Motorized spindle rotor mounting structure, motorized spindle and machine tool

Abstract

The application discloses a motorized spindle rotor mounting structure, a motorized spindle and a machine tool, which comprises a shaft core, a rotor, a clamping sleeve, and a locking ring. The rotor is internally provided with a through mounting hole. The clamping sleeve is arranged on the outer peripheral wall of the shaft core and penetrates through the mounting hole, and the clamping sleeve can rotate synchronously with the shaft core. The two ends of the clamping sleeve extend out of the mounting hole. The locking ring is distributed at the two ends of the rotor and is connected with the rotor through fasteners. The clamping sleeve comprises a main body part and extension parts connected to the two ends of the main body part. The outer peripheral surface of the extension part is a first tapered surface. The locking ring is provided with an inner hole, the inner peripheral surface of the inner hole is a second tapered surface, the extension part enters the inner hole, and the first tapered surface and the second tapered surface are in mutual abutment. The clamping sleeve is additionally arranged, the locking ring connected with the rotor is connected, the disassembly and assembly between the rotor and the shaft core are realized, the mounting form of the traditional rotor adopting the heat expansion and cold contraction process is replaced, and the disassembly and assembly operation of the rotor is facilitated.

Description

Technical Field

[0001] This application relates to the technical field of electric spindles, and in particular to an electric spindle rotor mounting structure, an electric spindle, and a machine tool. Background Technology

[0002] An electric spindle is a new technology in the field of CNC machine tools that integrates the machine tool spindle and the spindle motor. The main structure of an electric spindle includes a spindle core and an AC asynchronous induction motor. The rotor in the motor is connected to the spindle core, thereby driving the spindle core to rotate at high speed. Patent announcement number CN105537629B discloses "an intelligent electric spindle," which includes a drive rotor and a drive stator. The drive stator is fixed inside an outer casing and connected to the central spindle core.

[0003] In existing technologies, the shaft and rotor are generally fixed using a thermal expansion and contraction method. That is, when connecting the rotor to the shaft, the rotor is first heated to expand its inner bore, then the shaft is inserted into the rotor's inner bore. After the rotor cools, the diameter of the rotor's inner bore shrinks, completing the fixed connection with the shaft. This installation method is relatively cumbersome, and the rotor is not easy to disassemble after installation. Utility Model Content

[0004] To facilitate the assembly and disassembly of the rotor and shaft, the primary objective of this application is to provide an electric spindle rotor mounting structure.

[0005] The electric spindle rotor mounting structure provided in this application adopts the following technical solution:

[0006] An electric spindle rotor mounting structure, comprising:

[0007] Shaft core;

[0008] The rotor has a through mounting hole inside it;

[0009] A sleeve, surrounding the outer peripheral wall of the shaft and passing through a mounting hole, the sleeve being able to rotate synchronously with the shaft, with both ends extending out of the mounting hole; and

[0010] Locking rings are distributed at both ends of the rotor, and the locking rings are connected to the rotor by fasteners;

[0011] The sleeve includes a main body and extensions connected to both ends of the main body. The outer peripheral surface of the extension is a first conical surface. The locking ring has an inner hole, and the inner peripheral surface of the inner hole is a second conical surface. The extension enters the inner hole and the first conical surface and the second conical surface abut against each other.

[0012] By adopting the above technical solution, a jacket is added to connect with the shaft core. The rotor is fitted onto the jacket, and the connection between the jacket and the rotor is achieved through a locking ring and fasteners. This connects the shaft core, jacket, rotor, and locking ring. Disassembly and assembly of the rotor only requires removing the locking ring to separate it from the shaft core, eliminating the need for thermal expansion and contraction processes, making operation convenient. Furthermore, the connection between the locking ring and the jacket is achieved through the abutment of a first conical surface and a second conical surface. This ensures a stronger connection as the locking ring moves towards the main body of the jacket. Additionally, the ability of the locking ring to slide relative to the jacket allows for connections of rotors of different lengths.

[0013] Preferably, the jacket is an elastic jacket.

