Spindle cooling structure and machine tool

Abstract

The application discloses a main shaft cooling structure and a machine tool, and belongs to the technical field of main shafts. The main shaft cooling structure comprises a machine body, a front bearing seat and a rear bearing seat arranged in the machine body, bearings installed in the front bearing seat and the rear bearing seat, and a motor iron core and a motor coil arranged in the shell. The machine body is internally provided with cooling water channels. The cooling water channels comprise a plurality of independent cooling chambers. The plurality of cooling chambers are respectively arranged at positions corresponding to the bearings, the motor iron core and the motor coil of the main shaft. The cooling chambers are sequentially connected in series through pipeline holes, thereby forming a continuous circulating cooling path. The cooling liquid can sequentially flow through the cooling chambers corresponding to the front bearing, the front motor coil, the rear motor coil, the rear bearing and the motor iron core. The application incorporates the core heat source, i.e. the motor coil, into a direct liquid cooling circulating system, greatly expands the effective heat exchange area, and enables each heating part of the main shaft to be directly and fully cooled, thereby improving the overall heat dissipation efficiency.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of main shaft, in particular to the main shaft cooling structure and machine tool. BACKGROUND

[0002] As the core functional component of modern numerical control machine tool, the motorized spindle integrates the spindle and motor, has the advantages of compact structure, high power density, fast dynamic response, etc., and its performance directly determines the machining precision, efficiency and reliability of the machine tool. In the process of high-speed and high-load machining, a large amount of heat will be generated inside the motorized spindle, mainly from the electromagnetic loss of the motor core and coil, and the frictional heat of the front and rear support bearings. If the heat cannot be dissipated in time and effectively, the overall temperature of the spindle will rise, resulting in thermal deformation, which is manifested as axial thermal elongation and radial thermal drift.

[0003] In the prior art, the common motorized spindle cooling scheme mainly focuses on setting cooling water channels at the bearing seat and motor core parts. These schemes usually open simple annular water grooves or channels in the machine body or bearing seat, so that the cooling liquid flows through these areas to take away the heat. However, such traditional design has obvious limitations: first, the cooling range is not complete, especially for the motor stator coil which generates a lot of heat, there is a lack of direct and effective cooling measures, the heat generated by the coil can only be indirectly dissipated through heat conduction, which is low in efficiency, resulting in the coil area becoming a high-temperature hot spot. Secondly, the cooling flow channel design is often rough, there may be cross-flow or short circuit between different cooling areas, the cooling liquid is not evenly distributed, and it is impossible to realize differentiated and on-demand cooling for different heat sources. Finally, the cooling path lacks systematic planning, and the cooling sequence cannot be optimized according to the thermal characteristics (heat generation, heat capacity, and influence on precision) of each heat source.

[0004] The above defects collectively result in poor thermal performance of the motorized spindle: the bearing accelerates the failure of the lubricating grease due to excessive working temperature, the wear is aggravated, and the service life is shortened; the overall thermal equilibrium temperature of the motorized spindle is high, the thermal deformation is large and unstable, and in precision machining, it is easy to cause quality defects such as "machining surface unevenness" and "tool mark", which seriously restricts the machining precision limit of high-end machine tools. Therefore, developing a new structure that can efficiently, uniformly and controllably cool all key heat sources of the motorized spindle has become a technical problem to be solved in the field. SUMMARY

[0005] The technical problem to be solved by the present application is to overcome the shortcomings of the prior art and provide a motorized spindle cooling structure, aiming to solve the problem of heat damage caused by poor cooling of the motorized spindle and various machining problems.

[0006] In order to achieve the above-mentioned purposes, the main shaft cooling structure according to the first aspect of the present application comprises a machine body, a front bearing seat and a rear bearing seat arranged in the machine body, two bearings arranged in the front bearing seat and the rear bearing seat, and a motor core and a motor coil arranged in the machine body, wherein the machine body is internally provided with a cooling water channel, the cooling water channel is provided with a cooling liquid inlet and an outlet, and is used for circulating cooling of at least part of the heat generating components of the main shaft, the cooling water channel comprises a plurality of independent cooling chambers, and the plurality of cooling chambers are respectively arranged at the bearings, the motor core and the motor coil of the main shaft.

