CN115833515A

CN115833515A - High-precision matching structure of linear Hall and induction magnet ring for brushless motor

Info

Publication number: CN115833515A
Application number: CN202211612911.0A
Authority: CN
Inventors: 吴凌云; 吴小康; 杜姗; 张玉琦; 王�锋
Original assignee: Zhejiang Linix Motor Co Ltd
Current assignee: Zhejiang Linix Motor Co Ltd
Priority date: 2022-12-15
Filing date: 2022-12-15
Publication date: 2023-03-21

Abstract

The invention relates to a brushless motor, in particular to a high-precision matching structure of a linear Hall and an induction magnet ring for the brushless motor. The linear Hall and induction magnetic ring high-precision matching structure for the brushless motor comprises an induction magnetic ring fixed with a rotor and a Hall fixed with a stator, wherein the rotor comprises a rotor core and a rotor shaft, the stator comprises a machine shell and a stator core, a positioning sleeve is fixed to the axial side of the rotor core, a positioning structure which is matched with the rotor core and enables the rotor core and the positioning sleeve to be coaxial is arranged between the rotor core and the positioning sleeve, the induction magnetic ring is sleeved and fixed on the positioning sleeve, the inner wall of the positioning sleeve is not in contact with the outer wall of the rotor shaft, and the Hall is fixed on the stator core. The invention has the advantages that the installation precision of the induction magnetic ring and the Hall can be improved, thereby realizing high matching precision between the linear Hall and the induction magnetic ring and being convenient for realizing sine wave driving.

Description

High-precision matching structure of linear Hall and induction magnet ring for brushless motor

Technical Field

The invention relates to a brushless motor, in particular to a high-precision matching structure of a linear Hall and an induction magnet ring for the brushless motor.

Background

The sine wave drive has a high requirement on the consistency of the Hall output level, so that the requirement on the uniformity of the magnetic field distribution is high, the induction magnetic ring and the main magnet on the rotor core need to be separately magnetized, the polarity alignment between the induction magnetic ring and the main magnet needs to be ensured, and the high matching precision between the Hall and the induction magnetic ring is ensured. However, the matching precision between the hall and the induction magnetic ring of the existing brushless motor is low, and the existing brushless motor can only adopt a switch type hall and cannot adopt a linear type hall, so that the service performance of the motor can not meet the requirement.

Among the prior art, hall is located rear end cap department usually, and hall fixes on the circuit board, and the circuit board passes through the casing or the rear end cap of screw and stator fixed, and screw hole clearance are great, can lead to hall's mounted position skew 2, and the installation is accurate relatively poor, can lead to motor rotor to advance or lag the switching-over, still can lead to motor vibrations noise increase, and response speed is slow, and the condition that the maximum efficiency is low takes place, still can lead to the condition emergence that unable accurate vector control so that can't realize the brushless motor function even.

The patent with publication number CN211377855U discloses a sine wave driven brushless motor, which comprises a stator assembly and a rotor assembly, wherein a circuit board is fixed on a stator of the stator assembly, the circuit board is provided with a central hole for a rotating shaft of the rotor assembly to pass through, and a plurality of linear hall are fixed on the circuit board; be fixed with stator skeleton on the stator, stator skeleton is equipped with the protruding and first locating groove of first location of mutually supporting with the circuit board, circuit board inner edge department is fixed with the hall mounting bracket, the hall mounting bracket is located circuit board axial side, be formed with the mounting groove that is used for the fixed hall in location on the hall mounting bracket, be equipped with a plurality of through-holes that supply hall pin to pass through on the axial face that the hall mounting bracket is close to the circuit board, the through-hole axial run through the hall mounting bracket and with the mounting groove intercommunication, hall's pin passes behind the through-hole and welds with the circuit board.

Above-mentioned scheme makes the circuit board location on the stator, further fixes a position hall through the mounting groove of hall mounting bracket again, through the fashioned location fit of mould to improve hall's installation accuracy, in order to be applicable to linear type hall, but still need further improve induction magnet ring's cooperation accuracy.

