Damping device and cryopump apparatus

Abstract

The application relates to a damping device and a cryogenic pump equipment, comprising a connecting unit, a damping unit, the connecting unit comprising a first connecting piece and a second connecting piece, the damping unit comprising an inner bellows and at least one outer bellows, the pipe diameter of the inner bellows being smaller than that of the outer bellows, the first connecting piece and the second connecting piece being arranged at two ends of the inner bellows respectively, the outer bellows being sleeved on the inner bellows, a medium for damping and a damping plate assembly being arranged between the inner bellows and the outer bellows, and the damping plate assembly being arranged along the axial direction of the inner bellows. The application does not need to change the existing structure of the cryogenic pump, and damping is realized by arranging an independent damping device on the cryogenic pump body, so that the close combination of the cold head and the pump body itself can be ensured, the performance of the cryogenic pump itself is not reduced, the problem of helium leakage does not occur, and the stability of production and the yield of products are improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of shock absorption technology of cryogenic pumps, in particular to a shock absorption device and a cryogenic pump equipment. BACKGROUND

[0002] A cryogenic pump is a vacuum pump that condenses gas on a low-temperature surface, also known as a condensing pump. The cryogenic pump is the ultimate vacuum pump with the lowest limit pressure and the largest pumping speed to obtain clean vacuum, and is widely used in the research and production of semiconductors and integrated circuits, as well as molecular beam research, vacuum coating equipment, vacuum surface analysis instruments, ion implanters and space simulation devices. The cryogenic pump is prone to vibration during operation and movement, and the vibration will cause the device state to be unstable, such as displacement of the thermocouple crucible, thereby affecting the normal operation of the device. In the prior art, the shock absorption method is to directly lock the cold head to the shock absorption mechanism, and then lock the shock absorption mechanism to the main body of the cryogenic pump.

[0003] The defect of the prior art is that in the case of rigid connection of various components, the degree of vibration reduction is actually very limited. In addition, the shock absorption structure is not tight enough when connected with the cold head, and is prone to looseness when subjected to vibration, thereby causing helium leakage and exacerbating vibration. Further, the existing shock absorption structure causes the distance between the cold head and the main body of the cryogenic pump to be far, thereby causing the heat conduction effect to be poor, which seriously reduces the performance of the cryogenic pump. SUMMARY

[0004] Therefore, the technical problem to be solved by the present application is to overcome the shortcomings of the prior art, and to provide a shock absorption device and a cryogenic pump equipment. The present application does not need to change the existing structure of the cryogenic pump, and realizes shock absorption by setting an independent shock absorption device on the main body of the cryogenic pump, thereby ensuring the close combination of the cold head and the main body of the pump, without reducing the performance of the cryogenic pump itself, and without the problem of helium leakage, improving the stability of production and the yield of products.

[0005] To solve the above technical problems, the present application provides a shock absorption device for absorbing shock of a cryogenic pump, comprising,

[0006] A connecting unit comprising a first connecting piece and a second connecting piece;

[0007] A shock absorption unit comprising an inner bellows and at least one outer bellows, the pipe diameter of the inner bellows being smaller than the pipe diameter of the outer bellows, the first connecting piece and the second connecting piece being respectively arranged at both ends of the inner bellows, the outer bellows being sleeved on the inner bellows, and a medium for shock absorption and a shock absorption plate assembly being arranged between the inner bellows and the outer bellows, the shock absorption plate assembly being arranged along the axial direction of the inner bellows.

[0008] Preferably, the shock-absorbing plate assembly comprises a plurality of first shock-absorbing plates and a plurality of second shock-absorbing plates arranged along the inner bellows in an axial direction, the plurality of first shock-absorbing plates and the plurality of second shock-absorbing plates being arranged alternately in sequence, and the first shock-absorbing plates and the second shock-absorbing plates are perpendicular to the direction of the axis of the inner bellows.

[0009] Preferably, the first shock-absorbing plates are provided with a plurality of first through holes, and the second shock-absorbing plates are provided with a plurality of second through holes, the projection area of the first through holes along the axial direction of the bellows is different from the projection area of the second through holes along the axial direction of the inner bellows.

