CN216263494U - Main shaft device of machine tool - Google Patents
Main shaft device of machine tool Download PDFInfo
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- CN216263494U CN216263494U CN202122084601.3U CN202122084601U CN216263494U CN 216263494 U CN216263494 U CN 216263494U CN 202122084601 U CN202122084601 U CN 202122084601U CN 216263494 U CN216263494 U CN 216263494U
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- machine tool
- rotating shaft
- sleeve
- rotor
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Abstract
The utility model relates to the technical field of machining, and particularly discloses a main shaft device of a machine tool, which comprises a shell, a rotating shaft, a rotor and a stator, wherein the front end of the rotating shaft is provided with an inner hole conical surface, the inner hole conical surface is provided with an annular groove, and the annular groove is positioned in the middle of the inner hole conical surface; the rotor is provided with a permanent magnet section and a non-permanent magnet section, the permanent magnet section is provided with a winding, the non-permanent magnet section is detachably connected to the rotating shaft, and the rotor is in clearance fit with the rotating shaft. The main shaft device is used for solving the problem that a main shaft is easy to wear or damage in the assembling or using process of the main shaft device in the prior art.
Description
Technical Field
The utility model relates to the technical field of machining, in particular to a spindle device of a machine tool.
Background
The high-speed precision spindle device such as an electric spindle is used as a marking functional part of a modern machine tool, is rapidly developed and perfected in several years, is applied to various machine tools such as turning, milling, grinding and the like at present, is a preferred part in a high-grade machining center, and comprises a shell, a rotating shaft, a rotor, a stator and the like, wherein the rotor is fixedly connected with the rotating shaft, and the stator is fixedly connected with the shell; the inside cavity of pivot, in order to conveniently install broach mechanism, broach mechanism includes driver and pull rod, the driver (like the hydro-cylinder) drives the pull rod at pivot axial displacement, the pull rod is kept away from the front end of driver and is installed handle of a knife mechanism, handle of a knife mechanism is including the connecting block, the connecting block shaping of handle of a knife mechanism has the handle of a knife conical surface, and the pivot front end also shaping have with the conical surface complex of handle of a knife hole conical surface, however because the tool changing needs, once the tool changing, just need take off handle of a knife mechanism from the pivot pine, the tool changing number of times is many, also comparatively frequent mutual laminating and separation can appear with the handle of a knife conical surface, make the easy wearing and tearing of hole conical surface, and then influence the positioning accuracy of pivot, reduce spindle unit's machining precision.
In addition, when the rotor is installed into the pivot, guarantee the installation stability of rotor and pivot and do not destroy the magnetic field on the rotor again, then accomplish fixed connection through the interference fit of rotor and pivot, however this kind of interference fit's mode, when the rotor suit, must heat the rotor to make the rotor extrude into in the pivot under the powerful strike, this kind of assembly methods is consuming time hard, the assembly effect is difficult to guarantee, and still there is the condition of damaging rotor or pivot. In order to reduce the assembly difficulty in the prior art, the rotor is usually bonded on the rotating shaft by adopting a viscose mode, but the viscose mode has the risk of loosening after the rotor rotates for a long time.
SUMMERY OF THE UTILITY MODEL
The utility model aims to provide a spindle device of a machine tool, which aims to solve the problem that a spindle is easy to wear or damage in the process of assembling or using the spindle device in the prior art.
In order to achieve the above object, the basic scheme of the utility model is as follows:
a main shaft device of a machine tool comprises a shell, a rotating shaft, a rotor and a stator, wherein the front end of the rotating shaft is provided with an inner hole conical surface, the inner hole conical surface is provided with an annular groove, and the annular groove is positioned in the middle of the inner hole conical surface; the rotor is provided with a permanent magnet section and a non-permanent magnet section, the permanent magnet section is provided with a winding, the non-permanent magnet section is detachably connected to the rotating shaft, and the rotor is in clearance fit with the rotating shaft.
Compare the beneficial effect in prior art: when this scheme of adoption, the permanent magnetism section of rotor is used for producing the magnetic field, utilizes dismantling of non-permanent magnetism section and pivot to be connected, in addition the clearance fit of rotor and pivot for the process of installation rotor becomes simple quick, has avoided the problem of the pivot damage that external force knocked and caused in the assembling process.
In addition, the annular groove is formed in the inner hole conical surface of the rotating shaft, so that the contact area between the inner hole conical surface and the cutter handle conical surface is reduced, and the abrasion of the inner hole conical surface is further reduced; in addition, the annular groove is located in the middle, so that the front part and the rear part of the conical surface of the cutter handle are in contact with the conical surface of the inner hole for a long time, and the positioning requirement of the cutter handle mechanism is met.
