Screw vacuum pump

Abstract

The utility model relates to the technical field of vacuum pumps, in particular to a screw vacuum pump. Comprising a screw rod which is rotatably arranged in a pump body; the screw rod comprises a rod body; the shaft hole is formed in the central spiral groove of the rod body and is formed in the periphery of the shaft hole; a core shaft is inserted into the shaft hole and comprises a shaft body embedded in the shaft hole; the center hole is formed in the center of the shaft body. An annular groove is formed in the end of the shaft body, and the center hole is communicated with the annular groove through the flow groove. The pump body is provided with a rotary joint; the rotary joint is communicated with the central hole; and spoilers are arranged in the spiral grooves and are communicated with the spiral grooves through the annular flow channels. The spoiler is provided with a cantilever piece, one end of the cantilever piece is fixedly connected to the spoiler, and the other end of the cantilever piece is in a free state. And the spoilers are spirally wound on the periphery of the core shaft. The heat dissipation performance of the screw can be improved, and long-term stable operation of equipment is guaranteed.

Description

TECHNICAL FIELD

[0001] The utility model relates to vacuum pump technical field, concretely is screw rod vacuum pump. BACKGROUND

[0002] Screw rod vacuum pump is a kind of vacuum equipment based on dry volume principle, and its core working component is a pair of precision meshing double screw rotors.In the synchronous reverse rotation process, rotor and pump cavity form the closed space of continuous change, and sequentially complete the work cycle of gas suction, compression and discharge.As the representative of oil-free vacuum equipment, its working medium does not need to participate in lubricating oil, so it has significant advantages in the industrial field with strict requirements on cleanliness and corrosion resistance.

[0003] At present, the heat management of screw rod vacuum pump generally adopts pump shell indirect cooling scheme, that is, spiral or annular cooling water cavity is arranged on the pump body and bearing seat shell, and pump shell surface temperature control is realized by circulating cooling medium.However, under long-time high-load working condition, the heat generated by gas compression of rotor is difficult to conduct and radiate quickly through pump shell, which leads to the formation of significant temperature gradient between rotor and pump body, and easily causes rotor thermal deformation and occlusion jamming fault risk.In order to further optimize the heat dissipation path, the prior art proposes to additionally arrange axial through cooling channels in the rotor, and realizes direct heat exchange by feeding cooling medium into the shaft core of the rotor.The scheme improves the heat dissipation efficiency of the rotor to a certain extent, but due to the limited specific surface area of single axial channel and the disordered medium flow path, there are still technical bottlenecks such as poor cooling uniformity and uneven heat resistance distribution, especially when dealing with large-size rotor or high compression ratio working condition, the heat dissipation capacity is difficult to meet the long-term stable operation demand of the equipment. UTILITY MODEL CONTENTS

[0004] In order to solve the technical problems in the background art, the utility model provides a screw rod vacuum pump, which can improve the heat dissipation performance of the screw rod and ensure the long-term stable operation of the equipment.

[0005] The technical scheme adopted by the utility model to solve its technical problems is:

[0006] The screw rod vacuum pump comprises:

[0007] The screw rod is rotatably arranged in the pump body.

[0008] The screw rod comprises:

[0009] The rod body;

[0010] The shaft hole is arranged at the center of the rod body.

[0011] The spiral groove is arranged on the outer periphery of the shaft hole.

[0012] The shaft hole is inserted with the mandrel, and the mandrel comprises:

[0013] The shaft body is embedded in the shaft hole.

[0014] The central hole is arranged in the center of the shaft body.

[0015] Further, the end of the shaft body is provided with an annular groove, and the central hole is communicated with the annular groove through the flow groove.

[0016] Further, the pump body is provided with a rotary joint, and the rotary joint comprises:

[0017] The first flow channel is communicated with the central hole;

[0018] The second flow channel is communicated with the spiral groove through the annular flow channel.

[0019] Further, the spiral groove is provided with a spoiler.

[0020] Further, the spoiler is provided with a cantilever piece, one end of the cantilever piece is fixedly connected to the spoiler, and the other end of the cantilever piece is in a free state.

[0021] Further, the spoiler is spirally arranged on the outer periphery of the mandrel.

[0022] Further, the screw rod is driven by a motor.