[0010] Preferably, the shock-absorbing unit further comprises at least two movable connecting rods, the two movable connecting rods are arranged at two ends of the shock-absorbing plate assembly respectively and between the shock-absorbing plate assembly and the outer bellows, and the movable connecting rods are arranged along the direction of the axis of the inner bellows.

[0011] Preferably, the movable connecting rod comprises a shell, an elastic member and a telescopic rod arranged in the shell, the telescopic rod is connected with the elastic member, the shell is connected with the outer bellows, the telescopic rod is connected with the shock-absorbing plate assembly, and the telescopic rod can reciprocate along the length direction thereof.

[0012] Preferably, the movable connecting rod comprises a gas cylinder, the gas cylinder is mounted on the outer bellows, and the push rod of the gas cylinder is connected with the shock-absorbing plate assembly.

[0013] Preferably, the shock-absorbing unit further comprises a pipeline assembly, the outer bellows is provided with a medium inlet and a medium outlet, and the pipeline assembly comprises a first pipeline arranged at the medium inlet and a second pipeline arranged at the medium outlet.

[0014] Preferably, the first connecting member and the second connecting member comprise knife flanges.

[0015] Preferably, the medium comprises liquid butadiene-acrylonitrile rubber or a composite rubber formed by mixing polyacrylate and silicone rubber.

[0016] The application further provides a low-temperature pump device comprising a low-temperature pump body and a shock-absorbing device as described above, the low-temperature pump body is provided with a third connecting member, and the low-temperature pump body is connected with the shock-absorbing unit through the third connecting member.

[0017] The above technical solution of the application has the following advantages compared with the prior art:

[0018] The shock-absorbing device comprises a connecting unit and a shock-absorbing unit, the shock-absorbing unit can be connected with a cryogenic pump body and other equipment through the connecting unit, when the cryogenic pump works, the vibration generated by the cryogenic pump is transmitted to the shock-absorbing device, so that the inner bellows contracts and expands, the shock-absorbing plate assembly arranged in the inner bellows and the medium filled in the cavity for shock absorption collide with each other multiple times, so as to exchange momentum and convert the vibration energy into internal energy, and the dissipated vibration is absorbed by the outer bellows, so that a better shock-absorbing effect is achieved. Specifically, when the cryogenic pump body works, the movement of the inner bellows, the medium and the shock-absorbing plate assembly can reduce the vibration of the cryogenic pump body along the axial direction, so as to effectively reduce the vibration level. The present application does not need to change the existing structure of the cryogenic pump, but sets an independent shock-absorbing device on the cryogenic pump body to achieve shock absorption, so as to ensure the close combination of the cold head and the pump body itself, without reducing the performance of the cryogenic pump itself, and without the problem of helium leakage, thereby improving the stability of production and the yield of products. BRIEF DESCRIPTION OF DRAWINGS

[0019] In order to make the content of the present application more easily understood, the present application will be further described in detail below according to specific embodiments of the present application and in conjunction with the drawings, in which.

[0020] Figure 1 is a structure schematic diagram of a first section of the best embodiment of the present application.

[0021] Figure 2 is a structure schematic diagram of a second section of the best embodiment of the present application.

[0022] Figure 3 is a structure schematic diagram of a first shock-absorbing plate of the best embodiment of the present application.

[0023] Figure 4 is a schematic diagram of a second shock-absorbing plate of the best embodiment of the present application.

[0024] Figure 5 is a sectional structure schematic diagram of a cylinder of the best embodiment of the present application.

[0025] Figure 6 is a structure schematic diagram of a cryogenic pump device of the best embodiment of the present application.

[0026] The description of the drawings is as follows: 11, first connecting piece; 12, second connecting piece; 13, third connecting piece; 2, inner bellows; 3, outer bellows; 21, first shock-absorbing plate; 22, second shock-absorbing plate; 4, cylinder; 41, push rod; 51, first pipeline; 52, second pipeline; 6, cryogenic pump body; 7, cold head. DETAILED DESCRIPTION

[0027] The application will be further described below in conjunction with the drawings and specific embodiments so that those skilled in the art can better understand the application and implement it.

