A cooling system for a dry vacuum pump unit

Abstract

The present invention relates to the technical field of vacuum pumps, and particularly relates to a cooling system for a dry vacuum pump unit, including: the water inlet end of the first pipeline is communicated with the first chamber, and the first chamber is a coolant channel arranged near the first part of the dry vacuum pump unit; one end of the second pipeline is connected to the water outlet end of the first pipeline through a constant flow valve, and the other end is communicated with the second chamber, and the second chamber is a coolant channel arranged near the second part of the dry vacuum pump unit; the first part is the bearing where the gear is installed, and correspondingly, the second part is the motor; or, the first part is at the rear-stage main pump group, and correspondingly, the second part is the front-stage pump; by adding a constant flow valve in this application, the coolant flow is restricted, the cooling speed of the motor end or the front-stage pump is reduced, so that the motor end or the front-stage pump maintains a relatively high temperature, avoiding the formation of a temperature difference; and the temperature distribution of the dry vacuum pump unit is made balanced.

Description

Technical Field

[0001] The present invention relates to the technical field of vacuum pumps, and particularly to a cooling system for a dry vacuum pump unit. Background Art

[0002] Dry vacuum pump units, especially Roots-screw dry vacuum pump units composed of a Roots pump and an oil-free screw vacuum pump, are widely used in the semiconductor industry. For example, different gases are generated in different processes of semiconductor product processing, and different gases have certain critical condensation temperatures. In order to prevent gas condensation, the temperature of the working space of the Roots-screw dry vacuum pump unit needs to be kept consistent. Therefore, during the operation of the Roots-screw dry vacuum pump unit, a cooling system is required for cooling, for cooling the motor and the vacuum pump cavity, etc., to prevent some components from stopping due to excessive temperature. However, during the operation of the Roots-screw dry vacuum pump unit, there is a phenomenon that the overall temperature of the Roots pump is relatively low, while the temperature of the oil-free screw vacuum pump is relatively high, and there is also a phenomenon that the temperature at the motor end is lower than that at the gear end; that is, when the Roots-screw dry vacuum pump unit is working, there is a problem of uneven temperature distribution. Summary of the Invention

[0003] Therefore, the technical problem to be solved by the present invention is to overcome the defect of uneven temperature distribution when the Roots-screw dry vacuum pump unit is working.

[0004] To overcome the above defects, the present invention provides a cooling system for a dry vacuum pump unit, including:

[0005] A first pipeline, the water inlet end of which is communicated with a first chamber, and the first chamber is a coolant passage arranged near the first part of the dry vacuum pump unit;

[0006] A second pipeline, one end of which is connected to the water outlet end of the first pipeline through a constant flow valve, and the other end is communicated with a second chamber, and the second chamber is a coolant passage arranged near the second part of the dry vacuum pump unit; the first part is the bearing where the gear is installed, correspondingly, the second part is the motor; or, the first part is the rear-stage main pump group, correspondingly, the second part is the front-stage pump; the dry vacuum pump unit is a front-stage pump and a rear-stage main pump group connected in series in sequence;

[0007] A third pipeline, one end of which is communicated with the second chamber, and the third pipeline is adapted to output the coolant in the second chamber.

[0008] Optionally, it further includes:

[0009] A fourth pipeline, which is connected to the other end of the third pipeline, and the fourth pipeline is adapted to discharge the coolant in the third pipeline;

[0010] The fifth pipeline is connected to the fourth pipeline at one end and to the first pipeline at the other end.

[0011] Optionally, it further includes:

[0012] A first three-way joint, with the first end connected to the water outlet end of the first pipeline, the second end of the first three-way joint connected to the constant flow valve, and the third end of the first three-way joint connected to the fifth pipeline;

[0013] A second three-way joint, with the first end connected to the third pipeline, the second end of the second three-way joint connected to the fourth pipeline, and the third end of the second three-way joint connected to the fifth pipeline.

