Electric spindle

Abstract

The utility model discloses an electric spindle which comprises a machine body assembly, a spindle core, a pulling claw assembly and a tool loosening and broaching mechanism, the pulling claw assembly comprises a sliding core, a clamping connector is arranged at the rear end of the sliding core, the tool loosening and broaching mechanism comprises a first driving cylinder, a second driving cylinder and a pull rod, and the first driving cylinder is arranged at the rear end of the machine body assembly. The second driving cylinder is arranged at the rear end of the first driving cylinder, an axial connecting rod for transmitting axial force is arranged between a piston of the first driving cylinder and a piston of the second driving cylinder, the rear end of the pull rod is connected to the piston of the first driving cylinder, the front end of the pull rod extends into an inner hole of the shaft core, a clamping groove is formed in the front end of the pull rod, and the clamping connector is connected to the clamping groove. The clamping groove is provided with a clamping face capable of pulling the clamping head from the front side and an abutting face capable of abutting against the clamping head from the rear side, and an axial interval allowing the clamping head to move in the axial direction is formed between the abutting face and the clamping face. By adopting a disc-spring-free type locking structure, the problem of cutter loosening caused by failure of a disc spring is solved.

Description

TECHNICAL FIELD

[0001] The utility model relates to a machining spindle technical field, in particular to an electric spindle. BACKGROUND

[0002] With the demand of economic development and technology soaring, more and more new technologies emerge in an endless stream, and the mechanical processing industry also emerges in an endless stream, especially the leading spindle industry technology innovation is very obvious. Because the forming processing of automobile optical mold and the precision of high light industry are higher and higher, the spindle is forced to develop towards high speed and high precision. The traditional ball bearing electric spindle is limited by the bearing, and its speed and precision are difficult to further improve. Therefore, the high speed and high precision of the spindle industry must be researched and developed on the air floating spindle. Because the air floating bearing has the characteristics of low friction, low loss and error homogenization, the spindle adopting the air floating bearing becomes one of the best carriers to realize super precision machining.

[0003] However, the air floating spindle generally adopts elastic components such as disc springs to tighten the tool holder, and the tool holder tightening mode has the problem of loose tool caused by disc spring failure.

[0004] In addition, the existing electric spindle has congenital defects due to its structural arrangement, so that its speed and precision are difficult to further improve. Moreover, the spindle stator and shaft core generate a large amount of heat during high-speed rotation, and how to effectively remove the heat is also a difficulty. UTILITY MODEL CONTENTS

[0005] The utility model discloses a kind of electric spindles, to at least solve one of the technical problems existing in prior art.

[0006] The utility model discloses the technical scheme to solve its technical problem is as follows:

[0007] An electric spindle, comprising a machine body assembly, a shaft core, a pawl assembly and a loose tool mechanism, the shaft core is rotatably installed on the machine body assembly, the shaft core is provided with a shaft core inner hole, the pawl assembly is arranged at the front end of the shaft core inner hole, the pawl assembly comprises a sliding core, the rear end of the sliding core is provided with a clamping joint, the loose tool mechanism comprises a first drive cylinder, a second drive cylinder and a pull rod, the first drive cylinder is arranged at the rear end of the machine body assembly, the second drive cylinder is arranged at the rear end of the first drive cylinder, the piston of the first drive cylinder and the piston of the second drive cylinder are provided with an axial connecting rod for transmitting axial force, the rear end of the pull rod is connected to the piston of the first drive cylinder, the front end of the pull rod extends into the shaft core inner hole, the front end of the pull rod is provided with a clamping groove, the clamping joint is connected to the clamping groove, the clamping groove is provided with a clamping surface capable of pulling the clamping joint from the front side and a pushing surface capable of abutting against the clamping joint from the rear side, and the pushing surface and the clamping surface form an axial interval for the clamping joint to move axially.

[0008] In some embodiments, the machine body assembly comprises a machine body, a stator mounting base, a first aerostatic bearing seat and a second aerostatic bearing seat, the machine body is provided with a machine body bore extending axially from a first end to a second end, the stator mounting base is mounted to the machine body bore at the first end of the machine body, the second aerostatic bearing seat is mounted to the machine body bore at the second end of the machine body, the first aerostatic bearing seat is arranged in the machine body bore and clamped between the stator mounting base and the second aerostatic bearing seat, the first aerostatic bearing seat is provided with a first radial aerostatic bearing, the second aerostatic bearing seat is provided with a second radial aerostatic bearing, the shaft core is supported by the first radial aerostatic bearing and the second radial aerostatic bearing on the machine body assembly, the shaft core is provided with a flying disc matched with the first thrust bearing assembly and the second thrust bearing assembly, the stator mounting base is provided with a motor cavity behind the first aerostatic bearing seat, the stator mounting base is provided with a stator in the motor cavity, the shaft core extends into the motor cavity and is provided with a rotor matched with the stator.

[0009] In some embodiments, the stator mounting base, the first aerostatic bearing seat and the second aerostatic bearing seat form an outer circumferential surface extending axially inside the machine body bore, the outer circumferential surface is in contact with the inner wall of the machine body bore, and the outer circumferential surface of the stator mounting base, the first aerostatic bearing seat and the second aerostatic bearing seat is provided with a cooling liquid groove extending continuously as a whole.