[0007] The cooling chambers are sequentially and continuously communicated through pipeline holes, so that the cooling liquid can sequentially flow through the cooling chambers corresponding to the front bearing, the front motor coil, the rear motor coil, the rear bearing and the motor core.

[0008] The plurality of cooling chambers at least comprise a front bearing cooling chamber, a rear bearing cooling chamber, a motor core position cooling chamber, a front motor coil cooling chamber and a rear motor coil cooling chamber.

[0009] The front bearing cooling chamber is formed by the front bearing seat and a cooling jacket.

[0010] The front motor coil cooling chamber and the rear motor coil cooling chamber are respectively formed by the cooling jacket and the machine body.

[0011] The rear bearing cooling chamber is formed by the rear bearing seat outer sleeve and the rear bearing seat.

[0012] The motor core position cooling chamber is formed by the inner wall of the machine body and the cooling jacket.

[0013] Optionally, adjacent cooling chambers are isolated from each other by O-rings.

[0014] Optionally, in the circulating cooling path, the flow sequence of the cooling liquid is from the front bearing cooling chamber, sequentially through the front motor coil cooling chamber, the rear motor coil cooling chamber, the rear bearing cooling chamber, and finally to the motor core position cooling chamber.

[0015] Optionally, the cooling jacket is a cylindrical structure sleeved outside the motor core and the coil, and the cooling jacket, the machine body and the front bearing seat jointly define the front motor coil cooling chamber.

[0016] Optionally, the rear bearing seat outer sleeve and the rear bearing seat are connected as an integral structure by embedding or welding.

[0017] Optionally, the structure of the front motor coil cooling chamber and / or the rear motor coil cooling chamber is arranged such that the corresponding part of the cooling jacket is integrated with the front bearing seat or the machine body to jointly form the cooling chamber.

[0018] Optionally, the flow sequence of the cooling liquid in the circulation cooling path is any one of the following: first flowing through the motor iron core position cooling chamber, the motor front end coil cooling chamber, the motor rear end coil cooling chamber, the front bearing cooling chamber, and then the rear bearing cooling chamber.

[0019] Alternatively, first flowing through the front bearing cooling chamber, the motor front end coil cooling chamber, the motor iron core position cooling chamber, the motor rear end coil cooling chamber, and then the rear bearing cooling chamber.

[0020] Optionally, the cooling liquid inlet is arranged on the rear bearing seat cover, and the cooling liquid outlet is arranged on the rear bearing seat cover.

[0021] Optionally, the motor front end coil cooling chamber, the front bearing cooling chamber, the motor rear end coil cooling chamber, the motor front end coil cooling chamber, the rear bearing cooling chamber, and the motor rear end coil cooling chamber are all provided with a communicating pipe hole.

[0022] The second aspect of the application provides a machine tool comprising the main shaft cooling structure.

[0023] The application has the following beneficial effects:

[0024] 1. The main shaft cooling structure of the application, by arranging a plurality of independent cooling chambers corresponding to the front bearing, the rear bearing, the motor iron core, the motor front end coil and the rear end coil, the core heat source of the motor coil is included in the direct liquid cooling circulation system. The effective heat exchange area is greatly expanded, and the bottleneck problem of insufficient cooling of the coil area in the traditional scheme is fundamentally solved, so that each heating part of the main shaft can be directly and fully cooled, and the overall heat dissipation efficiency is improved.

