Universal main shaft and numerical control machining center using same

Abstract

The invention relates to the technical field of electric spindles, in particular to a universal spindle and a numerical control machining center using the universal spindle, which comprises a sleeve, a stator arranged in the sleeve, a rotor arranged in the stator, a mandrel arranged in the rotor in a penetrating manner and provided with a hollow cavity, and a pull rod matched with the hollow cavity of the mandrel, an oil cylinder assembly is arranged at one shaft side end of the mandrel and comprises a cylinder barrel connected with the sleeve, a cylinder cover connected with the end, away from the sleeve, of the cylinder barrel and a piston arranged in the cylinder barrel. One end of the pull rod extends into the cylinder barrel, an upper blowing transition seat suitable for abutting against the piston is arranged at the end, extending into the cylinder barrel, of the pull rod, and the portion, away from the cylinder barrel, of the pull rod is sleeved with a lower blowing transition seat; air channels suitable for air circulation are formed among the upper blowing transition seat, the outer side wall of the pull rod and the inner cavity wall of the mandrel and among the lower blowing transition seats; and the cylinder cover is provided with an air inlet group for introducing air into the cylinder barrel and an oil inlet group for introducing oil into the cylinder barrel.

Description

Technical Field

[0001] The invention relates to the technical field of electric spindles, and in particular to a universal spindle and a CNC machining center using the same. Background Art

[0002] The continuous maturity of advanced manufacturing technology has put forward higher requirements for CNC machining technology and higher performance indicators for machine tool structures. Mechanical products are becoming more and more sophisticated and complex. The use of ordinary machine tools or highly specialized automated machine tools to process such products can no longer meet these requirements. A new type of machine tool, the machining center, has emerged. The machining center has the advantages of strong adaptability, high machining accuracy, stable machining quality and high production efficiency. Therefore, its application is gradually becoming more widespread. The spindle is one of the core components of the machining center. The spindle is a relatively independent component from the machine tool's transmission system and overall structure, and can independently realize the functions of the machine tool spindle and spindle motor.

[0003] The spindle, as one of the core components of the machining center, is widely used in the prior art in three-axis machining centers and five-axis machining centers. However, the current machining centers are still lacking in the universality of the spindle. Generally, the spindle applicable to the three-axis machining center cannot be applicable to the five-axis machining center. In this case, it is necessary to use a spindle corresponding to each different machining center. For example, a large-load, high-rigidity permanent magnet synchronous electric spindle disclosed in publication number CN110539006A, the oil port corresponding to the oil cylinder used in it can only be applied to the three-axis machining center, because the spindle can only be used in a vertical state at this time, and for the five-axis machining center, some need to be in a vertical state, and some need to be in a horizontal state. Therefore, the spindle that can only be used vertically cannot meet the use requirements of all five-axis machining centers.

[0004] In addition, by setting a central air path in the pull rod, the tool handle is blown out by the airflow blown out of the central air path when the tool is released, and the central air path has the function of assisting the unloading of the tool. In the above structure, the outer wall of the rotor matched therewith is provided with an annular "T"-shaped air path. When the tool is released, the pull rod pushes the front connecting rod to move forward, so that the central air path is aligned with the hole of the rotor wall. The central air path passes through the air path and enters the air path of the outer wall of the rotor, and then blows out from the end face of the rotor. At the same time, the flange surface and the center of the tool handle are blown synchronously to better clean the end face of the tool handle. In this case, for the case where the tool handle needs to be cooled during the processing, it is also necessary to pass the coolant into the central air path, so that the coolant flows into the tool handle. For this case, on the one hand, it is necessary to configure a switching valve that can switch the coolant and gas passed into the central air path; on the other hand, if the sealing match between the central air path and the hole of the rotor wall cannot be ensured during the liquid flow, the liquid will have an unexpected overflow problem.

[0005] Therefore, in view of the problems existing in the use of the spindle in the prior art, it is necessary to further optimize the structure of the spindle. Summary of the invention

[0006] The first object of the present invention is to provide a universal spindle to solve the technical problem of optimizing its overall performance.

[0007] The second object of the present invention is to provide a CNC machining center to solve the technical problem of optimizing its overall performance.