[0010] In some embodiments, the cooling liquid groove comprises a spiral groove, the spiral groove comprises an inlet cooling liquid groove and a return cooling liquid groove, the inlet cooling liquid groove extends from the first end to the second end of the machine body, and the return cooling liquid groove extends from the second end to the first end of the machine body, the stator mounting base is provided with a cooling liquid inlet communicated with the inlet cooling liquid groove, and the stator mounting base is provided with a cooling liquid outlet communicated with the return cooling liquid groove.

[0011] In combination with the above implementation, in some implementations, the first end of the first gas bearing seat has a first boss extending in the axial direction, the first gas bearing seat is provided with a first axial stepped surface outside the first boss, the stator mounting seat has a first sleeve portion extending in the axial direction, the first sleeve portion is sleeved on the first boss, the end of the first sleeve portion abuts against the first axial stepped surface, the first gas bearing seat and the stator mounting seat are provided with a first sealing ring, the second end of the first gas bearing seat has a second boss extending in the axial direction, the first gas bearing seat is provided with a second axial stepped surface outside the second boss, the second gas bearing seat has a second sleeve portion extending in the axial direction, the second sleeve portion is sleeved on the second boss, the end of the second sleeve portion abuts against the second axial stepped surface, and the first gas bearing seat and the second gas bearing seat are provided with a second sealing ring.

[0012] In combination with the above implementation, in some implementations, the first gas bearing seat and the second gas bearing seat are provided with honeycomb-shaped axial heat dissipation holes.

[0013] In combination with the above implementation, in some implementations, the first thrust bearing assembly and the second thrust bearing assembly each include a first thrust bearing annular part and a second thrust bearing annular part, the first thrust bearing annular part and the second thrust bearing annular part form flush axial thrust surfaces, and a throttling gap for thrust gas flow to be ejected is formed between the first thrust bearing annular part and the second thrust bearing annular part at the axial thrust surfaces.

[0014] In combination with the above implementation, in some implementations, the first radial gas bearing is interference-fitted in the first gas bearing seat and then integrally machined to form a shaft hole for mounting the shaft core, the second radial gas bearing is interference-fitted in the second gas bearing seat and then integrally machined to form a shaft hole for mounting the shaft core, and the first thrust bearing annular part and the second thrust bearing annular part are mounted in the first gas bearing seat and the second gas bearing seat and then integrally machined to form flush axial thrust surfaces.

[0015] In combination with the above implementation manners, in some implementation manners, the rear end of the stator mounting seat is provided with a recessed cavity extending forward in the axial direction, the first driving cylinder comprises a first cylinder cover arranged in the recessed cavity, the first cylinder cover defines a first piston cavity inside the recessed cavity, the piston of the first driving cylinder is arranged in the first piston cavity, the front end of the axial connecting rod is connected to the piston of the first driving cylinder, the rear end of the axial connecting rod extends to the direction of the second driving cylinder through the first cylinder cover, the second driving cylinder comprises a cylinder body and a second cylinder cover, the cylinder body is connected to the rear end of the recessed cavity, the cylinder body is provided with a second piston cavity, the piston of the second driving cylinder is arranged in the second piston cavity, and the piston of the second driving cylinder is provided with a push rod extending to the axial connecting rod through the second cylinder cover.

[0016] In combination with the above implementation manners, in some implementation manners, the front end of the shaft core inner hole is provided with a tool holder mounting hole, the pull claw assembly further comprises a pull claw fixing ring, an elastic component, a gasket and a plurality of pull claw components, the pull claw fixing ring is arranged in the shaft core inner hole, the pull claw fixing ring is provided with a plurality of pull claw mounting grooves in the circumferential direction, the plurality of pull claw components are inserted into the pull claw mounting grooves, the front end of the sliding core is inserted into the pull claw fixing ring, the gasket is arranged on the rear side of the pull claw component, the elastic component is sleeved on the sliding core and abuts against the gasket from the rear side, and the sliding core is provided with an avoiding groove matched with the pull claw.

[0017] One of the above technical solutions has at least one of the following advantages or beneficial effects: in the technical solution of the utility model, when the broach is performed, the piston of the first driving cylinder moves backward together with the pull rod, the pull rod pulls the clamping joint of the sliding core through the clamping surface of the clamping groove, the sliding core also moves backward, the tool holder is locked at the front end of the shaft core by further cooperating with the pull claw assembly, at this time, the first driving cylinder is depressurized, the second driving cylinder is actuated and moves the piston and the pull rod of the first driving cylinder a certain distance forward through the axial connecting rod, the clamping joint is separated from the clamping surface and the abutting surface on both sides, the pull rod and the sliding core are avoided from interfering with each other, and the shaft core can rotate in this state. When the tool is loosened, the piston of the first driving cylinder moves forward together with the pull rod, the abutting surface of the pull rod abuts against the sliding core and pushes the sliding core to move forward, the tool holder is loosened by further cooperating with the pull claw assembly, and the tool can be replaced. The technical solution of the utility model realizes the functions of loosening and broaching through the cooperation of the first driving cylinder and the second driving cylinder and the cooperation between the pull rod and the sliding core, and solves the problem of loosening caused by the failure of the disc spring through the adoption of the non-disc spring locking structure.

