JP7350398B2 - Vacuum exhaust device with silencer - Google Patents

Description

The present invention relates to a vacuum evacuation device with a silencer equipped with a positive displacement dry vacuum pump. The present invention also relates to a vacuum evacuation device with a silencer that includes a mechanical booster pump and a positive displacement dry vacuum pump.

In cases where a clean vacuum environment is required, such as in reaction chambers of semiconductor manufacturing equipment, a vacuum evacuation system consisting of a mechanical booster pump and a positive displacement dry vacuum pump connected in series is used. . For example, a unit type vacuum evacuation device is used in which a mechanical booster pump and a dry vacuum pump are placed horizontally in the top and bottom of the device housing. In such vacuum evacuation equipment, a silencer is installed to reduce the noise generated when gas is exhausted from the intermediate stage outlet and final stage outlet of the dry vacuum pump connected to the most downstream side in the exhaust direction. It will be done.

Here, a silencer-equipped vacuum evacuation device (dry vacuum pump device) including a multistage dry vacuum pump has been proposed, for example, in Patent Documents 1 and 2. In these documents, a silencer is attached to the bottom side of a horizontally placed multistage dry vacuum pump to reduce the noise of gas discharged from the final stage outlet and the intermediate stage outlet.

In addition, in a unit-type vacuum exhaust system with a silencer that includes a mechanical booster pump and a multi-stage dry vacuum pump built into the equipment casing, the silencer is placed in the installation space secured inside the equipment casing. . When installation space cannot be secured inside, a silencer is attached to the outer surface of the device housing.

Japanese Patent Application Publication No. 2011-226368 Japanese Patent Application Publication No. 2011-226370

In a vacuum exhaust device with a silencer, since it is necessary to install a silencer, a large amount of installation space is required. Furthermore, even in the case of a unit-type vacuum evacuation device, it is necessary to install a silencer inside or outside the device housing, which requires a correspondingly large amount of installation space. It is desirable to assemble a silencer to a dry vacuum pump without requiring a large amount of installation space.

An object of the present invention is to provide a vacuum pumping device with a silencer in which a silencer is assembled in a manner that suppresses an increase in installation space.

In order to solve the above problems, the vacuum evacuation device of the present invention has the following features:
Positive displacement dry vacuum pump,
a silencer that reduces noise when exhaust gas is discharged from the dry vacuum pump;
It has
The dry vacuum pump is
a silencer installation surface on which the silencer is installed in the pump casing of the dry vacuum pump;
a pump intake port and a pump exhaust port that are open to the silencer installation surface;
It is equipped with
The silencer is
an intake passage communicating with the pump intake port;
a plurality of sound-deadening compartments;
an exhaust passage communicating with the pump exhaust port and allowing the exhaust to flow sequentially through each of the silencing compartments;
a silencer case in which the intake passage, the silencing compartment, and the exhaust passage are formed;
a first case outer surface portion of the silencer case facing the silencer installation surface;
an intake passage outlet of the intake passage that opens at a portion of the first case outer surface facing the pump intake port;
an exhaust passage entrance of the exhaust passage opening at a portion of the first case outer surface facing the pump exhaust port;
an intake passage inlet of the intake passage and an exhaust passage outlet of the exhaust passage, which are open to a case outer surface portion of the silencer case that is different from the first case outer surface portion;
It is characterized by having the following.

A dry vacuum pump is placed horizontally, for example, so that the central axis of the pump rotor is horizontal. In this case, the silencer installation surface is formed on the upper surface portion of the pump casing. Further, the silencer case includes a case lower surface portion which is the first case outer surface portion, a case upper surface portion, and a case outer peripheral side surface portion.The case lower surface portion is the first case outer surface portion, and the case upper surface portion The intake passage outlet of the intake passage is open, and the exhaust passage outlet of the exhaust passage is opened at the upper surface portion of the case or the outer peripheral side surface portion of the case.