[0025] 2. The main shaft cooling structure of the application, O-rings are used to seal and isolate adjacent cooling chambers, which effectively prevents unintended flow of the cooling liquid between the chambers and ensures that the preset cooling liquid flow passes through the target area. Each cooling chamber becomes a controllable independent heat exchange unit, thereby ensuring the stability and uniformity of the cooling effect and avoiding local overheating caused by uneven flow distribution.

[0026] 3. The main shaft cooling structure of the application adopts a series path design and implements the flow sequence of “front bearing→motor coil→rear bearing→motor iron core”, which embodies a strategic heat management logic. The front bearing, which is most sensitive to the precision of the front end of the main shaft, is preferentially cooled to quickly and stably control its working temperature and maximize the inhibition of the thermal elongation of the main shaft. Then the coil with high heat is cooled to block the heat transfer to adjacent components. This sequential cooling can reasonably utilize the temperature rise gradient of the cooling liquid and achieve optimal allocation of cooling efficiency, thereby controlling the overall thermal deformation of the main shaft at a very low level.

[0027] 4、The spindle cooling structure of the present application provides flexible design space for spindles of different power, different speed, and different application scenarios (such as carving and milling, grinding machine, lathe) through the disclosed cooling chamber configuration mode (such as the integrated design of the cooling water jacket and the bearing seat) and various optional schemes of the cooling liquid flow sequence. Designers can adjust the cooling strategy according to the main heat source distribution and the precision control focus, so that the technology has wide versatility and strong vitality. BRIEF DESCRIPTION OF DRAWINGS

[0028] Figure 1 Fig. 1 is a schematic view of the spindle cooling structure and the cooling water channel structure of the machine tool of the present application;

[0029] Figure 2 Fig. 2 is a schematic view of the top structure of the spindle cooling structure and the machine tool of the present application;

[0030] Figure 3 Fig. 3 is a schematic view of the cooling liquid circulation of the spindle cooling structure and the machine tool of the present application;

[0031] Figure 4 Fig. 4 is a schematic view of the total distribution structure of the cooling chamber of the spindle cooling structure and the machine tool of the present application;

[0032] Figure 5 Fig. 5 is a schematic view of the connection structure of the motor front-end coil cooling chamber and the front bearing cooling chamber of the spindle cooling structure and the machine tool of the present application;

[0033] Figure 6 Fig. 6 is a schematic view of the connection structure of the motor rear-end coil cooling chamber and the motor front-end coil cooling chamber of the spindle cooling structure and the machine tool of the present application;

[0034] Figure 7 Fig. 7 is a schematic view of the connection structure of the rear bearing cooling chamber and the motor rear-end coil cooling chamber of the spindle cooling structure and the machine tool of the present application;

[0035] Figure 8 Fig. 8 is a schematic view of the connection structure of the rear bearing cooling chamber and the motor core position cooling chamber of the spindle cooling structure and the machine tool of the present application.

[0036] KEY

[0037] 1, rear bearing seat cover; 2, rear bearing seat; 3, machine body; 4, motor; 5, cooling water jacket; 6, front bearing seat; 7, O-ring; 8, bearing; 9, rear bearing cooling chamber; 10, motor rear-end coil cooling chamber; 11, motor core position cooling chamber; 12, motor front-end coil cooling chamber; 13, front bearing cooling chamber.

[0038] The implementation, functional features and advantages of the present application will be further described with reference to the embodiments and the accompanying drawings. DETAILED DESCRIPTION

[0039] It should be understood that the specific embodiments described herein are merely exemplary and do not limit the present application.

