CN109412336B

CN109412336B - Motor and control method thereof

Info

Publication number: CN109412336B
Application number: CN201811488107.XA
Authority: CN
Inventors: 尹洁; 应军江; 李晓宇; 王银萍
Original assignee: Zhejiang Jiang Yu Motor Co ltd
Current assignee: Zhejiang Jiang Yu Motor Co ltd
Priority date: 2018-12-06
Filing date: 2018-12-06
Publication date: 2020-05-12
Anticipated expiration: 2038-12-06
Also published as: CN109412336A

Abstract

The invention provides a motor and a control method thereof. The motor comprises a shell, a stator and a rotor; the stator is arranged in the shell; the rotor is arranged at the radial inner side of the stator; the shell is provided with a rear end cover, and a shaft end groove is formed in the rear end cover; the rotor is provided with an output shaft, and the rear end of the output shaft is inserted into the shaft end groove; the motor further includes: an anti-play device having a primary and a secondary; the primary is arranged on the peripheral wall of the shaft end groove, and the secondary is arranged at the rear end of the output shaft; and a play detection device configured to detect a displacement between the real-time position and the initial position of the output shaft to control the primary according to the displacement, thereby keeping the output shaft at the initial position. Due to the fact that the anti-shifting device and the shifting detection device are arranged, when the shifting detection device detects that the output shaft axially shifts, current supplied to the primary side can be controlled, the secondary side is promoted to drive the output shaft to move in the direction opposite to the axial shifting direction, axial shifting is prevented from occurring, and particularly, the rotation of the output shaft cannot be influenced.

Description

Motor and control method thereof

Technical Field

The invention relates to the field of motors, in particular to a motor and a control method thereof.

Background

At present, in the use process of the motor, a special phenomenon that a rotor moves through a shaft exists. The rotor of the motor is shifted out of the stator core and is axially displaced, which is called as a rotor shifting shaft. Normally, the two ends of the stator core and the rotor core are aligned, or the rotor is slightly shorter than the stator core. When the rotor core is shifted out of the stator core by 5mm or more, the three-phase no-load current of the motor is obviously increased, and after the load is carried, the stator current exceeds the rated current value, so that the motor is overheated. While a matrix of uneven but regular hum is emitted. If the rotor of the motor seriously breaks the shaft, the motor can not drive the load to operate at all.

Disclosure of Invention

The present invention is directed to overcoming at least one of the disadvantages of the conventional motor and providing a motor and a control method thereof capable of preventing the motor from axial play as much as possible.

To this end, the invention proposes a motor, including body, stator and trochanter; the stator is arranged in the shell; the rotor is arranged on the radial inner side of the stator; the shell is provided with a rear end cover, and a shaft end groove is formed in the rear end cover; the rotor is provided with an output shaft, and the rear end of the output shaft is inserted into the shaft end groove; characterized in that, the motor still includes:

an anti-drunkenness device having a primary and a secondary; the primary stage is mounted on the peripheral wall of the shaft end groove, and the secondary stage is mounted at the rear end of the output shaft; and

a play detection device configured to detect a displacement between a real-time position and an initial position of the output shaft to control the primary in accordance with the displacement to thereby keep the output shaft at the initial position.

Further, the secondary is a permanent magnet and is mounted on the output shaft.

Further, a coil slot is formed in the circumferential wall of the shaft end slot, and the primary winding coil is mounted in the coil slot.

Furthermore, the shell is provided with a front end cover, and the front end cover is provided with a shaft hole;

the anti-play device is also provided with a primary stage arranged at the front part of the wall surface of the shaft hole and a secondary stage correspondingly arranged on the output shaft.

Further, the rotor further includes:

the damping structure comprises two first rolling bearing assemblies, a damping mechanism and a damping mechanism, wherein each first rolling bearing assembly comprises a first rolling bearing and a damping structure arranged on the outer peripheral surface of the first rolling bearing; and both ends of the output shaft are mounted to the housing through the first rolling bearing assembly;

a rotor shaft sleeve including an inner cylinder portion, an outer cylinder portion, and a connecting portion; the outer cylinder part is arranged on the radial outer side of the inner cylinder part; the connecting part is arranged between the inner cylinder part and the outer cylinder part so as to connect the middle part of the inner cylinder part and the middle part of the outer cylinder part; the output shaft is arranged in a central hole of the inner cylinder part, and the output shaft is connected with the inner cylinder part through a key transmission structure;

a rotor core mounted to the outer cylindrical portion; and

two second rolling-bearing assemblies, each of which comprises a second rolling bearing and a connecting bracket; the two second rolling bearings are respectively arranged at two ends of the inner cylinder part, and the outer ring of each second rolling bearing is arranged on the shell through one connecting bracket.