[0014] Optionally, the constant flow valve includes:

[0015] A valve body provided with a through hole, and the through hole is suitable for the coolant to flow through;

[0016] A valve core slidably connected in the through hole; on the downstream side of the valve core along the coolant flow direction, there is a throttling portion, and the shape of the throttling portion gradually decreases from the end to the bottom; there is also an intermediate channel in the valve core, and the intermediate channel communicates the upstream and downstream of the valve core along the coolant flow direction;

[0017] A throttling member snap-fitted in the through hole and located downstream of the valve core along the coolant flow direction, and a throttling hole is provided on the throttling member; the throttling portion is suitable for the valve core to slide towards the direction close to the throttling member as the pressure of the coolant on the valve core increases, and the greater the depth of the throttling portion inserted into the throttling hole;

[0018] An elastic member located in the through hole, with one end of the elastic member abutting against the valve core and the other end abutting against the throttling member.

[0019] Optionally, the constant flow valve further includes:

[0020] A plug plate fixedly arranged in the through hole and located upstream of the valve core along the coolant flow direction, a through hole is provided on the plug plate, and a filter screen is provided on the through hole.

[0021] Optionally, an annular groove is provided on the inner wall of the through hole of the valve body, and the edge of the plug plate is embedded in the annular groove.

[0022] Optionally, the valve core further has:

[0023] A connecting portion connected to the throttling portion, and the cross-sectional dimension of the connecting portion is larger than that of the throttling portion;

[0024] A sliding portion connected to the connecting portion, and the sliding portion is in sliding fit with the through hole.

[0025] Optionally, the intermediate channel is a first hole and a second hole that are communicatively connected. The first hole is disposed at an end of the valve core away from the throttling member, and the first hole communicates with the upstream of the valve core along the coolant flow direction; the second hole is disposed perpendicular to the first hole, and the second hole is disposed on the connecting portion, and the second hole communicates with the downstream of the valve core along the coolant flow direction.

[0026] Optionally, the elastic member is a spring, and the spring is sleeved on the connecting portion.

[0027] Optionally, the throttling member is provided with an annular flange, and an annular shoulder is provided in the through hole of the valve body. The annular flange is snap-connected by abutting against the annular shoulder.

[0028] The above technical solution of the present invention has the following advantages compared with the prior art:

[0029] 1. The cooling system for a dry vacuum pump unit provided by the present invention includes: a first pipeline, the water inlet end of which communicates with a first chamber, and the first chamber is a coolant channel disposed near the first part of the dry vacuum pump unit; a second pipeline, one end of which is connected to the water outlet end of the first pipeline through a constant flow valve, and the other end communicates with a second chamber, and the second chamber is a coolant channel disposed near the second part of the dry vacuum pump unit; the first part is the bearing where the gear is installed, and correspondingly, the second part is the motor; or, the first part is at the rear-stage main pump group, and correspondingly, the second part is the front-stage pump; the dry vacuum pump unit is a front-stage pump and a rear-stage main pump group connected in series in sequence; a third pipeline, one end of which communicates with the second chamber, and the third pipeline is adapted to output the coolant in the second chamber; by adopting the above technical solution, the present application adds a constant flow valve to the cooling system for a dry vacuum pump unit, restricts the flow rate of the coolant, reduces the cooling speed of the motor end or the front-stage pump, enables the motor end or the front-stage pump to maintain a relatively high temperature, avoids forming a temperature difference between the motor end and the gear end, or between the front-stage pump and the rear-stage main pump group; makes the temperature distribution of the dry vacuum pump unit balanced, prevents gas condensation during semiconductor product processing, and effectively improves the gas exhaust efficiency, especially the ability to exhaust waste gas.

[0030] 2. The cooling system for a dry vacuum pump unit provided by the present invention further includes: a fourth pipeline, connected to the other end of the third pipeline, and the fourth pipeline is adapted to discharge the coolant in the third pipeline; a fifth pipeline, one end of which is connected to the fourth pipeline, and the other end is connected to the first pipeline; by adopting the above technical solution, the present application discharges the coolant in the third pipeline and the fifth pipeline through the fourth pipeline, forming a continuously flowing coolant, and improving the cooling efficiency of the coolant.