Furthermore, the taper of the inner hole conical surface is 7:24, and the precision grade of the taper is less than or equal to 8.
Has the advantages that: the precision of the machining process can be guaranteed under the taper, the cutting force borne by the machining process of the cutter handle mechanism can be overcome by the tension and pressure friction force exerted on the cutter handle mechanism by the main shaft device under the taper, the vibration of the rotating shaft caused by the cutting force is reduced, and the service life of the rotating shaft is prolonged.
Furthermore, can dismantle on the non-permanent magnetism section and be connected with the position sleeve, a plurality of pin is with position sleeve fixed connection in the pivot, and every pin all radially sets up along the pivot.
Has the advantages that: when this scheme of adoption, because of just having the non-permanent magnetism section originally on the rotor that has now, but the length of non-permanent magnetism section is long inadequately, can be under the condition of not changing current rotor after the position sleeve installation, only newly increase a position sleeve just can install original rotor fast and firmly in the pivot, reduce the installation degree of difficulty and reduce improvement cost.
Further, the stator comprises a front portion, a middle portion and a rear portion, a cooling groove is formed in the middle of the stator, the outer diameter of the front portion of the stator is the smallest, the outer diameter of the rear portion of the stator is the largest, a mounting surface and a protruding surface are arranged on the shell, the mounting surface is in interference fit with the outer surface of the rear portion of the stator, the outer surface of the front portion of the stator is in interference fit with the protruding surface, and the middle portion of the stator is in clearance fit with the mounting surface.
Has the advantages that: in the prior art, because the rotating shaft has high rotating speed when the main shaft device operates, and the rotating shaft and the rotor can generate a large amount of heat when operating, the temperature inside the shell rises, the overall thermal state characteristic and dynamic characteristic of the main shaft device are deteriorated, and the normal work of the main shaft device is influenced, a cooling groove is formed on the surface of a stator matched with the shell in the prior art, and the cooling purpose is achieved by continuously injecting cooling liquid into the cooling groove; for guaranteeing that the coolant liquid can not reveal, need stator surface and casing closely to laminate, however stator length is longer, often has when the casing is advanced in the stator installation to assemble not to go into or the assembly degree of difficulty is big and the problem of consuming time and difficultly. After this scheme of adoption, during the stator installation, the stator front portion embolias earlier in the casing, because of the anterior external diameter of stator is minimum, so when the anterior route mounting surface of stator, the stator can not produce the friction with the casing, only can increase the installation degree of difficulty after the anterior contact of stator touches protruding face or stator rear portion installation face, so compare prior art, this scheme can reduce the installation degree of difficulty of stator.
In addition, this scheme passes through the interference fit of stator front portion, stator rear portion and casing, has guaranteed that the cooling bath that the stator middle part contains is in the closed section, has avoided the condition that cooling liquid reveals in the cooling bath, and stator middle part and casing intermittent type cooperate for the stator installation process can not lead to the fact wearing and tearing to stator middle part surface, and the metal fillings that the shape of avoiding wearing and tearing influence cooling bath also can avoid wearing and tearing to produce drop to the cooling bath in.
Further, the length of the middle part of the stator is more than half of the total length of the stator.
Has the advantages that: the stator middle part length is great, and the assembly difficulty of stator is further reduced to being favorable to.
Further, the front portion of the stator and the rear portion of the stator are both provided with annular grooves, and the shell is provided with oil injection holes communicated with the annular grooves.
Has the advantages that: through the settlement of ring groove, make things convenient for lubricating oil to pour into from the oil filler point into, further be favorable to reducing the installation degree of difficulty at stator front portion and stator rear portion.
Further, a communication channel is arranged on the shell and communicates the two oil injection holes.
Has the advantages that: through the setting of intercommunication passageway, make things convenient for once only to two oil filler points oiling simultaneously for the efficiency that lubricating oil pours into.
Further, the stator comprises a stator body and a stator sleeve, the stator body is fixedly sleeved in the stator sleeve, the cooling groove is formed in the stator sleeve, and the stator sleeve is detachably connected with the shell.
Has the advantages that: when the stator is in failure and needs to be replaced, the rotor or the stator sleeve can be replaced according to the position of the failure, so that the cost for replacing the stator is reduced; in addition, the stator sleeve is detachably connected with the shell, so that the connection stability of the stator and the shell is enhanced.