Further, the shock-absorbing structure is a shock-absorbing pad, a damping pad or a compression spring with a plurality of uniform distribution on the first rolling bearing.

Further, the connection bracket includes:

a fixing ring to which an outer ring of the second rolling bearing is attached;

the fixed flange plate is arranged on the inner side of the shell and is coaxial with the rotor; and

and the spoke plates are connected to the fixing ring and the fixing flange plate.

Further, each of the webs has:

a horizontal extension section connected to an outer circumferential surface of the fixing ring;

the vertical extension section is connected to one side, facing the rotor, of the fixed flange plate; and

the two ends of the snake-shaped extension section are respectively connected with the vertical extension section and the horizontal extension section and are tangent with the vertical extension section and the horizontal extension section; and the serpentine extension is integrally arched toward the end of the output shaft adjacent thereto.

Furthermore, the stator is also provided with a plurality of radiating hole groups, each radiating hole group is provided with two first strip-shaped holes arranged at two sides of one corresponding stator slot, each first strip-shaped hole extends along the axial direction of the stator, and the opening faces the radial outer side of the stator;

a plurality of second strip-shaped holes are formed in the shell, and each second strip-shaped hole is arranged corresponding to one first strip-shaped hole; and is

The motor further includes:

each first semiconductor refrigeration piece is inserted into one first strip-shaped hole, and the cold end surface of each first semiconductor refrigeration piece faces to the stator slot adjacent to the first semiconductor refrigeration piece;

the external heat dissipation device is arranged on the outer surface of the shell; and

the first heat conducting fins are connected with the external heat dissipation device, one of the second strip-shaped holes and one of the first strip-shaped holes correspond to the first strip-shaped holes, and the hot end faces of the first semiconductor refrigeration pieces in the first strip-shaped holes are in contact and abut against the first heat conducting fins.

The present invention also provides a control method for any one of the above motors, comprising:

detecting the displacement between the real-time position and the initial position of the output shaft in real time;

controlling the primary in accordance with the displacement, thereby maintaining the output shaft at the initial position.

In the motor, the play detection device and the play prevention device are arranged, so that when the play detection device detects that the axial play of the output shaft occurs, the current supplied to the primary stage is controlled, and the secondary stage drives the output shaft to move in the direction opposite to the axial play direction so as to prevent the axial play, and particularly, the rotation of the output shaft is not influenced.

Furthermore, in the motor, the two connecting supports and the two second rolling bearings are used for fixedly mounting the rotor of the motor, the two first rolling bearings and the damping structure are used for assisting in mounting the rotor, the motor has certain elasticity and flexibility and enough supporting strength, the stability of the rotor during working is obviously improved, the stability of power transmission between the output shaft and the transmission part is further ensured, and the output shaft can be prevented from being disturbed in the circumferential direction.

Furthermore, the semiconductor refrigeration sheet is arranged in the slit formed in the stator slot and aligned with the winding, and the heat dissipated by the winding can be rapidly led out to an external heat dissipation device through the heat conduction sheet; further, through the operating power value of controlling first semiconductor refrigeration piece, make the heat dissipation of motor and generating heat of motor reach effective reasonable unity, make full use of different heat dissipation power's first semiconductor refrigeration piece, guarantee the radiating rationality of motor, the place that the heat is many dispels the heat fast promptly, the place that the heat is few dispels the heat slowly, reach the heat dissipation and generate heat unified, and then the temperature that can make every position department of motor tends to unanimity to guarantee the performance of motor. The arrangement of the plurality of first semiconductor refrigerating pieces enables the power value of each first semiconductor refrigerating piece not to be large, and the existing semiconductor refrigerating pieces with small size can be fully utilized.

The above and other objects, advantages and features of the present invention will become more apparent to those skilled in the art from the following detailed description of specific embodiments thereof, taken in conjunction with the accompanying drawings.