[0018] Additional aspects and advantages of the utility model will be partially given in the following description, partially will become obvious from the following description, or will be understood through the practice of the utility model. BRIEF DESCRIPTION OF DRAWINGS

[0019] The above and / or additional aspects and advantages of the present application will become apparent and more readily appreciated from the following description of the embodiments, taken in conjunction with the references to the following drawings, of which:

[0020] Figure 1 is a schematic structural diagram of an embodiment of the present application;

[0021] Figure 2 is a schematic diagram of the cooperation structure of the stator mounting seat, the first air floating bearing seat and the second air floating bearing seat of an embodiment of the present application;

[0022] Figure 3 is a schematic structural diagram of the first air floating bearing seat of an embodiment of the present application;

[0023] Figure 4 is a schematic structural diagram of the second air floating bearing seat of an embodiment of the present application;

[0024] Figure 5 is a schematic structural diagram of the loose puller mechanism of an embodiment of the present application;

[0025] Figure 6 is a schematic structural diagram of the shaft core and puller claw assembly of an embodiment of the present application;

[0026] Figure 7 is a schematic structural diagram of the first air floating bearing assembly of an embodiment of the present application;

[0027] Figure 8 is a schematic structural diagram of the second air floating bearing assembly of an embodiment of the present application. DETAILED DESCRIPTION

[0028] This part will describe the specific embodiments of the present application in detail, and the preferred embodiments of the present application are shown in the drawings, and the drawings are used to supplement the description of the text part of the specification, so that people can intuitively and visually understand each technical feature and the overall technical scheme of the present application, but it cannot be understood as the limitation of the protection scope of the present application.

[0029] In the present application, if the direction (up, down, left, right, front and back) is described, it is only for the convenience of describing the technical scheme of the present application, and is not intended to indicate or imply that the technical features referred to must have a specific orientation, be constructed and operated in a specific orientation, therefore it cannot be understood as the limitation of the present application.

[0030] In this utility model, "several" means one or more, "multiple" means two or more, "greater than," "less than," "exceeding," etc. are understood to exclude the stated number; "above," "below," "within," etc. are understood to include the stated number. In the description of this utility model, if "first" or "second" is used, it is only for the purpose of distinguishing technical features and should not be construed as indicating or implying relative importance or implicitly indicating the number of indicated technical features or the order of the indicated technical features.

[0031] In this utility model, unless otherwise explicitly defined, terms such as "set," "install," and "connect" should be interpreted broadly. For example, they can refer to a direct connection or an indirect connection through an intermediate medium; a fixed connection, a detachable connection, or an integrally formed connection; a mechanical connection, an electrical connection, or a connection capable of mutual communication; or the internal connection of two components or the interaction between two components. Those skilled in the art can reasonably determine the specific meaning of the above terms in this utility model based on the specific content of the technical solution.

[0032] in, Figure 1 and Figure 5 The reference direction coordinate system of this utility model embodiment is given below, in conjunction with Figure 1 and Figure 5 The embodiments of this utility model will be described in the directions shown.

[0033] See Figure 1 , Figure 5 , Figure 6The utility model discloses an electric main shaft, including machine body subassembly, axle core 600, pull claw subassembly 800 and loose pull sword mechanism 900, axle core 600 rotatablely installed in machine body subassembly, axle core 600 is equipped with axle core inner hole 603, pull claw subassembly 800 sets up in the front end of axle core inner hole 603, and with the front end of sword handle connection in axle core 600, pull claw subassembly 800 includes sliding core 801, and the rear end of sliding core 801 is equipped with joint 802, loose pull sword mechanism 900 includes first drive cylinder, second drive cylinder and pull rod 901, and first drive cylinder sets up in the rear end of machine body subassembly, and second drive cylinder sets up in the rear end of first drive cylinder, and the piston between first drive cylinder and the piston of second drive cylinder is equipped with the axial connecting rod 902 of transmission axial force, and the stroke of first drive cylinder is greater than the stroke of second drive cylinder, and the rear end of pull rod 901 is connected in the piston of first drive cylinder, and the front end of pull rod 901 extends into axle core inner hole 603, and the front end of pull rod 901 is equipped with the clamping groove, and joint 802 is connected in the clamping groove, and the clamping groove is equipped with the clamping surface 903 of being able to pull from the front side joint 802 and the resistance surface 904 of being able to from the rear side resistance joint 802, and the resistance surface 904 and clamping surface 903 between form the axial interval of the axial movement of joint 802. In other words, joint 802 can only be in contact with resistance surface 904 or only be in contact with clamping surface 903 or not be in contact with resistance surface 904 and clamping surface 903. First drive cylinder can adopt oil cylinder, cylinder etc., and the piston of first drive cylinder can be moved from the front end of first drive cylinder to the rear end of first drive cylinder or from the rear end of first drive cylinder to the front end of first drive cylinder in work, but cannot stay in the position between the front end and the rear end of first drive cylinder.

[0034] In combination Figure 1 , Figure 5The utility model discloses technical scheme, when carrying out draw knife, the piston of first drive cylinder carries draw bar 901 and moves back together, and draw bar 901 passes through the clamping surface 903 of card slot and holds the clamping joint 802 of sliding core 801, make sliding core 801 also move back together, further cooperate draw dog subassembly 800 and lock the handle of knife to the front end of axle core 600, first drive cylinder releases pressure at this time, and second drive cylinder acts and pushes the piston of first drive cylinder and draw bar 901 and moves forward a certain distance through axial connecting rod 902, make clamping joint 802 and the pushing surface 904 of two sides separate with clamping surface 903, make draw bar 901 and sliding core 801 between avoid interference, and axle core 600 can run under this state. When carrying out knife, the piston of first drive cylinder carries draw bar 901 and moves forward together, and the pushing surface 904 of draw bar 901 and sliding core 801 abut, and sliding core 801 also moves forward together is pushed, further cooperate draw dog subassembly 800 and loosen the handle of knife, can replace tool. The utility model discloses technical scheme first drive cylinder, second drive cylinder cooperates and acts, and the cooperation between draw bar 901 and sliding core 801 is combined simultaneously, realizes the function of loosening draw knife, and it passes through adopting no disc spring type locking structure, solves the loosening problem of draw knife caused by disc spring failure.