In the vacuum evacuation device of the present invention, a silencer is installed on the intake side of the dry vacuum pump, and the silencer is equipped with an exhaust passage that takes in the exhaust gas discharged from the dry vacuum pump, and a pump intake port of the dry vacuum pump. It also has an intake passage that communicates with the. Since the intake passage inlet of the intake passage is open in the silencer case of the silencer attached to the dry vacuum pump, suction gas is supplied from the outside to the dry vacuum pump via the intake passage of the silencer. Since the intake passage is integrated with the silencer, there is no need to route the intake piping separately, and the installation space for the intake piping is also small, making it possible to reduce the size of vacuum exhaust equipment equipped with a dry vacuum pump equipped with a silencer. It is advantageous for miniaturization and downsizing.

If a silencer is installed on the top of a dry vacuum pump that is placed horizontally, and the intake passage inlet and exhaust passage outlet are located on the top of the silencer case, the piping connection work when installing the vacuum exhaust system must be done. This can be done from the top of the device. Therefore, there is an advantage that installation work including piping work becomes easier.

Here, when constructing a vacuum evacuation apparatus having a configuration in which a mechanical booster pump is connected to the front side of a dry vacuum pump, a silencer may be disposed between these pumps. The silencer is integrally formed with an intake passage that communicates with the intake side of the dry vacuum pump on the downstream side, so the exhaust from the mechanical booster pump is transferred to the dry vacuum pump on the downstream side via this intake passage. can be sent.

In this case, a configuration may be adopted in which a joint pipe attached to connect the pump exhaust port of the mechanical booster pump and the pump intake port of the dry vacuum pump is integrated with the silencer. That is, a joint pipe may be integrally formed in the silencer case as the above-mentioned intake passage.

In this way, the silencer can be placed using the installation space of the joint pipe that is attached to connect the pump exhaust port of the mechanical booster pump and the pump intake port of the dry vacuum pump. Since there is no need to separately secure an installation space for the silencer, it is advantageous for making the vacuum exhaust device smaller and more compact, and reducing manufacturing costs.

In this case, the silencer case can have a function as a mounting flange for connecting the joint pipe to the pump casings of both pumps. This makes it possible to reduce the number of parts for piping connections, making it possible to further downsize and compact the vacuum evacuation device and reduce manufacturing costs.

Next, since the silencer is attached to the dry vacuum pump or placed between the mechanical booster pump and the dry vacuum pump, the silencer is heated by heat radiation and heat transfer from these pumps. When exhausting condensable gas (solvent, gas, etc.), if the saturated water vapor pressure is exceeded, the condensable gas will condense while passing through the silencer. According to the present invention, since the silencer is heated by heat generated from the pump, condensation of gas inside the silencer can be suppressed without providing a heating means such as a heater. In particular, when the silencer is disposed between the dry vacuum pump and the mechanical booster pump, the silencer is heated from both sides, so that gas condensation inside the silencer can be suppressed more reliably.

In the present invention, as a material for the silencer case, a material having higher thermal conductivity than the material for the pump casing, for example, a metal material such as aluminum or aluminum alloy, can be used. In this case, the silencer case functions as a heat radiator that efficiently absorbs the heat of the pump and releases it to the outside, so that the pump can be prevented from becoming overheated.

In the present invention, the silencer includes, as the noise-muffling compartment, a compartment with an expansion chamber structure arranged on the upstream side in the flow direction of the exhaust gas, and a compartment with a sound absorption structure arranged on the downstream side. Can be used. It is also possible to use a silencer with a resonantly structured compartment as the muffling compartment.

Furthermore, in order to make the vacuum evacuation device smaller and more compact, it is desirable to integrate a drain mechanism into the silencer for discharging condensed water generated in the silencing compartment to the outside. Similarly, it is desirable to integrally incorporate into the silencer a gas ballast mechanism including a ballast gas passage and a non-return valve for guiding ballast gas from the outside to the ballast gas inlet of the dry vacuum pump.

(a) is a schematic configuration diagram showing a unit type vacuum evacuation device according to Embodiment 1 to which the present invention is applied, (b) is a plan view showing a silencer, and (c) is a front view thereof. . (a) is a plan view showing the internal structure of the silencer, (b) is a schematic sectional view taken along the line bb', and (c) is a perspective view showing the case body of the silencer. (a) is an explanatory diagram showing a vacuum evacuation device according to Embodiment 2, (b) is a plan view showing a silencer, and (c) is a front view thereof. (a) is a plan view showing the internal structure of the silencer, (b) is a schematic cross-sectional view of a portion taken along line BB', and (c) is a portion in which a gas ballast mechanism is incorporated. It is a partial cross-sectional view, and (d) is a perspective view which shows the case main body of a silencer.