Drawings

Some specific embodiments of the invention will be described in detail hereinafter, by way of illustration and not limitation, with reference to the accompanying drawings. The same reference numbers in the drawings identify the same or similar elements or components. Those skilled in the art will appreciate that the drawings are not necessarily drawn to scale. In the drawings:

FIG. 1 is a schematic block diagram of an electric machine according to one embodiment of the present invention;

FIG. 2 is a schematic partial block diagram of the motor shown in FIG. 1;

fig. 3 is a schematic structural view of a stator core in a stator of the motor shown in fig. 1;

fig. 4 is a schematic partial cross-sectional view of the stator core shown in fig. 3;

FIG. 5 is a schematic block diagram of one copper bar conductor mounted on a stator core;

FIG. 6 is a schematic cross-sectional view of the motor shown in FIG. 1;

FIG. 7 is a schematic enlarged view at A in FIG. 6;

FIGS. 9 and 8 are schematic structural views of two connecting brackets, respectively;

FIG. 10 is a schematic block diagram of a motor according to one embodiment of the present invention;

FIG. 11 is a schematic cross-sectional view of a connection structure between a base and a housing;

fig. 12 is a schematic partial structural view of the rotor.

Detailed Description

Fig. 1 is a schematic structural view of a motor according to an embodiment of the present invention. As shown in fig. 1, and with reference to fig. 2-12, an embodiment of the present invention provides an electric machine. Generally, the motor may include a housing 100, a stator 200, and a rotor 300. The case 100 generally has a main case 110 and end caps, such as a case front cap 120 and a case rear cap 130, disposed at both ends of the main case 110. The stator 200 is disposed in the housing 100. The rotor 300 is disposed radially inward of the stator 200. The core of stator 200 has stator slots 210, and stator slots 210 are used to wind windings 240.

In some embodiments of the present invention, in order to improve the heat dissipation performance of the motor, the stator 200 further has a plurality of heat dissipation hole groups, each of which has two first bar-shaped holes 220 disposed at both sides of a corresponding stator slot 210. Each first bar hole 220 extends in the axial direction of the stator 200, and opens toward the radially outer side of the stator 200. The housing 100 is provided with a plurality of second bar-shaped holes, and each second bar-shaped hole is arranged corresponding to one first bar-shaped hole 220.

The motor further includes a plurality of first semiconductor cooling fins 510, an external heat sink 520, and a plurality of first heat-conducting fins 530. Each first semiconductor chilling plate 510 is inserted into one first bar-shaped hole 220, and the cold end surface of each first semiconductor chilling plate 510 faces the stator slot 210 adjacent thereto. That is, both sides of each stator slot 210 are cold end faces of the first semiconductor chilling plates 510 to accelerate heat dissipation of the windings. The external heat sink 520 may be disposed on an outer surface of the housing 100. Each first heat conducting fin 530 is connected to the external heat sink 520, and each first heat conducting fin 530 is inserted into one second strip-shaped hole and one corresponding first strip-shaped hole 220, and contacts and abuts against the hot end surface of the first semiconductor chilling plate 510 in the first strip-shaped hole 220. Moreover, the first semiconductor chilling plate 510 and the first heat-conducting plate 530 are completely filled to close the first strip-shaped hole 220, and the first heat-conducting plate 530 needs to be completely filled to the second strip-shaped hole.

In the motor of the embodiment of the invention, the first semiconductor refrigeration sheet 510 is arranged in the slit formed in the stator slot 210 and aligned with the winding 240, and the heat dissipated by the winding 240 and the like can be rapidly conducted out to the external heat dissipation device 520 through the heat conduction sheet 530, so that the heat dissipation efficiency of the motor is high, and the economic and technical indexes of the motor, such as efficiency, torque and the like, are ensured. The two first semiconductor refrigeration pieces which are symmetrically arranged can enable the winding to dissipate heat uniformly as much as possible, and the motor overall heat dissipation structure which is uniformly distributed can ensure that the motor dissipates heat uniformly on the whole and further improves the motor energy efficiency.

In some preferred embodiments of the present invention, the external heat sink 520 comprises a plurality of second semiconductor chilling plates, and the cold end face of each second semiconductor chilling plate abuts against the outer surface of the housing 100. And the cold end face of each second semiconductor chilling plate is radially outward of one stator slot 210. Of course, in some alternative embodiments, the cold end face of each second semiconductor chilling plate is radially outward of the area between two adjacent stator slots 210. Each second semiconductor chilling plate is connected to a first heat conducting plate 530 at each side edge of its cold side face.

