Main shaft mechanism for numerical control machine tool and gear machining machine tool

Abstract

According to the main shaft mechanism for the numerical control machine tool and the gear machining machine tool, the main shaft is rotationally installed in the tool rest shell, the direct drive motor is contained in the tool rest shell, the stator assembly of the direct drive motor is fixedly connected with the tool rest shell, and the rotor assembly of the direct drive motor is fixedly arranged on the main shaft in a sleeving mode; the direct drive motor is directly connected with the main shaft, so that the drive motor and the main shaft mechanism do not need to be in transmission connection through a gear, a reverse gap does not exist, high transmission efficiency and high transmission precision are achieved, and the high-precision use requirement of the gear machining numerical control machine tool is met. Moreover, the direct drive motor is directly connected with the main shaft, so that the complexity of a power transmission system is greatly reduced, good concentricity of the rotor assembly and the main shaft is ensured, and the rotating stability of the main shaft is improved. In addition, the spindle and the direct-drive motor directly driving the spindle to rotate are arranged in the tool rest shell, so that the spindle mechanism is more compact in structure, and miniaturization design of a spindle machine body is facilitated.

Description

Technical Field

[0001] The utility model belongs to the technical field of machine tool equipment, and in particular relates to a spindle mechanism for a numerically controlled machine tool and a gear processing machine tool. Background Art

[0002] The spindle of a CNC machine tool refers to the axis on the machine tool that drives the workpiece or tool to rotate. The spindle mechanism of a CNC machine tool is usually composed of a spindle, bearings, and transmission parts. At present, the spindle mechanism of a gear processing machine tool is usually connected by a multi-stage gear transmission between the motor and the spindle mechanism. Since the reverse clearance generated by the gear transmission is generally difficult to eliminate, it is not only easy to cause the problem of low transmission efficiency between the motor and the spindle mechanism, but also causes the defect of poor transmission accuracy between the motor and the spindle mechanism. It is difficult to adapt to the high-precision use requirements of gear processing CNC machine tools, and thus cannot meet the stringent requirements of high precision for the gear components of electric vehicles. Utility Model Content

[0003] Based on the above-mentioned problems existing in the prior art, one of the purposes of the embodiments of the utility model is to provide a spindle mechanism for a CNC machine tool, so as to solve the problem that the motor and the spindle mechanism in the prior art are connected through gear transmission, and the reverse clearance in the gear transmission leads to low transmission efficiency and poor transmission accuracy.

[0004] In order to achieve the above-mentioned purpose, the technical solution adopted by the utility model is: to provide a spindle mechanism for a CNC machine tool, comprising:

[0005] The tool holder housing has a columnar mounting cavity inside;

[0006] A spindle, accommodated in the tool holder housing;

[0007] A first bearing assembly, used for rotatably mounting the nose end of the spindle on the tool holder housing;

[0008] A second bearing assembly, used for rotatably mounting the rear end of the spindle on the tool holder housing; and

[0009] A direct drive motor, comprising a stator assembly fixedly arranged inside the tool holder housing and a rotor assembly sleeved on the main shaft, wherein the rotor assembly is located inside the stator assembly, and the rotor assembly and the stator assembly are spaced apart from each other;

[0010] The rotor assembly is fixedly connected to the main shaft, and the central axis of the rotor assembly is colinear with the central axis of the main shaft, so that when the direct drive motor is working, the rotor assembly drives the main shaft to rotate synchronously.

[0011] Furthermore, the first bearing assembly includes at least two first bearing units, and each of the first bearing units includes two first bearings arranged in pairs and side by side.

[0012] Furthermore, the second bearing assembly includes at least one first bearing unit, and each of the first bearing units includes two second bearings arranged in pairs and side by side.

[0013] Furthermore, the spindle mechanism for a CNC machine tool also includes a broaching mechanism for locking a tool to the nose end of the spindle, the spindle is provided with a sliding hole axially therethrough, the broaching mechanism includes a broaching shaft axially slidably arranged in the sliding hole and an elastic member for pushing the broaching shaft toward the broaching position.

[0014] Furthermore, the elastic member is a spring sleeved on the broach shaft, and the broach mechanism also includes a first abutment member slidably sleeved on the broach shaft and fixedly connected to the main shaft, and a second abutment member fixedly sleeved on the broach shaft, the first end of the spring abuts against the first abutment member, and the second end of the spring abuts against the second abutment member.