[0008] The universal spindle of the present invention is achieved in this way: A universal spindle comprises: a sleeve and a stator arranged in the sleeve, a rotor arranged in the stator, a core shaft with a hollow cavity arranged in the rotor, and a pull rod matched with the hollow cavity of the core shaft; wherein A cylinder assembly is provided at one axial side end of the core shaft, and the cylinder assembly includes a cylinder barrel connected to the sleeve, a cylinder cover connected to one end of the cylinder barrel away from the sleeve, and a piston arranged in the cylinder barrel; The pull rod is suitable for sliding along the axial direction of the core shaft; one end of the pull rod extends into the cylinder, and an upper air blowing transition seat suitable for abutting against the piston is provided at the end of the pull rod extending into the cylinder, and a lower air blowing transition seat is sleeved on the part of the pull rod away from the cylinder; an air channel suitable for gas circulation is formed between the upper air blowing transition seat, the outer wall of the pull rod and the inner cavity wall of the core shaft, and between the lower air blowing transition seat; and The cylinder head is provided with an air inlet group for ventilating air into the cylinder barrel and an oil inlet group for ventilating oil into the cylinder barrel; the piston is provided with a central through hole connecting the air inlet group and the air passage; the air inlet group includes a first air inlet and a first oil inlet provided on the end face of the cylinder head along the axial direction of the rotor, and the oil inlet group includes a second air inlet and a second oil inlet provided on the side wall of the cylinder head perpendicular to the axial direction of the rotor.

[0009] In an optional implementation of the present invention, an exhaust passage connected to the airway is provided in a portion of the core shaft away from the oil cylinder.

[0010] In an optional implementation of the present invention, a hollow liquid channel is provided inside the pull rod and penetrates the pull rod along the axial direction of the rotor; and The upper air blowing transition seat is provided with a connecting pipe for connecting the hollow liquid channel and for passing liquid; The cylinder cover is also equipped with a joint which partially extends into the cylinder barrel and is used to be connected with a connecting pipe.

[0011] In an optional implementation of the present invention, a spring support is provided between the outer wall of the pull rod and the inner wall of the core shaft; and A plurality of support rings are also provided between the outer wall of the pull rod and the inner wall of the core shaft and are arranged at intervals along the axial direction of the rotor; Each supporting ring is provided with a through hole penetrating along the axial direction of the rotor and suitable for air flow to pass through.

[0012] In an optional embodiment of the present invention, the piston comprises a columnar portion adapted to abut against the upper air blowing transition seat, and an annular portion connected to one end of the columnar portion facing the cylinder head; wherein The annular portion is folded toward the outside of the columnar portion; An elastic supporting member is arranged between the cylinder barrel and the side end of the annular portion facing away from the cylinder cover.

[0013] In an optional implementation of the present invention, an indicator is further provided on a side of the annular portion facing away from the cylinder head; A proximity switch for sensing the indicator is arranged on the side wall of the cylinder.

[0014] In an optional implementation of the present invention, the upper air blowing transition seat is a frustum-shaped structure; and The area of ​​the end portion of the upper air blowing transition seat connected to the pull rod is smaller than the area of ​​the end surface of the upper air blowing transition seat abutting against the piston; A detection switch for detecting the distance from the outer side wall of the upper air blowing transition seat is also provided on the side wall of the cylinder.

[0015] In an optional implementation of the present invention, the rotor includes an outer shell and a rotor core disposed in the outer shell; wherein Both shaft side ends of the outer shell are annular closed ends fixedly connected to the core shaft, and at least one oil filling port is provided at the annular closed end of one of the shaft side ends.

[0016] In an optional implementation of the present invention, a lower bearing assembly is also connected between the end of the core shaft away from the oil cylinder and the sleeve; The lower bearing assembly comprises a lower bearing seat and a lower bearing body used in conjunction with each other; wherein An annular cooling water jacket is connected in the lower bearing seat, and an annular cavity for containing cooling water is formed between the cooling water jacket and the lower bearing seat.

[0017] The numerical control machining center of the present invention is realized in this way: A numerical control machining center comprises: the universal spindle.