[0028] Embodiment 1

[0029] With reference to Figures 1 to 6 As shown in the drawings, the application discloses a damping device for damping a cryogenic pump, comprising,

[0030] A connecting unit comprising a first connecting piece 11 and a second connecting piece 12;

[0031] A damping unit comprising an inner bellows 2 and at least one outer bellows 3, the pipe diameter of the inner bellows 2 being smaller than that of the outer bellows 3, the first connecting piece 11 and the second connecting piece 12 being arranged at two ends of the inner bellows 2 respectively, and the outer bellows 3 being sleeved on the inner bellows 2. Specifically, the outer bellows 3 is welded on the outer wall of the inner bellows 2, and since the pipe diameter of the outer bellows 3 is larger than that of the inner bellows 2, a cavity is formed between the inner bellows 2 and the outer bellows 3.

[0032] The cavity is provided with a damping medium and a damping plate assembly for damping. It should be noted that the damping plate assembly is arranged on the outer wall of the inner bellows 2 and arranged along the axial direction of the inner bellows 2. The damping medium and the damping plate assembly can weaken the axial vibration.

[0033] It can be seen that the damping device provided by the application is provided with a connecting unit and a damping unit, the damping unit can be connected to the cryogenic pump body and other equipment through the connecting unit, when the cryogenic pump works, the vibration generated by the cryogenic pump is transmitted to the damping device, so that the inner bellows contracts and expands, and the damping plate assembly arranged on the inner bellows and the damping medium filled in the cavity collide with each other multiple times, so as to exchange momentum, convert the vibration energy into internal energy, and dissipate the vibration energy, thereby achieving a better damping effect. Specifically, when the cryogenic pump body works, the movement of the inner bellows, the damping medium and the damping plate assembly can reduce the axial vibration of the cryogenic pump body, thereby effectively reducing the vibration level. The application does not need to change the existing structure of the cryogenic pump, but sets an independent damping device on the cryogenic pump body to achieve damping, so as to ensure the close combination of the cold head and the pump body itself, without reducing the performance of the cryogenic pump itself, and without the problem of helium leakage, thereby improving the stability of production and the yield of products.

[0034] Further, the damping plate assembly comprises a plurality of first damping plates 21 and a plurality of second damping plates 22 arranged along the inner bellows 2 in the axial direction, the plurality of first damping plates 21 and the plurality of second damping plates 22 are arranged alternately in sequence, and the planes where the first damping plates 21 and the second damping plates 22 are located are perpendicular to the direction where the axis of the inner bellows 2 is located. It should be particularly pointed out that the end of the damping plate assembly is the first damping plate 21, so as to ensure the overall structural stability of the damping plate assembly. The first damping plate 21 and the second damping plate 22 are annular. A plurality of mounting holes are arranged at opposite positions on the first damping plate 21 and the second damping plate 22, and the plurality of mounting holes are arranged symmetrically in the radial direction of the first damping plate 21 and the second damping plate 22. It should be noted that the plurality of mounting holes are arranged at positions close to the edge of the first damping plate 21 and the second damping plate 22, so as to facilitate assembly and make the mounting between the first damping plate 21 and the second damping plate 22 more stable and compact. The plurality of first damping plates 21 and the plurality of second damping plates 22 are locked to each other by bolts.

[0035] Further, the first damping plate 21 is provided with a plurality of first through holes, and the plurality of first through holes are arranged at intervals in the circumferential direction of the first damping plate 21. The second damping plate 22 is provided with a plurality of second through holes, and the plurality of second through holes are arranged in the circumferential direction of the second damping plate 22. The projection area of the first through hole in the axial direction of the inner bellows 2 and the projection area of the second through hole in the axial direction of the inner bellows are different.