[0015] Furthermore, the second supporting member is a locking nut, and an external thread adapted to the locking nut is provided at a position on the broach shaft corresponding to the locking nut. The locking nut is screwed onto the broach shaft, and the locking nut is slidably disposed in the sliding hole.

[0016] Furthermore, the spindle mechanism for the CNC machine tool also includes a tool releasing mechanism for pushing the tool pulling shaft toward the tool releasing position, the tool releasing mechanism is arranged on the tool holder housing near the rear end of the spindle, the tool releasing mechanism includes a hydraulic cylinder fixedly connected to the tool holder housing and a tool pushing rod for pushing the tool pulling shaft toward the tool releasing position, and the tool pushing rod is connected to the piston rod of the hydraulic cylinder.

[0017] Furthermore, the spindle mechanism for a numerically controlled machine tool further comprises an inertia mechanism, wherein the inertia mechanism is sleeved on the spindle, and the inertia mechanism is located between the first bearing assembly and the rotor assembly.

[0018] Furthermore, a cooling circulation channel for circulating coolant is provided on the tool holder housing and / or the stator assembly.

[0019] Based on the above problems existing in the prior art, a second purpose of the embodiments of the utility model is to provide a gear processing machine tool having a spindle mechanism for a CNC machine tool in any of the above solutions.

[0020] In order to achieve the above-mentioned purpose, the technical solution adopted by the present invention is: to provide a gear processing machine tool, including the spindle mechanism for CNC machine tools provided by any of the above-mentioned solutions.

[0021] Compared with the prior art, the above one or more technical solutions in the embodiments of the present invention have at least one of the following beneficial effects:

[0022] The spindle mechanism and gear processing machine tool for CNC machine tools in the embodiment of the utility model are installed by rotating the spindle inside the tool holder housing, accommodating the direct drive motor in the tool holder housing, fixing the stator assembly of the direct drive motor to the tool holder housing, and fixing the rotor assembly of the direct drive motor on the spindle, so that the direct drive motor is directly connected to the spindle, so that there is no reverse clearance between the drive motor and the spindle mechanism without the need for gear transmission connection, and has high transmission efficiency and high transmission accuracy, meeting the high-precision use requirements of gear processing CNC machine tools. In addition, the direct drive motor is directly connected to the spindle, which greatly reduces the complexity of the power transmission system, ensures that the rotor assembly and the spindle have good concentricity, and improves the stability of the spindle rotation. In addition, the spindle and the direct drive motor that directly drives the spindle to rotate are arranged in the tool holder housing, so that the entire spindle mechanism structure is more compact, which is conducive to the miniaturization design of the spindle body, saving costs and installation space on the machine tool. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0024] Figure 1 A schematic cross-sectional view of the spindle mechanism for a CNC machine tool provided by the utility model;

[0025] Figure 2 An assembly diagram of the broach mechanism and the spindle provided by the utility model;

[0026] Figure 3 An assembly diagram of the tool holder housing and the tool holder seat provided by the utility model;

[0027] Figure 4 A schematic cross-sectional view of the tool holder housing provided by the utility model;

[0028] Figure 5 A schematic cross-sectional view of the spindle mechanism for a CNC machine tool provided by the utility model;

[0029] Figure 6 for Figure 5 A schematic diagram of the partially enlarged structure;

[0030] Figure 7 for Figure 5 A schematic diagram of the partially enlarged structure;

[0031] Figure 8 An assembly diagram of the second sealing assembly provided by the utility model;

[0032] Fig. 9 A schematic cross-sectional view of the third annular seal provided by the utility model;

[0033] Fig.10 A schematic cross-sectional view of the second locking member provided by the utility model;

[0034] Fig.11 An assembly diagram of the first sealing assembly provided by the utility model;

[0035] Fig.12 A schematic cross-sectional view of the rear end bearing seat provided by the utility model;

[0036] Fig.13 This is a schematic cross-sectional structural diagram of the first locking member provided by the utility model.