[0018] By adopting the above technical scheme, the present invention has the following beneficial effects: for the universal spindle of the present invention and the CNC machining center using the same, the air inlet group and the oil inlet group arranged on the cylinder head are arranged on two different end faces of the cylinder head, so that the entire spindle can be arranged not only vertically but also horizontally during use, so that it is not only suitable for three-axis machining centers but also for five-axis machining centers, thereby improving the versatility of the spindle for three-axis machining centers and five-axis machining centers.

[0019] Furthermore, by forming air passages suitable for gas circulation between the upper air blowing transition seat, the outer wall of the pull rod and the inner cavity wall of the core shaft, and between the lower air blowing transition seat, a separate air passage suitable for ventilation is constructed inside the main shaft, which can be distinguished from the channel for liquid passage, thereby meeting the use requirements of ventilation and liquid passage at the same time without interfering with each other, and is flexible and reliable to use. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a schematic diagram of the overall structure of the universal main shaft of the present invention; Figure 2 This is a schematic diagram of the local structure of the universal spindle of the present invention. Figure 1 ; Figure 3 This is a schematic diagram of the local structure of the universal spindle of the present invention. Figure 2 ; Figure 4 This is a schematic diagram of the local structure of the universal spindle of the present invention. Figure 3 ; Figure 5 This is a schematic diagram of the local structure of the universal spindle of the present invention. Figure 4 ; Figure 6 This is a schematic diagram of the local structure of the universal spindle of the present invention. Figure 5 ; Figure 7 This is a schematic diagram of the local structure of the universal spindle of the present invention. Figure 6 ; Figure 8 It is a schematic structural diagram of the rotor of the universal main shaft of the present invention; Fig. 9 It is a structural schematic diagram of an air inlet group and an oil inlet group of a cylinder cover of a universal main shaft of the present invention; Fig.10 It is a schematic structural diagram of a pull rod of a universal main shaft of the present invention; Fig.11 It is a structural schematic diagram of the piston of the universal main shaft of the present invention; Fig.12 It is a schematic structural diagram of a cylinder cover of a universal main shaft of the present invention.

[0021] In the figure: sleeve 1, stator 2, rotor 3, outer shell 31, annular closed end 32, oil filling port 33, mandrel 4, tool handle taper hole 41, exhaust channel 42, pull rod 5, hollow liquid channel 51, air channel 52, cylinder 6, proximity switch 61, detection switch 62, air flow channel 63, air storage cavity 64, cylinder head 7, first air inlet 71, second air inlet 72, first oil inlet 73, second oil inlet 74, columnar extension 76, annular base portion 75, gas Body flow channel 77, drainage chamber 78, piston 8, columnar portion 81, annular portion 82, indicator 83, central through hole 85, code disc mounting seat 91, encoder code disc 92, upper air blowing transition seat 10, elastic support 110, lower bearing seat 121, lower bearing body 122, cooling water jacket 123, annular cavity 124, lower air blowing transition seat 130, spring support 140, support ring 141, connecting pipe 150, joint 151, upper bearing assembly 160. DETAILED DESCRIPTION

[0022] In order to make the contents of the present invention more clearly understood, the present invention is further described in detail below based on specific embodiments in conjunction with the accompanying drawings.

[0023] Embodiment 1: See also Figures 1 to 12 As shown, this embodiment provides a universal main shaft, including: a sleeve 1 and a stator 2 arranged in the sleeve 1, a rotor 3 arranged in the stator 2, a core shaft 4 with a hollow cavity which is penetrated in the rotor 3, and a pull rod 5 matched with the hollow cavity of the core shaft 4; wherein the axial length of the core shaft 4 is greater than that of the rotor 3, so that the two axial side ends of the core shaft 4 extend out of the outside of the rotor 3 respectively, and a reliable connection is formed between the core shaft 4 and the rotor 3, so that the rotor 3 can drive the core shaft 4 to rotate.

