A cryopump with adjustable gas pumping speed

Abstract

The application discloses a low-temperature pump with adjustable gas pumping speed, which comprises a pump body assembly, a control assembly and a field generator. The pump body assembly is provided with a pump cavity with a pumping opening. The control assembly is arranged in the pump cavity and comprises a field induction part and a throttling part connected to the field induction part, and the field induction part is connected to the pump body assembly. The field generator is arranged in the pump body assembly and used for emitting a control field to the field induction part. The control field can make the field induction part change shape, and the change of the shape of the field induction part can make the throttling part change position relative to the pump body assembly, so that the fluid flow rate flowing into the pump cavity can be changed. The low-temperature pump can change the fluid flow rate of the pump cavity through the field generator and the field induction part, and has a simple structure.

Description

Technical Field

[0001] This invention relates to the field of vacuum pump technology, and in particular to a cryogenic pump with adjustable gas pumping speed. Background Technology

[0002] Cryogenic pumps are vacuum-generating devices that utilize low-temperature surfaces to condense, adsorb, and trap gas molecules, thereby creating a vacuum environment. They offer advantages such as high pumping speed, large gas capacity, high ultimate vacuum, no moving parts at the pumping interface, and clean, oil-free operation, making them widely used in semiconductor chip fabrication equipment (such as ion implanters and PVD). Existing cryogenic pumps often incorporate structures to control the pumping speed to achieve optimal performance for different processes. In some embodiments, pumping speed control can be achieved by adding a flow control valve to the pump's suction end; however, this type of cryogenic pump is bulky, costly, and has a limited flow control range. In another embodiment, a louver-like structure with multiple movable blades can be incorporated into the pump chamber. These blades are driven to open and close, altering the effective cross-sectional area of ​​the pump chamber and thus changing the fluid velocity. The louver structure, integrated within the pump chamber, is relatively small and offers a wider flow control range. However, these cryogenic pumps require a drive power source and a mechanical transmission mechanism, resulting in a complex structure and a higher failure rate. Summary of the Invention

[0003] This invention aims to solve at least one of the technical problems existing in the prior art. To this end, this invention proposes a cryogenic pump with adjustable gas pumping speed, which achieves the change of fluid flow rate in the pump chamber through a field generator and a field sensing element, and has a simple structure.

[0004] According to an embodiment of the present invention, a cryogenic pump with adjustable gas pumping speed includes: a pump body assembly having a pump chamber having a suction opening; a control assembly disposed in the pump chamber, the control assembly including a field sensor and a throttling device, the throttling device being connected to the field sensor and the field sensor being connected to the pump body assembly; and a field generator disposed in the pump body assembly and used to emit a control field to the field sensor; wherein the control field can cause the field sensor to change shape, and when the field sensor changes shape, it can cause the throttling device to undergo a positional change relative to the pump body assembly, so as to change the flow rate of the fluid flowing into the pump chamber.

[0005] According to an embodiment of the present invention, an adjustable gas pumping speed cryogenic pump has at least the following beneficial effects: The above-mentioned cryogenic pump generates a control field through a field generator, and the field sensor is a field-sensitive element. Under the action of the control field, the field sensor changes shape, thereby causing the throttling element to change position and altering the effective cross-sectional area of ​​the pump cavity, thus changing the fluid flow rate. Since the change in fluid flow rate is achieved using a control field, there are fewer mechanical mechanisms, no need for motor or cylinder drive, the mechanism is small in size, and the structure is simple. Furthermore, the control field is a non-contact control method, eliminating the need for mechanical transmission mechanisms and avoiding sealing problems caused by mechanical transmission mechanisms. It is also easy to improve existing cryogenic pumps and has good compatibility.

[0006] According to some embodiments of the present invention, the field sensing element is a shape memory alloy.

[0007] According to some embodiments of the present invention, the field generator is at least one of a temperature regulator, a magnetic field generator, and an electric field generator.

[0008] According to some embodiments of the present invention, multiple control components are provided and arranged circumferentially around a predetermined central axis. The multiple control components are opposite to the suction opening. One end of the multiple field sensors is connected together, and the throttling device is connected to the other end of the corresponding field sensor.