[0037] Among them, the reference numerals in the figure are:

[0038] 1-tool holder housing; 11-installation cavity; 12-neck opening; 13-disassembly opening; 14-mouth; 15-dovetail guide rail;

[0039] 2-main axis; 21-nose end; 22-rear end; 23-sliding hole;

[0040] 3-first sealing assembly; 31-rear end bearing seat; 311-first annular groove; 312-sealing reinforcement ring; 313-center annular hole; 32-first annular sealing member; 33-first locking member; 331-inner threaded sleeve; 332-external pressing end cover; 333-inner pressing end cover; 34-sealing gland;

[0041] 4-second sealing assembly; 41-second annular sealing member; 42-third annular sealing member; 421-annular sealing body; 422-annular sealing cover; 423-first step groove; 424-second step groove; 425-third step groove; 43-second locking member; 431-locking nut; 432-holding convex ring;

[0042] 5-direct drive motor; 51-stator assembly; 52-rotor assembly;

[0043] 6- broach mechanism; 61- broach shaft; 611- diameter expansion section; 62- elastic member; 63- first abutting member; 64- second abutting member;

[0044] 7-knife release mechanism; 71-hydraulic cylinder; 72-knife top rod;

[0045] 8- measuring assembly; 81- measuring element; 82- sealing element;

[0046] 9-tool holder seat; 91-dovetail slide;

[0047] 10- inertia mechanism; 20- cooling circulation channel; 30- gas transmission channel;

[0048] 40-first bearing assembly; 401-first bearing;

[0049] 50-second bearing assembly; 501-second bearing;

[0050] 60-wire box assembly; 601-box body; 602-terminal block; 603-outlet seal; 604-outlet hole;

[0051] 70-first sealing ring; 80-sealing groove. DETAILED DESCRIPTION

[0052] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0053] It should be noted that when an element is referred to as being "connected to" or "disposed on" another element, it can be directly on the other element or indirectly on the other element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or indirectly connected to the other element.

[0054] In addition, the terms "first", "second", and "third" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first", "second", and "third" may explicitly or implicitly include one or more of the features. In the description of the present utility model, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0055] In the description of the present invention, it should be understood that the terms "center", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a dedicated orientation, be constructed and operated in a dedicated orientation, and therefore cannot be understood as a limitation on the present invention.

[0056] In the description of the present utility model, it should be noted that, unless otherwise clearly specified and limited, the terms "installation", "connection" and "connection" 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 utility model can be understood according to specific circumstances.

[0057] Reference throughout the specification to "one embodiment" or "an embodiment" means that the specialized features, structures, or characteristics described in connection with the embodiment are included in at least one embodiment of the present application. Thus, the phrases "in one embodiment," "in some embodiments," or "in some of these embodiments" appear in various places throughout the specification, not all of which refer to the same embodiment. Furthermore, in one or more embodiments, the specialized features, structures, or characteristics may be combined in any suitable manner.

[0058] Please also read Figures 1 to 4Now, the spindle mechanism for a CNC machine tool provided by the embodiment of the utility model is described. The spindle mechanism for a CNC machine tool provided by the embodiment of the utility model comprises a tool holder housing 1, a spindle 2, a first bearing assembly 40, a second bearing assembly 50 and a direct drive motor 5. The tool holder housing 1 has a columnar mounting cavity 11 inside, the spindle 2 is accommodated in the tool holder housing 1, the nose end 21 of the spindle 2 and the rear end 22 of the spindle 2 extend out of the tool holder housing 1 respectively, the first bearing assembly 40 rotatably mounts the nose end 21 of the spindle 2 on the tool holder housing 1, and the second bearing assembly 50 rotatably mounts the rear end 22 of the spindle 2 on the tool holder housing 1, thereby realizing the rotatable mounting of the spindle 2 on the tool holder housing 1 and enhancing the stability of the installation of the spindle 2. The direct drive motor 5 is accommodated in the tool holder housing 1, which improves the compactness of the spindle mechanism structure on the one hand, and is conducive to reducing the volume of the spindle mechanism structure on the other hand. The direct drive motor 5 includes a stator assembly 51 fixedly arranged inside the tool holder housing 1 and a rotor assembly 52 sleeved on the main shaft 2. The rotor assembly 52 is located inside the stator assembly 51, and the rotor assembly 52 is spaced apart from the stator assembly 51. The rotor assembly 52 includes a permanent magnet and a rotor bracket. The rotor bracket is sleeved on the main shaft 2, and the permanent magnet is sleeved on the rotor bracket, and the permanent magnet is fixed on the rotor bracket. The permanent magnet can provide the necessary air gap magnetic field for the direct drive motor 5. The winding on the stator assembly 51 is connected to a three-phase alternating current. After the current is passed, a rotating magnetic field is formed in the winding. Since the permanent magnet is installed on the rotor bracket, the magnetic poles of the permanent magnet are fixed. According to the principle that like poles attract each other and opposite poles repel each other, the rotating magnetic field generated in the stator assembly 51 drives the permanent magnet to rotate. Since the permanent magnet is fixedly connected to the rotor bracket, the rotor bracket is driven to rotate, and the electrical energy is converted into mechanical energy. Among them, the rotor assembly 52 is fixedly connected to the main shaft 2, and the central axis of the rotor assembly 52 is colinear with the central axis of the main shaft 2, so that when the direct drive motor 5 is working, the rotor assembly 52 can directly drive the main shaft 2 to rotate synchronously, which greatly reduces the complexity of the power transmission system, ensures that the rotor assembly 52 and the main shaft 2 have good concentricity, and there is no need for the drive motor and the main shaft mechanism to be connected through gear transmission and there is no reverse clearance, which has high transmission efficiency and high transmission accuracy.