[0014] By adopting the above technical solution, the elastic sleeve will undergo slight deformation under the sliding compression of the locking ring to increase the compressive force between the sleeve and the shaft and rotor, thereby improving the connection strength between the rotor and the shaft. The elastic sleeve can be made of spring steel, which has stable elastic properties at high temperatures. The operating temperature of the electric spindle generally does not exceed 80°C, which can better maintain the stability of the sleeve's performance during operation.

[0015] Preferably, the shaft core is a stepped shaft with a shoulder, and one end of the sleeve abuts against the shoulder.

[0016] By adopting the above technical solution, one end of the sleeve abuts against the shoulder of the shaft to achieve axial positioning on one side of the shaft core, thereby improving the rapid positioning operation of the sleeve on the shaft core.

[0017] To facilitate the assembly and disassembly of the rotor and shaft, a second objective of this application is to provide an electric spindle.

[0018] The electric spindle provided in this application adopts the following technical solution:

[0019] An electric spindle includes:

[0020] A spindle seat having mounting cavities open at both ends;

[0021] The stator is disposed within the inner wall of the mounting cavity; and

[0022] The electric spindle rotor mounting structure wherein the rotor passes through the stator.

[0023] By adopting the above technical solution, the rotor is sleeved on the jacket, and the connection between the jacket and the rotor is achieved by the locking ring and fasteners, thereby realizing the connection of the shaft, jacket, rotor and locking ring. The rotor can be disassembled and assembled simply by removing the locking ring to separate it from the shaft, without the need to use thermal expansion and contraction process for disassembly and assembly, making the operation convenient.

[0024] Preferably, it further includes a front bearing assembly, the front bearing assembly comprising:

[0025] Front bearing housing, which is connected to the main shaft housing;

[0026] Several front bearings are mounted on the shaft core and placed inside the front bearing housing;

[0027] The first front retaining ring is mounted on the shaft core, and one end face of the first front retaining ring is adjacent to one side of several front bearings;

[0028] A first rear retaining ring is mounted on the shaft core, and one end face of the first rear retaining ring abuts against the other side of a plurality of front bearings; and

[0029] The first locking nut is threaded onto the shaft and abuts against the first rear retaining ring;

[0030] The shaft core includes a stop extending radially from its end, the stop abutting against the first front retaining ring.

[0031] By adopting the above technical solution, when the shaft core rotates at high speed, it will be subjected to axial force due to the machining of the workpiece. The outward-facing stop at the end of the shaft core increases the axial force-bearing area. Therefore, when the stop comes into contact with the first front retaining ring, it can transmit the axial load force as evenly as possible, thereby improving the service life of each component. Secondly, since the design of the stop replaces the locking nut limit on the front bearing side, and the locking nut and shaft core are connected by threads, the threads between the locking nut and shaft core have a certain axial fit clearance. Under axial force, after long-term operation, the locking nut and shaft core will undergo relative axial movement. During the movement, the threads are squeezed and worn. This replacement design of the stop further improves the service life of each component.

[0032] Preferably, it further includes a rear bearing assembly, the rear bearing assembly comprising:

[0033] Rear bearing housing, which is connected to the main shaft housing;

[0034] Several rear bearings are mounted on the shaft core and placed inside the rear bearing housing;

[0035] The second front retaining ring is mounted on the shaft core and its two end faces respectively abut against one side of a plurality of front bearings and the end face of the extension.

[0036] A second rear retaining ring is mounted on the shaft core, and one end face of the second rear retaining ring abuts against the other side of several front bearings; and

[0037] The second locking nut is threaded onto the shaft and abuts against the second rear retaining ring.

[0038] By adopting the above technical solution, the second front retaining ring limits one side of the jacket and the rear bearing, and the second locking nut, together with the second rear retaining ring, limits the other side of the rear bearing, thereby maintaining the axial positioning of several bearings on the shaft core.