[0040] In the description of the present application, it should be noted that unless otherwise explicitly specified and limited, the terms "mounting", "connection", "connecting" should be understood in a broad sense, for example, it can be fixed connection, or detachable connection, or integrally connected; it can be mechanical connection, it can be direct connection, or indirect connection through intermediate medium, it can be internal communication of two elements or interaction relationship between two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0041] Embodiment 1

[0042] With reference to Figures 1-8 , an embodiment of the main shaft cooling structure provided by an embodiment of the present application comprises a body 3, a front bearing seat 6 and a rear bearing seat 2 arranged in the body 3, two bearings 8 mounted in the front bearing seat 6 and the rear bearing seat 2, and a motor core and a motor coil arranged in the shell. The body 3 is internally provided with a cooling water channel, the cooling water channel is provided with a cooling liquid inlet and an outlet, and is used for circulating cooling at least part of the heat generating components of the main shaft. The cooling water channel comprises a plurality of independent cooling chambers, and the plurality of cooling chambers correspond to the bearings 8, the motor core and the motor coil arranged at the main shaft, respectively.

[0043] The cooling chambers are sequentially connected in series through pipe holes, and form a continuous circulating cooling path, so that the cooling liquid can sequentially flow through the cooling chambers corresponding to the front bearing, the motor front coil, the motor rear coil, the rear bearing and the motor core. And the bearing 8 comprises a front bearing and a rear bearing.

[0044] It should be noted that, as Figure 1 , Figure 3 shown, the main shaft cooling structure of the present application mainly comprises a body 3, a front bearing seat 6, a rear bearing seat 2, a cooling water jacket 5, a rear bearing seat outer sleeve 1 and necessary sealing elements such as O-rings 7. The motor core and coil (not marked in the figure) are mounted in the body 3. The cooling liquid (such as water or oil-based cooling liquid) is pumped from the external cooling system, flows out after flowing through the continuous cooling water channel formed in the internal structure, and carries away the heat.

[0045] The cooling liquid enters the system from the cooling liquid inlet arranged on the rear bearing seat outer sleeve 1, and sequentially flows through the following five cooling chambers which are isolated from each other and connected in series through pipe holes:

[0046] The front bearing cooling chamber 13 preferentially cools the front bearing.

[0047] The motor front end coil cooling chamber 12 cools the motor coil part close to the front bearing side.

[0048] The motor rear end coil cooling chamber 10 cools the motor coil part close to the rear bearing side.

[0049] The rear bearing cooling chamber 9 cools the rear bearing.

[0050] The motor core position cooling chamber 11 cools the motor core lastly.

[0051] After the cooling of the motor core is completed, the cooling liquid is returned to the cooling liquid outlet on the rear bearing seat cover 1 through the pipeline in the machine body 3, completing a complete cycle. This path ensures that the cooling liquid can sequentially and sufficiently exchange heat with each major heat source.

[0052] The cooling water channel is formed by a plurality of independent cooling chambers in series, forming a continuous cooling network covering all key heat generating components. The beneficial effect of this structure is that it divides the overall cooling task into targeted cooling of local heat sources, avoiding the cooling dead angle and uneven flow distribution problems that may occur in traditional single water cavity. The series design ensures that the cooling liquid under a given flow rate can flow through all the predetermined positions in sequence, realizing the effective utilization of cooling resources and the systematization of thermal management, and overall improving the uniformity and reliability of cooling. The motor front end coil cooling chamber 12 and the front bearing cooling chamber 13, the motor rear end coil cooling chamber 10 and the motor front end coil cooling chamber 12, the rear bearing cooling chamber 9 and the motor rear end coil cooling chamber 10, and the rear bearing cooling chamber 9 and the motor core position cooling chamber 11 all have communicating pipeline holes.

[0053] In some embodiments, the plurality of cooling chambers at least includes a front bearing cooling chamber 13, a rear bearing cooling chamber 9, a motor core position cooling chamber 11, a motor front end coil cooling chamber 12 and a motor rear end coil cooling chamber 10. The front bearing cooling chamber 13 is formed by the front bearing seat 6 and a cooling jacket 5;

[0054] The motor front end coil cooling chamber 12 and the motor rear end coil cooling chamber 10 are formed by the cooling jacket 5 and the machine body 3, respectively;

[0055] The rear bearing cooling chamber 9 is formed by the rear bearing seat cover 1 and the rear bearing seat 2;

[0056] The motor core position cooling chamber 11 is formed by the inner wall of the machine body 3 and the cooling jacket 5.