[0059] The spindle mechanism for a CNC machine tool provided by the embodiment of the utility model, compared with the prior art, is to install the spindle 2 in a rotation manner inside the tool holder housing 1, and to accommodate the direct drive motor 5 in the tool holder housing 1, to fix the stator assembly 51 of the direct drive motor 5 to the tool holder housing 1, and to fix the rotor assembly 52 of the direct drive motor 5 on the spindle 2, so that the direct drive motor 5 is directly connected to the spindle 2, so that there is no reverse clearance between the drive motor and the spindle mechanism without the need for gear transmission connection, and has high transmission efficiency and high transmission accuracy, meeting the high-precision use requirements of gear processing CNC machine tools. In addition, the direct drive motor 5 is directly connected to the spindle 2, which greatly reduces the complexity of the power transmission system, ensures that the rotor assembly 52 has good concentricity with the spindle 2, and improves the stability of the rotation of the spindle 2. In addition, the spindle 2 and the direct drive motor 5 that directly drives the spindle 2 to rotate are arranged in the tool holder housing 1, so that the entire spindle mechanism structure is more compact, which is conducive to the miniaturization design of the spindle 2 body, saving costs and installation space on the machine tool.

[0060] Please refer to Figure 1 and Figure 2 In some embodiments, the first bearing assembly 40 includes at least two first bearing units, each of which includes two first bearings 401 arranged in pairs and side by side, so that the main shaft 2 has the characteristics of high speed and high rigidity when rotating.

[0061] Please refer to Figure 1 and Figure 2 In some of the embodiments, the second bearing assembly 50 includes at least one second bearing unit, and each second bearing unit includes two second bearings 501 arranged in pairs and side by side, so that the main shaft 2 has the characteristics of high speed and high rigidity when rotating.

[0062] Please refer to Figure 1 and Figure 2 In some embodiments, the spindle mechanism for a CNC machine tool further includes a broaching mechanism 6 for locking a tool at the nose end 21 of the spindle 2. The spindle 2 is provided with a sliding hole 23 extending therethrough in the axial direction. The broaching mechanism 6 includes a broaching shaft 61 slidably disposed in the sliding hole 23 in the axial direction and an elastic member 62 for pushing the broaching shaft 61 toward the broaching position. In this embodiment, since the broaching shaft 61 is slidably disposed in the sliding hole 23 of the spindle 2, the broaching shaft 61 can be pushed to the broaching position by only utilizing the restoring force of the elastic member 62 when compressed, thereby realizing the broaching function of the broaching mechanism 6. In addition, the broaching shaft 61 has an air supply channel 30 extending therethrough in the axial direction, and the blowing device can blow air to the spindle 2 through the air supply channel 30 to blow away the iron filings that fall on the spindle 2, thereby preventing the iron filings from accumulating at the nose end 21 of the spindle 2 and affecting the installation and removal of the tool.