The patent publication No. CN104617731A discloses an assembly structure of an induction magnetic ring and a rotor shaft of a motor rotor, the motor is a permanent magnet brushless dc motor, the assembly structure of the induction magnetic ring and the rotor shaft of the permanent magnet brushless dc motor rotor comprises a rotor shaft, a rotor core, a main magnet, a plastic bushing and an induction magnetic ring, the main magnet is sleeved and fixed outside the rotor core, both sides of the plastic bushing are respectively provided with a raised head, the induction magnetic ring and the rotor core are respectively provided with a connecting hole matched with the raised head, the plastic bushing is arranged between the rotor core and the induction magnetic ring, the induction magnetic ring comprises an induction magnetic ring main body and a lining copper sleeve, the lining copper sleeve is arranged inside a central hole of the induction magnetic ring main body, the induction magnetic ring main body and the lining copper sleeve are in close fit connection, and the lining copper sleeve and the rotor shaft are in clearance fit. In order to reduce the contact area between the lining copper sleeve and the rotor shaft, the lining copper sleeve is step-shaped so as to form a clearance with the rotor shaft.

In the above scheme, the clearance is arranged so that the induction magnet ring main body deviates from the assembly position of the lining copper sleeve and the rotor shaft, the assembly and magnetizing precision of the induction magnet ring are improved by arranging the step structure, but in order to ensure that the axial length of the motor is smaller, the clearance is still closer to the induction magnet ring main body, so that the coaxiality between the induction magnet ring main body and the main magnet is poorer, and the defects of nonuniform distribution of magnetic lines of force and small magnetic flux of the induction magnet ring still exist. And the induction magnetic ring main body and the lining copper sleeve, and the lining copper sleeve and the rotor shaft are tightly matched, and parts can deform to a certain extent after being pressed and installed. In the scheme, in order to charge magnetism together, the outer diameter of the main body of the induction magnetic ring is the same as or close to that of the main magnet, so that the size of the main body of the induction magnetic ring is larger; and the power density of the inductive magnetic ring main body and the main magnet which are simultaneously magnetized is relatively low, so that sine wave driving can not be realized.

Disclosure of Invention

The invention aims to provide a high-precision matching structure of a linear Hall and an induction magnetic ring for a brushless motor, which can improve the installation precision of the induction magnetic ring, thereby realizing high matching precision between the linear Hall and the induction magnetic ring and facilitating the realization of sine wave driving.

In order to achieve the purpose, the invention adopts the following technical scheme: the linear Hall and induction magnetic ring high-precision matching structure for the brushless motor comprises an induction magnetic ring fixed with a rotor and a Hall fixed with a stator, wherein the rotor comprises a rotor core and a rotor shaft, the stator comprises a machine shell and a stator core, a positioning sleeve is fixed to the axial side of the rotor core, a positioning structure which is matched with the rotor core and enables the rotor core and the positioning sleeve to be coaxial is arranged between the rotor core and the positioning sleeve, the induction magnetic ring is sleeved and fixed on the positioning sleeve, the inner wall of the positioning sleeve is not in contact with the outer wall of the rotor shaft, and the Hall is fixed on the stator core.

The induction magnetic ring is arranged on the positioning sleeve, the positioning sleeve is not tightly matched with the rotor shaft, the positioning sleeve cannot cause the position deviation of the induction magnetic ring due to press-fitting deformation, the installation precision of the induction magnetic ring is higher, the high-precision fixation of the linear Hall is convenient to realize, the performance of the brushless motor can be ensured, and the sine wave drive is convenient to realize. The positioning sleeve can be fixed with the rotor core through tight fit at the positioning structure. In order to realize sine wave conveniently, the rotor core can be provided with magnetic shoes in a ring shape, so that the magnetic shoes and the induction magnetic ring are magnetized separately, and the positioning between the rotor core and the induction magnetic ring is realized through the positioning structure, so that the induction magnetic ring is prevented from generating angle deviation after being assembled, and the assembly precision is improved; the magnetic energy is separately charged, so that the magnetic force lines of the induction magnetic ring are distributed more uniformly, and the larger magnetic flux can be ensured. When the rotor core is provided with the magnetic shoes, the induction magnetic ring can be made smaller, so that the material is saved, and the contact between the induction magnetic ring and parts such as the stator winding and a circuit board can be avoided.