[0057] It should be noted that the plurality of cooling chambers specifically includes a front bearing cooling chamber 13, a rear bearing cooling chamber 9, a motor core position cooling chamber 11, a motor front end coil cooling chamber 12 and a motor rear end coil cooling chamber 10. Formed by the following ways:

[0058] The front bearing cooling chamber 13 is formed by the front bearing seat 6 and the front end portion of the cooling jacket 5 sleeved outside the motor. This surrounding structure directly forms a cooling cavity on the periphery of the bearing seat, so that the cooling liquid flows closely around the outer ring of the bearing 8.

[0059] The motor front end coil cooling chamber 12 and the motor rear end coil cooling chamber 10 are mainly composed of the annular space between the outer wall of the cooling jacket 5 and the inner wall of the body 3. The cooling jacket 5 acts as a partition to separate the coil area from other parts of the body, thereby forming a cooling cavity around the coil.

[0060] The rear bearing cooling chamber 9 is formed by the annular gap between the rear bearing seat outer sleeve 1 and the rear bearing seat 2 installed inside.

[0061] The motor core position cooling chamber 11 is formed by the inner wall of the body 3 and the outer wall of the cooling jacket 5 in the area corresponding to the length of the motor core. The cooling jacket 5 also serves as a key component to form a cooling flow channel here.

[0062] The existing mechanical structure (such as the bearing seat, the body 3) is fully utilized and a special component (the cooling jacket) is introduced to achieve the most direct wrapping cooling of each heat generating part with minimal space modification, greatly increasing the effective heat exchange area between the cooling liquid and the heat source.

[0063] In some embodiments, adjacent cooling chambers are isolated from each other by O-rings 7.

[0064] It should be noted that O-rings 7 are provided at the junction between adjacent cooling chambers for sealing and isolation, ensuring the independence between each cooling chamber and preventing cooling liquid short circuiting or flow.

[0065] In some embodiments, in the circulating cooling path, the flow sequence of the cooling liquid is from the front bearing cooling chamber 13, through the motor front end coil cooling chamber 12, the motor rear end coil cooling chamber 10, the rear bearing cooling chamber 9 in turn, and finally to the motor core position cooling chamber 11.

[0066] It should be noted that in the circulation path, the cooling liquid is designed to flow in the order of front bearing → motor front-end coil → motor rear-end coil → rear bearing → motor core. Strategic cooling priority is achieved. First, the front bearing, which has the heaviest load and the greatest impact on the front-end precision of the main shaft, is cooled to quickly stabilize its working temperature and minimize the thermal elongation of the main shaft. Then, the motor coil, which generates intense heat, is cooled to intercept the heat transfer to the bearing 8 and the core. After the temperature of the cooling liquid has risen, the rear bearing, which has relatively small heat generation and is floating, is cooled, which has limited impact on its performance. Finally, the motor core, which has a large heat capacity, is cooled, and the cooling liquid that has flowed through all the heat sources can still effectively remove the accumulated heat. The utilization of the cooling liquid temperature rise curve is optimized, and the cooling efficiency is maximized.

[0067] In some embodiments, the cooling jacket 5 is a cylindrical structure that is sleeved outside the motor core and coil, and cooperates with the machine body 3 and the front bearing seat 6 to define the motor front-end coil cooling chamber 12.

[0068] It should be noted that the cooling jacket 5 is a cylindrical structure that is sleeved outside the motor stator (including the core and the coil). As a core functional component, it integrally participates in forming the boundaries of the motor front-end coil cooling chamber 12, the motor core cooling chamber 11, and the motor rear-end coil cooling chamber 10 (or part). This design simplifies the processing of the internal flow channel of the machine body 3, converts the complex cooling cavity into a space formed by assembling a prefabricated part with the machine body 3, improves the processability and reliability of the structure, and ensures the integrity of the cooling of the coil and core area.