In other preferred embodiments of the present invention, the external heat sink 520 includes a third semiconductor cooling fin. The third semiconductor refrigeration piece is cylindrical and sleeved on the shell 100, and the cold end face of the third semiconductor refrigeration piece is in contact with and abutted against the peripheral wall of the shell 100. When the external heat dissipation device 520 also adopts the semiconductor refrigeration piece, the heat dissipation effect of the motor is further ensured. In addition, the cold and hot end of the semiconductor refrigeration piece is exchanged, so that the problem that lubricating oil in the motor is frozen can be effectively solved, if the motor is used in cold regions, the motor can be preheated internally, the preheating speed is high, and the motor can be effectively protected.

In some further embodiments of the present invention, the housing 100 is provided with a mounting groove for mounting a plurality of second semiconductor chilling plates or mounting a third semiconductor chilling plate, and a hot end surface of each second semiconductor chilling plate or a hot end surface of each third semiconductor chilling plate is in thermal contact with an outer surface of the housing 100. The outer surface of the housing 100 is provided with heat dissipation grooves. The arrangement can fully utilize the outer surface of the shell 100 to dissipate heat, so that the hot end surfaces of the second semiconductor and the third semiconductor are not provided with heat dissipation fins, and the effective volume of the motor can be reduced. Of course, those skilled in the art may also arrange heat dissipation fins on the hot side of the second semiconductor and the third semiconductor. Furthermore, optionally, each first semiconductor chilling plate 510 is also inserted into a corresponding second strip-shaped hole. In order to fully utilize the heat dissipation function of the housing, it is preferable that the first semiconductor chilling plates 510 are not inserted into the corresponding second strip-shaped holes. Each of the first bar holes 220 has a length of 0.5 to 0.7 times the length of the stator slot 210 and is located at the middle of the stator 200 in the length direction thereof. The length of each second bar hole is 0.6 to 0.8 times the length of the first bar hole 220.

Further, a plurality of second heat-conducting fins are further disposed between the region of the stator 200 outside each stator slot 210 and the inner wall of the casing 100. Alternatively, a plurality of second heat conductive sheets may be disposed between each region of the outer side surface of the stator 200 and the inner wall of the casing 100. Also, a plurality of through holes, each having a diameter of 0.05mm to 0.15mm, are provided on a region of each first heat conductive sheet 530 between the stator 200 and the case 100 and on each second heat conductive sheet. By this arrangement, it is possible to prevent a closed region from being present between the stator 200 and the housing 100, which may affect the motor performance, such as the lubricant oil entering the region.

In some embodiments of the present invention, as shown in fig. 3 and 4, each stator 200 further has a plurality of oil hole groups, each oil hole group has 3 to 5 rectangular oil holes 230 spaced apart in an axial direction of the stator 200, and the rectangular oil holes 230 of each oil hole group communicate an inner side of the stator 200 with a side of one first bar-shaped hole 220 facing the stator slot 210. The rectangular oil hole 230 is arranged so that the lubricating oil carried by the rotor 300 enters the oil hole, exchanges heat with the semiconductor refrigeration sheet, and flows out of the rectangular oil hole 230 under the action of motion vibration of the motor or gravity of the motor, so that the temperature of the lubricating oil is reduced. For example, the lubricant oil in the rectangular oil hole 230 at the upper side of the motor may be vibrated by the motion of the motor or depend on its own weight. The lubricant oil in the rectangular oil hole 230 at the lower side may be shaken out by the motion vibration of the motor.

The long side surface of each rectangular oil hole 230 extends in the axial direction of the stator 200. And, the two long side surfaces of each rectangular oil hole 230 include a first long side surface and a second long side surface, and the first long side surface is located at an upstream side of the second long side surface in a rotation direction of the rotor 300. One side of the first long side surface close to the mover is provided with a first inclined chamfer, and one side of the second long side surface close to the mover is provided with a second inclined chamfer to form a first chamfer surface 231 and a second chamfer surface 232 respectively. The inclination angle of the second inclined chamfer is larger than that of the first inclined chamfer. The oil drops carried by the rotor 300 fall to the first long side surface under the action of centrifugal force, and then the oil drops in the rectangular oil hole 230 are extruded out, and the second inclination angle is larger, so that the oil drops can move smoothly. Wherein, the size of the inclined chamfer refers to the difference of the included angles between 180 degrees and the corresponding long side surface.