Preferably, the positioning structure comprises a positioning hole formed in the rotor core and a positioning protrusion formed in the positioning sleeve, and the plurality of iron core punching sheets of the rotor core are provided with the positioning hole which penetrates through the positioning hole in the axial direction. The positioning protrusions can be in clearance fit in the positioning holes or in close fit in the positioning holes, the positioning holes of the rotor core and the positioning protrusions of the positioning sleeves are formed by molds, positioning accuracy is higher, the offset angle of the assembled induction magnetic ring is not more than 0.1 degrees, and using effect is further improved.

Preferably, the rotor core is provided with at least three uniformly distributed positioning holes, the positioning sleeve is provided with a first ring portion close to the rotor core, the first ring portion is provided with positioning portions which extend to the circumferential outer side and are uniformly distributed, the number of the positioning portions is the same as that of the positioning holes, and the axial face of each positioning portion is provided with the positioning protrusions. Even the protruding tight fit of location is in the locating hole, certain deformation can take place for the protruding department of location, and the influence that its brought also can only be used in location portion department, and can not be used in first ring portion itself and respond to magnetic ring department even to further improve response magnetic ring's the precision of setting up.

Preferably, the induction magnetic ring is a plastic magnet, and the induction magnetic ring and the positioning sleeve are formed by injection molding. The induction magnetic ring is integrally arranged on the positioning sleeve, the induction magnetic ring and the positioning sleeve do not need to be tightly matched, the assembly procedures can be reduced, and the negative influence caused by the assembly between the induction magnetic ring and the positioning sleeve is avoided.

Preferably, the rotor shaft is rotatably fixed to the housing by a bearing, and the positioning sleeve is confined between the rotor core and the bearing. The positioning sleeve is axially limited through the bearing, the positioning sleeve does not need to be tightly matched with the rotating shaft, and deformation does not occur, so that the fixing precision of the induction magnetic ring is improved.

Preferably, the locating sleeve comprises a second ring portion located on the axial side of the induction magnet ring and far away from the rotor core, and the second ring portion is used for being in contact with the bearing. The bearing is prevented from directly contacting the induction magnetic ring, and the position deviation of the induction magnetic ring caused by the deformation of the positioning sleeve after being pressed by the bearing is avoided.

Preferably, be equipped with stator framework on the stator core, stator framework has the skeleton cooperation portion that stretches into in every stator core's the tooth's socket, skeleton cooperation portion surface pastes with tooth's socket groove face mutually, be equipped with the constant head tank to axial side open-ended on the stator framework, hall's casing is located in the constant head tank, the groove face of constant head tank including the first groove face that has the elastic component and be used for with the second groove face of hall's casing contact location, when hall's casing inserts in the constant head tank, the elastic component offsets and makes the casing with casing one side second groove face contact. Through setting up the elastic component that elasticity is less to make hall's casing can effectively with the contact of second groove face, can ensure to avoid hall casing to warp under the condition of hall position, also need not adopt modes such as glue is fixed, clearance fit to realize the location of linear type hall fixed, further improve the fixed precision of linear type hall. By the mode, the offset angle after the Hall is installed is not more than 0.1 degrees, the vector control effect can be improved, and the efficiency of the maximum torque current is improved by 2 percent compared with that of the control motor.

Preferably, the second groove surface comprises two oppositely arranged inclined surfaces, the two inclined surfaces form a V-shaped included angle, the opening of the V-shaped included angle faces the first groove surface, and the shell is provided with two oppositely arranged contact surfaces used for being matched with the inclined surfaces. After the shell of the Hall is partially inserted into the positioning groove, the two inclined planes of the second groove surface form a V-shaped clamping angle, the shell of the Hall is also provided with a contact surface matched with the inclined planes, and the contact surface and the inclined planes of the second groove surface form a guide, so that the installation position of the Hall can be further adjusted, and the installation precision is further improved.

Preferably, the elastic piece is an elastic raised line with one end connected with the first groove surface and the other end close to the second groove surface, and the end part of the elastic raised line connected with the first groove surface is closer to the axial opening of the positioning groove than the other end. The above-mentioned setting of elasticity sand grip both is convenient for hall shell's insertion, the setting and the injection moulding of the constant head tank of also being convenient for.