[0035] In some embodiments, referring to Figure 1 、 Figure 2The machine body assembly comprises a machine body sleeve 100, a stator mounting seat 200, a first air floating bearing seat 300 and a second air floating bearing seat 400. The machine body sleeve 100 is in the shape of a sleeve. The machine body sleeve 100 extends along an axial direction from a first end 101 to a second end 102. The machine body sleeve 100 is provided with a machine body inner hole 103 extending along the axial direction from the first end 101 to the second end 102. The stator mounting seat 200 is mounted in the machine body inner hole 103 at the first end 101 of the machine body sleeve 100. The stator mounting seat 200 can be connected to the machine body sleeve 100 in a threaded, pin or screw manner. The second air floating bearing seat 400 is mounted in the machine body inner hole 103 at the second end 102 of the machine body sleeve 100. The second air floating bearing seat 400 can be connected to the machine body sleeve 100 in a threaded, pin or screw manner. The first air floating bearing seat 300 is arranged in the machine body inner hole 103 and is clamped between the stator mounting seat 200 and the second air floating bearing seat 400. In other words, one end of the first air floating bearing seat 300 abuts against the stator mounting seat 200, and the other end of the first air floating bearing seat 300 abuts against the second air floating bearing seat 400. The first air floating bearing seat 300 is provided with a first radial air floating bearing 301. The second air floating bearing seat 400 is provided with a second radial air floating bearing 401. The first air floating bearing seat 300 is provided with a first thrust bearing assembly 302 at one end close to the second air floating bearing seat 400. The second air floating bearing seat 400 is provided with a second thrust bearing assembly 401 at one end close to the first air floating bearing seat 300. The shaft core 600 is supported on the machine body assembly through the first radial air floating bearing 301 and the second radial air floating bearing 401. The shaft core 600 is provided with a flying disc 601 matched with the first thrust bearing assembly 302 and the second thrust bearing assembly 401. Figure 7 The first radial air floating bearing 301 and the first thrust bearing assembly 302 are arranged in the first air floating bearing seat 300 to form a first air floating bearing assembly. Figure 8 The second radial air floating bearing 401 and the second thrust bearing assembly 401 are arranged in the second air floating bearing seat 400 to form a second air floating bearing assembly.

[0036] High-pressure air passes through the airflow channel of the machine body assembly and enters the damping plugs of the first radial air floating bearing 301 and the second radial air floating bearing 401. The damping plugs are micro-porous throttles with the same pore size. After passing through the micro-pores, the high-pressure air diffuses to the surrounding, so that a high-pressure air film is formed between the shaft core and the first radial air floating bearing 301 and the second radial air floating bearing 401. At the same time, the high-pressure air enters the slit throttles of the first thrust bearing assembly 302 and the second thrust bearing assembly 401, so that a high-pressure air film is also formed between the position of the flying disc of the shaft core and the thrust bearing assembly. The high-pressure air films existing between the first radial air floating bearing 301, the second radial air floating bearing 401, the thrust bearing assembly and the shaft core support the shaft core to be non-contact suspended and ensure that the shaft core has a certain load capacity and rigidity.

[0037] The stator mounting seat 200 is provided with a motor cavity 205 behind the first air floating bearing seat 300, the stator mounting seat 200 is provided with a stator 204 in the motor cavity 205, the shaft core 600 extends into the motor cavity 205 and is provided with a rotor 602 matched with the stator 204. The stator 204 forms a motor, for example, in some embodiments, the motor adopts a slotless permanent magnet synchronous motor, and the whole shaft core 600 is driven to rotate at high speed through the control of a driver.

[0038] In combination Figure 1 、 Figure 2 , the technical scheme of the utility model discloses that the stator mounting seat 200 and the second air floating bearing seat 400 are respectively installed at both ends of the machine body sleeve 100, and the first air floating bearing seat 300 is clamped through the stator mounting seat 200 and the second air floating bearing seat 400 on both sides, the motorized spindle machine body assembly adopts an integrated clamping structure design, reduces the assembly anomaly of parts, and is convenient for overall disassembly and dynamic balance. Meanwhile, the thrust bearing assembly is arranged between the first air floating bearing seat 300 and the second air floating bearing seat 400, that is, the shaft core flying disc center structure is formed, the spindle can obtain higher rigidity, the thrust bearing assembly is far away from the rotor position, the influence of thermal deformation on the shaft core is reduced, and the stability of the shafting is improved. The embodiment of the utility model improves the spindle rigidity and precision.

[0039] In some embodiments, referring to Figure 1 、 Figure 2 , the stator mounting seat 200, the first air floating bearing seat 300 and the second air floating bearing seat 400 form the outer side circumferential surface 500 continuously extending in the axial direction inside the machine body bore 103, and the outer side circumferential surface 500 is attached to the inner wall of the machine body bore 103. The outer side circumferential surface 500 of the stator mounting seat 200, the first air floating bearing seat 300 and the second air floating bearing seat 400 is matched with the machine body sleeve 100, and forms a stable overall structure, reduces the assembly anomaly of parts, and is convenient for overall disassembly and dynamic balance.