In some embodiments of the present invention, as shown in fig. 5, the stator winding 240 is made of a copper bar conductor 241, and an insulating varnish is disposed outside the copper bar conductor 241; the stator winding comprises a plurality of straight line segments 242, and at least one connecting segment 243 connecting two straight line segments 242; at least one straight segment 242 is disposed within each stator slot. The stator also has a plurality of first insulating sleeves 244 and a plurality of second insulating sleeves 245. Each first insulating sleeve 244 is made of a flexible material; each end of each stator slot is provided with at least one first insulating sleeve 244 to be fitted over one straight section 242 and the corresponding connecting section 243. Each second insulating sleeve 245 is made of a flexible material; each second insulating sleeve 245 is fitted over the middle of each connecting section 243.

Further, the end of each first insulating sleeve 244 located inside the corresponding stator slot has an inner diameter smaller than that of the other end. Each stator slot is provided with a plurality of straight segments 242, each end of each stator slot has a plurality of first insulating sleeves 244, and the ends of the plurality of first insulating sleeves 244 located inside the corresponding stator slot are integrally formed, so that the firmness of installation can be improved, the diversity of bending directions of the stator can be ensured, and the stator is suitable for various coils.

In some embodiments of the present invention, the first and second

insulating sleeves

244 and 245 each include an insulating paper and an insulating film disposed on both sides of the insulating paper. In some embodiments, the insulating film includes: 80 parts of polyimide, 80 parts of polycarbonate, 5 parts of zinc oxide, 2 parts of a defoaming agent, 2 parts of a dispersing agent, 2 parts of sodium hexametaphosphate, 0.5 part of alkyl imidazoline, 0.4 part of polyoxyethylene ether, 50 parts of modified cross-linked polyethylene, 10 parts of ethylene bis-oleic amide, 20 parts of ceramic fiber, 15 parts of modified montmorillonite, 5 parts of rare earth elements and 3 parts of a silane coupling agent. In further alternative embodiments, the insulating film includes: 95 parts of polyvinyl chloride, 2-5 parts of dioctyl adipate, 2-8 parts of dioctyl phthalate, 0.2-0.6 part of zinc stearate, 0.15-0.25 part of paraffin, 3-10 parts of ethylene-vinyl acetate copolymer, 0.1-0.2 part of dipentaerythritol ester, 0.2-0.5 part of acetyl tributyl citrate, 1-3 parts of lead silicate coprecipitated by silicic acid, 0.2-0.6 part of barium stearate, 0.01-0.02 part of diphenol propane and 0.1-0.5 part of N-phenyl maleimide.

The first insulating sleeve and the second insulating sleeve can guarantee that the insulating property of the copper bar conductor can be guaranteed even if insulating paint is damaged in the bending process of the copper bar conductor, so that the motor can be protected, and the service life of the motor is prolonged. The end parts, located on the inner sides of the corresponding stator slots, of the first insulation sleeves are integrally formed, the inner end inner diameter is larger than the outer end inner diameter, the firmness of installation of the first insulation sleeves can be guaranteed, and the first insulation sleeves cannot be separated from the end parts of the stator slots due to vibration of the motor and the like. Moreover, the outer ends are arranged in a separated mode, so that the bending diversity of the plurality of copper bar conductors can be guaranteed, and the interference on the positions of the copper bar conductors can be avoided. The special components of the insulating film are high temperature resistant, have a good heat dissipation function, and are convenient for heat on the copper bar conductor to be rapidly transferred to the outer sides of windings such as a stator.

In some embodiments of the present invention, as shown in fig. 6 to 9, the rotor 300 may include an output shaft 310, a rotor bushing 320, a rotor core 330, two first rolling bearing assemblies 340, and two second rolling bearing assemblies 350.

Each of the first rolling bearing assemblies 340 includes a first rolling bearing 341, and a shock-absorbing structure 342 provided on an outer circumferential surface of the first rolling bearing 341. And both ends of the output shaft 310 are mounted to the housing 100 through the first rolling bearing assembly 340. Such as a front cover 120 and a rear cover 130 mounted to the housing 100.

Both end surfaces of the rotor bushing 320 have annular grooves so that the rotor bushing 320 includes an inner cylindrical portion 321, an outer cylindrical portion 322, and a connecting portion 323. The inner tube 321 is attached to the output shaft 310, the outer tube 322 is disposed radially outward of the inner tube 321, and the connection part 323 is disposed between the inner tube 321 and the outer tube 322 to connect the inner tube 321 and the outer tube 322. Specifically, the output shaft 310 is installed in a central hole of the inner cylinder 321, and the output shaft 310 and the inner cylinder 321 are in transmission connection through a spline transmission structure. The rotor core 330 is mounted to the outside of the rotor bushing 320. The rotor core 330 is attached to the outer cylinder 322.