[0063] Please refer to Figure 1 and Figure 2 In some embodiments, the elastic member 62 is a spring sleeved on the broach shaft 61, and the broach mechanism 6 also includes a first abutting member 63 slidably sleeved on the broach shaft 61 and fixedly connected to the main shaft 2, and a second abutting member 64 fixedly sleeved on the broach shaft 61, the first end of the spring abuts against the first abutting member 63, and the second end of the spring abuts against the second abutting member 64. In this embodiment, since the broach shaft 61 is slidably set in the sliding hole 23 of the main shaft 2, the elastic member 62 is a spring sleeved on the broach shaft 61, and the broach shaft 61 can be pushed to the broaching position by only utilizing the restoring force of the spring when it is compressed, thereby realizing the broaching function of the broach mechanism 6. In addition, sleeved on the broach shaft 61, it is beneficial to prevent radial runout from occurring during compression and affecting the sliding stability of the broach shaft 61.

[0064] Please refer to Figure 1 and Figure 2 In some embodiments, in order to facilitate the installation of the spring and reduce the friction between the broaching shaft 61 and the sliding hole 23, the second abutting member 64 is a locking nut, and the position of the broaching shaft 61 corresponding to the locking nut is provided with an external thread adapted to the locking nut, the locking nut is screwed on the broaching shaft 61, and the locking nut is slidably disposed in the sliding hole 23. Further, in order to reduce the friction between the broaching shaft 61 and the sliding hole 23, an expanded diameter section 611 is provided at one end of the broaching shaft 61 away from the locking nut, and the expanded diameter section 611 is slidably disposed in the sliding hole 23, and a gap is formed between the portion of the broaching shaft 61 located between the expanded diameter section 611 and the locking nut and the sliding hole 23.

[0065] Please refer to Figure 1 and Figure 2 In some embodiments, the spindle mechanism for the CNC machine tool further includes a tool release mechanism 7 for pushing the broaching shaft 61 toward the tool release position. The tool release mechanism 7 is disposed on the tool holder housing 1 at a position adjacent to the rear end 22 of the spindle 2. The tool release mechanism 7 includes a hydraulic cylinder 71 fixedly connected to the tool holder housing 1 and a tool push rod 72 for pushing the broaching shaft 61 toward the tool release position. The tool push rod 72 is connected to the piston rod of the hydraulic cylinder 71. In this embodiment, the tool push rod 72 is driven by the hydraulic cylinder 71, and the tool push rod 72 pushes the broaching shaft 61 toward the tool release position. During the movement of the broaching shaft 61, the locking nut compresses the spring, so that the broaching shaft 61 can be pushed to the tool release position, thereby realizing the tool broaching function of the tool release mechanism 7. When the hydraulic cylinder 71 is depressurized and stops driving the tool push rod 72, the broaching shaft 61 can be pushed to the tool release position by only utilizing the restoring force of the spring when it is compressed, thereby realizing the tool broaching function of the automatic tool broaching mechanism 6.

[0066] Please refer to Figure 1 and Figure 2In some of the embodiments, the spindle mechanism for the CNC machine tool also includes an inertia mechanism 10, which is sleeved on the spindle 2. The inertia mechanism 10 is located between the first bearing assembly 40 and the rotor assembly 52, which can not only increase the inertia of the spindle 2 during operation, but also reduce the inertia impact when the spindle 2 starts and stops.

[0067] Please refer to Figure 1 and Figure 2 In some of the embodiments, a cooling loop 20 for circulating coolant is provided on the tool holder housing 1 and / or the stator assembly 51, which is beneficial for cooling the tool holder housing 1 and / or the drive motor by the coolant, thereby avoiding overheating of the spindle 2.

[0068] Please refer to Figure 1 and Figure 2 In some embodiments, in order to monitor the rotation performance of the spindle 2 in real time, a measuring assembly 8 for measuring various performance parameters of the spindle 2 is provided at a position on the tool holder housing 1 corresponding to the rear end 22 of the spindle 2, and the measuring assembly 8 includes a measuring element 81 provided on the first locking member 33 and a sealing member 82 for sealing the measuring assembly 8. It should be noted that the first locking member 33 of the first sealing member 3 is connected to the tool holder housing 1 and / or the spindle 2, and the first locking member 33 may be, but is not limited to, a connecting seat that can connect the measuring element 81 to the tool holder housing 1 and / or the spindle 2.

[0069] Please refer to Figure 3 In some of the embodiments, the spindle mechanism for the CNC machine tool also includes a tool holder seat 9 supporting the tool holder housing 1. In order to enable the spindle 2 to drive the tool to move axially along the spindle 2 and facilitate the tool shifting operation, a dovetail guide rail 15 is provided on the tool holder housing 1, and a dovetail groove 91 that slides with the dovetail guide rail 15 is provided on the tool holder seat 9.