[0040] During the high-speed rotation of the spindle stator and the shaft core, a large amount of heat is generated, and how to effectively remove the heat is a difficulty, in some embodiments, referring to Figure 1 、 Figure 2 、 Figure 3 、 Figure 4The outer circumferential surface 500 of the stator mounting seat 200, the first air floating bearing seat 300 and the second air floating bearing seat 400 is provided with a cooling liquid groove 501 extending continuously as a whole, in other words, the cooling liquid groove 501 of the outer circumferential surface 500 of the stator mounting seat 200, the cooling liquid groove 501 of the outer circumferential surface 500 of the first air floating bearing seat 300 and the cooling liquid groove 501 of the outer circumferential surface 500 of the second air floating bearing seat 400 are connected in sequence to form a cooling liquid groove 501 extending continuously as a whole, and the cooling liquid groove 501 cooperates with the outer body sleeve 100 to form a cooling channel extending continuously, which is in overall communication with the outer circumferential surface 500 of the stator mounting seat 200, the first air floating bearing seat 300 and the second air floating bearing seat 400, so as to maximize the cooling area. This structure can maximize the heat of the spindle product to be taken out of the shaft in time, reduce the influence of heat on the shaft core during high-speed operation, and ensure the safety of high-speed operation of the spindle.

[0041] The cooling liquid groove 501 can be arranged on the outer circumferential surface 500 of the stator mounting seat 200, the first air floating bearing seat 300 and the second air floating bearing seat 400 in the shape of U or spiral, and in some embodiments, referring to Figure 2 The cooling liquid groove 501 includes a spiral groove, which spirally surrounds the outer circumferential surface 500 of the stator mounting seat 200, the first air floating bearing seat 300 and the second air floating bearing seat 400 and is in overall communication. The spiral groove includes an inlet cooling liquid groove and a return cooling liquid groove. The inlet cooling liquid groove extends from the first end 101 to the second end 102 of the body sleeve 100, and the return cooling liquid groove extends from the second end 102 to the first end 101 of the body sleeve 100. The stator mounting seat 200 is provided with a cooling liquid inlet 201 in communication with the inlet cooling liquid groove, and the stator mounting seat 200 is provided with a cooling liquid outlet 202 in communication with the return cooling liquid groove. During operation, the cooling liquid enters through the cooling liquid inlet 201, flows through the inlet cooling liquid groove and the return cooling liquid groove, and then flows out through the cooling liquid outlet, so as to take out the heat of the spindle product out of the shaft in time, reduce the influence of heat on the shaft core assembly during high-speed operation, and ensure the safety of high-speed operation of the spindle.

[0042] In some embodiments, referring to Figure 1, the first end of the first gas bearing seat 300 has a first boss 303 extending in the axial direction, the first gas bearing seat 300 is provided with a first axial stepped surface 304 outside the first boss 303, the stator mounting seat 200 has a first sleeve part 203 extending in the axial direction, the first sleeve part 203 is sleeved on the first boss 303, the end of the first sleeve part 203 abuts against the first axial stepped surface 304, and the first gas bearing seat 300 and the stator mounting seat 200 are provided with a first sealing ring. The first gas bearing seat 300 and the stator mounting seat 200 are connected in a radial sleeving and axial abutting mode, so that the assembly precision between the first gas bearing seat 300 and the stator mounting seat 200 is fully ensured. Meanwhile, the first sealing ring is used to ensure the sealing between the first gas bearing seat 300 and the stator mounting seat 200, so that the cooling liquid is prevented from leaking between the first gas bearing seat 300 and the stator mounting seat 200.

[0043] In some embodiments, referring to Figure 1 , the second end of the first gas bearing seat 300 has a second boss 305 extending in the axial direction, the first gas bearing seat 300 is provided with a second axial stepped surface 306 outside the second boss 305, the second gas bearing seat 400 has a second sleeve part 402 extending in the axial direction, the second sleeve part 402 is sleeved on the second boss 305, and the end of the second sleeve part 402 abuts against the second axial stepped surface 306, and the first gas bearing seat 300 and the second gas bearing seat 400 are provided with a second sealing ring. The second gas bearing seat 400 and the first gas bearing seat 300 are connected in a radial sleeving and axial abutting mode, so that the assembly precision between the first gas bearing seat 300 and the second gas bearing seat 400 is fully ensured. Meanwhile, the second sealing ring is used to ensure the sealing between the first gas bearing seat 300 and the second gas bearing seat 400, so that the cooling liquid is prevented from leaking between the first gas bearing seat 300 and the second gas bearing seat 400.

[0044] In some embodiments, referring to Figure 3 , Figure 4 , the first gas bearing seat 300 and the second gas bearing seat 400 are provided with honeycomb-shaped axial heat dissipation holes 307 and 403, so that the heat dissipation area is further increased, the influence of heat on the high-speed operation of the shaft core assembly is further reduced, and the safety of the high-speed operation of the main shaft is ensured.

[0045] In some embodiments, referring to Figure 1The first gas bearing seat 300 is provided with a first flange 308 matched with the axial end face of the first end of the body sleeve 100, the first flange 308 is located outside the inner hole 103 of the body, the first flange 308 is assembled to the first end of the body sleeve 100 through a first fastener 309, and the first fastener 309 can be a screw, a bolt or the like. Similarly, the second gas bearing seat 400 is provided with a second flange 404 matched with the axial end face of the second end of the body sleeve 100, the second flange 404 is located outside the inner hole 103 of the body, the second flange 404 is assembled to the second end of the body sleeve 100 through a second fastener 405, and the second fastener can be a screw, a bolt or the like. In this embodiment, the first fastener 309 and the second fastener 405 are locked in the axial direction, so that the stator mounting seat 200, the first gas bearing seat 300 and the second gas bearing seat 400 can be integrally clamped in the body sleeve 100.