[0031] 3. The cooling system for the dry vacuum pump unit provided by the present invention further includes: a first three-way joint, the first end of which is connected to the water outlet end of the first pipeline, the second end of the first three-way joint is connected to the constant flow valve, and the third end of the first three-way joint is connected to the fifth pipeline; a second three-way joint, the first end of which is connected to the third pipeline, the second end of the second three-way joint is connected to the fourth pipeline, and the third end of the second three-way joint is connected to the fifth pipeline. By adopting the above technical solution of the present application, the first pipeline, the constant flow valve and the fifth pipeline can be conveniently connected through the first three-way joint; the third pipeline, the fourth pipeline and the fifth pipeline can be conveniently connected through the second three-way joint; at the same time, it is also convenient for disassembly and maintenance.

[0032] 4. The constant flow valve of the present invention includes: a valve body provided with a through hole suitable for the circulation of the coolant; a valve core slidably connected in the through hole; a throttling portion is provided on the downstream side of the valve core along the coolant flow direction, and the shape of the throttling portion gradually decreases from the end to the bottom; an intermediate channel is further provided in the valve core, and the intermediate channel communicates the upstream and downstream of the valve core along the coolant flow direction; a throttling member is snap-fitted in the through hole and is located downstream of the valve core along the coolant flow direction, and a throttling hole is provided in the throttling member; the throttling portion is adapted to slide the valve core in the direction close to the throttling member as the pressure of the coolant on the valve core increases, and the greater the depth of the throttling portion inserted into the throttling hole; an elastic member is located in the through hole, one end of the elastic member abuts against the valve core, and the other end of the elastic member abuts against the throttling member. By adopting the above technical solution of the present application, when the pressure of the coolant increases, the pressure of the coolant on the valve core increases, and the valve core slides in the direction close to the throttling member. After the valve core compresses the elastic member to a certain extent, the depth of the throttling portion inserted into the throttling hole increases, the effective flow area decreases, and the flow rate of the coolant through the throttling hole increases, so as to keep the flow rate of the coolant passing through the constant flow valve constant, thereby achieving the function of current limiting, and the flow rate of the coolant output under different pressures can be matched to be the same. Moreover, the structure of the constant flow valve is simple, easy to produce and process, and has high durability.

[0033] 5. The constant flow valve of the present invention further includes: a plug plate fixedly provided in the through hole and located upstream of the valve core along the coolant flow direction, a through hole is provided in the plug plate, and a filter screen is provided in the through hole. By adopting the above technical solution of the present application, the plug plate provided with the filter screen can filter out some impurities in the coolant, prevent blockage, and keep the coolant flowing smoothly.

[0034] 6. A ring groove is provided on the inner wall of the through hole of the valve body of the present invention, and the edge of the plug plate is embedded in the ring groove. By adopting the above technical solution of the present application, it is ensured that the plug plate is firmly arranged.

[0035] 7. The spool of the present invention further comprises: a connecting portion connected to the throttling portion, the cross-sectional dimension of the connecting portion being larger than that of the throttling portion; a sliding portion connected to the connecting portion, the sliding portion being in sliding fit with the through hole. By adopting the above technical solution, the strength of the spool is ensured to be sufficient, firm and reliable.

[0036] 8. The intermediate passage of the present invention is a first hole and a second hole which are connected in communication. The first hole is arranged at one end of the spool away from the throttling member, and the first hole is in communication with the upstream along the coolant flow direction on the spool; the second hole is arranged perpendicular to the first hole, and the second hole is arranged on the connecting portion, and the second hole is in communication with the downstream along the coolant flow direction on the spool. By adopting the above technical solution, the intermediate passage is arranged on the connecting portion and the sliding portion with relatively large dimensions, ensuring sufficient strength, firmness and reliability of the spool while ensuring the smooth flow of the coolant.