Embodiments to which the present invention is applied will be described below with reference to the drawings. Each embodiment described below is an example of the present invention, and the present invention is not intended to be limited to the configurations of these embodiments.

(Embodiment 1)
FIG. 1(a) is a schematic configuration diagram showing a unit type vacuum evacuation device according to Embodiment 1, and FIG. 1(b) and FIG. 1(c) are a plan view and a front view showing a silencer. The vacuum evacuation device 1 includes a device casing 2, a mechanical booster pump 3 built into the device casing 2, a positive displacement dry vacuum pump 4, and an exhaust port 31 of the mechanical booster pump 3 (previous pump exhaust A joint pipe 5 (flange) that connects the dry vacuum pump 4 with the intake port 41 (back-stage pump intake port) of the dry vacuum pump 4, and a silencer 6 in which the joint pipe 5 is incorporated and integrated. There is. The silencer 6 is connected to the exhaust port 42 (second-stage pump exhaust port) of the dry vacuum pump 4.

The device housing 2 has a rectangular parallelepiped shape, and a displacement dry vacuum pump 4 is disposed on the bottom side thereof in a horizontal position with the center axis of a pump rotor (not shown) being horizontal. has been done. Above the dry vacuum pump 4, a mechanical booster pump 3 is also placed horizontally. The exhaust port 31 of the mechanical booster pump 3 opens downward. The inlet port 41 of the dry vacuum pump 4 opens upward and coaxially faces the exhaust port 31 on the front stage side at a predetermined interval. The exhaust port 31 on the front side and the intake port 41 on the rear side are connected by a joint pipe 5 that is integrated into the silencer 6. The components of the silencer 6 are arranged to surround the outer periphery of the joint pipe 5 between the exhaust port 31 of the mechanical booster pump 3 and the intake port 41 of the dry vacuum pump 4.

For example, the evacuation device 1 is used to evacuate a vacuum chamber or the like of semiconductor manufacturing equipment (not shown). Exhaust air from a vacuum chamber, etc. is sucked through an L-shaped piping joint 8 attached to the top surface of the device housing 2 through piping (not shown), and sequentially through a mechanical booster pump 3 and a dry vacuum pump 4. . Exhaust gas from the dry vacuum pump 4 is discharged via a silencer 6 from an exhaust outlet pipe 9 that opens on the side surface of the device housing 2.

The silencer case 50 of the silencer 6 is composed of a case body 60 that opens upward, and a connecting flange 70 that is a case lid to which this case body 60 is attached, and includes a case lower surface portion 50a and a case upper surface portion 50b. and a case outer circumferential side portion 50c.

The connecting flange 70 is a plate member with a rectangular outline, and closes the upper end opening of the case body 60. In addition, the four corners of the outer peripheral edge of the connecting flange 70 that protrudes outward from the upper end opening of the case body 60 are attached to the support bracket 43 on the lower side of the dry vacuum pump 4 by the fastening bolts 11. Fastened and fixed. The mechanical booster pump 3 is mounted horizontally on the connecting flange 70 and is fastened and fixed to the connecting flange 70.

In this example, the connecting flange 70 is fastened and fixed to the support bracket 43 with the vibration isolating rubber 12 (vibration absorbing material) in between. An upper end opening 71 that communicates with the upper end of the joint pipe 5 is opened in the case upper surface portion 50b of the connecting flange 70. An outer circumferential portion of the upper end opening 71 is fastened and fixed to an outer circumferential portion of the exhaust port 31 in the pump housing of the upper mechanical booster pump 3 using a fastening bolt (not shown).

The connecting flange 70 to which the case body 60 is attached is fastened and fixed to the upper and lower mechanical booster pumps 3 and the dry vacuum pump 4. As a result, the upper end opening 71 of the joint pipe 5 is coaxially connected to the exhaust port 31 of the mechanical booster pump 3, and the lower end opening 52 of the joint pipe 5 is coaxially connected to the intake port 41 of the dry vacuum pump 4. is formed.