[0046] The first thrust bearing assembly 302 and the second thrust bearing assembly 401 are used to cooperate with the flying disc of the shaft core, so that a high-pressure gas film is also formed between the flying disc position and the thrust bearing assembly.

[0047] In some embodiments, referring to Figure 1 、 Figure 7 、 Figure 8 The first thrust bearing assembly 302 and the second thrust bearing assembly 401 each include a first thrust bearing annular part 310, 406 and a second thrust bearing annular part 311, 407, the first thrust bearing annular part 310, 406 and the second thrust bearing annular part 311, 407 form flush axial thrust faces, and a throttle gap 312, 408 for jetting thrust gas is formed between the first thrust bearing annular part 310, 406 and the second thrust bearing annular part 311, 407 at the axial thrust face. In this embodiment, the throttle gap for jetting thrust gas is formed through the cooperation gap between the first thrust bearing annular part and the second thrust bearing annular part, the structure is simpler, it is not necessary to provide axial damping holes on the first thrust bearing assembly 302 and the second thrust bearing assembly 401, and the throttle gap can continuously extend in the circumferential direction, so that a better high-pressure gas film can be obtained.

[0048] The throttle gap 312, 408 can extend in a circular or wavy shape in the circumferential direction, and in some embodiments, referring to Figure 7 、 Figure 8, the first thrust bearing ring member 310, 406 is provided with an outer circumferential surface, the second thrust bearing ring member 311, 407 is provided with an inner circumferential surface, the second thrust bearing ring member 311, 407 is sleeved on the first thrust bearing ring member 310, 406, and the outer circumferential surface of the first thrust bearing ring member 310, 406 is coaxial with the inner circumferential surface of the second thrust bearing ring member 311, 407, so that the throttling gap 312, 408 with better uniformity is more easily obtained, and the air floating thrust bearing has uniform axial air film stiffness in the circumferential direction.

[0049] In some embodiments, referring to Figures 7-8 , the first thrust bearing ring member 310, 406 is provided with a radial flange 312, 409 abutting against the second thrust bearing ring member 311, 407 in the axial direction from the rear side. The first thrust bearing ring member 310, 406 forms a groove space on the front side of the radial flange 316, 409, and the second thrust bearing ring member 311, 407 can be installed in the groove space to achieve accurate positioning and stable installation in the axial and radial directions.

[0050] Further, referring to Figures 7-8 , the first thrust bearing assembly 302 and the second thrust bearing assembly 401 are installed in the first air floating bearing seat 300 and the second air floating bearing seat 400 by corresponding screws, the radial flange 316, 409 and the second thrust bearing ring member 311, 407 are provided with axial screw holes at corresponding positions, the axial screw hole of the radial flange 316, 409 is a through hole, the axial screw hole of the second thrust bearing ring member 311, 407 is a blind hole, the screw passes through the axial screw hole of the radial flange 316, 409 and is connected to the axial screw hole of the second thrust bearing ring member 311, 407, and locks the first thrust bearing ring member 310, 406 and the second thrust bearing ring member 311, 407 to the first air floating bearing seat 300 and the second air floating bearing seat 400, and the first thrust bearing ring member 310, 406 and the second thrust bearing ring member 311, 407 are integrally machined to form flush axial thrust surfaces. In this embodiment, the first thrust bearing ring member 310, 406 and the second thrust bearing ring member 311, 407 are integrally machined after assembly, which can effectively improve the shape and position tolerances of the bearing in the radial and axial directions, and improve the precision and stability of the air floating bearing.

[0051] In some embodiments, referring to Figure 7 , Figure 8, the outer circumferential surface of the first thrust bearing ring member 310, 406 is provided with a first ring groove 313, 410 and a plurality of air inlet holes 314, 411 communicating with the first ring groove 313, 410, the air inlet holes 314, 411 extend to the tail end surface of the first thrust bearing ring member 310, 406, the tail end surface of the first thrust bearing ring member 310, 406 is provided with a second ring groove 315, 412 communicating with the air inlet hole 314, 411, the second ring groove 315, 412, the air inlet hole 314, 411 and the first ring groove 313, 410 form an air inlet channel. The air inlet channel of the embodiment can fully ensure the uniformity of the overflow gas flow from the throttle gap.

[0052] Further, referring to Figure 7 、 Figure 8 , the first ring groove 313, 410 divides the outer circumferential surface of the first thrust bearing ring member 310, 406 into a first outer circumferential surface and a second outer circumferential surface along the axial direction, the first outer circumferential surface is closer to the axial thrust surface than the second outer circumferential surface, the inner circumferential surface of the second thrust bearing ring member 311, 407 is in clearance fit with the first outer circumferential surface, and the inner circumferential surface of the second thrust bearing ring member 311, 407 is in interference fit with the second outer circumferential surface. The interference fit between the first thrust bearing ring member 310, 406 and the second thrust bearing ring member 311, 407 is adopted at the second outer circumferential surface, so as to further ensure the uniformity of the throttle gap between the first thrust bearing ring member 310, 406 and the second thrust bearing ring member 311, 407 at the first outer circumferential surface.