[0037] 9. The elastic member of the present invention is a spring, and the spring is sleeved on the connecting portion. By adopting the above technical solution, through the connecting portion, a certain force application guidance is carried out on the spring to prevent the force application from being skewed.

[0038] 10. The throttling member is provided with an annular flange, and an annular shoulder is arranged in the through hole of the valve body. The annular flange is in snap connection by abutting against the annular shoulder. By adopting the above technical solution, the installation of the throttling member is ensured to be firm and reliable. Description of the Drawings

[0039] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the drawings required for the description of the specific embodiments or the prior art. Obviously, the following drawings are some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0040] Figure 1 It is a schematic connection structure diagram of a cooling system for a dry vacuum pump unit provided in the embodiment of the present invention;

[0041] Figure 2 It is a schematic cross-sectional structure diagram of a constant flow valve provided in the embodiment of the present invention.

[0042] Description of the Reference Numerals:

[0043] 1. First pipeline; 2. First three-way joint; 3. Constant flow valve; 4. Second pipeline; 5. Third pipeline; 6. Second three-way joint; 7. Fourth pipeline; 8. Fifth pipeline; 9. Valve body; 10. Plug plate; 11. Spool; 12. Elastic member; 13. Throttling member. Detailed Implementation Modes

[0044] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0045] In the description of the present invention, it should be noted that the orientation or positional relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation of the present invention. In addition, the terms "first", "second", "third" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance.

[0046] In the description of the present invention, it should be noted that unless otherwise clearly specified and limited, the terms "installed", "connected", "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

[0047] In addition, the technical features involved in different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0048] Such as Figures 1 to 2A specific embodiment of the cooling system for a dry vacuum pump unit is shown, including: a first pipeline 1, a first three-way joint 2, a constant flow valve 3, and a second pipeline 4 connected in sequence, a third pipeline 5, a second three-way joint 6, and a fourth pipeline 7 connected in sequence, and a fifth pipeline 8 connected to the second three-way joint 6. The dry vacuum pump unit is a front-stage pump and a rear-stage main pump group connected in series in sequence. When the dry vacuum pump unit is a Roots-screw dry vacuum pump unit, the front-stage pump is a Roots pump, and the rear-stage main pump group is an oil-free screw vacuum pump. When the dry vacuum pump unit is a Roots-claw dry vacuum pump unit, the front-stage pump is a Roots pump, and the rear-stage main pump group is a claw pump. When the dry vacuum pump unit is a Roots-multi-stage Roots dry vacuum pump unit, the front-stage pump is a front-stage Roots pump, and the rear-stage main pump group is a multi-stage Roots pump. For the dry vacuum pump unit, the motor drives the gear to rotate, and two relatively rotating gears respectively drive a pair of rotors of the front-stage pump to rotate, and then respectively drive the corresponding rotors of the rear-stage main pump group to rotate through the pair of rotors.

[0049] As Figure 1 shown, the water inlet end of the first pipeline 1 is communicated with the first chamber, and the first chamber is a coolant channel arranged near the first part of the dry vacuum pump unit; one end of the second pipeline 4 is connected to the water outlet end of the first pipeline 1 through the constant flow valve 3, and the other end of the second pipeline 4 is communicated with the second chamber, and the second chamber is a coolant channel arranged near the second part of the dry vacuum pump unit; the first part is the bearing where the gear is installed, and correspondingly, the second part is the motor; or, the first part is at the rear-stage main pump group, and correspondingly, the second part is the front-stage pump. One end of the third pipeline 5 is communicated with the second chamber, the fourth pipeline 7 is connected to the other end of the third pipeline 5, and the fourth pipeline 7 is adapted to discharge the coolant in the third pipeline 5; one end of the fifth pipeline 8 is connected to the fourth pipeline 7, and the other end of the fifth pipeline 8 is connected to the first pipeline 1. The first end of the first three-way joint 2 is connected to the water outlet end of the first pipeline 1, the second end of the first three-way joint 2 is connected to the constant flow valve 3, and the third end of the first three-way joint 2 is connected to the fifth pipeline 8; the first end of the second three-way joint 6 is connected to the third pipeline 5, the second end of the second three-way joint 6 is connected to the fourth pipeline 7, and the third end of the second three-way joint 6 is connected to the fifth pipeline 8. Specifically, the coolant is cooling water.