[0024] Based on the above situation, in order to make the core shaft 4 rotate relative to the sleeve 1, an upper bearing assembly 160 and a lower bearing assembly are respectively arranged between the two ends of the core shaft 4 and the sleeve 1. A cylinder assembly is arranged at one axial side end of the core shaft 4, and the cylinder assembly includes a cylinder barrel 6 connected to the sleeve 1, a cylinder cover 7 connected to the end of the cylinder barrel 6 away from the sleeve 1, and a piston 8 arranged in the cylinder barrel 6. In this regard, the upper bearing assembly 160 is arranged at the end of the core shaft 4 facing the cylinder assembly, and the lower bearing assembly is arranged at the end of the core shaft 4 away from the cylinder.

[0025] Based on the above structure, it is necessary to supplement that the upper bearing assembly 160 in this embodiment is connected to the core shaft 4 through a code disc mounting seat 91, and an encoder code disc 92 is arranged on the code disc mounting seat 91. This design is different from the traditional rear-end nut design. The code disc mounting seat 91 and the core shaft 4 can achieve precise positioning of the inner and outer holes, so that the installation accuracy of the encoder code disc 92 is higher.

[0026] Regarding the universal spindle of this embodiment, it should be noted that a cutter head assembly is also installed at the end of the mandrel 4 away from the oil cylinder. The cutter head assembly here can be any mature means in the prior art, and this embodiment does not make an absolute limitation on its specific structure and implementation principle. For the cooperation between the mandrel 4 and the cutter head assembly, a tool handle tapered hole 41 is formed at the end of the mandrel 4 away from the oil cylinder to achieve the purpose of blowing the tapered hole.

[0027] What is to be explained next is that the piston 8 includes a columnar portion 81 suitable for abutting against the upper blowing transition seat 10, and an annular portion 82 connected to one end of the columnar portion 81 facing the cylinder head 7; wherein the annular portion 82 is folded toward the outside of the columnar portion 81; and an elastic support member 110 is provided between the cylinder barrel 6 and the side end of the annular portion 82 facing away from the cylinder head 7.

[0028] On the basis of the above structure, it should be noted that, optionally, an indicator 83 is further provided on the side of the annular portion 82 facing away from the cylinder head 7; a proximity switch 61 for sensing the indicator 83 is provided on the side wall of the cylinder barrel 6. Based on this structure, when the piston 8 is reset and raised to the highest point, the proximity switch 61 cannot sense the indicator 83, and thus outputs different signals, thereby achieving the purpose of detecting whether the piston 8 is reset. At this time, the upper air blowing transition seat 10 is separated from the columnar portion 81 of the piston 8, and the core shaft 4 can rotate, thereby achieving the purpose of protecting the oil cylinder.

[0029] In an optional implementation, the lower bearing assembly includes a lower bearing seat 121 and a lower bearing body 122 for use together; wherein an annular cooling water jacket 123 is connected to the lower bearing seat 121, and an annular cavity 124 for accommodating cooling water is formed between the cooling water jacket 123 and the lower bearing seat 121. Specifically, a sealing ring is provided between the cooling water jacket 123 and the lower bearing seat 121 to ensure that the cooling water in the cooling cavity does not overflow unexpectedly. For the annular cavity 124, a water inlet channel and a water outlet channel for use together with the cooling water jacket 123 are provided inside the lower bearing seat 121, and a cooling water inlet connected to the water inlet channel and a cooling water outlet connected to the water outlet channel are provided in the lower bearing seat 121. Here, the lower bearing seat 121 is designed in accordance with the cooling water jacket 123. The cooling water jacket 123 has a nearly complete water channel in the radial direction. The cooling water enters the water channel of the cooling water jacket 123 from the water inlet channel inside the lower bearing seat 121, circulates once and flows out from the water outlet channel provided in the cooling water jacket 123, so as to achieve the purpose of cooling the lower bearing seat 121 and the lower bearing body 122. In addition, due to the high-speed rotation of the spindle 4, the lower bearing body 122 may generate thermal expansion, so that the gap between the lower bearing body 122 and the inner hole of the lower bearing seat 121 is filled. The cooling water passing through the annular cavity 124 for accommodating cooling water formed between the cooling water jacket 123 and the lower bearing seat 121 maintains a small gap between the outer circle of the lower bearing body 122 and the inner hole of the lower bearing seat 121, and the annular pressure of the cooling water in the annular cavity 124 forms a self-aligning center, thereby increasing the service life of the lower bearing assembly and the precision of the spindle.