[0053] In some embodiments, referring to Figure 7 、 Figure 8 , the first radial air floating bearing 301 is interference fitted in the first air floating bearing seat 300 and then integrally machined to form a shaft hole of the mounting shaft core 600, and the second radial air floating bearing 401 is interference fitted in the second air floating bearing seat 400 and then integrally machined to form a shaft hole of the mounting shaft core 600. The embodiment adopts the scheme of assembling first and then machining, which can effectively improve the perpendicularity of the radial and axial directions of the bearing, and improve the spindle stiffness, precision, etc.

[0054] In some embodiments, referring to Figure 5The rear end of the stator mounting base 200 is provided with a concave cavity 206 extending forward along the axial direction, the first driving cylinder includes a first cylinder cover 905 arranged in the concave cavity 206, the first cylinder cover 905 defines a first piston cavity 906 inside the concave cavity 206, a piston 907 of the first driving cylinder is arranged in the first piston cavity 906, the front end of the axial connecting rod 902 is connected to the piston 907 of the first driving cylinder, the rear end of the axial connecting rod 902 extends to the direction of the second driving cylinder through the first cylinder cover 905, the second driving cylinder includes a cylinder body 908 and a second cylinder cover 909, the cylinder body 908 is connected to the rear end of the concave cavity 206, the cylinder body 908 is provided with a second piston cavity 910, a piston 911 of the second driving cylinder is arranged in the second piston cavity 910, the piston 911 of the second driving cylinder is provided with a push rod 912 extending to the axial connecting rod 902 through the second cylinder cover 909. In the embodiment, the first driving cylinder and the second driving cylinder are arranged in the concave cavity 206 of the stator mounting base 200, which can effectively shorten the axial length of the whole motorized spindle, the structure is more compact, and the coordinated action can be better guaranteed.

[0055] In some embodiments, referring to Figure 6 The front end of the shaft core inner hole 603 is provided with a tool handle mounting hole, the tool handle mounting hole is a tapered hole, the pull claw assembly further includes a pull claw fixing ring 803, an elastic component 804, a gasket 805 and a plurality of pull claw components 806, the pull claw fixing ring 803 is mounted in the shaft core inner hole 603, the pull claw fixing ring 803 is provided with a plurality of pull claw mounting grooves in the circumferential direction, the plurality of pull claw components 806 are inserted into the pull claw mounting grooves, the front end of the sliding core 801 is inserted into the pull claw fixing ring 803, the gasket 805 is arranged on the rear side of the pull claw component 806, the elastic component 804 is sleeved on the sliding core 801 and abuts against the gasket 805 from the rear side, the elastic component 804 is used for pre-tightening each part of the pull claw assembly as a whole, facilitating assembly in the shaft core, and the sliding core 801 is provided with an avoidance groove matched with the pull claw.

[0056] When the front cavity of the first driving cylinder is communicated with high-pressure gas, the piston 907 moves backward together with the pull rod 901, the pull rod 901 is connected with the sliding core 801 through the clamping groove, and the sliding core 801 also moves backward together, when the sliding core 801 moves backward, the inner side of the pull claw is scattered from the corresponding avoidance groove on the sliding core 801, one end of the outer side of the pull claw is clamped into the corresponding inclined groove of the tool handle, the sliding core 801, the pull claw and the tool handle 807 are locked due to deformation, and the tool handle is in the locked state. When the rear cavity of the first driving cylinder is communicated with high-pressure gas, the piston moves forward together with the pull rod 901, the pull rod 901 is connected with the sliding core 801 through the clamping groove, and the sliding core 801 also moves forward together, when the sliding core 801 moves forward, the inner side of the pull claw slides into the avoidance groove along the corresponding position matched with the sliding core 801, one end of the pull claw avoids the inclined groove of the tool handle, and the tool handle can be loosened and the tool can be replaced.

[0057] It can be understood that the claw assembly can also adopt a steel column claw, an integrated claw and the like.

[0058] In some embodiments, referring to Figure 1 The electric spindle is provided with a cover plate 700 at the end of the electric spindle body assembly, and a small gap 701 is left between the cover plate 700 and the front end of the shaft core 600. The gas in the system can flow to the outside through the gap, and the gap also functions as a gas seal to prevent dust from entering the interior of the spindle during machining, thereby prolonging the service life of the spindle. Meanwhile, the cover plate 700 can also blow away the residual on the surface of the workpiece, thereby improving the surface machining effect.

[0059] In the description of the present specification, the description of the terms "example", "embodiment" or "some embodiments" and the like means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are contained in at least one embodiment or example of the present application. In the present specification, the illustrative description of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0060] Of course, the present application is not limited to the above-mentioned embodiments, and those skilled in the art can make equivalent modifications or replacements without departing from the spirit of the present application. These equivalent modifications or replacements are all included in the scope defined by the claims of the present application.

Claims

1. An electric spindle, characterized in that, The device includes a body assembly, a shaft core, a pull claw assembly, and a puller release mechanism. The shaft core is rotatably mounted on the body assembly and has an inner hole. The pull claw assembly is located at the front end of the inner hole and includes a sliding core. A retaining connector is located at the rear end of the sliding core. The puller release mechanism includes a first drive cylinder, a second drive cylinder, and a pull rod. The first drive cylinder is located at the rear end of the body assembly, and the second drive cylinder is located at the rear end of the first drive cylinder. An axial connecting rod for transmitting axial force is provided between the pistons of the first and second drive cylinders. The rear end of the pull rod is connected to the piston of the first drive cylinder, and the front end of the pull rod extends into the inner hole of the shaft core. The front end of the pull rod has a retaining groove, and the retaining connector is connected to the retaining groove. The retaining groove has a retaining surface that can pull the retaining connector from the front and a pushing surface that can abut against the retaining connector from the rear. An axial gap is formed between the pushing surface and the retaining surface to allow the retaining connector to move axially.