[0039] Preferably, it further includes a front end cover connected to the front bearing housing, the front end cover including an inner ring extending toward one side of the shaft core, one side of the inner ring abutting against one side of a plurality of front bearings, and one end of the inner ring being connected to a first front retaining ring.

[0040] By adopting the above technical solution, the front cover can further limit the axial movement of the front bearing side. At the same time, the inner ring of the front cover is also connected to the first front retaining ring. Both can withstand the axial action generated by the workpiece processing, and better distribute the axial load evenly.

[0041] Preferably, the inner ring has a first hook portion, the first front retaining ring has a second hook portion, and the first hook portion and the second hook portion engage with each other.

[0042] By adopting the above technical solution, the engagement of the first hook and the second hook limits their radial movement and achieves better installation and positioning.

[0043] Preferred options also include:

[0044] The tie rod passes through the shaft and can rotate synchronously with the shaft.

[0045] A pull pawl, connected to one end of the pull rod and extending from within the shaft core; and

[0046] The guide sleeve connects to the stop.

[0047] The pull claw is located inside the guide sleeve and can move axially relative to the guide sleeve. The pull claw has a clamping hole, and the diameter of the clamping hole can be increased or decreased when the pull claw moves axially relative to the guide sleeve.

[0048] By adopting the above technical solution, when the workpiece is connected to the electric spindle, the workpiece is installed in the clamping hole of the pull claw. When the pull claw undergoes axial displacement through the connected pull rod, it is squeezed against the guide sleeve, thereby changing the size of the clamping hole to achieve the clamping operation of the workpiece.

[0049] To facilitate the assembly and disassembly of the rotor and shaft, a third objective of this application is to provide a machine tool.

[0050] The machine tool provided in this application adopts the following technical solution:

[0051] A machine tool including the electric spindle.

[0052] By adopting the above technical solution, the rotor is sleeved on the jacket, and the connection between the jacket and the rotor is achieved by the locking ring and fasteners, thereby realizing the connection of the shaft, jacket, rotor and locking ring. The rotor can be disassembled and assembled simply by removing the locking ring to separate it from the shaft, without the need to use thermal expansion and contraction process for disassembly and assembly, making the operation convenient.

[0053] In summary, this application includes at least one of the following beneficial technical effects:

[0054] 1. By adding a jacket and connecting it to the locking ring, the rotor and shaft can be disassembled and assembled, replacing the traditional rotor installation method that uses thermal expansion and contraction, which facilitates the disassembly and assembly of the rotor.

[0055] 2. By replacing the locking nut installed near the workpiece with a stop at the end of the shaft core, the axial load resistance is improved. At the same time, the service life of each component is improved because the locking nut that abuts against the first front retaining ring is replaced. Attached Figure Description

[0056] Figure 1 This is a schematic diagram of the electric spindle rotor mounting structure in Example 1;

[0057] Figure 2 for Figure 1 Enlarged view of part A;

[0058] Figure 3 This is a schematic diagram of the electric spindle in Example 2;

[0059] Figure 4 This is a schematic diagram showing the connection between the front cover and the first front retaining ring in Embodiment 2.

[0060] Explanation of reference numerals in the attached drawings: 1. Shaft core; 11. Shoulder; 12. Stop; 2. Rotor; 3. Jacket; 31. Main body; 32. Extension; 321. First conical surface; 4. Locking ring; 41. Second conical surface; 5. Fastener; 6. Tie rod; 7. Front bearing assembly; 71. Front bearing seat; 72. Front bearing; 73. First front retaining ring; 731. Second hook; 74. First rear retaining ring; 75. First locking nut; 8. Rear bearing assembly; 81. Rear bearing seat; 82. Rear bearing; 83. Second front retaining ring; 84. Second rear retaining ring; 85. Second locking nut; 9. Pull claw; 10. Main shaft seat; 20. Stator; 30. Front end cover; 301. Inner ring; 3011. First hook; 40. Guide sleeve. Detailed Implementation

[0061] The present application will be further described in detail below with reference to the accompanying drawings.

