressure relief hole, the exhaust hole is provided with a first check valve, and the pressure relief hole is provided with a second check valve. The muffler for a vacuum pump according to claim 1, 2, 3, 4, or 5.