[0069] In some embodiments, the rear bearing seat outer sleeve 1 and the rear bearing seat 2 are connected as an integrated structure by embedding or welding.

[0070] It should be noted that the rear bearing seat outer sleeve 1 and the rear bearing seat 2 can be connected as an integrated structure by embedding or welding. Integrating the two parts eliminates the risk of leakage that may exist at the joint surface of the two parts, enhances the structural rigidity and sealing reliability of the rear bearing cooling chamber 9. The integrated design also reduces the assembly steps, improves the integrity and stability of the components.

[0071] In some embodiments, the structure of the motor front-end coil cooling chamber 12 and / or the motor rear-end coil cooling chamber 10 is arranged such that the corresponding part of the cooling jacket 5 is integrated with the front bearing seat 6 or the machine body 3 to jointly form the cooling chamber.

[0072] As another implementation, the corresponding part (e.g. end) of the cooling jacket 5 and the front bearing seat 6 or the body 3 are integrated together (e.g. designed as an integral part or connected in a non-detachable manner) to form the cooling chamber. This further reduces the number of parts and assembly interfaces, and in some designs, can simplify the sealing requirements or optimize the shape of the cooling flow passage in certain areas, providing flexibility for the design of the main shaft of different models and space limitations.

[0073] In some embodiments, the flow sequence of the cooling liquid in the circulation cooling path is any one of the following: first through the motor core position cooling chamber 11, the motor front end coil cooling chamber 12, the motor rear end coil cooling chamber 10, the front bearing cooling chamber 13, and then to the rear bearing cooling chamber 9.

[0074] Alternatively, first through the front bearing cooling chamber 13, the motor front end coil cooling chamber 12, the motor core position cooling chamber 11, the motor rear end coil cooling chamber 10, and then to the rear bearing cooling chamber 9.

[0075] It should be noted that the flow sequence of the cooling liquid in the circulation cooling path can be adjusted according to different heat management strategies. For example, it can be set to: first through the motor core position cooling chamber 11, the motor front end coil cooling chamber 12, the motor rear end coil cooling chamber 10, the front bearing cooling chamber 13, and then to the rear bearing cooling chamber 9; or, first through the front bearing cooling chamber 13, the motor front end coil cooling chamber 12, the motor core position cooling chamber 11, the motor rear end coil cooling chamber 10, and then to the rear bearing cooling chamber 9. The adjustability of the flow sequence has the beneficial effect that it enables the cooling structure to adapt to different working conditions and application requirements. For example, when the motor load is extremely large and becomes the main heat source, the sequence of preferentially cooling the motor and the coil can be used; when it is necessary to extremely control the precision of the front end of the main shaft, the scheme of preferentially cooling the front bearing can be strengthened.

[0076] In some embodiments, the cooling liquid inlet is provided on the rear bearing seat outer sleeve 1, and the cooling liquid outlet is provided on the rear bearing seat outer sleeve 1.

[0077] It should be noted that the cooling liquid inlet and outlet are both centrally provided on the rear bearing seat outer sleeve 1. The beneficial effect of this arrangement is that it integrates the input and output interfaces of the cooling liquid on the non-driving end (rear end) of the main shaft, making the connection of the external cooling pipeline more centralized and convenient, avoiding the need to open holes in multiple places on the main shaft housing, and being conducive to the sealing design and overall neat appearance of the main shaft.

[0078] In summary, the cooling circulation path in the present application is not limited to the above preferred sequence. Based on the same structure of multiple independent cooling chambers in series, different cooling sequences can be easily realized by changing the layout of the pipe holes connecting the cooling chambers. For example:

[0079] Scheme A: The cooling liquid flows through the motor core position cooling chamber 11→ the motor front end coil cooling chamber 12→ the motor rear end coil cooling chamber 10→ the front bearing cooling chamber 13→ the rear bearing cooling chamber 9 in turn. This scheme prioritizes the overall heating of the motor 4, and is suitable for the continuous high load working condition of the motor 4.