[0009] According to some embodiments of the present invention, the other end of the plurality of field sensors is connected to a bracket, and the plurality of field sensors are connected to the pump body assembly through the bracket.

[0010] According to some embodiments of the present invention, the pump body assembly includes a shield and a primary flow guide baffle, the shield forming the pump chamber, the primary flow guide baffle being disposed at the suction opening, and the bracket being fixed to the shield or the primary flow guide baffle.

[0011] According to some embodiments of the present invention, a chiller is further included, the chiller being disposed in the pump body assembly, the chiller being provided with a cold head, the cold head being housed in the pump chamber, the pump body assembly including a primary flow guide baffle being disposed at the suction opening, and the control component being disposed between the primary flow guide baffle and the cold head.

[0012] According to some embodiments of the present invention, the pump body assembly includes a primary flow guide baffle, which is disposed at the suction opening. Multiple control components are provided, and the field sensing elements of the multiple control components are individually fixed to the primary flow guide baffle.

[0013] According to some embodiments of the present invention, the primary flow guide baffle includes a plurality of plates, and a flow guide channel is formed between the plates. The field sensing element and the throttling element are disposed in the flow guide channel.

[0014] According to some embodiments of the present invention, the control component is disposed at the suction opening to form a primary flow guide baffle.

[0015] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0016] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which:

[0017] Figure 1 This is a cross-sectional view of an embodiment of the present invention;

[0018] Figure 2 This is a schematic diagram of the structure of the field sensing element after it is excited by the control field according to an embodiment of the present invention;

[0019] Figure 3 This is a top view of a single control component according to an embodiment of the present invention;

[0020] Figure 4 This is a top view of the combined and connected multiple control components according to an embodiment of the present invention;

[0021] Figure 5 A cross-sectional view of the control component of this invention, showing an alternative installation method.

[0022] Figure 6 for Figure 5 Enlarged view of point A;

[0023] Figure 7 for Figure 5 A schematic diagram of the structure of the field sensing element in the embodiment shown after being excited by the control field;

[0024] Figure label:

[0025] Pump body assembly 100, pump chamber 110, suction opening 111, shield 120, primary flow guide baffle 130;

[0026] Control component 200, field sensor 210, throttling device 220;

[0027] Bracket 300;

[0028] Refrigeration unit 400, cold head 410. Detailed Implementation

[0029] Embodiments of the present invention are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0030] In the description of this invention, it should be understood that the orientation descriptions, such as up, down, front, back, left, right, etc., are based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting this invention.

[0031] In the description of this invention, "several" means one or more, "more than" means two or more, "greater than," "less than," and "exceeding" are understood to exclude the stated number, while "above," "below," and "within" are understood to include the stated number. The use of "first" and "second" in the description is merely for distinguishing technical features and should not be construed as indicating or implying relative importance, or implicitly indicating the number of indicated technical features, or implicitly indicating the order of the indicated technical features.

[0032] In the description of this invention, unless otherwise explicitly defined, terms such as "setting," "installing," and "connecting" should be interpreted broadly, and those skilled in the art can reasonably determine the specific meaning of the above terms in this invention in conjunction with the specific content of the technical solution.

[0033] Reference Figures 1 to 2 A cryogenic pump with adjustable gas pumping speed includes a pump body assembly 100, a control assembly 200, and a field generator (not shown in the figure). The pump body assembly 100 has a pump chamber 110 with a suction opening 111. The control assembly 200 is disposed in the pump chamber 110 and includes a field sensor 210 and a throttling element 220. The throttling element 220 is connected to the field sensor 210, and the field sensor 210 is connected to the pump body assembly 100. The field generator is disposed in the pump body assembly 100 and is used to emit a control field to the field sensor 210. The control field causes the field sensor 210 to change shape, and this change in shape causes the throttling element 220 to shift position relative to the pump body assembly 100, thereby altering the flow rate of the fluid flowing into the pump chamber 110.