2. The electric spindle according to claim 1, characterized in that, The body assembly includes a body outer casing, a stator mounting base, a first air bearing housing, and a second air bearing housing. The body outer casing has an internal bore extending axially from a first end to a second end. The stator mounting base is mounted into the internal bore from the first end of the body outer casing. The second air bearing housing is mounted into the internal bore from the second end of the body outer casing. The first air bearing housing is disposed within the internal bore and clamped between the stator mounting base and the second air bearing housing. The first air bearing housing has a first radial air bearing, and the second air bearing housing has a second radial air bearing. A first air bearing housing has a first thrust bearing assembly at one end near the second air bearing housing, and a second air bearing housing has a second thrust bearing assembly at one end near the first air bearing housing. The shaft is supported on the body assembly by the first radial air bearing and the second radial air bearing. The shaft has a fly disc that mates with the first thrust bearing assembly and the second thrust bearing assembly. The stator mounting base has a motor cavity behind the first air bearing housing. The stator mounting base has a stator in the motor cavity. The shaft extends into the motor cavity and has a rotor that mates with the stator.

3. The electric spindle according to claim 2, characterized in that, The stator mounting base, the first air bearing housing, and the second air bearing housing form an outer circumferential surface that extends continuously along the axial direction inside the inner bore of the machine body. The outer circumferential surface is in contact with the inner wall of the inner bore of the machine body. The outer circumferential surface of the stator mounting base, the first air bearing housing, and the second air bearing housing is provided with an integrally continuous coolant tank.

4. The electric spindle according to claim 3, characterized in that, The coolant tank includes a spiral groove, which includes an inlet coolant tank and a return coolant tank. The inlet coolant tank extends from a first end to a second end of the outer casing, and the return coolant tank extends from a second end to a first end of the outer casing. The stator mounting base is provided with a coolant inlet communicating with the inlet coolant tank, and the stator mounting base is provided with a coolant outlet communicating with the return coolant tank.

5. The electric spindle according to claim 2, characterized in that, The first air bearing housing has a first boss extending axially at its first end, and a first axial stepped surface on the outer side of the first boss. The stator mounting seat has a first sleeve portion extending axially, which is fitted onto the first boss. The end of the first sleeve portion abuts against the first axial stepped surface. A first sealing ring is provided between the first air bearing housing and the stator mounting seat. The second air bearing housing has a second boss extending axially at its second end, and a second axial stepped surface on the outer side of the second boss. The second air bearing housing has a second sleeve portion extending axially, which is fitted onto the second boss. The end of the second sleeve portion abuts against the second axial stepped surface. A second sealing ring is provided between the first air bearing housing and the second air bearing housing.

6. The electric spindle according to claim 2, characterized in that, The first and second air bearing housings are provided with honeycomb-shaped axial heat dissipation holes.

7. The electric spindle according to claim 2, characterized in that, Both the first thrust bearing assembly and the second thrust bearing assembly include a first thrust bearing annular component and a second thrust bearing annular component. The first thrust bearing annular component and the second thrust bearing annular component form a flush axial thrust surface. A throttling slot for thrust airflow is formed between the first thrust bearing annular component and the second thrust bearing annular component on the axial thrust surface.

8. The electric spindle according to claim 7, characterized in that, The first radial air bearing is interference-fitted into the first air bearing housing and then machined as a whole to form a shaft hole for mounting the shaft core. The second radial air bearing is interference-fitted into the second air bearing housing and then machined as a whole to form a shaft hole for mounting the shaft core. The first thrust bearing annular component and the second thrust bearing annular component are installed into the first air bearing housing and the second air bearing housing and then machined as a whole to form a flush axial thrust surface.

9. The electric spindle according to claim 2, characterized in that, The stator mounting base has a recessed cavity extending forward along the axial direction at its rear end. The first drive cylinder includes a first cylinder head disposed in the recessed cavity. The first cylinder head defines a first piston chamber inside the recessed cavity. The piston of the first drive cylinder is disposed in the first piston chamber. The front end of the axial connecting rod is connected to the piston of the first drive cylinder. The rear end of the axial connecting rod extends through the first cylinder head toward the second drive cylinder. The second drive cylinder includes a cylinder body and a second cylinder head. The cylinder body is connected to the rear end of the recessed cavity. The cylinder body has a second piston chamber. The piston of the second drive cylinder is disposed in the second piston chamber. The piston of the second drive cylinder has a push rod extending through the second cylinder head toward the axial connecting rod.

10. The electric spindle according to claim 1, characterized in that, The front end of the inner hole of the shaft core is provided with a tool holder mounting hole. The pull claw assembly also includes a pull claw fixing ring, an elastic component, a washer, and multiple pull claw components. The pull claw fixing ring is installed in the inner hole of the shaft core. The pull claw fixing ring is provided with multiple pull claw mounting grooves along the circumference. Multiple pull claw components are inserted into the pull claw mounting grooves. The front end of the sliding core is inserted into the pull claw fixing ring. The washer is located on the rear side of the pull claw component. The elastic component is fitted onto the sliding core and abuts against the washer from the rear side. The sliding core is provided with a clearance groove that cooperates with the pull claw.

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