[0062] It should be noted that when an element is referred to as being "fixed to" another element, it can be directly attached to the other element or there may be an intervening element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or there may be an intervening element. The terms "vertical," "horizontal," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only possible implementation.

[0063] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein in the specification of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items. Example 1

[0064] Figure 1 and Figure 2 A schematic diagram of an electric spindle rotor mounting structure is shown, including a spindle core 1, a rotor 2, a sleeve 3, and a locking ring 4. The sleeve 3 is mounted on the outer circumferential surface of the spindle core 1, and the two are connected by an transition fit, so that the rotation of the spindle core 1 can drive the rotation of the sleeve 3.

[0065] The sleeve 3 includes a cylindrical main body 31 and extensions 32 connected to both ends of the main body 31. A through mounting hole is formed in the middle of the rotor 2, and the sleeve 3 passes through the mounting hole, such that the main body 31 is placed within the mounting hole while the extensions 32 on both sides extend out of the mounting hole. In this embodiment, the rotor 2 and the sleeve 3 can be fitted with a clearance or a transition fit. When a transition fit is used, only an axial force needs to be applied to the rotor 2 to drive it into the sleeve 3.

[0066] The two extensions 32 of the sleeve 3 are symmetrically distributed, and their outer peripheral surfaces are configured as a first conical surface 321. The locking ring 4 has an inner hole, and the inner peripheral surface of the inner hole is configured as a second conical surface 41. Thus, when the extension 32 enters the inner hole of the locking ring 4 and when the first conical surface 321 and the second conical surface 41 abut against each other, the locking ring 4 can be fixedly connected to the extension 32. At the same time, when the locking ring 4 slides along the first conical surface 321 toward the main body 31, the compressive force between the first conical surface 321 and the second conical surface 41 gradually increases, thereby improving the connection strength between the locking ring 4 and the extension 32.

[0067] The locking ring 4 has multiple through holes circumferentially opened on its side. Fasteners 5 are inserted through the through holes, and one end of the fastener 5 is connected to the rotor 2, thereby realizing the connection between the locking ring 4 and the rotor 2. Furthermore, in this embodiment, the fastener 5 is a locking screw, and the locking screw is threadedly connected to the rotor 2. When the locking ring 4 slides axially relative to the extension 32 and slides to the maximum stroke position near the main body 31, the fastener 5 passes through the through holes and connects to the rotor 2, thereby fixing the rotor 2, the sleeve 3, and the shaft core 1.

[0068] Meanwhile, in this embodiment, the sleeve 3 is an elastic sleeve 3, made of a metal material with a certain elasticity, such as spring steel. When the locking ring 4 is connected to the sleeve 3, the compression of the sleeve 3 by the locking ring 4 causes the sleeve 3 to undergo a certain elastic bending, so as to increase the connection strength between the sleeve 3 and the rotor 2. When the rotor 2 and the sleeve 3 are in clearance fit, the elastic bending deformation of the sleeve 3 is greater than the fit clearance between the rotor 2 and the sleeve 3, so that the outer peripheral surface of the sleeve 3 can abut against the inner wall of the mounting hole of the rotor 2 and interact with each other.

[0069] The installation of the rotor 2 of this electric spindle is also relatively simple. The sleeve 3 is pre-installed on the shaft core 1, and the end of the extension 32 on one side of the sleeve 3 abuts against a shoulder 11 of the shaft core 1 to achieve stroke limitation in one direction. Then, the rotor 2 is installed and fitted into the sleeve 3. The locking rings 4 on both sides are installed and slid to the maximum stroke position. Finally, the fasteners 5 are installed to connect the locking rings 4 and the rotor 2 to complete the installation of the rotor 2. Example 2

[0070] See also Figure 3 and Figure 4 An electric spindle includes a spindle seat 10, which has a mounting cavity with openings on both sides. A stator 20 is fixed in the mounting cavity, and the electric spindle rotor mounting structure of Embodiment 1 is provided in the stator 20, so that the rotor 2 and the stator 20 cooperate with each other.