A case body 60 of the silencer case, in which the cylindrical joint pipe 5 is integrally formed, includes a bottom wall portion 61 and an outer peripheral wall portion 62 surrounding the joint pipe 5. The upper edge portion of the outer peripheral wall portion 62 functions as a flange, and this portion is attached to the connecting flange 70 with fastening bolts 13. An exhaust passage inlet 63 for taking in exhaust from the dry vacuum pump 4 is opened in the case lower surface portion 50a, which is the bottom surface of the bottom wall portion 61 of the case body 60. The upper part of the pump housing of the lower dry vacuum pump 4 is a silencer installation surface, and an exhaust port 42 is opened here. When the silencer 6 is attached, the exhaust passage inlet 63 is connected to the exhaust port 42.

In this example, the joint pipe 5 and the case body 60, which are formed as a single component, are made of a material having higher thermal conductivity than the material of the pump housings of the upper and lower mechanical booster pumps 3 and the dry vacuum pump 4. . For example, it is formed from aluminum, aluminum alloy, or the like.

FIG. 2(a) is a plan view showing the internal configuration of the silencer 6, with the connecting flange 70 omitted. FIG. 2(b) is a schematic cross-sectional view of the portion taken along line bb', and also shows the connecting flange 70. FIG. 2(c) is a perspective view showing the case body 60 of the silencer case.

Referring also to FIG. 2, the silencer 6 includes a plurality of noise-muffling compartments inside. In this example, four silencing compartments 64 to 67 are arranged between the case body 60 and the connecting flange 70 so as to surround the joint pipe 5. Further, as shown by the arrows in FIGS. 2(a) and 2(b), the exhaust gas of the dry vacuum pump 4 introduced from the exhaust passage inlet 63 is sequentially passed through the four noise-reducing compartments 64 to 67. An exhaust passage 68 is arranged. In this example, from the upstream side to the downstream side in the flow direction of exhaust gas, a first compartment 64 with an expansion chamber structure, a second compartment 65 with an expansion chamber structure, a third compartment 66 with a sound absorbing structure, and an expansion chamber structure. The fourth compartment 67 is formed in this order. As shown in FIG. 2(b), the heights of the bottom surfaces of the first to fourth compartments 64 to 67 for noise reduction are set to become lower in stages toward the downstream side in the flow direction of the exhaust gas. ing.

An exhaust passage outlet 68a of the exhaust passage 68 is opened in the case outer peripheral side surface portion 50c of the case body 60. Exhaust gas is discharged to the outside from the fourth compartment 67 at the final stage via the exhaust passage outlet 68a of the exhaust passage 68. Inside the third compartment 66 having a sound-absorbing structure, an exhaust gas flow pipe 66a made of a porous material such as punched metal is disposed, and a sound-absorbing material 66b is filled to surround the outer periphery of the exhaust flow pipe 66a. It is also possible to provide a resonance type muffling chamber as the muffling compartment.

The case body 60 of the silencer 6 is integrally formed with a drain mechanism (not shown) for discharging condensed water generated inside to the outside, and a drain plug 14 is attached to the drain port of the drain mechanism (not shown). ing. The case body 60 also incorporates a gas ballast mechanism (not shown). A ballast gas passage 15 is open in the case body 60, from which ballast gas is supplied to the dry vacuum pump 4 via piping (not shown).

In the unit type vacuum evacuation device 1 of this example configured in this way, we focused on the space surrounding the outer periphery of the joint pipe 5 that connects the mechanical booster pump 3 and the dry vacuum pump 4 that are arranged above and below. This space is used as an installation space for the silencer 6. Moreover, the joint pipe 5 is incorporated into the silencer 6 and is integrated. Thereby, there is no need to separately secure installation space for the silencer 6 inside the device housing 2, which is advantageous in making the vacuum evacuation device 1 smaller and more compact. Moreover, since the joint pipe 5 is integrated into the silencer 6, these installation operations can be performed efficiently and with a small number of parts.