[0080] Scheme B: The cooling liquid flows through the front bearing cooling chamber 13→ the motor front end coil cooling chamber 12→ the motor core position cooling chamber 11→ the motor rear end coil cooling chamber 10→ the rear bearing cooling chamber 9 in turn. This scheme cools the front bearing first, and then cools the adjacent part of the motor 4, which helps to control the temperature rise gradient of the front end of the main shaft.

[0081] The above examples do not deviate from the core concept of using series independent cooling chambers for systematic cooling, and can obtain corresponding cooling benefits according to the actual heat distribution characteristics.

[0082] Embodiment 2

[0083] The present embodiment provides a machine tool including a spindle unit, and the spindle unit adopts the aforementioned spindle cooling structure. The machine tool can be a machining center, a numerical control milling machine, a turning and milling combined machine tool, a grinding machine or any type of machine tool that requires high precision and high speed spindle. The spindle cooling structure as the core thermal management component of the machine tool spindle is integrated and installed in the spindle box or the corresponding support structure of the machine tool.

[0084] Due to the adoption of the aforementioned efficient and precise spindle cooling structure, the spindle of the machine tool is effectively inhibited in temperature rise and significantly reduced in thermal deformation under high speed, heavy load and long time running conditions. This directly translates into higher machining precision stability, better surface machining quality and longer service life of the spindle of the machine tool. At the same time, the good heat dissipation capacity allows the spindle to work continuously at higher power and speed, improving the overall machining efficiency and performance potential of the machine tool.

[0085] In specific application, firstly, the liquid supply pipeline of the external cooling system is connected with the cooling liquid inlet arranged on the rear bearing seat outer sleeve 1 of the non-driving end of the main shaft, and the liquid return pipeline is connected with the cooling liquid outlet on the outer sleeve, thus completing the physical connection of the cooling loop; the external cooling system is started, and the cooling liquid is pumped in through the inlet, firstly entering the starting end of the series circulation cooling path, i.e. the front bearing cooling chamber 13 formed by the front bearing seat 6 and the cooling jacket 5, and circulating in the chamber to directly take away the heat generated by the front bearing during operation, thus realizing the preferential cooling of the key support part of the main shaft and being beneficial to controlling the thermal elongation of the front end of the main shaft; then, the cooling liquid flows into the motor front end coil cooling chamber 12 formed by the cooling jacket 5 and the inner wall of the machine body 3 through the pipeline hole in the machine body 3, and the motor coil section adjacent to the front bearing is cooled; then, the cooling liquid continues to flow through the motor rear end coil cooling chamber 10 of the same structure, thus completing the covering cooling of the overall heat generation of the motor coil; thereafter, the cooling liquid with the temperature increased enters the rear bearing cooling chamber 9 formed by the rear bearing seat outer sleeve 1 and the rear bearing seat 2, and the rear bearing with relatively small heat generation is fully cooled; finally, the cooling liquid flows into the motor iron core position cooling chamber 11 formed by the inner wall of the machine body 3 and the cooling jacket 5 in the axial area of the motor iron core, and the motor iron core with large heat capacity is cooled in the final stage; the cooling liquid completing the overall heat exchange finally returns to the outlet of the rear bearing seat outer sleeve 1 through the pipeline of the machine body 3, and is discharged to the external cooling system for cooling treatment, thus constituting a continuously running closed circulation.