Further, fixedly connected with stator fixed end cover on the stator cover, stator fixed end cover can dismantle the connection on the casing, and stator fixed end covers to dismantle again simultaneously and is connected with the installation cover, and pivot one end is rotated and is connected in the installation cover, and the pivot other end is rotated and is connected on the casing.
Has the advantages that: through the arrangement of the stator fixing end cover, the stator sleeve and the mounting sleeve can be fixed on the stator fixing end cover, so that the mounting and dismounting of the stator sleeve and the mounting sleeve are facilitated; in addition, the installation cover can be dismantled with the fixed end cover of stator and be connected, and the fixed end cover of stator can be dismantled with the casing again and be connected, and the installation cover can be dismantled with the casing and be connected in other words, and the pivot both ends are rotated respectively and are connected on casing and installation cover for the rotation of pivot is equivalent to going on a part, is favorable to pivot pivoted stability.
Furthermore, one end of the shell, which is close to the mounting sleeve, is fixedly connected with a mounting block, the mounting block is fixedly connected with the shell, and the mounting block is used for fixing a driver of the broach mechanism.
Has the advantages that: the broach mechanism is arranged on the main shaft device through the mounting block, so that the main shaft device has more comprehensive functions.
Drawings
FIG. 1 is an isometric view of an embodiment of the utility model;
FIG. 2 is a front cross-sectional view of an embodiment of the present invention;
FIG. 3 is an enlarged view of portion A of FIG. 2;
FIG. 4 is a top view of an embodiment of the present invention;
FIG. 5 is a schematic view of the connection between the rotating shaft and the rotor according to the embodiment of the present invention;
FIG. 6 is a schematic view of a connection between a rotating shaft and a rotor at another viewing angle according to an embodiment of the present invention;
fig. 7 is a front sectional view of fig. 5.
Detailed Description
The following is further detailed by way of specific embodiments:
reference numerals in the drawings of the specification include: the device comprises a rotating shaft 1, an inner hole conical surface 11, an annular groove 12, a positioning sleeve 2, a rotor 3, a permanent magnet section 31, a non-permanent magnet section 32, a stator sleeve 4, a cooling groove 41, an annular groove 42, a stator body 5, a knife handle mechanism 6, a shell 20, a mounting surface 21, a convex surface 22, a water inlet channel 23, a water outlet channel 24, an oil filling hole 25, a communicating channel 26, a stator fixing end cover 7, a mounting sleeve 8, a rear bearing 9, a mounting block 30, a driver 40 and a pull rod 50.
Examples
Embodiment basically as shown in fig. 1 to 6, a spindle device of a machine tool comprises a housing 20, a rotating shaft 1, a rotor 3 and a stator, wherein a mounting surface 21 and a convex surface 22 are integrally formed in the housing 20, and the inner diameter of the mounting surface 21 is larger than that of the convex surface 22; the stator includes stator body 5 and stator cover 4, and stator body 5 is fixed to be cup jointed in stator cover 4 (can adopt the mode of bonding), can dismantle on stator cover 4 to be connected with stator fixed end cover 7 (for example adopt the screw to form fixed connection), and stator fixed end cover 7 passes through the screw and forms fixed connection with casing 20.
The stator sleeve 4 comprises a front part, a middle part and a rear part, wherein a spiral cooling groove 41 is formed in the middle part of the stator sleeve 4, the outer diameter of the front part of the stator sleeve 4 is the minimum, the outer diameter of the rear part of the stator sleeve 4 is the maximum, the mounting surface 21 is in interference fit with the outer surface of the rear part of the stator sleeve 4, the outer surface of the front part of the stator sleeve 4 is in interference fit with the convex surface 22, the middle part of the stator sleeve 4 is in clearance fit with the mounting surface 21, and the length of the middle part of the stator is greater than half of the total length of the stator.
The shell 20 is provided with a water inlet channel 23 and a water outlet channel 24, one end of the water inlet channel 23 is a water inlet, the cooling grooves 41 are communicated, one end of the water outlet channel 24 is a water outlet, and the water inlet and the water outlet are respectively positioned at two end parts of the spiral cooling groove 41.
The front part of the stator sleeve 4 and the rear part of the stator sleeve 4 are both provided with annular grooves 42, the shell 20 is provided with oil holes 25 communicated with the annular grooves 42, plugs can be installed on the oil holes 25, the shell 20 is also provided with a communicating channel 26, and the communicating channel 26 communicates the two oil holes 25.