Each second rolling bearing assembly 350 includes a second rolling bearing 351 and a connecting bracket 352. Two second rolling bearings 351 are provided at both ends of the inner cylinder portion 321, respectively, and the outer ring of each second rolling bearing 351 is mounted to the housing 100 by one connecting bracket 352.

In the embodiment of the present invention, the rotor 300 is configured in a special structure, so that the weight of the rotor 300 can be reduced, the rotor 300 can be conveniently processed and manufactured, the rotor core 330 is easily replaced, and the rotor shaft sleeve 320 can be used universally. In particular, after the weight of the rotor 300 is reduced, the power consumed for self-rotation is less, and the energy efficiency is remarkably improved.

Further, the two connecting supports 352 and the two second rolling bearings 351 are used for fixedly mounting the rotor 300 of the motor, the two first rolling bearings 341 and the damping structure 342 are used for achieving auxiliary mounting of the rotor 300, certain elasticity and flexibility are achieved, sufficient supporting strength is achieved, the stability of the rotor 300 during operation is remarkably improved, and the stability of power transmission between the output shaft 310 and a transmission part is further guaranteed. It is possible to prevent the problem that the supporting force may be insufficient by using only the conventional two rolling bearings provided at both ends of the output shaft 310 and directly attached to the housing 100. It is possible to prevent the lack of disturbance performance of the output shaft 310 by the plurality of rolling bearings, which may lock the rotation of the output shaft 310, affecting the life of the bearings and the rotor 300.

In some embodiments of the invention, vibration and noise during operation of the motor are further reduced. As shown in fig. 10 to 12, a base 600 may be provided under the case 100. The base 600 is provided with a supporting boss 610, and the casing 100 is provided with a supporting sleeve 620. The supporting sleeve 620 is sleeved on the supporting convex column 610, and a compression spring 630 and supporting pads located on the inner side and the outer side of the ring of the compression spring 630 are arranged between the bottom surface of the supporting sleeve 620 and the end surface of the supporting convex column 610.

Further, a plurality of pillars 640 are evenly distributed on the lower end face of the supporting sleeve 620, the lower end of each pillar 640 is provided with a plurality of limiting blocks, and each limiting block is wrapped with a damping pad. A plurality of connecting and limiting sleeves 650 are uniformly distributed on the outer side of the supporting convex column 610. Each limiting block is inserted into one connecting limiting sleeve 650, and an extension spring 660 positioned in the connecting limiting sleeve 650 is arranged between each limiting block and the base 600. Preferably, the number of the supporting bosses 610 and the number of the supporting sleeves 620 are four, and the four supporting bosses and the four supporting sleeves are arranged at the front end and the rear end of the casing 100; and each supporting boss 610, each supporting sleeve 620, each supporting column 640 and each connection limiting sleeve 650 are obliquely arranged.

In the embodiment of the present invention, the compression spring 630 and the extension spring 660 are used in combination, so that noise generated when the motor vibrates can be eliminated as much as possible, stability of the rotor 300 when the rotor vibrates can be ensured, the output shaft 310 is prevented from being separated from the transmission component connected thereto, and the output shaft can be quickly restored even if slightly separated, and subsequent transmission is not affected. That is, in this embodiment, the rotor 300 is fixed in a special manner, and the motor (the casing 100 and its internal structure) is fixed in a special manner with the base 600, which in combination can eliminate the noise when the motor vibrates as much as possible, ensure the stability when the rotor 300 vibrates, prevent the output shaft 310 from separating from the connected transmission component, and recover quickly even if slightly separated, without affecting the subsequent transmission.

In some embodiments of the present invention, the shock absorbing structure 342 is a shock absorbing pad, a damping pad or a compression spring having a plurality of rolling bearings 341 uniformly distributed therein. As shown in fig. 7 and 8, the connection bracket 352 may include a fixing ring 353, a fixing flange 354, and a plurality of webs 355. The outer ring of the second rolling bearing 351 is mounted to the fixed ring 353. The fixed flange 354 is mounted on the inner side of the housing 100 and is disposed coaxially with the rotor 300. A plurality of webs 355 are connected to the securing ring 353 and the securing flange 354.