[0071] The electric spindle is also equipped with a front bearing assembly 7 and a rear bearing assembly 8, which are respectively distributed on both sides of the rotor 2, with the front bearing assembly 7 closer to the end where the workpiece is clamped. The front bearing assembly 7 includes a front bearing housing 71 mounted on the shaft core 1, several adjacent front bearings 72, a first front retaining ring 73, a first rear retaining ring 74, and a first locking nut 75.

[0072] The front bearing housing 71 is connected to the main shaft housing 10. Several front bearings 72 are placed inside the front bearing housing 71. The first front retaining ring 73 and the second rear retaining ring 84 are both installed on the shaft core 1. One end face of the first front retaining ring 73 abuts against one side of several front bearings 72 to limit the front bearings 72 in one axial direction. One end face of the first rear retaining ring 74 abuts against the other side of several front bearings 72 to limit the front bearings 72 in another axial direction. The first locking nut 75 is threaded to the shaft core 1 and abuts against the first rear retaining ring 74 to limit the axial movement of the first rear retaining ring 74.

[0073] The shaft core 1 is provided with a stop 12 extending radially away from the end near the workpiece clamping. The stop 12 abuts against one side of the first front retaining ring 73 to limit the axial movement of the first front retaining ring 73. In this embodiment, the stop 12 is integrally provided with the shaft core 1.

[0074] The electric spindle also includes a pull rod 6 disposed within the spindle core 1, a pull claw 9 connected to one end of the pull rod 6, a guide sleeve 40 disposed on the pull claw 9, and a front end cover 30. The pull rod 6 and the spindle core 1 cooperate to rotate synchronously, and the pull rod 6 can also slide axially relative to the spindle core 1. The pull claw 9 has a clamping hole for clamping the workpiece. The pull claw 9 has circumferentially arranged pull claw pieces, and there is a deformation groove between adjacent pull claw pieces. The guide sleeve 40 is placed outside the pull claw 9 and is connected to the stop 12 of the spindle core 1. When the pull rod 6 undergoes axial displacement relative to the spindle core 1, it drives the pull claw 9 to move axially. At this time, multiple pull claw pieces squeeze the inner wall of the guide sleeve 40 and shrink inward, thereby reducing the diameter of the clamping hole to clamp the workpiece. Conversely, the pull claw pieces return to their original position under their own elasticity, thereby increasing the diameter of the clamping hole to release the workpiece.

[0075] The front cover 30 is connected to the front bearing seat 71 and has an inner ring 301 extending toward the shaft core 1. The inner ring 301 has a first hook 3011 and the first front retaining ring 73 has a second hook 731. The first hook 3011 and the second hook 731 engage with each other to achieve positioning. At the same time, the inner ring 301 also abuts against one side of the front bearing 72. The inner ring 301 and the first front retaining ring 73 can jointly bear the axial force.

[0076] The rear bearing assembly 8 includes a rear bearing housing 81, a plurality of adjacently arranged rear bearings 82, a second front retaining ring 83, a second rear retaining ring 84, and a second locking nut 85. The plurality of rear bearings 82 are mounted on the shaft core 1 and placed inside the rear bearing housing 81. The second front retaining ring 83 and the second rear retaining ring 84 are also mounted on the shaft core 1. The second front retaining ring 83 abuts against one side of the plurality of rear bearings 82, and the second rear retaining ring 84 abuts against the other side of the plurality of rear bearings 82 to limit the axial movement of the rear bearings 82. At the same time, the second front retaining ring 83 also abuts against one end of the sleeve 3 to limit the axial movement of the sleeve 3. The second locking nut 85 is threaded to the shaft core 1 and abuts against one side of the second rear retaining ring to limit the axial movement of the second rear retaining ring 84. Example 3

[0077] A machine tool including the electric spindle of Embodiment 2.