[0023] The beneficial effects of the utility model are as follows:

[0024] (1) The heat dissipation design can significantly improve the heat conduction efficiency of the screw rod, and ensure the operation stability of the equipment under continuous high load working conditions.

[0025] (2) The spiral flow channel system formed by the mandrel and the spiral groove prolongs the ordered flow path of the cooling liquid, increases the heat exchange time of the cooling liquid and the contact surface, and can realize more effective and more uniform heat dissipation.

[0026] (3) The axial embedded assembly process is adopted between the mandrel and the screw rod, which can ensure the feasibility of the flow channel structure process, improve the overall structural rigidity through the cooperation of the mandrel and the shaft hole, and effectively balance the heat dissipation performance and mechanical strength.

[0027] (4) Based on the dynamic spoiler mechanism of centrifugal force self-adaptation, the opening angle of the cantilever piece is positively correlated with the rotating speed of the screw rod. When the rotating speed increases, the opening angle of the cantilever piece increases, the heat exchange efficiency is improved by enhancing the turbulence degree of the cooling liquid, and the self-adaptive enhanced heat dissipation effect is formed. BRIEF DESCRIPTION OF DRAWINGS

[0028] The utility model will be further described below in combination with the drawings and examples.

[0029] Figure 1 It is a sectional view of the utility model;

[0030] Figure 2This is a schematic diagram of the structure of this utility model;

[0031] Figure 3 This is a schematic diagram of the screw structure;

[0032] Figure 4 This is a schematic diagram of the mandrel structure;

[0033] Figure 5 This is a schematic diagram of the rotary joint.

[0034] Figure 6 This is a schematic diagram of the spoiler structure;

[0035] Figure 7 This is a diagram showing the working state of the spoiler.

[0036] In the picture:

[0037] 1. Pump body, 2. Motor, 3. Screw, 4. Spindle, 5. Rotary joint, 6. Baffle plate;

[0038] 301. Rod body; 302. Shaft hole; 303. Spiral groove;

[0039] 401. Shaft body, 402. Center hole, 403. Annular groove, 404. Flow groove;

[0040] 501. First flow channel; 502. Annular flow channel; 503. Second flow channel;

[0041] 601. Cantilever plate. Detailed Implementation

[0042] The present invention will be further described in detail below with reference to the accompanying drawings.

[0043] like Figure 1 , 2 As shown, the specific structure of the screw vacuum pump includes two meshing screws 3, which are rotatably mounted in the pump body 1. The two screws 3 can rotate synchronously in opposite directions, and the screws 3 are driven by a motor 2. During synchronous reverse rotation, a continuously changing sealed space can be formed between the screws 3 and the pump chamber of the pump body 1, thereby completing the working cycle of gas intake, compression, and discharge in sequence.

[0044] like Figure 3 As shown, the screw 3 includes a rod body 301, which is rotatably connected to the pump body 1. A blind hole 302 is machined at the central axis of the rod body 301. A helical groove 303 is formed on the outer periphery of the shaft hole 302. The axial extension of the shaft hole 302 completely covers the effective working area of ​​the screw 3's meshing portion, and by limiting the depth of the shaft hole 302, sufficient heat dissipation is ensured during meshing transmission.

[0045] likeFigure 4 As shown in the figure, the shaft hole 302 is inserted with a mandrel 4. The specific structure of the mandrel 4 includes a shaft body 401, which is embedded in the shaft hole 302, and the outer side wall of the shaft body 401 is in contact with the inner side wall of the shaft hole 302. The outer side wall of the shaft body 401 and the spiral groove 303 can form a spiral flow channel for the circulation of the cooling liquid. The spiral flow channel system formed by the mandrel 4 and the spiral groove 303 can prolong the orderly flow path of the cooling liquid, increase the heat exchange time of the cooling liquid and the contact surface, and achieve more effective and uniform heat dissipation.

[0046] The center hole 402 is provided in the center of the shaft body 401. The end of the shaft body 401 is provided with an annular groove 403, and the center hole 402 is communicated with the annular groove 403 through a flow groove 404. In the specific implementation, the cooling liquid flows through the spiral groove 303, the annular groove 403, the flow groove 404 and the center hole 402 in sequence. The axial embedding assembly process is adopted between the mandrel 4 and the screw rod 3, which can ensure the feasibility of the flow channel structure process, and at the same time, the overall structure stiffness is improved through the cooperation of the mandrel 4 and the shaft hole 302, effectively balancing the heat dissipation performance and mechanical strength.