The stator fixing end cover 7 is connected with a mounting sleeve 8 through a screw fixedly, a rear bearing 9 is fixedly sleeved in the mounting sleeve 8, one end of the rotating shaft 1 is rotatably connected with the mounting sleeve 8 through the rear bearing 9, and the other end of the rotating shaft 1 is rotatably connected with the shell 20 through a front bearing arranged on the rotating shaft. The left side of the shell 20 is fixedly connected with an installation block 30 through a screw, the installation block 30 is fixedly connected with the shell 20, the broach mechanism comprises a pull rod 50 and a driver 40, the driver 40 drives the pull rod 50 to axially move on the rotating shaft 1, the driver 40 can adopt an oil cylinder, and the installation block 30 is used for fixing the driver 40 of the broach mechanism.
The rotor 3 is integrally formed with a permanent magnet section 31 and a non-permanent magnet section 32, the two ends of the permanent magnet section 31 are the non-permanent magnet sections 32, the outer diameter of each non-permanent magnet section 32 is smaller than that of the permanent magnet section 31, the permanent magnet section 31 is provided with a winding (not shown in the figure), the end part of one non-permanent magnet section 32 is fixedly connected with a positioning sleeve 2, the positioning sleeve 2 is fixedly connected with the non-permanent magnet section 32 through a plurality of screws, each screw is axially arranged, the plurality of screws are uniformly distributed along the circumferential direction of the rotating shaft 1, and the length of the screw extending into the non-permanent magnet section 32 is smaller than or equal to half of the length of the non-permanent magnet section 32; the locating sleeve 2 is fixedly connected with the rotating shaft 1 through a plurality of pins, each pin is radially distributed in the rotating shaft 1, the plurality of pins are uniformly distributed along the circumferential direction of the rotating shaft 1, and the rotor 3 is in clearance fit with the rotating shaft 1.
An inner hole conical surface 11 is integrally formed at one end of the rotating shaft 1, which is used for installing the cutter handle mechanism 6, an annular groove 12 is formed in the inner hole conical surface 11, the annular groove 12 is located in the middle of the inner hole conical surface 11, the taper of the inner hole conical surface 11 is 7:24, and the precision grade of the taper is less than or equal to 8 grade.
The specific implementation process is as follows:
when adopting this embodiment, when installing rotor 3 into pivot 1, earlier the non-permanent magnetism section 32 and the position sleeve 2 of rotor 3 pass through the screw and form fixed connection, install the whole that position sleeve 2 and rotor 3 formed on pivot 1 together again, reuse pin at last with position sleeve 2 and pivot 1 fixed connection, accomplish the fixed connection of rotor 3 on pivot 1.
The permanent magnet section 31 of the rotor 3 is used for generating a magnetic field, the non-permanent magnet section 32 is fixedly connected with the rotating shaft 1 through pins, and a plurality of pins are uniformly distributed in the circumferential direction of the rotating shaft 1, so that the symmetry of the rotor 3 on the rotating shaft 1 is ensured, and the rotor 3 is in clearance fit with the rotating shaft 1, so that the process of mounting the rotor 3 is simple and rapid; in addition, the stability of the rotor 3 and the installation of the rotating shaft 1 is improved due to the installation of the pins, compared with the prior art, the firm installation requirement and the requirement of the assembly difficulty are both considered, and meanwhile, the requirement that the magnetic field of the permanent magnet section 31 is not influenced is also met.
When the stator is installed, the stator body 5 and the stator sleeve 4 are fixedly connected, and then the whole formed by the stator body 5 and the stator sleeve 4 is sleeved on the shell 20, when the stator is sleeved in the step, the factor front part is sleeved into the shell 20 firstly, and the outer diameter of the front part of the stator sleeve 4 is the minimum, so that the stator sleeve 4 cannot generate friction with the shell 20 when the front part of the stator sleeve 4 approaches the installation surface 21, and the installation difficulty is increased only when the front part of the stator sleeve 4 contacts the convex surface 22 or the rear part of the stator sleeve 4 contacts the installation surface 21, so compared with the prior art, the installation difficulty of the stator can be reduced in the embodiment; in specific implementation, in order to reduce the difficulty in mounting the front portion of the stator sleeve 4 and the convex surface 22 and the difficulty in mounting the rear portion of the stator sleeve 4 and the mounting surface 21, lubricating oil may be injected into the annular groove 42 through the communication channel 26 when the stator sleeve 4 is mounted, so as to further reduce the difficulty in mounting.
In addition, this embodiment is through the interference fit of stator cover 4 anterior, 4 backs of stator cover and casing 20, has guaranteed that the cooling bath 41 that the middle part of stator cover 4 contains is in the closed section, has avoided the condition that the cooling liquid in cooling bath 41 revealed, and 4 middle parts of stator cover and casing 20 intermittent type cooperations for 4 installation processes of stator cover can not lead to the fact wearing and tearing to the outer surface in the middle part of stator cover 4, and the metal fillings that the shape of avoiding wearing and tearing influence cooling bath 41 also can avoid wearing and tearing to produce drop in cooling bath 41.