[0030] Furthermore, the tie rod 5 in this embodiment is suitable for sliding along the axial direction of the core shaft 4; one end of the tie rod 5 extends into the cylinder 6, and an upper air blowing transition seat 10 suitable for contacting with the piston 8 is provided at the end of the tie rod 5 extending into the cylinder 6, and a lower air blowing transition seat 130 is sleeved on the part of the tie rod 5 away from the cylinder 6; an air passage suitable for gas circulation is formed between the upper air blowing transition seat 10, the outer wall of the tie rod 5 and the inner cavity wall of the core shaft 4, and the lower air blowing transition seat 130. In this regard, in order to meet the use requirements of the air passage, an exhaust passage 42 connected to the air passage is provided in the part of the core shaft 4 away from the oil cylinder.

[0031] When the universal spindle of this embodiment is loosening the tool, the columnar portion 81 of the piston 8 abuts against the upper air blowing transition seat 10, thereby achieving a sealed fit between the piston 8 and the upper air blowing transition seat 10, so that the air blown into the air path inside the cylinder head 7 of the cylinder can smoothly pass through the upper air blowing transition seat 10 and the circuit of the pull rod 5 into the hollow cavity of the core shaft 4. The hollow cavity of the core shaft 4 extends from the upper part of the spindle to the lower part of the spindle, so that the air flows to the lower part of the core shaft 4, thereby entering the internal circuit of the lower air blowing transition seat 130, and then entering the exhaust channel 42 of the core shaft 4 through the circuit, thereby reaching the tapered hole 41 of the tool handle, thereby achieving the purpose of blowing air into the tapered hole 41 of the tool handle.

[0032] Based on the above situation, in an optional implementation, the upper air blowing transition seat 10 is a frustum-shaped structure; and the area of ​​the end of the upper air blowing transition seat 10 connected to the pull rod 5 is smaller than the area of ​​the end face of the upper air blowing transition seat 10 abutting against the piston 8; a detection switch 62 for detecting the distance from the outer wall of the upper air blowing transition seat 10 is also provided on the side wall of the cylinder 6. The pull rod 5 moves axially to switch between the loose and broaching states. When the spindle is in different states of loosening and broaching the tool, when the pull rod 5 is at different height positions, the upper air blowing transition seat 10 connected thereto is also at different height positions in the spindle. Since its outer surface is a conical surface, the distance from the outer wall of the upper air blowing transition seat 10 that can be detected by the detection switch 62 is different due to the movement of the pull rod 5, thereby outputting different signals, thereby judging whether the spindle is in the state of loosening the tool, broaching the tool or without the tool according to the different output signals of the detection switch 62, which helps to achieve accurate processing and operation.

[0033] A spring support 40 is provided between the outer wall of the pull rod 5 and the inner wall of the core shaft 4; and a plurality of support rings are provided between the outer wall of the pull rod 5 and the inner wall of the core shaft 4 and are arranged at intervals along the axial direction of the rotor 3; each support ring is provided with a through hole which passes through the axial direction of the rotor 3 and is suitable for airflow to pass through.

[0034] The cylinder head 7 is provided with an air inlet group for ventilating air into the cylinder barrel 6 and an oil inlet group for ventilating oil into the cylinder barrel 6; the air inlet group includes a first air inlet 71 and a first oil inlet 73 provided on the end face of the cylinder head 7 along the axial direction of the rotor 3, and the oil inlet group includes a second air inlet 72 and a second oil inlet 74 provided on the side wall of the cylinder head 7 perpendicular to the axial direction of the rotor 3.

[0035] It should be explained in detail that the cylinder head 7 includes a columnar extension 76 for extending into the columnar portion 81 of the piston 8 and an annular base portion 75 connected to one side end of the columnar extension 76 in an outward-turned shape. The annular base portion 75 is suitable for cooperating with the annular portion 82 of the piston 8 and the inner side wall of the cylinder 6 to form a receiving cavity for the oil body entering through the first oil inlet 73 or the second oil inlet 74, that is, the oil body entering the cylinder 6 will not enter the columnar portion 81 of the piston 8. A sealing ring is provided between the outer side wall of the columnar extension 76 and the inner side wall of the columnar portion 81 to prevent the oil body from leaking into the side of the upper air blowing transition seat 10. The joint 151 and the columnar extension 76 are also sealed by a sealing ring to prevent the liquid from leaking into the side of the upper air blowing transition seat 10.