[0036] In this embodiment, in detail, the first through hole is a honeycomb hole, and the second through hole is a circular hole, and the diameter of the circular hole is smaller than the diagonal length of the honeycomb hole. Since the projection areas of the first through hole and the second through hole are different, and the plurality of first damping plates 21 and the plurality of second damping plates 22 are arranged alternately in sequence, a plurality of smaller spaces are formed in the damping plate assembly, the medium can pass through the first through hole and the second through hole, and the medium can collide between the honeycomb hole and the circular hole multiple times, so as to exchange momentum, which is conducive to converting vibration energy into internal energy, consuming vibration energy, and dissipating the vibration absorbed by the outer bellows 3, so as to achieve a better damping effect. In this embodiment, the material of the first damping plate 21 is stainless steel, and the material of the second damping plate 22 is vulcanized rubber.

[0037] Specifically, the damping unit further comprises at least two movable connecting rods, which are arranged at two ends of the damping plate assembly and between the damping plate assembly and the outer bellows. The movable connecting rods are arranged along the direction of the axis of the inner bellows. One end of the movable connecting rod is connected to the inner wall of the outer bellows 3, and the other end is abutted against the damping plate assembly. When the cryogenic pump is working, the inner bellows 2 will shrink due to the vacuum effect. The movable connecting rods can ensure that the shape of the inner bellows 2 does not change too much, reduce the deformation of the inner bellows 2, and also play a damping role.

[0038] Further, in an embodiment, the movable connecting rod comprises a shell, an elastic member and a telescopic rod arranged in the shell. The telescopic rod is connected to the elastic member. The telescopic rod can reciprocate along its length direction under the action of external force. The shell is connected to the outer bellows 3, and the telescopic rod is connected to the damping plate assembly. The telescopic rod can reciprocate along its length direction. It should be noted that the elastic member is a spring.

[0039] Further, in another embodiment, the movable connecting rod comprises a pneumatic cylinder 4. The pneumatic cylinder 4 is installed on the outer bellows 3. The push rod 41 of the pneumatic cylinder is connected to the damping plate assembly. The pneumatic cylinder 4 is filled with inert gas. The push rod 41 of the pneumatic cylinder 4 is provided with a sealing rubber ring in the circumferential direction.

[0040] In detail, the damping unit further comprises a pipeline assembly. The outer bellows 3 is provided with a medium inlet and a medium outlet. The pipeline assembly comprises a first pipeline 51 arranged at the medium inlet. The first pipeline is used for the medium to enter the cavity. The pipeline assembly further comprises a second pipeline 52 arranged at the medium outlet. The second pipeline is used for discharging the medium.

[0041] The first pipeline 51 is provided with a first valve, and the second pipeline 52 is provided with a second valve. The medium includes but is not limited to liquid butadiene rubber, or granular composite rubber mixed by polyacrylate and silicone rubber. The medium can also use other high-damping materials. It should be noted that the particle diameter of the above-mentioned granular composite rubber is smaller than the hole diameter of the first through hole and the second through hole.

[0042] Specifically, the first connecting piece 11 and the second connecting piece 12 comprise knife-edge flanges. The size of the knife-edge flange can be selected according to actual needs. In this embodiment, the knife-edge flange adopts a standard CF10 inch flange.

[0043] It should be noted that, in order to further enhance the damping effect, the outer bellows 3 can be provided in plurality, the pipe diameters of the plurality of outer bellows 3 are sequentially increased, and the plurality of outer bellows 3 and the inner bellows 2 are coaxially arranged.

[0044] Embodiment 2

[0045] The application also discloses a cryogenic pump device, which comprises a cryogenic pump body 6 and a damping device as described above, and in detail, the cryogenic pump body 6 is provided with a third connecting piece 13, and the cryogenic pump body is connected with the damping unit through the third connecting piece 13.

[0046] Further, the third connecting piece 13 and the first connecting piece 11 of the damping device are fastened by bolts and nuts. The third connecting piece 13 is a pump body flange. The second connecting piece 12 of the damping device is connected with other devices, such as MBE devices, MOCVD, physical coating machines and other semiconductor vacuum system devices.

[0047] Further, one end of the cryogenic pump body 6 is connected with the damping device, and the other end is connected with a cold head 7.