[0047] As shown in the figure, Figure 5 The pump body 1 is provided with a rotary joint 5. The specific structure of the rotary joint 5 includes a first flow channel 501, which is communicated with the center hole 402. The second flow channel 503 is communicated with the spiral groove 303 through the annular flow channel 502. The rotary joint 5 is rotatably connected with the screw rod 3 and the mandrel 4 through the sealing ring. The cooling liquid enters the spiral groove 303 from the second flow channel 503, and the cooling liquid in the center hole 402 flows out from the first flow channel 501.

[0048] As shown in the figure, Figure 6 , 7 The spiral groove 303 is provided with a turbulence plate 6. The turbulence plate 6 is spirally arranged on the outer periphery of the mandrel 4. The turbulence plate 6 is arranged in the spiral flow channel formed by the outer side wall of the shaft body 401 and the spiral groove 303. The turbulence plate 6 can enhance the turbulence degree of the cooling liquid in the spiral flow channel, thereby improving the heat exchange efficiency.

[0049] The turbulence plate 6 is also provided with a plurality of cantilever plates 601, one end of which is fixedly connected to the turbulence plate 6, and the other end is in a free state. In the specific implementation, the turbulence plate 6 is formed by bending the sheet metal, and the cantilever plate 601 is formed by laser cutting on the sheet metal. The centrifugal force generated by the rotation of the screw rod 3 can cause the cantilever plate 601 to elastically deform outward.

[0050] The cantilever piece 601 can form a centrifugal force self-adaptive dynamic flow disturbance mechanism, and the opening angle of the cantilever piece 601 is in a positive correlation with the rotating speed of the screw rod 3. When the rotating speed of the screw rod 3 increases, the heat generated by the screw rod 3 is greater. The centrifugal force of the rotation of the screw rod 3 causes the opening angle of the cantilever piece 601 to increase. The cantilever piece 601 actively disturbs the flow field structure, and when the opening angle of the cantilever piece 601 increases, the cooling liquid in the spiral flow channel has a significantly enhanced turbulent effect due to the intensified flow velocity gradient. The greater the opening angle of the cantilever piece 601, the more significant the flow disturbance effect of the cantilever piece 601 on the cooling liquid in the spiral flow channel, and the turbulent degree of the cooling liquid in the spiral flow channel will significantly increase. By enhancing the turbulent degree of the cooling liquid, the heat exchange efficiency is improved, and a rotating speed self-adaptive heat dissipation effect is formed.

[0051] Based on the above ideal embodiments of the present application, through the above description, relevant personnel can make various changes and modifications without deviating from the technical concept of the present application. The technical scope of the present application is not limited to the content in the specification, and must be determined according to the scope of the claims.

Claims

1. Screw vacuum pump, characterized in that The screw rod (3) is rotatably arranged in the pump body (1). The screw rod (3) comprises: a rod body (301); an axial hole (302) arranged at the center of the rod body (301); a helical groove (303) arranged on the outer periphery of the axial hole (302). The axial hole (302) is inserted with a mandrel (4), and the mandrel (4) comprises: an axial body (401) embedded in the axial hole (302); a central hole (402) arranged at the center of the axial body (401).

2. The screw rod vacuum pump according to claim 1, wherein an annular groove (403) is arranged at the end of the axial body (401), and the central hole (402) is communicated with the annular groove (403) through a flow groove (404).

3. The screw rod vacuum pump according to claim 1, wherein the pump body (1) is provided with a rotary joint (5), and the rotary joint (5) comprises: a first flow channel (501) communicated with the central hole (402); a second flow channel (503) communicated with the helical groove (303) through an annular flow channel (502).

4. The screw rod vacuum pump according to claim 1, wherein a spoiler (6) is arranged in the helical groove (303).

5. The screw rod vacuum pump according to claim 4, wherein the spoiler (6) is provided with a cantilever piece (601), one end of the cantilever piece (601) is fixedly connected to the spoiler (6), and the other end of the cantilever piece (601) is in a free state.

6. The screw rod vacuum pump according to claim 5, wherein the spoiler (6) is helically arranged on the outer periphery of the mandrel (4).

7. The screw rod vacuum pump according to claim 1, wherein the screw rod (3) is driven by a motor (2). ​

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