[0036] The first air inlet 71 and the first oil inlet 73 as well as the second air inlet 72 and the second oil inlet 74 are all arranged on the annular base portion 75, and a gas flow channel 77 is provided between the columnar extension portion 76 and the annular base portion 75, which is connected to the first air inlet 71 and the second air inlet 72. In order to cooperate with the gas flow channel 77 here, the end of the columnar portion 81 of the piston 8 facing the upper air blowing transition seat 10 is provided with a central through hole 85 suitable for the connecting pipe 150 to pass through, and the gas flowing in the gas flow channel 77 also enters the upper air blowing transition seat 10 through the central through hole 85.

[0037] Therefore, in this embodiment, the columnar extension portion 76 of the cylinder head 7 is designed to fit in with the columnar portion 81 of the piston 8, so that the cylinder head 7 can meet the requirements of liquid and air circulation without affecting the normal use of the oil cylinder, and three different working chambers for liquid, oil and air circulation are formed in the cylinder barrel 6, which do not interfere with each other and are sealed with each other.

[0038] For the oil cylinder of this embodiment, it is only necessary to introduce and discharge oil on the side of the piston 8 facing away from the rotor 3. When oil is introduced to the side of the piston 8 facing away from the rotor 3 through the first oil inlet 73 or the second oil inlet 74, the piston 8 moves toward the side of the rotor 3, and the elastic support 110, such as a plurality of spring members spaced apart along the circumferential direction, will be compressed and deformed, so that the columnar portion 81 of the piston 8 can abut against the upper air blowing transition seat 10 to form a thrust force on the pull rod 5, thereby realizing the axial movement of the pull rod 5 in the core shaft 4, and the spring support 140 will be compressed and deformed. When the pull rod 5 needs to be reset, under the restoring action of the elastic support 110, the oil on one side of the piston 8 will discharge the oil through the first oil inlet 73 or the second oil inlet 74, and the piston 8 will also release the thrust force on the pull rod 5, so that the pull rod 5 is reset under the restoring action of the spring support 140. By adopting the oil cylinder of the above structure, the space inside the cylinder 6 on the side of the piston 8 facing the rotor 3 can form a space for accommodating the upper blowing transition seat 10, thereby facilitating the smooth use of the airway without interfering with the oil body of the oil cylinder.

[0039] Based on the above oil cylinder, it should be noted that in order to prevent the elastic support member 110 from being fatigued during long-term use of the universal spindle of this embodiment, resulting in a decrease in elastic reliability and failure to ensure the stability of the piston 8, this embodiment also has the following design: An air flow channel 63 for ventilating the cylinder 6 is also provided on the side wall of the cylinder 6 corresponding to the annular portion 82 of the piston 8 facing away from the annular base portion 75. The air flow channel 63 connects the cylinder 6 and the air storage cavity 64 (the air storage cavity 64 is also a cavity for accommodating the elastic support member 110) formed on the side of the annular portion 82 of the piston 8 facing away from the annular base portion 75, so that when the piston 8 moves toward the cylinder head 7, gas is introduced into the above-mentioned air storage cavity 64 through the air flow channel 63 to cooperate with the elastic support member 110, thereby improving the smoothness of the movement of the piston 8 toward the cylinder head 7; and when the piston 8 is to move toward the pull rod 5, the gas in the air storage cavity 64 is discharged to the outside of the cylinder 6 through the air flow channel 63, thereby reducing the gas resistance of the piston 8 moving toward the pull rod 5.

[0040] In addition, it should be noted that a hollow liquid passage 51 is provided inside the tie rod 5 and passes through the tie rod 5 along the axial direction of the rotor 3; and a connecting pipe 150 for connecting the hollow liquid passage 51 and for passing liquid is provided inside the upper air blowing transition seat 10; and the cylinder head 7 is also equipped with a joint 151 that partially extends into the cylinder barrel 6 and is connected to the connecting pipe 150. The joint 151 here is used for external piping so that the liquid passes through the joint 151 to enter the connecting pipe 150 and the hollow liquid passage 51 of the tie rod 5, and finally flows to the cutter head assembly.

[0041] Based on the above situation, it is necessary to explain that the end of the pull rod 5 connected to the upper air blowing transition seat 10 is also provided with an axially extending air vent 52 suitable for gas passage, and the air vent 52 is not connected to the hollow liquid channel 51. At this time, if the hollow liquid channel 51 is opened at the axis of the pull rod 5, then the air vent 52 can be understood as being opened at a non-axial position of the pull rod 5.

[0042] As an example of an optional implementation, a drainage cavity 78 for discharging liquid is also preset in the cylinder head 7. The joint 151 penetrates the drainage cavity 78 and is connected to the connecting pipe 150. The drainage cavity 78 forms a sealed cavity through the cooperation of the sealing cover and the cylinder head 7. For this, a first drainage port connected to the drainage cavity 78 is provided on the end face of the cylinder head 7 along the axial direction of the rotor 3, and a second drainage port connected to the drainage cavity 78 is provided on the side wall of the cylinder head 7 perpendicular to the axial direction of the rotor 3. The drainage cavity 78 and the first drainage port and the second drainage port are designed mainly to discharge the liquid that may flow into the cylinder head 7 when the joint 151 cooperates with the cylinder head 7.

[0043] Regarding the rotor 3 used in this embodiment, an optional implementation is given in conjunction with the attached drawings. The rotor 3 includes an outer shell 31 and a rotor 3 iron core disposed in the outer shell 31; wherein both axial ends of the outer shell 31 are annular closed ends 32 fixedly connected to the core shaft 4, and at least one oil filling port 33 is provided at the annular closed end 32 of one of the axial ends. Under this structure, oil pressure of a certain pressure is introduced into the oil filling port 33, so that the inner cavity of the rotor 3 is expanded as a whole, so that it can be well inserted into the core shaft 4. When the rotor 3 is installed at a specified position in the core shaft 4, the oil flow is stopped, the inner cavity of the rotor 3 is reduced, and it is fixed on the outer circle of the core shaft 4 through its own deformation interference, and the inner circle of the rotor 3 and the outer circle of the core shaft 4 are provided with a taper, so that the two can be well self-centering in the axial direction.

[0044] In summary, for the universal spindle of the present embodiment, the air inlet group and the oil inlet group provided on the cylinder head 7 are both provided on two different end faces of the cylinder head 7, and a first liquid discharge port and a second liquid discharge port are provided correspondingly. In this way, the entire spindle can be arranged not only vertically but also horizontally during use, so that it is not only suitable for three-axis machining centers but also for five-axis machining centers, thereby improving the versatility of the spindle for three-axis machining centers and five-axis machining centers.

[0045] Furthermore, by forming an air passage suitable for gas circulation between the upper air blowing transition seat 10, the outer wall of the pull rod 5 and the inner cavity wall of the core shaft 4, and between the lower air blowing transition seat 130, a separate air passage suitable for ventilation is constructed inside the main shaft, so that it can be distinguished from the channel for liquid passage, thereby meeting the use requirements of ventilation and liquid passage at the same time without interfering with each other, and is flexible and reliable to use.

[0046] Embodiment 2: Based on the universal spindle of Example 1, this embodiment provides a CNC machining center, including: the universal spindle of Example 1. The CNC machining center of this embodiment can be, for example, but not limited to, a three-axis machining center and / or a five-axis machining center. This embodiment does not make an absolute limitation on the specific CNC machining center of this embodiment.