[0086] The above only describes the preferred embodiments of the present application, and does not limit the patent scope of the present application, and any equivalent structure or equivalent flow transformation using the content of the specification and drawings, or direct or indirect application in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. A spindle cooling structure, comprising a body (3), a front bearing housing (6) and a rear bearing housing (2) disposed within the body (3), two bearings (8) installed within the front bearing housing (6) and the rear bearing housing (2), and a motor core and a motor coil disposed within the body (3), wherein the body (3) is provided with a cooling water channel, the cooling water channel having a coolant inlet and an outlet, for circulating cooling of at least a portion of the heat-generating components of the spindle, characterized in that: The cooling water channel includes multiple independent cooling chambers, which are respectively located at the front bearing of the main shaft, the front coil of the motor, the rear coil of the motor, the rear bearing, and the motor core. The cooling chambers are connected in series through pipe holes to form a continuous circulating cooling path, so that the coolant can flow sequentially through the cooling chambers corresponding to the front bearing, the front coil of the motor, the rear coil of the motor, the rear bearing, and the motor core. The plurality of cooling chambers include at least a front bearing cooling chamber (13), a rear bearing cooling chamber (9), a motor core cooling chamber (11), a front coil cooling chamber (12) and a rear coil cooling chamber (10). The front bearing cooling chamber (13) is formed by the front bearing housing (6) and a cooling water jacket (5); The front coil cooling chamber (12) and the rear coil cooling chamber (10) of the motor are respectively enclosed by the cooling water jacket (5) and the body (3); The rear bearing cooling chamber (9) is formed by the rear bearing housing outer sleeve (1) and the rear bearing housing (2); The motor core cooling chamber (11) is formed by the inner wall of the machine body (3) and the cooling water jacket (5); The coolant enters the cooling water channel through the coolant inlet and flows sequentially through the following five mutually isolated cooling chambers connected in series via pipe holes: The front bearing cooling chamber (13) is configured to prioritize cooling of the front bearing located in the critical support part of the spindle, in order to quickly stabilize the working temperature of the front bearing and control the thermal expansion of the spindle. The motor front coil cooling chamber (12) is configured to cool the motor coil portion near the front bearing side, and is used to cool the motor coil that generates intense heat, so as to intercept the transfer of heat from the front coil to the front bearing and the iron core. The motor rear coil cooling chamber (10) is configured to cool the motor coil portion near the rear bearing side, and is used to cool the motor coil that generates intense heat, so as to intercept the transfer of heat from the rear coil to the rear bearing and the iron core. The rear bearing cooling chamber (9) is configured to cool the rear bearing, which generates relatively little heat, after the coolant temperature has already increased. The motor core cooling chamber (11) is configured to cool the motor core with a large cooling heat capacity, and to use the coolant flowing through all heat sources to remove the heat accumulated in the motor core; After the cooling of the motor core is completed, the coolant flows back to the coolant outlet through the pipe hole in the machine body (3) to complete a complete cycle, so that the coolant can exchange heat with each of the main heat sources in sequence using the coolant temperature rise curve.

2. The spindle cooling structure according to claim 1, characterized in that, Adjacent cooling chambers are isolated from each other by O-rings (7).

3. The spindle cooling structure according to claim 1, characterized in that, The cooling water jacket (5) is a cylindrical structure sleeved on the outside of the motor core and coil. Together with the body (3) and the front bearing seat (6), it defines the front coil cooling chamber (12) of the motor.

4. The spindle cooling structure according to claim 1, characterized in that, The rear bearing housing outer sleeve (1) and the rear bearing housing (2) are connected as an integral structure by embedding or welding.

5. The spindle cooling structure according to claim 1, characterized in that, The coolant inlet is located on the rear bearing housing outer sleeve (1), and the coolant outlet is located on the rear bearing housing outer sleeve (1).

6. The spindle cooling structure according to claim 1, characterized in that, The front coil cooling chamber (12) of the motor and the front bearing cooling chamber (13), the rear coil cooling chamber (10) of the motor and the front coil cooling chamber (12), the rear bearing cooling chamber (9) and the rear coil cooling chamber (10), and the rear bearing cooling chamber (9) and the motor core cooling chamber (11) are all connected by pipe holes.

7. A machine tool, characterized in that, Includes the spindle cooling structure as described in any one of claims 1 to 6.

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