[0050] As Figure 2 shown, the constant flow valve 3 includes: a valve body 9, a valve core 11 slidably connected in the valve body 9, a throttling member 13 snap-fitted in the valve body 9, an elastic member 12 and a plug 10 arranged in the valve body 9. Among them, Figure 2 the arrow in

[0051] The valve body 9 is provided with a through hole adapted to allow the flow of coolant; the valve core 11 is slidably connected in the through hole; on the downstream side of the valve core 11 along the coolant flow direction, there are provided a throttling portion, a connecting portion connected to the throttling portion, and a sliding portion connected to the connecting portion. The shape of the throttling portion gradually decreases from the end to the bottom. Specifically, the shape of the throttling portion is conical; the cross-sectional dimension of the connecting portion is larger than that of the throttling portion; the sliding portion is in sliding fit with the through hole. An intermediate passage is further provided in the valve core 11, and the intermediate passage communicates the upstream and downstream of the valve core 11 along the coolant flow direction. The throttling member 13 is snap-fitted in the through hole and is located downstream of the valve core 11 along the coolant flow direction. A throttling hole is provided in the throttling member 13; the throttling portion is adapted to slide the valve core 11 in the direction close to the throttling member 13 as the pressure of the coolant on the valve core 11 increases, and the greater the depth of the throttling portion inserted into the throttling hole. The elastic member 12 is located in the through hole. One end of the elastic member 12 abuts against the valve core 11, and the other end of the elastic member 12 abuts against the throttling member 13. The plug plate 10 is fixedly provided in the through hole and is located upstream of the valve core 11 along the coolant flow direction. A through hole is provided in the plug plate 10, and a filter screen is provided in the through hole. Specifically, a ring groove is provided on the inner wall of the through hole of the valve body 9, and the edge of the plug plate 10 is embedded in the ring groove. The intermediate passage is a first hole and a second hole that are communicatively arranged. The first hole is provided at one end of the valve core 11 away from the throttling member 13 and communicates with the upstream of the valve core 11 along the coolant flow direction; the second hole is perpendicular to the first hole and is provided on the connecting portion, and the second hole communicates with the downstream of the valve core 11 along the coolant flow direction. The elastic member 12 is a spring, and the spring is sleeved on the connecting portion; the spring is a high-strength stainless steel spring. The throttling member 13 is provided with a ring flange, and a ring shoulder is provided in the through hole of the valve body 9. The ring flange forms a snap-fit by abutting against the ring shoulder.

[0052] The main working process of the cooling system for the dry vacuum pump unit described in this application is briefly described as follows: Cooling water flows from the first pipeline 1 and is split into two parallel paths through the first three-way joint 2. One path passes through the constant flow valve 3 and the second chamber for cooling the motor, and merges with the cooling water in the fifth pipeline 8 at the position of the second three-way joint 6. The flow rate of the cooling water is restricted by the constant flow valve 3, thereby reducing the cooling capacity of the motor end cavity or the fore pump, keeping the motor end cavity or the fore pump at a relatively high temperature, and avoiding the formation of a temperature difference; thus effectively improving the exhaust efficiency of the waste gas.

[0053] Obviously, the above embodiments are merely examples for clear illustration and are not limitations on the implementation manners. For those of ordinary skill in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation manners here. And the obvious changes or modifications derived therefrom still fall within the protection scope of the present invention.