[0078] The above are all preferred embodiments of this application, and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. An electric spindle rotor mounting structure, characterized in that, include: Shaft core (1); Rotor (2), wherein the rotor (2) has a through mounting hole; A sleeve (3) surrounds the outer peripheral wall of the shaft core (1) and passes through the mounting hole. The sleeve (3) can rotate synchronously with the shaft core (1), and both ends of the sleeve (3) extend out from the mounting hole; and Locking rings (4) are distributed at both ends of the rotor (2), and the locking rings (4) are connected to the rotor (2) by fasteners (5); The sleeve (3) includes a main body (31) and an extension (32) connected to both ends of the main body (31). The outer peripheral surface of the extension (32) is a first conical surface (321). The locking ring (4) has an inner hole. The inner peripheral surface of the inner hole is a second conical surface (41). The extension (32) enters the inner hole and the first conical surface (321) and the second conical surface (41) abut against each other.

2. The electric spindle rotor mounting structure according to claim 1, characterized in that, The jacket (3) is an elastic jacket.

3. The mounting structure of the electric spindle rotor (2) according to claim 1, characterized in that, The shaft core (1) is a stepped shaft with a shoulder (11), and one end of the sleeve (3) abuts against the shoulder (11).

4. An electric spindle, characterized in that, include: Spindle seat (10), the spindle seat (10) having a mounting cavity with openings at both ends; The stator (20) is located in the inner wall of the mounting cavity; as well as According to any one of claims 1-3, the rotor (2) is inserted into the stator (20).

5. The electric spindle according to claim 4, characterized in that, It also includes a front bearing assembly (7), which comprises: Front bearing housing (71), which is connected to the main shaft housing (10); Several front bearings (72) are mounted on the shaft core (1) and placed inside the front bearing housing (71); The first front retaining ring (73) is mounted on the shaft core (1) and one end face of the first front retaining ring (73) is adjacent to one side of a plurality of front bearings (72); A first rear retaining ring (74) is mounted on the shaft core (1), and one end face of the first rear retaining ring (74) abuts against the other side of a plurality of front bearings (72); and The first locking nut (75) is threaded onto the shaft core (1) and abuts against the first rear retaining ring (74). The shaft core (1) includes a stop (12) extending radially from its end, the stop (12) abutting against the first front retaining ring (73).

6. The electric spindle according to claim 4, characterized in that, It also includes a rear bearing assembly (8), which comprises: Rear bearing housing (81), which is connected to the main shaft housing (10); Several rear bearings (82) are mounted on the shaft core (1) and placed inside the rear bearing housing (81); The second front retaining ring (83) is installed on the shaft core (1) and the two end faces of the second front retaining ring (83) respectively abut against one side of a plurality of front bearings (72) and the end face of the extension (32); The second rear retaining ring (84) is mounted on the shaft core (1), and one end face of the second rear retaining ring (84) abuts against the other side of a plurality of front bearings (72); and The second locking nut (85) is threaded onto the shaft core (1) and abuts against the second rear retaining ring (84).

7. The electric spindle according to claim 5, characterized in that, It also includes a front end cap (30) connected to a front bearing housing (71), the front end cap (30) including an inner ring (301) extending toward the shaft core (1), one side of the inner ring (301) abutting against one side of a plurality of front bearings (72), one end of the inner ring (301) being connected to a first front retaining ring (73).

8. The electric spindle according to claim 7, characterized in that, The inner ring (301) has a first hook (3011), and the first front retaining ring (73) has a second hook (731), and the first hook (3011) and the second hook (731) engage with each other.

9. The electric spindle according to claim 5, characterized in that, Also includes: The pull rod (6) is inserted into the shaft core (1) and can rotate synchronously with the shaft core (1); A pull claw (9) is connected to one end of the pull rod (6) and extends out from the shaft core (1); as well as Guide sleeve (40) is connected to the stop; The pull claw (9) is located inside the guide sleeve (40) and can be axially displaced relative to the guide sleeve (40). The pull claw (9) has a clamping hole. When the pull claw (9) is axially displaced relative to the guide sleeve (40), the diameter of the clamping hole can be increased or decreased.

10. A machine tool, characterized in that, Including the electric spindle as described in claim 4.

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