In some embodiments of the present invention, each web 355 has a horizontal extension 356, a vertical extension 357, and a serpentine extension 358. The horizontally extending section 356 is connected to the outer peripheral surface of the fixing ring 353. The vertical extension 357 is connected to a side of the fixed flange 354 facing the rotor 300. The two ends of the snake-shaped extension 358 are respectively connected to the vertical extension 357 and the horizontal extension 356 and are tangent to the vertical extension 357 and the horizontal extension 356; and the serpentine extension 358 is generally arched toward the end of the output shaft 310 adjacent thereto. By adopting the snake-shaped extension section 358, the tension of the steel plate and the rebound force after compression can quickly reduce the vibration of the patent movement, the amplitude ratio is smaller, the rotor 300 can quickly reset the rotor 300, and the operation stability of the rotor 300 and the whole motor is ensured. In some alternative embodiments, each web 355 is a smoothly curved plate that arches toward the end of the output shaft 310 adjacent thereto.

In some embodiments of the present invention, as shown in fig. 12, the rotor core 330 may be provided with a front barrier 360 at the front end and a rear barrier 370 at the rear end. The front end of the outer cylinder 322 of the rotor bushing 320 is provided with a rib. When the rotor core is mounted, the front baffle 360 is fitted to the rib, the rotor core 330 is mounted to the outer cylinder 332, and the rear baffle 370 is fixed to the outer cylinder 322.

In some embodiments of the invention, to prevent axial play of the output shaft of the motor and the rotor as much as possible. The rear end cap 130 is formed with a shaft end groove 131. The rear end of the output shaft 310 is inserted into the shaft end groove 131. As shown in fig. 6, the motor further includes a play prevention means and a play detection means. The anti-tamper device has a primary 810 and a secondary 820; the primary 810 is mounted on the peripheral wall of the shaft end groove 131, and the secondary 820 is mounted on the rear end of the output shaft. The primary 810 and secondary 820 may form a structure that approximates a linear motor. The play detection means is configured to detect a displacement between the real-time position and the initial position of the output shaft to control the primary stage 810 according to the displacement to thereby keep the output shaft at the initial position. That is, when axial play occurs, the primary 810 and secondary 820 apply forces to the output shaft in opposite directions to return the output shaft to the initial position. Particularly, the force applied to the secondary 820 by the primary 810 is controlled in real time according to the displacement, the flexible control of the motor is realized by changing the force, the motor is adaptive to axial movement with different sizes, and the control is accurate through closed-loop feedback control. The play detection means may be a displacement detection means, for example, a laser distance sensor.

Further, the secondary 820 is a plurality of permanent magnets mounted to the output shaft. A coil groove is opened in the circumferential wall of the shaft end groove 131, and the winding coil of the primary stage 810 is mounted in the coil groove. The front end cover 120 is provided with a shaft hole; the anti-play device also has a primary stage disposed on a front portion of a wall surface of the shaft hole, and a secondary stage correspondingly disposed on the output shaft.

The embodiment of the invention also provides a control method. The control method can comprise the following steps: and detecting the displacement between the real-time position and the initial position of the output shaft in real time. The primary 810 is controlled according to the displacement, thereby keeping the output shaft at the initial position. For example, when the displacement of the axial play is large, a large restoring force may be generated using the primary 810 and secondary 820, and the restoring force becomes smaller as the play is gradually reduced. The force applied to the secondary 820 by the primary 810 is controlled in real time according to the displacement, the flexible control of the motor is realized by changing the force, the motor is suitable for axial movement with different sizes, and the control is accurate through closed-loop feedback control.

In some embodiments of the present invention, the motor further includes a plurality of temperature sensors (not shown), each of which is disposed at a rear end of one of the second bar-shaped holes to detect a temperature of the first heat conductive sheet 530 in the second bar-shaped hole. The control method further comprises the following steps: step A: the temperature of the corresponding first heat-conductive sheet 530 is detected by each temperature sensor. And B: according to the temperature of each first heat-conducting fin 530, the power value of the corresponding first semiconductor cooling fin 510 is controlled so that the difference between the temperatures of any two first heat-conducting fins 530 is within a preset range.

In this embodiment, the working power of each first semiconductor cooling plate 510 is different, so as to perform reasonable heat dissipation on the motor. Through the operating power value of control first semiconductor refrigeration piece 510 promptly, make the heat dissipation of motor and the heating of motor reach effective reasonable unity, make full use of different heat dissipation power's first semiconductor refrigeration piece 510 guarantees the radiating rationality of motor, the place heat dissipation that the heat is many promptly is fast, the place heat dissipation that the heat is few is slow, reach the heat dissipation and the unity that generates heat, and then the temperature that can make every position department of motor tends to unanimity to guarantee the performance of motor. The preset range is preferably 0 ℃ to 3 ℃.