[0070] Please refer to Figure 5 , Figure 6 and Fig.11 The spindle mechanism for a CNC machine tool provided by the embodiment of the utility model also includes a first sealing assembly 3. The front end of the tool holder housing 1 has a necking opening 12 connected to the installation cavity 11, and the rear end 22 of the tool holder housing 1 has a disassembly opening 13 connected to the installation cavity 11. The nose end 21 of the spindle 2 and the rear end 22 of the spindle 2 extend to the outside of the tool holder housing 1 from the necking opening 12 and the disassembly opening 13 respectively. The first bearing assembly 40 rotatably installs the nose end 21 of the spindle 2 in the necking opening 12, and the second bearing assembly 50 rotatably installs the rear end 22 of the spindle 2 in the disassembly opening 13, thereby realizing the rotatable installation of the spindle 2 on the tool holder housing 1 and enhancing the stability of the installation of the spindle 2. Please refer to further reference. Figure 2 , Figure 5 and Figure 6The first sealing assembly 3 includes a rear end bearing seat 31 rotatably sleeved on the rear end 22 of the main shaft 2, a first annular seal 32 for pressing and sealing the second bearing assembly 50 in the annular sealing cavity of the rear end bearing seat 31, and a first locking member 33 for locking the first annular seal 32 on the rear end bearing seat 31, a sealing gland 34 for closing the disassembly opening 13 and limiting the rear end bearing seat 31 in the disassembly opening 13, and a bolt for detachably mounting the sealing gland 34 on the tool holder housing 1, and the outer peripheral wall of the rear end bearing seat 31 is tightly fitted with the inner side wall of the disassembly opening 13 to prevent the second bearing assembly 50 from being pressed against the annular sealing cavity of the rear end bearing seat 31. The disassembly and assembly port 13 of the tool holder housing 1 has a sealing effect, and the rear end 22 of the spindle 2 is detachably connected to the first locking piece 33 by screws. The first annular seal 32 is in sliding sealing contact with the rear end bearing seat 31 and / or the first locking piece 33 and / or the rear end 22 of the spindle 2. Not only is the structure simple and compact, but it can also achieve sealing of the rear end 22 of the spindle 2 without affecting the high-speed rotation of the spindle 2 driven by the direct drive motor 5, preventing oil from leaking into the tool holder housing 1 and causing oil to corrode the direct drive motor 5, causing the direct drive motor 5 to be short-circuited and damaged, thereby affecting the normal operation of the direct drive motor 5. When the built-in direct-drive motor 5 fails and needs to be repaired, it is only necessary to remove the sealing gland 34 from the disassembly port 13 of the tool holder housing 1, and then the second bearing assembly 50, the first locking member 33 and the first annular seal 32 can be removed together with the rear end bearing seat 31, so that the sealing structure formed by the first sealing assembly 3 can be quickly disassembled in a timely and convenient manner, and the direct-drive motor 5 can be taken out from the inside of the tool holder housing 1 for repair, which is conducive to improving the repair efficiency. After the direct-drive motor 5 is repaired, it is only necessary to connect the sealing gland 34 to the disassembly port 13 of the tool holder housing 1 by bolts, so that the second bearing assembly 50, the first locking member 33 and the first annular seal 32 together with the rear end bearing seat 31 can be confined in the disassembly port 13 of the tool holder housing 1, so that the sealing structure formed by the first sealing assembly 3 can be quickly installed in a timely and convenient manner.

[0071] Please refer to Figure 5 , Figure 6 and Figure 7In some embodiments, the spindle mechanism for a CNC machine tool further includes a second sealing assembly 4 for sealing the nose end 21 of the spindle 2, the second sealing assembly 4 includes a second annular seal 41 and a third annular seal 42 for pressing and sealing the first bearing assembly 40 in the necking opening 12, the second annular seal 41 is arranged at the connection between the necking opening 12 and the mounting cavity 11, the second annular seal 41 is clamped and fixed between the stator assembly 51 and the inner side wall of the tool holder housing 1, the third annular seal 42 is arranged at the mouth 14 of the necking opening 12, the second sealing assembly 4 further includes a second locking piece 43 for locking the third annular seal 42 to the nose end 21 of the spindle 2, and the nose end 21 of the spindle 2 is threadedly connected to the second locking piece 43. When the spindle 2 is worn and / or the direct drive motor 5 fails, the spindle 2 and the direct drive motor 5 sleeved on the spindle 2 can be pulled out from the disassembly opening 13 of the tool holder housing 1 by only removing the second locking member 43 from the nose end 21 of the spindle 2, thereby facilitating the replacement of the spindle 2 and / or the maintenance of the direct drive motor 5. In addition, in order to improve the sealing performance, a sealing groove 80 is provided on the second annular sealing member 41, and a second sealing ring is provided in the sealing groove 80.

[0072] Please refer to Figure 7 , Figure 8 , Fig. 9 and Fig.10 In some embodiments, the second locking member 43 is a locking nut 431, and the nose end 21 of the main shaft 2 is provided with an external thread that matches the internal thread of the locking nut 431. The second locking member 43 includes a locking nut 431 and a supporting protrusion 432 extending radially outward from one end of the locking nut 431. A first step groove 423 for the supporting protrusion 432 to abut is provided on the corresponding end surface of the third annular seal 42. The supporting protrusion 432 is accommodated in the first step groove 423 and contacts the third annular seal 42 in a liquid-tight manner. The first step groove 423 is provided on the end surface of the annular sealing cover 422 facing the supporting protrusion 432. A second step groove 424 is provided on the annular sealing cover 422 at a position adjacent to the first step groove 423. A first sealing ring 70 is provided in the second step groove 424. The locking nut 431 is inserted into the second step groove 424 to press the first sealing ring 70 against the second step groove 424, so as to form a labyrinth seal structure and improve the sealing effect. Furthermore, a third step groove 425 is provided on the annular sealing cover 422 near the second step groove 424, and the end of the locking nut 431 away from the supporting convex ring 432 is inserted into the third step groove 425, which can form a labyrinth seal structure and improve the sealing effect. It should be noted that the first step groove 423, the second step groove 424 and the third step groove 425 are all annular step grooves, and the second step groove 424 connects the first step groove 423 and the third step groove 425, which can form a labyrinth seal groove structure with good sealing performance.

[0073] Please refer to Figure 3 , Figure 4 , Figure 5 and Figure 6 In some embodiments, the third annular seal 42 includes an annular sealing body 421 for inserting into the necking opening 12 to press against the first bearing assembly 40 and an annular sealing cover 422 extending radially outward from one end of the annular sealing cover 422. The annular sealing cover 422 is covered on the mouth 14 of the necking opening 12 and is in liquid-tight contact with the necking opening 12, so as to form a labyrinth sealing structure and improve the sealing effect.

[0074] Please refer to Figure 6 , Fig.11 , Fig.12 and Fig.13 In some embodiments, the first end surface of the rear end bearing seat 31 is provided with a first annular groove 311 for accommodating and positioning the first annular seal 32, the outer peripheral surface of the first annular seal 32 is in liquid-tight contact with the inner surface of the first annular groove 311, and the first locking member 33 includes an internal threaded sleeve 331 sleeved on the rear end 22 of the main shaft 2 and an external pressing end cover 332 extending radially outward from the first end of the internal threaded sleeve 331, the second end of the internal threaded sleeve 331 is inserted into the first annular groove 311, and the external pressing end cover 332 is covered on the notch of the first annular groove 311 to press and seal the first annular seal 32 in the first annular groove 311. In addition, an inner pressing end cover 333 for cooperating with and resisting the rear end 22 of the main shaft 2 is provided in the internal threaded sleeve 331. The inner pressing end cover 333 is in liquid-tight contact with the rear end 22 of the main shaft 2. The second end of the rear end bearing seat 31 extends radially inward and is provided with a sealing reinforcement ring 312 for being sleeved on the rear end 22 of the main shaft 2. The sealing reinforcement ring 312, the center annular hole 313 of the rear end bearing seat 31, the first annular seal 32 and the rear end 22 of the main shaft 2 form a closed annular sealing cavity, and the second bearing assembly 50 is accommodated in the annular sealing cavity.