[0034] The aforementioned cryogenic pump generates a control field through a field generator. The field sensor 210 is a field-sensitive element. Under the action of the control field, the field sensor 210 changes shape, thereby causing the throttling element 220 to change position and altering the effective cross-sectional area of ​​the pump chamber 110, thus changing the fluid flow rate. Because the fluid flow rate is changed using a control field, there are fewer mechanical mechanisms, no need for motor or cylinder drive, resulting in a small and simple structure. Furthermore, the control field is non-contact, eliminating the need for mechanical transmission mechanisms and avoiding sealing issues caused by mechanical transmission mechanisms. It is also easy to improve upon existing cryogenic pumps, offering good compatibility.

[0035] In the embodiments, the field sensing element 210 can be specifically filamentous, thin strip, or columnar, and the throttling element 220 can be fan-shaped or rectangular, etc. It can be imagined that the specific shapes of the field sensing element 210 and the throttling element 220 can be configured according to the actual situation and are not limited to the above-described embodiments.

[0036] In this embodiment, the field sensing element 210 is a shape memory alloy. The shape memory alloy deforms under the excitation of its corresponding control field, and when the control field returns to its original state, the shape memory alloy recovers its original shape, thus achieving the function of controlling the shape change of the field sensing element 210 through the control field. The field sensing element 210 uses a shape memory alloy, which has a simple structure and is easy to implement. Specifically, the shape memory alloy can be one or more of Ni-Ti, Ni-Ti-Fe, Ni-Ti-Cr, NiFe-Mn-based, and Ni-Ti-Nb-Fe.

[0037] Of course, it is conceivable that in some embodiments, the field sensing element 210 is not limited to using shape memory alloy. For example, in other embodiments, the field sensing element 210 may include two hinged parts, with the throttling element 220 connected to one of the parts. This part is provided with a magnet, and the field generator is an electromagnet. When the electromagnet is activated, it attracts this part to swing, thereby realizing the shape change of the field sensing element 210 and the position change of the throttling element 220.

[0038] In this embodiment, the field generator is at least one of a temperature controller, a magnetic field generator, and an electric field generator. Field generators of the types described above are readily available and easy to implement. It is understood that the specific type of field generator used depends on the type of the specific field sensing element 210. For example, if the field sensing element 210 is made of a temperature-sensitive shape memory alloy, then the field generator should specifically be a temperature controller. It is conceivable that when the field sensing element 210 can sense more than one control field, the field generator can be a structure capable of generating multiple control fields; that is, it can be a structure combining at least two of the temperature controller, magnetic field generator, and electric field generator.

[0039] In the embodiments, the temperature controller is specifically a device capable of lowering or raising the temperature, such as a heating wire, a semiconductor cooler, etc., thereby generating a temperature field; the magnetic field generator is specifically a device capable of generating a magnetic field, such as a coil; the electric field generator is specifically a device capable of generating an electric field, such as two opposing conductive plates and a battery that provides electrical energy.

[0040] Reference Figure 3 and Figure 4 In this embodiment, multiple control components 200 are arranged circumferentially around a predetermined central axis. These control components 200 are opposite to the suction opening 111, and one end of multiple field sensors 210 are connected together. A throttling element 220 is connected to the other end of the corresponding field sensor 210. This structure is relatively symmetrical and reasonable, and the control range of the multiple control components 200 is also relatively large. The predetermined central axis can specifically be the pump body assembly 100, the pump chamber 110, or the central axis of the pump chamber 110.

[0041] It is conceivable that the control component 200 is not limited to multiple sets; for example, in some embodiments, the control component 200 may be provided with only one set.

[0042] In this embodiment, the other end of each of the multiple field sensors 210 is connected to a bracket 300, and the multiple field sensors 210 are connected to the pump assembly 100 via the bracket 300. In this structure, multiple control components 200 are uniformly mounted and fixed via the bracket, facilitating assembly. Specifically, in this embodiment, the pump assembly 100 includes a shield 120 and a primary flow guide baffle 130. The shield 120 forms a pump chamber 110, and the primary flow guide baffle 130 is disposed at the suction opening 111. The bracket 300 is fixed to either the shield 120 or the primary flow guide baffle 130. In this embodiment, the bracket 300 can be fixed to the shield 120 or the primary flow guide baffle 130 by welding, riveting, adhesive bonding, or bolting.

[0043] In this embodiment, a chiller 400 is also included. The chiller 400 is disposed within the pump body assembly 100 and has a cold head 410 housed in the pump chamber 110. A control component 200 is disposed between the primary flow guide baffle 130 and the cold head 410. The control component 200 is positioned at this location, which is reasonable and allows for flow rate control after the fluid passes through the primary flow guide baffle 130 and before reaching the cold head 410.

[0044] Reference Figures 5 to 7In other embodiments, multiple control components 200 are provided, and the field sensing elements 210 of each of the multiple control components 200 are individually fixed to the primary flow guide baffle 130. With the above structure, multiple control components 200 are provided and each is individually attached to the primary flow guide baffle 130, thus eliminating the need for mounting brackets, simplifying the internal structure of the cryogenic pump, and reducing the number of parts. Specifically, the field sensing elements 210 can be fixed to the primary flow guide baffle 130 by welding, riveting, adhesive bonding, or bolting.

[0045] In this embodiment, the primary flow guide baffle 130 includes multiple plates forming a flow guide channel, and the field sensor 210 and the throttling device 220 are disposed in the flow guide channel. With the above structure, the field sensor 210 and the throttling device 220 are housed within the flow guide channel, resulting in a more compact structure.

[0046] In some embodiments not shown in the figures, the control component 200 is disposed at the suction opening 111 to form a primary flow guide baffle. By directly using the control component 200 as the primary flow guide baffle, the cryogenic pump structure is simpler and has fewer parts.

[0047] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0048] The embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the present invention is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of the present invention.

Claims

1. A cryogenic pump with adjustable gas pumping speed, characterized in that, include: The pump body assembly (100) is provided with a pump chamber (110) having a suction opening (111). A control component (200) is disposed in the pump chamber (110). The control component (200) includes a field sensor (210) and a throttling device (220). The throttling device (220) is connected to the field sensor (210), and the field sensor (210) is connected to the pump body assembly (100). A field generator is disposed in the pump body assembly (100) and is used to emit a control field to the field sensor (210); The control field energy causes the field sensor (210) to change shape. When the field sensor (210) changes shape, it causes the throttling device (220) to change position relative to the pump body assembly (100), so that the flow rate of the fluid flowing into the pump chamber (110) can be changed. Multiple control components (200) are arranged circumferentially around a predetermined central axis. Multiple control components (200) are opposite to the suction opening (111). One end of multiple field sensors (210) is connected together, and the throttling device (220) is connected to the other end of the corresponding field sensor (210).

2. The cryogenic pump with adjustable gas pumping speed according to claim 1, characterized in that: The field sensing element (210) is a shape memory alloy.

3. A cryogenic pump with adjustable gas pumping speed according to claim 1 or 2, characterized in that: The field generator is at least one of a temperature controller, a magnetic field generator, and an electric field generator.

4. A cryogenic pump with adjustable gas pumping speed according to claim 1, characterized in that: The other end of the plurality of field sensors (210) is connected to a bracket (300), and the plurality of field sensors (210) are connected to the pump body assembly (100) through the bracket (300).

5. A cryogenic pump with adjustable gas pumping speed according to claim 4, characterized in that: The pump body assembly (100) includes a shield (120) and a primary flow guide baffle (130). The shield (120) forms the pump chamber (110). The primary flow guide baffle (130) is disposed at the suction opening (111). The bracket (300) is fixed to the shield (120) or the primary flow guide baffle (130).

6. A cryogenic pump with adjustable gas pumping speed according to claim 1, characterized in that: It also includes a chiller (400), which is disposed in the pump body assembly (100). The chiller (400) is provided with a cold head (410), which is housed in the pump chamber (110). The pump body assembly (100) includes a primary flow guide baffle (130), which is disposed at the suction opening (111). The control component (200) is disposed between the primary flow guide baffle (130) and the cold head (410).

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