Furthermore, the silencer 6 is sandwiched between the mechanical booster pump 3 and the dry vacuum pump 4 from above and below. Since the silencer 6 is heated by the heat generated by these pumps 3 and 4, condensed water or the like can be prevented from accumulating inside the silencer 6 when a condensable gas is caused to flow without heating using a heater. In particular, in this example, the case body 60 of the silencer 6 and the joint pipe 5 are made of a metal material such as aluminum, which has higher thermal conductivity than the material of the pump housings of the upper and lower pumps 3 and 4. Therefore, the silencer 6 can efficiently absorb heat from the upper and lower pumps 3 and 4, and functions as a heat radiating section for discharging heat from the upper and lower pumps 3 and 4 to the outside.

In addition, the silencer 6 includes a drain mechanism and a gas ballast mechanism. This is advantageous in making the evacuation device 1 smaller and more compact, and in reducing manufacturing costs, compared to the case where parts such as drain piping and ballast gas communication pipes are separately arranged.

Note that the dry vacuum pump 4 is generally a multistage dry vacuum pump, and exhaust gas is discharged not only from the final stage exhaust port but also from the intermediate stage exhaust port. In this case, the exhaust gas discharged from the final stage exhaust port and the intermediate stage exhaust port is taken into the internal exhaust passage 68 from the exhaust passage entrance 63 of the silencer 6.

(Embodiment 2)
FIG. 3(a) is an explanatory diagram showing a vacuum evacuation device (dry vacuum pump device) according to Embodiment 2, FIG. 3(b) is a plan view showing a silencer, and FIG. 3(c) is a front view thereof. It is a diagram. The evacuation device 100 (dry vacuum pump device) includes a positive displacement multistage dry vacuum pump 110 and a silencer 130 connected to an exhaust port of the multistage dry vacuum pump 110. The multi-stage dry vacuum pump 110 is mounted horizontally on an apparatus stand 150, and a driving motor 160 is coaxially attached to the multi-stage dry vacuum pump 110.

The silencer 130 includes a silencer case 131 having an overall flat rectangular parallelepiped shape, and the silencer case 131 is formed with a case lower surface portion 131a, a case upper surface portion 131b, and a case outer peripheral side surface portion 131c. In this example, the silencer case 131 includes a case body 132 and a case lid 133 attached to the upper end of the case body 132. An intake pipe 134 is attached to one end of the case top surface portion 131b, and an exhaust pipe 135 is attached to the other end. Silencer 130 is mounted horizontally on top of multi-stage dry vacuum pump 110. Gas is sucked into the multistage dry vacuum pump 110 via an intake pipe 134 attached to the top surface of the silencer 130. Exhaust gas from the multi-stage dry vacuum pump 110 passes through the inside of the silencer 130 and is exhausted through an exhaust pipe 135 attached to the top surface thereof.

FIG. 4A is a plan view showing the internal structure of the silencer 130, with the case lid 133 omitted. FIG. 4(b) is a schematic cross-sectional view taken along line BB' in FIG. 4(a), and also shows the case lid 133. FIG. 4(c) is a partial sectional view of a portion in which the gas ballast mechanism is incorporated, and FIG. 4(d) is a perspective view showing the case body 132 of the silencer case 131.

Explaining with reference to these figures, the multistage dry vacuum pump 110 includes a cylindrical pump casing 111, and a silencer installation surface 112 is formed at the upper end portion of the outer peripheral surface of the pump casing 111. . This silencer installation surface 112 has an intake port and an exhaust port open therein. In this example, the intake port 113 communicates with the first stage compression chamber of the multistage dry vacuum pump 110. Further, as exhaust ports, a final stage exhaust port 116 that communicates with the compression chamber of the final stage and intermediate stage exhaust ports 114 and 115 that communicate with the compression chambers of a plurality of intermediate stages between the first stage and the final stage are opened. ing. In FIG. 4, two intermediate stage exhaust ports 114 and 115 are shown, but there may be one, or there may be three or more.

As described above, the silencer 130 includes a silencer case 131 that includes a case body 132 and a case lid 133. Inside the silencer case 131, an intake passage 136, an exhaust passage 137, and a plurality of silencing compartments are formed.