[0075] Please refer to Figure 1 and Figure 3 In some embodiments, the spindle mechanism for a CNC machine tool further includes a wire box assembly 60 disposed on the tool holder housing 1, the wire box assembly 60 including a box body 601, a terminal block 602 disposed inside the box body 601, a wire electrically connected to the terminal block 602, and an outlet seal 603 and / or an inlet seal disposed in an outlet hole 604 and / or an inlet hole. The outlet hole 604 and / or the inlet hole are sealed by the outlet seal 603 and / or the inlet seal, which can prevent oil and water from entering the box body 601 and causing short circuit damage to electrical components. Specifically, the box body 601 is disposed on the sealing gland 34, and when the sealing gland 34 closes the disassembly and assembly port 13 on the tool holder housing 1, the box body 601 can be installed on the tool holder housing 1 through the sealing gland 34.

[0076] The embodiment of the utility model also provides a gear processing machine tool, which includes the spindle mechanism for a CNC machine tool provided in any of the above embodiments. Since the gear processing machine tool has all the technical features of the spindle mechanism for a CNC machine tool provided in any of the above embodiments, it has the same technical effects as the spindle mechanism for a CNC machine tool.

[0077] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A spindle mechanism for a CNC machine tool, characterized in that: include: The tool holder housing has a columnar mounting cavity inside; A spindle, accommodated in the tool holder housing; A first bearing assembly, used for rotatably mounting the nose end of the spindle on the tool holder housing; A second bearing assembly, used for rotatably mounting the rear end of the spindle on the tool holder housing; as well as A direct drive motor, comprising a stator assembly fixedly arranged inside the tool holder housing and a rotor assembly sleeved on the main shaft, wherein the rotor assembly is located inside the stator assembly, and the rotor assembly and the stator assembly are spaced apart from each other; The rotor assembly is fixedly connected to the main shaft, and the central axis of the rotor assembly is colinear with the central axis of the main shaft, so that when the direct drive motor is working, the rotor assembly drives the main shaft to rotate synchronously.

2. The spindle mechanism for a CNC machine tool according to claim 1, characterized in that: The first bearing assembly includes at least two first bearing units, and each of the first bearing units includes two first bearings arranged in pairs and side by side.

3. The spindle mechanism for a CNC machine tool according to claim 1, characterized in that: The second bearing assembly includes at least one first bearing unit, and each of the first bearing units includes two second bearings arranged in pairs and side by side.

4. The spindle mechanism for a CNC machine tool according to claim 1, characterized in that: The spindle mechanism for a CNC machine tool also includes a broaching mechanism for locking a tool to the nose end of the spindle. The spindle is provided with a sliding hole axially therethrough. The broaching mechanism includes a broaching shaft slidably arranged in the sliding hole axially and an elastic member for pushing the broaching shaft toward the broaching position.

5. The spindle mechanism for a CNC machine tool according to claim 4, characterized in that: The elastic member is a spring sleeved on the broach shaft, and the broach mechanism also includes a first abutment member slidably sleeved on the broach shaft and fixedly connected to the main shaft, and a second abutment member fixedly sleeved on the broach shaft, the first end of the spring abuts against the first abutment member, and the second end of the spring abuts against the second abutment member.

6. The spindle mechanism for a CNC machine tool according to claim 5, characterized in that: The second supporting member is a locking nut, and an external thread matching the locking nut is provided on the broach shaft at a position corresponding to the locking nut. The locking nut is screwed onto the broach shaft, and the locking nut is slidably disposed in the sliding hole.

7. The spindle mechanism for a CNC machine tool according to claim 4, characterized in that: The spindle mechanism for the CNC machine tool also includes a tool releasing mechanism for pushing the tool pulling shaft toward the tool releasing position. The tool releasing mechanism is arranged on the tool holder housing near the rear end of the spindle. The tool releasing mechanism includes a hydraulic cylinder fixedly connected to the tool holder housing and a tool pushing rod for pushing the tool pulling shaft toward the tool releasing position. The tool pushing rod is connected to the piston rod of the hydraulic cylinder.

8. The spindle mechanism for a CNC machine tool according to claim 1, characterized in that: The spindle mechanism for a numerically controlled machine tool further comprises an inertia mechanism, wherein the inertia mechanism is sleeved on the spindle and is located between the first bearing assembly and the rotor assembly.

9. The spindle mechanism for a CNC machine tool according to any one of claims 1 to 8, characterized in that: The tool holder housing and / or the stator assembly is provided with a cooling circulation channel for circulating coolant.

10. A gear processing machine tool, characterized in that: It comprises a spindle mechanism for a numerically controlled machine tool as claimed in any one of claims 1 to 9.

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