Claims

1. A cooling system for a dry vacuum pump unit, characterized in that, Comprising: A first pipeline (1), the water inlet end of which is communicated with the first chamber, and the first chamber is a coolant passage provided near the first part of the dry vacuum pump unit; A second pipeline (4), one end of which is connected to the water outlet end of the first pipeline (1) through a constant flow valve (3), and the other end of which is communicated with the second chamber, and the second chamber is a coolant passage provided near the second part of the dry vacuum pump unit; the first part is the bearing where the gear is installed, correspondingly, the second part is the motor; or, the first part is at the rear-stage main pump group, correspondingly, the second part is the front-stage pump; the dry vacuum pump unit is a front-stage pump and a rear-stage main pump group connected in series in sequence; A third pipeline (5), one end of which is communicated with the second chamber, and the third pipeline (5) is adapted to output the coolant in the second chamber; Further comprising: A fourth pipeline (7), connected to the other end of the third pipeline (5), and the fourth pipeline (7) is adapted to discharge the coolant in the third pipeline (5); A fifth pipeline (8), one end of which is connected to the fourth pipeline (7), and the other end of which is connected to the first pipeline (1); Further comprising: A first three-way joint (2), the first end of which is connected to the water outlet end of the first pipeline (1), the second end of the first three-way joint (2) is connected to the constant flow valve (3), and the third end of the first three-way joint (2) is connected to the fifth pipeline (8); A second three-way joint (6), the first end of which is connected to the third pipeline (5), the second end of the second three-way joint (6) is connected to the fourth pipeline (7), and the third end of the second three-way joint (6) is connected to the fifth pipeline (8); The constant flow valve (3) comprises: A valve body (9), provided with a through hole, and the through hole is adapted to allow the coolant to flow through; A valve core (11), slidably connected in the through hole; on the downstream side of the valve core (11) along the coolant flow direction, a throttling part is provided, and the shape of the throttling part gradually decreases from the end to the bottom; an intermediate channel is further provided in the valve core (11), and the intermediate channel communicates the upstream and downstream of the valve core (11) along the coolant flow direction; A throttling member (13), snap-fitted in the through hole and located downstream of the valve core (11) along the coolant flow direction, and a throttling hole is provided in the throttling member (13); the throttling part is adapted to slide the valve core (11) towards the direction close to the throttling member (13) as the pressure of the coolant on the valve core (11) increases, and the greater the depth of the throttling part inserted into the throttling hole; An elastic member (12), located in the through hole, one end of the elastic member (12) abuts against the valve core (11), and the other end of the elastic member (12) abuts against the throttling member (13); The constant flow valve (3) further comprises: A plug plate (10), fixedly provided in the through hole and located upstream of the valve core (11) along the coolant flow direction, a through hole is provided in the plug plate (10), and a filter screen is provided on the through hole; The valve core (11) further has: A connecting part connected to the throttling part, and the cross-sectional dimension of the connecting part is larger than that of the throttling part; A sliding part connected to the connecting part, and the sliding part is slidably fitted with the through hole.

2. The cooling system for a dry vacuum pump unit according to claim 1, characterized in that, An annular groove is provided on the inner wall of the through hole of the valve body (9), and the edge of the blocking plate (10) is embedded in the annular groove.

3. The cooling system for a dry vacuum pump unit according to claim 1, characterized in that, The intermediate passage is a first hole and a second hole which are connected to each other. The first hole is arranged at an end of the valve core (11) away from the throttling member (13), and the first hole is connected to the upstream of the valve core (11) along the flow direction of the coolant. The second hole is arranged perpendicular to the first hole, and the second hole is arranged on the connecting portion, and the second hole is connected to the downstream of the valve core (11) along the flow direction of the coolant.

4. The cooling system for a dry vacuum pump unit according to claim 1, characterized in that, The elastic member (12) is a spring, and the spring is sleeved on the connecting portion.

5. The cooling system for a dry vacuum pump unit according to claim 1, characterized in that, The throttling member (13) is provided with an annular flange, and an annular shoulder is provided in the through hole of the valve body (9), and the annular flange is abutted against the annular shoulder to form a clamping arrangement.

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