[0047] The above specific embodiments further illustrate the purpose, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above are only specific embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

[0048] In the description of the present invention, it is necessary to understand that the terms indicating orientation or positional relationship are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0049] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0050] In the present invention, unless otherwise clearly specified and limited, a first feature being above or below a second feature may include the first and second features being in direct contact, or may include the first and second features not being in direct contact but being in contact through another feature between them. Moreover, a first feature being above, above, and above a second feature includes the first feature being directly above and obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being below, below, and below a second feature includes the first feature being directly below and obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

Claims

1. A universal spindle, characterized in that: include: A sleeve and a stator arranged in the sleeve, a rotor arranged in the stator, a core shaft with a hollow cavity arranged through the rotor, and a pull rod matched with the hollow cavity of the core shaft; wherein A cylinder assembly is provided at one axial side end of the core shaft, and the cylinder assembly includes a cylinder barrel connected to the sleeve, a cylinder cover connected to one end of the cylinder barrel away from the sleeve, and a piston arranged in the cylinder barrel; The pull rod is suitable for sliding along the axial direction of the core shaft; one end of the pull rod extends into the cylinder, and an upper air blowing transition seat suitable for abutting against the piston is provided at the end of the pull rod extending into the cylinder, and a lower air blowing transition seat is sleeved on the part of the pull rod away from the cylinder; an air channel suitable for gas circulation is formed between the upper air blowing transition seat, the outer wall of the pull rod and the inner cavity wall of the core shaft, and between the lower air blowing transition seat; and The cylinder head is provided with an air inlet group for ventilating air into the cylinder barrel and an oil inlet group for ventilating oil into the cylinder barrel; the piston is provided with a central through hole connecting the air inlet group and the air passage; the air inlet group includes a first air inlet and a first oil inlet provided on the end face of the cylinder head along the axial direction of the rotor, and the oil inlet group includes a second air inlet and a second oil inlet provided on the side wall of the cylinder head perpendicular to the axial direction of the rotor.

2. The universal spindle according to claim 1, characterized in that: An exhaust passage connected with the air passage is arranged in the part of the core shaft away from the oil cylinder.

3. The universal spindle according to claim 1 or 2, characterized in that: A hollow liquid channel is provided inside the pull rod and penetrates the pull rod along the axial direction of the rotor; and The upper air blowing transition seat is provided with a connecting pipe for connecting the hollow liquid channel and for passing liquid; The cylinder cover is also equipped with a joint which partially extends into the cylinder barrel and is used for connecting with a connecting pipe.

4. The universal spindle according to claim 1, characterized in that: A spring support is provided between the outer wall of the pull rod and the inner wall of the core shaft; and A plurality of support rings are also provided between the outer wall of the pull rod and the inner wall of the core shaft and are spaced apart along the axial direction of the rotor; Each supporting ring is provided with a through hole penetrating along the axial direction of the rotor and suitable for air flow to pass through.

5. The universal spindle according to claim 1, characterized in that: The piston comprises a columnar portion adapted to abut against an upper air blowing transition seat, and an annular portion connected to one end of the columnar portion facing the cylinder head; wherein The annular portion is folded toward the outside of the columnar portion; An elastic supporting member is arranged between the cylinder barrel and the side end of the annular portion facing away from the cylinder cover.

6. The universal spindle according to claim 5, characterized in that: The side of the annular portion facing away from the cylinder head is also provided with an indicator; A proximity switch for sensing the indicator is arranged on the side wall of the cylinder.

7. The universal spindle according to claim 5, characterized in that: The upper air blowing transition seat is a frustum-shaped structure; and The area of ​​the end portion of the upper air blowing transition seat connected to the pull rod is smaller than the area of ​​the end surface of the upper air blowing transition seat abutting against the piston; A detection switch for detecting the distance from the outer side wall of the upper air blowing transition seat is also provided on the side wall of the cylinder.

8. The universal spindle according to claim 1, characterized in that: The rotor comprises an outer shell and a rotor core arranged in the outer shell; wherein Both shaft side ends of the outer shell are annular closed ends fixedly connected to the core shaft, and at least one oil filling port is provided at the annular closed end of one of the shaft side ends.

9. The universal spindle according to claim 1, characterized in that: A lower bearing assembly is also connected between the end of the core shaft away from the oil cylinder and the sleeve; The lower bearing assembly includes a lower bearing seat and a lower bearing body used in conjunction with each other; wherein An annular cooling water jacket is connected in the lower bearing seat, and an annular cavity for containing cooling water is formed between the cooling water jacket and the lower bearing seat.

10. A CNC machining center, characterized in that: include: A universal spindle as claimed in any one of claims 1 to 9.

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