In the embodiment, the annular groove 12 is formed in the inner hole conical surface 11 of the rotating shaft 1, so that the contact area between the inner hole conical surface 11 and the cutter handle conical surface is reduced, and the abrasion of the inner hole conical surface 11 is further reduced; in addition, the annular groove 12 is located in the middle, so that the front part and the rear part of the conical surface of the cutter handle are in contact with the conical surface 11 of the inner hole for a long time, and the positioning requirement of the cutter handle mechanism 6 is met.
The foregoing is merely an example of the present invention and common general knowledge of known specific structures and features of the embodiments is not described herein in any greater detail. It should be noted that, for those skilled in the art, without departing from the structure of the present invention, several changes and modifications can be made, which should also be regarded as the protection scope of the present invention, and these will not affect the effect of the implementation of the present invention and the practicability of the patent. The scope of the claims of the present application shall be determined by the contents of the claims, and the description of the embodiments and the like in the specification shall be used to explain the contents of the claims.
Claims (10)
1. The utility model provides a spindle unit of lathe, includes casing, pivot, rotor and stator, and the pivot front end is equipped with the hole conical surface, its characterized in that: the inner hole conical surface is provided with an annular groove which is positioned in the middle of the inner hole conical surface; the rotor is provided with a permanent magnet section and a non-permanent magnet section, the permanent magnet section is provided with a winding, the non-permanent magnet section is detachably connected to the rotating shaft, and the rotor is in clearance fit with the rotating shaft.
2. The spindle device of a machine tool according to claim 1, characterized in that: the taper of the inner hole conical surface is 7:24, and the precision grade of the taper is less than or equal to 8.
3. The spindle device of a machine tool according to claim 1, characterized in that: the non-permanent-magnet section is detachably connected with a locating sleeve, the locating sleeve is fixedly connected to the rotating shaft through a plurality of pins, and each pin is radially arranged along the rotating shaft.
4. The spindle device of a machine tool according to claim 1, characterized in that: the stator comprises a front portion, a middle portion and a rear portion, a cooling groove is formed in the middle of the stator, the outer diameter of the front portion of the stator is the smallest, the outer diameter of the rear portion of the stator is the largest, a mounting surface and a protruding surface are arranged on the shell, the mounting surface is in interference fit with the outer surface of the rear portion of the stator, the outer surface of the front portion of the stator is in interference fit with the protruding surface, and the middle portion of the stator is in clearance fit with the mounting surface.
5. The spindle device of a machine tool according to claim 4, wherein: the length of the middle part of the stator is more than half of the total length of the stator.
6. The spindle device of a machine tool according to claim 4, wherein: the stator front portion and the stator rear portion are provided with annular grooves, and the shell is provided with oil injection holes communicated with the annular grooves.
7. The spindle device of a machine tool according to claim 6, wherein: and a communicating channel is arranged on the shell and communicates the two oil injection holes.
8. The spindle device of a machine tool according to claim 4, wherein: the stator comprises a stator body and a stator sleeve, the stator body is fixedly sleeved in the stator sleeve, the cooling groove is formed in the stator sleeve, and the stator sleeve is detachably connected with the shell.
9. The spindle device of a machine tool according to claim 8, wherein: the stator is sheathe in fixedly connected with stator stationary cover, and stator stationary cover can dismantle the connection on the casing, and stator stationary cover is last to dismantle again to be connected with the installation cover simultaneously, and pivot one end is rotated and is connected in the installation cover, and the pivot other end is rotated and is connected on the casing.
10. The spindle device of a machine tool according to claim 9, wherein: the one end fixedly connected with installation piece that the casing is close to the installation cover, installation piece and casing fixed connection, installation piece are used for the driver of fixed broach mechanism.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202122084601.3U CN216263494U (en) | 2021-08-31 | 2021-08-31 | Main shaft device of machine tool |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202122084601.3U CN216263494U (en) | 2021-08-31 | 2021-08-31 | Main shaft device of machine tool |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN216263494U true CN216263494U (en) | 2022-04-12 |
Family
ID=81063686
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202122084601.3U Active CN216263494U (en) | 2021-08-31 | 2021-08-31 | Main shaft device of machine tool |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN216263494U (en) |
-
2021
- 2021-08-31 CN CN202122084601.3U patent/CN216263494U/en active Active
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