[0048] In summary, the damping device to be protected by the application is provided with a connecting unit and a damping unit, the damping unit can be connected with the cryogenic pump body and other devices through the connecting unit, when the cryogenic pump works, the vibration generated by the cryogenic pump is conducted to the damping device, so that the inner bellows is contracted and released, and the damping plate assembly arranged in the inner bellows and the medium filled in the cavity for damping collide multiple times, so as to exchange momentum, convert the vibration energy into internal energy, and the dissipated vibration is absorbed by the outer bellows, so as to achieve a better damping effect. Specifically, when the cryogenic pump body works, the movement of the inner bellows, the medium and the damping plate assembly can reduce the vibration of the cryogenic pump body along the axial direction, so as to effectively reduce the vibration level. The application does not need to change the existing structure of the cryogenic pump, but realizes damping by arranging an independent damping device on the cryogenic pump body, so as to ensure the close combination of the cold head and the pump body itself, does not reduce the performance of the cryogenic pump itself, and does not cause the problem of helium leakage, improves the stability of production and the yield of products.

[0049] Obviously, the above embodiments are only examples for clearly illustrating the application, and are not intended to limit the embodiments. Based on the above description, those skilled in the art can make other different forms of changes or modifications. Here, all the embodiments cannot be exhausted, and the obvious changes or modifications derived therefrom are still within the protection scope of the application.

Claims

1. A vibration damping device for damping the vibration of a cryogenic pump, characterized in that: include, A connecting unit, comprising a first connector and a second connector; A vibration damping unit includes an inner corrugated pipe and at least one outer corrugated pipe. The diameter of the inner corrugated pipe is smaller than the diameter of the outer corrugated pipe. A first connector and a second connector are respectively disposed at both ends of the inner corrugated pipe. The outer corrugated pipe is sleeved on the inner corrugated pipe. A vibration damping medium and a vibration damping plate assembly are disposed between the inner corrugated pipe and the outer corrugated pipe. The vibration damping plate assembly is disposed along the axial direction of the inner corrugated pipe. The damping plate assembly includes a plurality of first damping plates and a plurality of second damping plates arranged along the axial direction of the inner bellows. The plurality of first damping plates and the plurality of second damping plates are arranged alternately in sequence. The plane in which the first damping plates and the second damping plates are located is perpendicular to the direction in which the axis of the inner bellows is located. The first damping plate is provided with a plurality of first through holes, and the second damping plate is provided with a plurality of second through holes. The projected area of ​​the first through holes along the axial direction of the inner bellows and the projected area of ​​the second through holes along the axial direction of the inner bellows are different.

2. The shock absorption device according to claim 1, characterized in that: The damping unit further includes at least two movable links, which are respectively disposed at both ends of the damping plate assembly and located between the damping plate assembly and the outer bellows. The movable links are arranged along the direction of the axis of the inner bellows.

3. A shock-absorbing device according to claim 2, characterized in that: The movable link includes a housing and an elastic element and a telescopic rod disposed within the housing. The telescopic rod is connected to the elastic element, the housing is connected to the outer bellows, and the telescopic rod is connected to the shock-absorbing plate assembly. The telescopic rod is capable of reciprocating along its length.

4. A shock-absorbing device according to claim 2, characterized in that: The movable linkage includes a cylinder, which is mounted on the outer bellows, and the cylinder's push rod is connected to the shock absorber assembly.

5. A shock-absorbing device according to claim 1, characterized in that: The vibration damping unit also includes a pipe assembly, on which the outer corrugated pipe is provided with a medium inlet and a medium outlet. The pipe assembly includes a first pipe disposed at the medium inlet and a second pipe disposed at the medium outlet.

6. A shock-absorbing device according to claim 1, characterized in that: The first and second connectors include knife-edge flanges.

7. A shock-absorbing device according to claim 1, characterized in that: The medium includes liquid nitrile rubber or a composite rubber made of polyacrylate and silicone rubber.

8. A cryogenic pump device, characterized in that: The device includes a cryogenic pump body and a vibration damping device as described in any one of claims 1-7, wherein the cryogenic pump body is provided with a third connector, and the cryogenic pump body is connected to the vibration damping unit through the third connector.

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