The intake passage 136 will be explained. A case lower surface portion 131a of the silencer case 131 is a portion that faces the silencer installation surface 112 from above. An intake passage outlet 136b, which is a lower end opening of the intake passage 136, is opened in the case lower surface portion 131a at a portion corresponding to the intake port 113. An intake passage inlet 136a, which is an opening at the upper end of the intake passage 136, communicates with an intake pipe 134 attached to a case upper surface portion 131b of the silencer case 131. Gas is sucked into the intake port 113 of the multistage dry vacuum pump 110 from an intake pipe 134 attached to the case upper surface portion 131b of the silencer 130 via an intake passage 136.

The sound deadening compartment will be explained. Inside the silencer case 131, a plurality of silencing compartments are formed between the case body 132 and the case lid 133. In this example, a first compartment 141 for muffling, a second compartment 142 for muffling, and a third compartment 143 for muffling are formed. The first and second compartments 141 and 142 are silencing chambers having an expansion chamber structure. The third compartment 143 is a compartment with a sound-absorbing structure, in which an exhaust gas flow pipe 143a made of a porous material such as punched metal is disposed, and a sound absorbing material 143b is filled to surround the exhaust gas flow pipe 143a. There is.

The exhaust passage 137 will be explained. The exhaust passage 137 of this example allows exhaust gas to flow through the first to third compartments 141 to 143 for noise reduction in sequence, as indicated by arrows in FIG. 4(a). Exhaust passage inlets 137a, 137b, and 137c are opened in a case lower surface portion 131a of silencer case 131 at positions corresponding to intermediate stage exhaust ports 114, 115 and final stage exhaust port 116, respectively. The upstream end of the exhaust passage 137 communicates with these exhaust passage entrances 137a to 137c. An exhaust passage outlet 137d is opened in the case upper surface portion 131b of the silencer case 131. The downstream end of the exhaust passage 137 communicates with this exhaust passage outlet 137d. The exhaust gas from the multi-stage dry vacuum pump 110 flows through the exhaust passage 137 inside the silencer 130 and sequentially through the first to third compartments 141 to 143 for noise reduction, and then exits from the exhaust pipe 135. It is discharged to the outside.

Here, the silencer case 131 of this example is made of aluminum, aluminum alloy, or other metal material that has higher thermal conductivity than the pump casing 111 of the multistage dry vacuum pump 110.

Furthermore, a drain mechanism is incorporated in the bottom wall portion of the case body 132 that defines the final third compartment 143 to discharge condensed water and the like generated inside the silencer to the outside. A drain plug 144 is attached to a drain outlet opening on the outer peripheral surface of the case body 132.

Furthermore, a gas ballast mechanism 170 that introduces ballast gas to the multi-stage dry vacuum pump 110 side is incorporated in the case body 132. A ballast gas inlet 171 for introducing ballast gas from the outside is opened in an upper surface portion 132b of the case body 132 that is not covered by the case lid 133. The ballast gas inlet 171 communicates with a ballast gas communication passage 172 formed inside the case body 132. A filter 172a, a ball type check valve 172b, and the like are arranged in the ballast gas communication passage 172. The other end of the ballast gas communication passage 172 opens to the case outer peripheral surface 132a of the case body 132, and a communication pipe 173 (see FIG. 3(a)) is connected thereto. The communication pipe 173 communicates with the ballast gas inlet 119 of the multistage dry vacuum pump 110 via an on-off valve 174 (see FIG. 3(a)).

In the vacuum evacuation device 100 (dry vacuum pump device) configured in this way, a silencer 130 having an intake pipe 134 and an exhaust pipe 135 is attached to the upper part of the horizontally placed multi-stage dry vacuum pump 110 and integrated. There is. Since the silencer 130 including the intake pipe 134 and the exhaust pipe 135 is arranged using the space in the multi-stage dry vacuum pump 110 where the intake pipe and exhaust pipe are installed, the installation space required for installing the silencer 130 is reduced. This is advantageous in making the vacuum evacuation device 100 smaller and more compact. Moreover, since the drain mechanism and the gas ballast mechanism 170 are built into the silencer 130, this is also advantageous in making the vacuum pumping apparatus 100 smaller and more compact.