In some embodiments of the present invention, step a is preceded by step C: when the motor is started every time and the time interval of the motor starting distance and the last time of motor closing is greater than the preset time interval, detecting the environment temperature of the motor, and controlling the first semiconductor refrigerating sheet 510 to be started according to the environment temperature; for example, the delayed turn-on time of the first semiconductor chilling plate 510 is determined according to the ambient temperature, and the turn-on of the first semiconductor chilling plate 510 is controlled according to the delayed turn-on time. Otherwise, when the motor is turned on, the first semiconductor cooling fins 510 are turned on at the same time. The embodiment of the invention fully considers the working environment of the motor, and the first semiconductor refrigeration sheet 510 is started in a delayed and long time in a cold place, thereby saving resources. In a hot place or in a case where the two-time power-on time is short, the first semiconductor cooling sheet 510 is turned on as early as possible to perform sufficient and effective heat dissipation. Preferably, the preset time interval is 2h to 4h, preferably 2.5h, 3h, etc.

Further, step D is included after step B: the first semiconductor cooling fins 510 are turned off after the stator and rotor of the motor are turned off for a preset time. And the preset time is 10min to 15 min. After the motor is closed, the motor can be quickly cooled to a normal temperature state, the motor is protected, and overheating loss of the motor is prevented.

Further, when the external heat sink 520 includes a plurality of second semiconductor chilling plates, the second semiconductor chilling plates are turned on in synchronization with the first semiconductor chilling plates 510; the power values of the plurality of second semiconductor chilling plates are the same. When the external heat sink 520 includes a third semiconductor cooling fin. The third semiconductor chilling plate and the first semiconductor chilling plate 510 are synchronously opened.

In some preferred embodiments of the present invention, when the external heat sink 520 includes a plurality of second semiconductor chilling plates, the second semiconductor chilling plates are turned on in synchronization with the first semiconductor chilling plates 510. And the power of each second semiconductor chilling plate can be adapted to the power of the corresponding first semiconductor chilling plate 510. For example, it may be 1.02 times to 1.05 times the sum of the powers of the two first semiconductor cooling fins 510 thermally connected to the second semiconductor cooling fin.

Thus, it should be appreciated by those skilled in the art that while a number of exemplary embodiments of the invention have been illustrated and described in detail herein, many other variations or modifications consistent with the principles of the invention may be directly determined or derived from the disclosure of the present invention without departing from the spirit and scope of the invention. Accordingly, the scope of the invention should be understood and interpreted to cover all such other variations or modifications.

Claims

1. An electric machine comprising a housing, a stator and a rotor; the stator is arranged in the shell; the rotor is arranged on the radial inner side of the stator; the shell is provided with a rear end cover, and a shaft end groove is formed in the rear end cover; the rotor is provided with an output shaft, and the rear end of the output shaft is inserted into the shaft end groove; characterized in that, the motor still includes:

a play detection device configured to detect a displacement between a real-time position and an initial position of the output shaft to control the primary in accordance with the displacement to thereby keep the output shaft at the initial position; and the rotor further comprises:

a rotor core mounted to the outer cylindrical portion; and

2. The electric machine of claim 1,

the secondary is a permanent magnet and is mounted on the output shaft.

3. The electric machine of claim 1,

and a coil groove is formed in the peripheral wall of the shaft end groove, and the primary winding coil is arranged in the coil groove.

4. The electric machine of claim 1,

the shell is provided with a front end cover, and the front end cover is provided with a shaft hole;

5. The electric machine of claim 1,

the damping structure is a damping pad or a plurality of compression springs uniformly distributed on the first rolling bearing.

6. The electric machine of claim 1, wherein the connection bracket comprises:

a fixing ring to which an outer ring of the second rolling bearing is attached;

7. The electric machine of claim 6, wherein each said web has:

8. The electric machine according to claim 1, wherein the stator further has a plurality of heat dissipation hole groups, each of the heat dissipation hole groups having two first bar-shaped holes provided on both sides of a stator slot of a corresponding one of the stators, each of the first bar-shaped holes extending in an axial direction of the stator and opening radially outward of the stator;

The motor further includes:

9. A control method for an electric machine according to any one of claims 1 to 8, characterized by comprising: