A casing cooling structure and a cooling method of an air-floating motorized spindle

Abstract

The present application relates to the technical field of ultra-precision machining equipment, and particularly relates to a shell cooling structure and a cooling method of an air-floating electric spindle, which comprises a shell, a motor and an air-floating bearing system are arranged in the shell, a plurality of groups of cooling pipes are arranged in the shell, each group of the cooling pipes comprises an inlet pipe and an outlet pipe, a water inlet collecting tank and a water outlet collecting tank are arranged on the shell and are respectively communicated with one end of each inlet pipe and each outlet pipe, and a backflow elbow structure is further arranged on the shell and is used for connecting each inlet pipe with each corresponding outlet pipe at the other end of the shell. The cooling liquid is distributed and collected in the water inlet collecting tank, enters each inlet pipe in parallel, is folded back into each outlet pipe through the backflow elbow structure, and is then discharged in the water outlet collecting tank. The present application realizes the centralized distribution and collection, parallel flow and folding circulation of the cooling liquid, makes the temperature distribution of the shell uniform, has small flow resistance, is convenient for external pipeline connection, and effectively improves the machining precision and running stability of the air-floating electric spindle.

Description

Technical Field

[0001] This invention relates to the field of ultra-precision machining equipment technology, and in particular to a housing cooling structure and cooling method for an air-bearing electric spindle, which is especially suitable for temperature control management of air-bearing electric spindles in fields such as semiconductor processing and precision manufacturing. Background Technology

[0002] Air-bearing electric spindles are widely used in semiconductor processing, precision manufacturing, and other fields due to their advantages such as cleanliness, non-contact operation, and low friction. Air-bearing electric spindles primarily rely on air bearings to achieve high-speed, non-contact support for spindle operation. Air bearings typically utilize high-pressure air to form a micron-sized air film. During high-speed rotation, the gas shear friction generates a large amount of heat, and the motor operation also introduces significant heat. If heat dissipation is not timely and effective, the spindle temperature will rise excessively, leading to thermal deformation, reduced machining accuracy, and even affecting the stability and lifespan of the air bearings.

[0003] In existing technologies, the cooling of electric spindles is mainly achieved by setting cooling channels within the housing. A common cooling structure involves creating several axial cooling channels within the housing, with coolant flowing in from one end and out from the other, cooling both the housing and the motor. However, traditional unidirectional straight-through channels have the following drawbacks: First, the temperature of the coolant gradually increases during the flow process, resulting in a significant temperature gradient in the housing. There is a temperature difference between the side of the housing that is cooled first and the side that is cooled later, which affects the uniformity of the temperature distribution of the whole machine. This affects the stability of the micron-level air film between the air bearing and the spindle rotor, and consequently affects the machining accuracy of the air-bearing electric spindle.

[0004] Secondly, the motor is the main heat source of the air-bearing electric spindle. Existing cooling channels are often evenly arranged without enhanced cooling for the motor area, resulting in insufficient heat dissipation in the motor part, which affects the working efficiency and service life of the motor.

[0005] Third, the unidirectional straight flow channel has a long stroke and high flow resistance, which places high demands on the water pump equipment. The introduction of a high-lift water pump is prone to vibration, affecting the operational stability of the air-float electric spindle.

[0006] Fourth, the inlet and outlet pipes of the existing cooling structure are usually distributed at different ends of the shell, which increases the complexity of external pipe connections and layout difficulty. Summary of the Invention

[0007] To address the technical deficiencies mentioned in the background section, the present invention aims to provide a cooling structure and method for the housing of an air-bearing electric spindle. By optimizing the layout of the cooling pipes and the water circulation method, uniform cooling is achieved throughout the entire length of the housing, and heat dissipation is enhanced for the motor, the main heat source, thereby effectively reducing the overall temperature rise of the air-bearing electric spindle and improving machining accuracy and operational stability.

[0008] To achieve the above objectives, the present invention adopts the following technical solution: A housing cooling structure for an air-bearing electric spindle includes a housing, in which a motor and an air-bearing system are disposed. The housing has a first end and a second end in the axial direction, the first end being the cutter head side and the second end being the motor side. The housing is provided with several sets of cooling pipes, each set of cooling pipes including at least one liquid inlet pipe and at least one liquid outlet pipe, both of which extend along the axial direction of the housing. The housing is provided with an inlet water collection tank and a drain water collection tank. The inlet water collection tank is connected to one end of each liquid inlet pipe and is used to centrally distribute the coolant to each liquid inlet pipe. The drain water collection tank is connected to one end of each liquid outlet pipe and is used to centrally collect the return coolant. Preferably, the inlet water collection tank and the outlet water collection tank are both located at the second end of the shell, and the inlet water collection tank and the outlet water collection tank are isolated from each other.

[0009] Preferably, the water inlet collection tank is provided with a water inlet, and the water outlet collection tank is provided with a water outlet, both of which are located at the second end of the shell.

[0010] Preferably, the housing is further provided with a reflux turning structure, which is used to connect each inlet pipe to the corresponding outlet pipe at the other end of the housing, so that the coolant flows back from the inlet pipe through the reflux turning structure into the outlet pipe.

[0011] Preferably, the reflux turning structure is disposed at the first end of the housing, and the reflux turning structure is a U-shaped reflux turning structure.

[0012] Preferably, the number of cooling pipes is four or more, and the cooling pipes in each group are distributed on the cross-section of the shell as follows: at least two groups are located in the corner region of the cross-section of the shell, and at least two groups are located in the side region of the cross-section of the shell.

[0013] Preferably, in each group of cooling pipes, the inlet pipe and the outlet pipe are arranged adjacent to each other on the cross-section of the shell; both the inlet pipe and the outlet pipe are located inside the wall of the shell.

[0014] Preferably, it further includes a flow regulating device and / or a temperature detection device, wherein the flow regulating device is disposed on the coolant inflow path, and the temperature detection device is disposed inside or on the housing, for adjusting the coolant flow rate according to the real-time temperature feedback signal inside the housing.

[0015] A method for cooling the housing of an air-bearing electric spindle, employing the aforementioned housing cooling structure for the air-bearing electric spindle, includes the following steps: a. Coolant enters the water inlet collection tank provided on the housing; b. After the coolant is collected in the water inlet tank, it is distributed in parallel into several inlet pipes and flows from one end of the housing to the other along the axial direction of the housing. During the flow, the coolant cools the motor and air bearing system inside the housing. c. After the coolant flows to the other end of the housing, it is turned back by the reflux turning structure provided on the housing and enters several outlet pipes; d. The coolant flows back from the other end to the first end along the outlet pipe, continuing to cool the housing during the backflow process; e. After the coolant flows back to the second end of the housing, it collects in the drain collection tank and is discharged from the housing.

[0016] Preferably, the coolant flows in parallel and in opposite directions in the inlet pipe and the outlet pipe.

[0017] In summary, the beneficial effects of the present invention are as follows: 1. This invention achieves centralized distribution and collection of coolant by setting an inlet water collection tank and a drain water collection tank at the tail end of the housing. The inlet water collection tank allows the coolant from the inlet to be fully mixed and pressure balanced within the cavity before being distributed into each inlet pipe, ensuring consistent water pressure and flow rate at the inlet of each inlet pipe. At the same time, the drain water collection tank allows the coolant returning from each outlet pipe to be collected within the cavity and discharged centrally, avoiding the problem of poor backflow caused by pressure differences at the outlet of each outlet pipe. In addition, the design of the two collection tanks is mutually isolated to ensure that the inlet and outlet water do not crossflow, ensuring the uniqueness and correctness of the coolant flow direction.

[0018] 2. This invention provides parallel, folded-back cooling pipes extending axially within the shell wall thickness. The inlet and outlet pipes are arranged in opposite directions along the axial direction. The coolant is diverted from the tail end of the shell into all the inlet pipes, and after folding back at the front end, it flows back and collects from the outlet pipe before being discharged. This achieves sufficient cooling of the shell and internal heat-generating components, resulting in a more uniform overall temperature distribution, ensuring equal air film thickness, and ensuring uniform load-bearing capacity and stiffness of the air bearing system.

[0019] 3. The present invention adopts a parallel flow channel design, which distributes the coolant flow evenly in each cooling circuit, resulting in a simple flow path and low flow resistance. This avoids the problem of needing a high-lift water pump due to the difference in flow resistance in series flow channels, thereby reducing the generation of additional vibration. In addition, the inlet and outlet are concentrated at the same end of the shell, which greatly simplifies the external pipeline layout and improves the operating accuracy and stability of the air-float electric spindle.

[0020] 4. The cooling pipes of the present invention are evenly distributed in the cross-section of the shell, with one set at each of the four corners and one set on each of the left and right sides, covering both the corner and central areas, eliminating cooling dead zones and achieving comprehensive and uniform cooling of the shell; at the same time, in the shell section where the motor is located, the liquid inlet pipe and the liquid outlet pipe are arranged alternately. This layout utilizes the large temperature difference to achieve more efficient heat exchange in the area where the motor is located, thereby achieving enhanced cooling of the motor area. Attached Figure Description

[0021] Figure 1 This is an overall assembly schematic diagram of the cooling structure of the air-float electric spindle housing of the present invention; Figure 2 This is a top view of the cooling structure of the air-float electric spindle housing of the present invention; Figure 3 yes Figure 2 A cross-sectional view of the AA plane; Figure 4 yes Figure 2 A cross-sectional view of the BB plane; Figure 5 yes Figure 2 A sectional view of the C-plane; Figure 6 This is an exploded view of the shell structure in this invention; Figure 7 This is a schematic diagram of the air bearing system in this invention; Figure 8 This is a schematic diagram of the cooling pipe structure in this invention.

[0022] Explanation of the reference numerals in the figure: 1. Housing; 2. Rear end cover; 3. Motor; 4. Cutter head; 5. Radial bearing; 6. Thrust bearing; 7. Main spindle rotor; 8. Sleeve; 9. Thrust spacer ring; 10. Cooling pipe; 101. Liquid inlet pipe; 102. Liquid outlet pipe; 11. Water inlet collection tank; 12. Water inlet; 13. Drainage collection tank; 14. Water outlet; 15. Return flow turning structure. Detailed Implementation

[0023] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention are within the scope of protection of the present invention.

[0024] Those skilled in the art should understand that, in the disclosure of this invention, the terms "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicate the orientation or positional relationship 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, the above terms should not be construed as limiting this invention.

[0025] In the description of this invention, the use of terms such as "a number" means one or more, with "more than" meaning two or more. Terms like "greater than," "less than," and "exceeding" are understood to exclude the stated number, while terms like "above," "below," and "within" are understood to include the stated number. The use of terms like "first," "second," and "third" is merely for distinguishing technical features and should not be construed as indicating or implying relative importance, the number of indicated technical features, or the sequential relationship between indicated technical features.

[0026] The following is in conjunction with the appendix Figure 1-8 The embodiments of the cooling structure and cooling method for the housing of an air-floating electric spindle of the present invention will be described in further detail.

[0027] A housing cooling structure for an air-floating electric spindle, such as Figure 1 , 6 As shown in Figure 7, the device includes a housing 1, which houses components such as a motor 3 and an air bearing system. The first end (front end) of the housing 1 is the cutter head side (right side in the figure), and a cutter head 4 is mounted thereon; the second end (tail end) is the motor side (left side in the figure), and a motor 3 is mounted thereon.

[0028] Specifically, the housing 1 can be made of metal materials such as aluminum alloy, copper alloy, and stainless steel, or other alloy materials with good thermal conductivity. A rear end cover 2 is provided at the tail end of the housing 1. The air bearing system includes a radial bearing 5, a thrust bearing 6, a main shaft rotor 7, a sleeve 8, and a thrust spacer ring 9. The radial bearing 5 is located on the radially outer side of the main shaft rotor 7, and the thrust bearings 6 are respectively arranged on the front and rear sides of the thrust plate of the main shaft rotor 7 along the axial direction, together achieving contactless support for the main shaft rotor 7 and ensuring its high-speed stable rotation.

[0029] In some implementations, such as Figure 4 , 5 As shown in Figure 8, a water inlet collection tank 11 and a water outlet collection tank 13 are provided inside the rear end of the housing 1 (away from the cutter head 4). Both the water inlet collection tank 11 and the water outlet collection tank 13 are located close to the motor 3 and are isolated from each other to ensure that the water inlet and outlet do not crossflow and to reduce the impact of fluid disturbance on the accuracy of the cutter head 4. The water inlet collection tank 11 is provided with a water inlet 12, and the water outlet collection tank 13 is provided with a water outlet 14. Both the water inlet 12 and the water outlet 14 are located at the rear end of the housing 1 for easy connection to external pipelines.

[0030] Specifically, six sets of cooling pipes 10 are provided inside the shell 1. Each set of cooling pipes 10 includes one inlet pipe 101 and one outlet pipe 102. The six sets of cooling pipes 10 are distributed on the cross-section of the shell 1 as follows: four sets of cooling pipes 10 are located at the four corners of the cross-section of the shell 1, and two additional sets of cooling pipes 10 are located at the middle of the left and right sides of the cross-section of the shell 1. The six sets of cooling pipes 10 form a uniform distribution on the cross-section of the shell 1, covering both the corner and middle areas, eliminating cooling dead zones. At the same time, the six sets of cooling pipes 10 are symmetrically distributed on both sides of the cross-section of the shell 1 to ensure that the temperature distribution after cooling is also symmetrical. In each set of cooling pipes 10, the inlet pipe 101 and the outlet pipe 102 are arranged adjacent to each other on the cross-section of the shell 1, preferably two pipes are arranged side by side with an appropriate distance. All twelve cooling pipes 10 are set inside the wall thickness of the shell 1, without occupying the external space of the shell 1, which is conducive to the miniaturization and compact design of the overall structure.

[0031] It should be noted that the relative positions of the inlet pipe 101 and the outlet pipe 102, the inlet water collection tank 11 and the drain water collection tank 13 can be interchanged. That is, the inlet water collection tank 11 can be closer to the cutter head 4 and the drain water collection tank 13 can be closer to the rear end cover 2. Similarly, the drain water collection tank 13 can also be closer to the cutter head 4 and the inlet water collection tank 11 can be closer to the rear end cover 2. This embodiment does not impose any restrictions.

[0032] Meanwhile, the cooling channels inside the shell 1 can be of any shape, not limited to circular, elliptical, square, or other irregular cross-sections. The cross-section of the cooling pipe 10 can be set to the same cross-sectional area, or it can be set to different cross-sectional areas according to the cooling requirements, but it is necessary to ensure that the cooling effect is symmetrical along the central axis of the shell 1.

[0033] In some implementations, such as Figure 3 , 4As shown in Figure 8, the tail end of each inlet pipe 101 is connected to the inlet water collection tank 11, and the tail end of each outlet pipe 102 is connected to the drain water collection tank 13. A return flow turning structure 15 (a U-shaped turning head in this embodiment) is provided at the front end of the housing 1 to connect each inlet pipe 101 with the corresponding outlet pipe 102 at the front end of the housing 1, so that the coolant flows back from the inlet pipe 101 through the return flow turning structure 15 into the outlet pipe 102.

[0034] Specifically, the reflux turning structure 15 can use an independent U-shaped turning joint to connect each group of inlet and outlet pipes 102, which provides better sealing performance and avoids cross-flow between groups.

[0035] It should be noted that the cooling medium can be water-based coolant, oil-based coolant, or other cooling media with good thermal conductivity.

[0036] In this invention, the cooling pipe 10 and the water collection tank can be processed using various techniques: Method 1: During the machining of the shell 1, the cooling pipe 10 channel and the water collection tank cavity are drilled along the axial direction, and then the cooling pipe 10 is inserted into the channel and fixed by brazing, pressing or bonding.

[0037] Method 2: During the casting of shell 1, the cooling pipe 10 channels and the water collection tank cavity are directly cast as a single piece as part of shell 1. Alternatively, shell 1 can also be manufactured using other processing methods that enable one-piece molding, such as 3D printing.

[0038] Method 3: A cooling channel groove is formed between the inner shell and the outer shell of the housing 1 by milling, and then the inner shell and the outer shell are assembled and sealed to form a complete cooling pipe 10 channel.

[0039] Method 4: When there is insufficient space in the housing 1, a flow channel can be formed by slotting at the corresponding position of the other housing or the rear end cover 2 through cooperation with another housing or the rear end cover 2, and the seal can be ensured by O-rings, welding or glue sealing; the rear end cover 2 can also be replaced with any other component that can help form the channel.

[0040] In addition, the processing of the return flow turning structure 15 can be achieved by hollowing out the shell 1 to match the plug.

[0041] To further enhance the intelligent temperature control of the electric spindle, a flow regulating valve and a temperature sensor are added at the front end of the water inlet 12. The temperature sensor is located inside the housing 1 and is used to detect the real-time temperature inside the housing 1. Based on the temperature signal fed back by the temperature sensor, the flow regulating valve is controlled to adjust the flow rate and / or temperature of the coolant, thereby achieving intelligent temperature control. When the temperature inside the housing 1 is detected to be too high, the coolant flow rate is increased or the coolant temperature is decreased; when the temperature inside the housing 1 is detected to be too low, the coolant flow rate is decreased or the coolant temperature is increased.

[0042] Working principle of the invention: During operation, an external water pump delivers coolant from inlet 12 into inlet water collection tank 11. After the coolant pressure in inlet water collection tank 11 is equalized, it is simultaneously distributed to all inlet pipes 101. The coolant flows along inlet pipes 101 from the tail end to the front end of housing 1, absorbing heat from housing 1 and internal motor 3 and bearings during the process, completing the first heat exchange. When the coolant in all inlet pipes 101 reaches the front end, it enters the return flow turning structure 15 and flows back into the corresponding outlet pipe 102. Subsequently, the coolant flows back along outlet pipes 102 from the front end to the tail end of housing 1, continuing to absorb heat from housing 1 during the process, completing the second heat exchange. Finally, the coolant in all outlet pipes 102, after absorbing heat, collects in drain water collection tank 13 and is then discharged from outlet 14 into housing 1, completing one cooling cycle.

[0043] In some embodiments, the present invention also provides a method for cooling the housing 1 of an air-bearing electric spindle, comprising the following steps: a. Coolant enters the interior of housing 1 through inlet 12 and flows into water inlet collection tank 11 located at the tail end of housing 1; b. After the coolant is collected and pressure is balanced in the inlet water collection tank 11, it is evenly and parallelly distributed into the six inlet pipes 101. The coolant flows from the tail end to the front end (direction of the cutter head 4) along the axial direction of the housing 1. During the flow, it flows through the area where the motor 3 is located and the area where the air bearing system (radial bearing 5, thrust bearing 6) is located, cooling the motor 3 and the bearing system. c. When the coolant flows to the front end of the housing 1 (side of the cutter head 4), it is turned back into the six outlet pipes 102 through the return turning structure 15 (U-shaped turning head) set on the side of the cutter head 4. d. The coolant flows back from the front end to the rear end (motor 3 side) along the outlet pipe 102, and continues to cool the housing 1 during the backflow process; e. The coolant in the inlet pipe 101 and the coolant in the outlet pipe 102 flow in parallel and in opposite directions within the housing 1. The countercurrent flow of hot and cold fluids helps to reduce the temperature gradient along the axial direction of the housing 1, making the temperature rise of the housing 1 more uniform. f. Finally, the coolant flows back to the tail end of the housing 1, collects in the drain collection tank 13, and then flows out of the housing 1 through the outlet 14, completing the entire cooling cycle.

[0044] Specifically, using the above-mentioned cooling method, all cooling pipes 10 operate independently and in parallel. The coolant enters each inlet pipe 101 at its initial cooling temperature, avoiding the problems of coolant temperature rise along the flow path and large temperature differences between the left and right sides of the casing 1, which are common in unidirectional straight-through channels. Simultaneously, the low-temperature coolant in the inlet pipe 101 and the already heated coolant in the outlet pipe 102 flow in opposite directions and in parallel, balancing the overall temperature inside the casing 1, further reducing the temperature gradient, and making the overall temperature distribution of the casing 1 more uniform. Moreover, due to the parallel flow channels, the flow path is short, and the overall flow resistance is much lower than that of a series-connected unidirectional straight-through channel, requiring a lower pump head, reducing additional vibration from the pump, and improving the operational stability of the air-float electric spindle. Furthermore, the inlet and outlet ports 14 are concentrated at the tail end of the casing 1, allowing external pipelines to be connected on the same side, significantly simplifying the external pipeline layout and reducing wiring difficulty.

[0045] Example 2 The difference between this embodiment and Embodiment 1 lies in the specific implementation of the reflux turning structure 15. In this embodiment, the reflux turning structure 15 is implemented by machining a U-shaped flow channel inside the front cover of the housing 1. That is, an arc-shaped channel is machined inside the front cover of the housing 1, connecting the corresponding inlet pipe 101 and outlet pipe 102 through the arc-shaped channel inside the front cover, allowing the cooling water to return within the housing 1. The advantage of this method is that it does not require additional external pipes, resulting in a more compact structure.

[0046] Example 3 The difference between this embodiment and Embodiment 1 lies in the implementation method of the reflux turning structure 15. In this embodiment, an external U-shaped elbow fitting is used as the reflux turning structure 15, and the corresponding inlet pipe 101 and outlet pipe 102 are connected at the front end of the housing 1 through the U-shaped elbow. The advantage of this method is that it is simple to process and easy to maintain and replace.

[0047] Example 4 The difference between this embodiment and Embodiment 1 lies in the number of cooling pipe groups 10. The number of cooling pipe groups 10 can be adjusted according to the size of the housing 1 and the heat dissipation requirements, for example, it can be set to four, eight, or more groups, not limited to six groups. The number of inlet pipes 101 and outlet pipes 102 in each group of cooling pipes 10 can also be adjusted as needed. For example, each group may include two inlet pipes 101 and one outlet pipe 102, or one inlet pipe 101 and two outlet pipes 102, or multiple inlet pipes 101 and multiple outlet pipes 102, not limited to one inlet and one outlet.

[0048] Example 5 The difference between this embodiment and Embodiment 1 lies in the arrangement of the cooling pipes 10 on the cross-section of the shell 1. The cooling pipes 10 can be arranged at any position on the cross-section of the shell 1, as long as the inlet and outlet water are grouped together; they are not limited to the four corners or the left and right sides. For example, the cooling pipes 10 can be arranged on the upper and lower sides of the cross-section of the shell 1, or evenly distributed along the circumference, or adaptively adjusted according to the specific layout of the internal components of the shell 1. However, the arrangement of the cooling pipes 10 must be symmetrical along the central axis of the shell 1.

[0049] Example 6 The difference between this embodiment and Embodiment 1 lies in the location of the water collection tanks. The inlet water collection tank 11 and the drain water collection tank 13 can be located at positions other than the tail end of the housing 1, such as the front end or the center of the housing 1, as long as the centralized distribution and collection of coolant can be achieved. Preferably, the inlet water collection tank 11 and the drain water collection tank 13 are located at the same end of the housing 1 to simplify external piping connections. Alternatively, only the inlet water collection tank 11 or only the drain water collection tank 13 may be provided.

[0050] Example 7 The difference between this embodiment and Embodiment 1 lies in the flow direction of the coolant. With the inlet water collection tank 11 and the outlet water collection tank 13 simultaneously positioned at the front end of the housing 1, the coolant can first cool the direction from the motor 3 to the cutter head 4 (i.e., flow from the tail end to the front end and then back to the tail end), or it can first cool the cutter head 4 and the air bearing system, and then cool the direction from the motor 3 (i.e., flow from the front end to the tail end and then back to the front end). The specific flow direction can be selected according to actual heat dissipation requirements.

[0051] In summary, this invention, by incorporating parallel, axially extending, reversible cooling pipes 10 within the wall thickness of the housing 1, and arranging the inlet pipe 101 and outlet pipe 102 in parallel and opposite directions along the axial direction, allows the coolant to be diverted from the tail end of the housing 1 into all the inlet pipes 101, and then reversing at the front end before flowing back and converging out through the outlet pipe 102. This achieves sufficient cooling of the housing 1 and its internal heat-generating components, significantly reduces the temperature gradient within the housing 1, and makes the overall temperature distribution more uniform. Simultaneously, the parallel flow channel design shortens the flow path length, reduces overall flow resistance, lowers the pump head requirements, and reduces additional vibration. Furthermore, the centralized placement of the inlet and outlet at the same end of the housing 1 greatly simplifies the external piping layout and improves the operating accuracy and stability of the air-float electric spindle.

[0052] The embodiments described in this specific implementation are preferred embodiments of this application and are not intended to limit the scope of protection of this application. Identical components are represented by the same reference numerals. Therefore, all equivalent changes made to the structure, shape, and principle of this application should be included within the scope of protection of this application.

Claims

1. A housing cooling structure for an air-bearing electric spindle, comprising a housing, wherein a motor and an air-bearing system are disposed within the housing, the housing having an axially extending first end and a second end, the first end being the cutter head side and the second end being the motor side; characterized in that, The housing is provided with several sets of cooling pipes, each set of cooling pipes including at least one liquid inlet pipe and at least one liquid outlet pipe, both of which extend along the axial direction of the housing. The housing is provided with an inlet water collection tank and a drain water collection tank. The inlet water collection tank is connected to one end of each liquid inlet pipe and is used to centrally distribute the coolant to each liquid inlet pipe. The drain water collection tank is connected to one end of each liquid outlet pipe and is used to centrally collect the return coolant.

2. The housing cooling structure of the air-floating electric spindle according to claim 1, characterized in that, Both the inlet water collection tank and the outlet water collection tank are located at the second end of the shell, and the inlet water collection tank and the outlet water collection tank are isolated from each other.

3. The housing cooling structure of the air-floating electric spindle according to claim 2, characterized in that, The water inlet collection tank is provided with a water inlet, and the water outlet collection tank is provided with a water outlet. Both the water inlet and the water outlet are located at the second end of the shell.

4. The housing cooling structure of the air-floating electric spindle according to claim 1, characterized in that, The housing is also provided with a reflux turning structure, which is used to connect each inlet pipe to the corresponding outlet pipe at the other end of the housing, so that the coolant flows back from the inlet pipe through the reflux turning structure into the outlet pipe.

5. The housing cooling structure of the air-floating electric spindle according to claim 4, characterized in that, The reflux turning structure is located at the first end of the housing, and the reflux turning structure is a U-shaped reflux turning structure.

6. The housing cooling structure of the air-floating electric spindle according to claim 1, characterized in that, The number of cooling pipes is four or more, and the cooling pipes in each group are distributed on the cross-section of the shell as follows: at least two groups are located in the corner region of the cross-section of the shell, and at least two groups are located in the side region of the cross-section of the shell.

7. The housing cooling structure of the air-floating electric spindle according to claim 6, characterized in that, In each group of cooling pipes, the inlet pipe and the outlet pipe are arranged adjacent to each other on the cross-section of the shell; both the inlet pipe and the outlet pipe are located inside the wall of the shell.

8. The housing cooling structure of the air-floating electric spindle according to claim 1, characterized in that, It also includes a flow regulating device and / or a temperature detection device, wherein the flow regulating device is disposed on the coolant inflow path and the temperature detection device is disposed inside or on the housing, for adjusting the coolant flow rate according to the real-time temperature feedback signal inside the housing.

9. A method for cooling the housing of an air-bearing electric spindle, employing the housing cooling structure for an air-bearing electric spindle as described in any one of claims 1-8, characterized in that, Includes the following steps: a. Coolant enters the water inlet collection tank provided on the housing; b. After the coolant is collected in the water inlet tank, it is distributed in parallel into several inlet pipes and flows from one end of the housing to the other along the axial direction of the housing. During the flow, the motor and air bearing system inside the housing are cooled. c. After the coolant flows to the other end of the housing, it is turned back by the reflux turning structure provided on the housing and enters several outlet pipes; d. The coolant flows back from one end to the other along the outlet pipe, continuing to cool the shell during the backflow process; e. After the coolant flows back to the second end of the housing, it collects in the drain collection tank and is discharged from the housing.

10. The method for cooling the housing of an air-floating electric spindle according to claim 9, characterized in that: The coolant flows in parallel and in opposite directions in the inlet and outlet pipes.

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