Furthermore, the silencer case 131 attached to the pump casing 111 of the multistage dry vacuum pump 110 is made of a material with high thermal conductivity. Heat generated by the multistage dry vacuum pump 110 is efficiently transferred to the silencer case 131. Since the silencer 130 is efficiently heated by the heat generated by the multi-stage dry vacuum pump 110, it is possible to prevent condensed water from accumulating inside the silencer 130 when flowing condensable gas without heating it using a heater.

Note that the evacuation device 100 of this example is equipped with a multistage dry vacuum pump 110. The vacuum evacuation device 100 having this configuration is generally used by connecting a mechanical booster pump to the front side of the multistage dry vacuum pump 110.

In this case, the silencer 130 disposed above the multistage dry vacuum pump 110 is disposed between the mechanical booster pump and the multistage dry vacuum pump 110. Therefore, as in the case of the evacuation device 1 of the first embodiment described above, a joint pipe can be integrally formed in the silencer 130 as the intake passage 136. Further, the case lid 133 of the silencer case 131 can have the function of the connecting flange 70 in the first embodiment. In this way, the same effects as in the first embodiment can be obtained.

Claims (8)

mechanical booster pump,
Positive displacement dry vacuum pump,
a joint pipe connecting a front-stage pump exhaust port, which is a pump exhaust port of the mechanical booster pump, and a rear-stage pump intake port, which is a pump intake port of the dry vacuum pump;
a silencer that reduces noise when exhaust gas is discharged from a rear-stage pump exhaust port that is a pump exhaust port of the dry vacuum pump;
It is equipped with
The mechanical booster pump and the dry vacuum pump are arranged such that the front-stage pump exhaust port of the mechanical booster pump and the rear-stage pump intake port of the dry vacuum pump face each other at a predetermined interval,
The silencer is arranged to surround the outer periphery of the joint pipe between the front-stage pump exhaust port of the mechanical booster pump and the rear-stage pump intake port of the dry vacuum pump. Vacuum exhaust equipment. The vacuum evacuation device according to claim 1,
The silencer is
a silencer case in which the joint pipe is integrally formed;
a plurality of silencing compartments arranged to surround the joint pipe inside the silencer case;
an exhaust passage that communicates with the rear-stage pump exhaust port and allows the exhaust to flow sequentially through each of the silencing compartments;
Vacuum exhaust equipment equipped with. The vacuum evacuation device according to claim 2,
The dry vacuum pump is placed horizontally,
The mechanical booster pump is placed horizontally above the dry vacuum pump,
The rear-stage pump intake port and the rear-stage pump exhaust port of the dry vacuum pump are opened at an upper portion of the dry vacuum pump facing the mechanical booster pump,
The first-stage pump exhaust port of the mechanical booster pump is opened at a lower part of the mechanical booster pump that faces the second-stage pump intake port of the dry vacuum pump,
The upper end opening of the joint pipe of the silencer case is connected to the front pump exhaust port of the mechanical booster pump, and the lower end opening of the joint pipe is connected to the rear pump intake port of the dry vacuum pump, A vacuum exhaust device, wherein an exhaust passage inlet of the exhaust passage is connected to the downstream pump exhaust port of the dry vacuum pump. The vacuum evacuation device according to claim 3,
The silencer case is a vacuum evacuation device that is attached to the pump casing of the dry vacuum pump or the mechanical booster pump via a vibration absorbing material. The vacuum evacuation device according to claim 2,
In the evacuation device, the silencer case is formed of a material having higher thermal conductivity than the pump casings of the dry vacuum pump and the mechanical booster pump. The vacuum evacuation device according to claim 2,
The silencer is a vacuum exhaust device including, as the sound-muffling compartment, a compartment having an expansion chamber structure arranged on the upstream side in the flow direction of the exhaust gas, and a compartment having a sound absorbing structure arranged on the downstream side. The vacuum evacuation device according to claim 2 ,
The silencer is a vacuum evacuation device including a drain mechanism that discharges condensed water generated in the noise-muffling compartment to the outside. The vacuum evacuation device according to claim 1,
The silencer is a vacuum exhaust device including a gas ballast mechanism including a ballast gas passage and a check valve for guiding ballast gas from the outside to the ballast gas inlet of the dry vacuum pump.