Preferably, the first groove surface is provided with an inwards concave avoiding groove. The avoidance groove is arranged to reduce the contact area between the shell of the Hall and the positioning groove, so that the Hall can be clamped into the positioning groove conveniently.

The invention has the advantages that the installation precision of the induction magnetic ring and the Hall can be improved, thereby realizing high matching precision between the linear Hall and the induction magnetic ring and being convenient for realizing sine wave driving.

Drawings

Fig. 1 is a schematic structural view of the hall sensor of the present invention in cooperation with an induction magnet ring.

Fig. 2 is a schematic structural view of a rotor of the present invention.

Fig. 3 is a cross-sectional view of a rotor of the present invention.

Fig. 4 is a schematic structural diagram of the positioning sleeve and the induction magnet ring of the present invention.

Fig. 5 is a schematic structural diagram of a hall bracket according to the present invention.

Fig. 6 is a sectional view at a location groove of the present invention.

Fig. 7 is an enlarged view of the hall bracket of fig. 5 at a detent.

Detailed Description

The invention is further described below with reference to the figures and specific embodiments.

As shown in fig. 1 to 4, the present embodiment discloses a high-precision matching structure of linear hall and induction magnet ring for a brushless motor, which includes an induction magnet ring 1 fixed with a rotor and three hall rings 2 fixed with a stator, wherein the induction magnet ring 1 is a plastic magnet, and the hall rings of the present embodiment are three linear hall rings.

The rotor includes rotor core 31 and

rotor shaft

32, 31 axial side of rotor core is fixed with

position sleeve

4, 31 circumference side equipartitions of rotor core have a plurality of tile shape main magnet 30, be equipped with between rotor core 31 and position sleeve 4 and mutually support so that rotor core 31 and the coaxial location structure of position sleeve 4,

induction magnet ring

1 and 4 injection moulding of position sleeve, 4 inner walls of position sleeve and 32 outer walls of rotor shaft contactless, hall 2 fixes on stator core 31.

The positioning structure comprises three uniformly distributed positioning holes 311 arranged on the rotor core 31 and three uniformly distributed positioning protrusions 411 arranged on the positioning sleeve 4, and a plurality of iron core punching sheets of the rotor core 31 are provided with positioning holes 311 which axially penetrate through. The positioning sleeve 4 sequentially comprises a first ring part 41, a third ring part 43 and a second ring part 42 along the axial direction, the induction magnetic ring 1 is sleeved on the third ring part 43, and the first ring part 41 is close to the rotor core 31. The first ring portion 41 is provided with positioning portions 410 extending to the circumferential outer side and uniformly distributed, the number of the positioning portions 410 is the same as that of the positioning holes, and the positioning protrusions 411 are arranged on the axial surface of the positioning portions 410. The second ring part 42 is located at the axial side of the induction magnet ring 1 and the third ring part 43, the rotor shaft 32 is rotationally fixed with the casing 100 through the bearing 33, the positioning sleeve 4 is limited between the rotor core 42 and the bearing 33, and the second ring part 42 is used for contacting with the bearing 33. The outer diameters of the first ring portion 41 and the second ring portion 42 are smaller than the outer diameter of the third ring portion 43, and the inner diameter of the induction magnetic ring 1 is larger than the outer diameter of the bearing 33.

As shown in fig. 1, 5, 6 and 7, the stator includes a housing 100 and a stator core (not shown), the stator core is provided with a stator frame, the stator frame has a frame fitting portion (not shown) extending into a tooth slot of each stator core (not shown), a surface of the frame fitting portion (not shown) is attached to a surface of the tooth slot, the stator frame is fixed with a hall bracket 6, the hall bracket 6 has a fitting slot 60 passing through, and the stator frame has a fitting protrusion 51 fitting in the fitting slot 60.

The hall support 6 is provided with a positioning groove 61 which is opened towards the axial direction, the shell of the hall 2 is positioned in the positioning groove 61, the hall support 6 is provided with a positioning boss 62 which is used for positioning a fixed circuit board (not shown in the figure), and the positioning boss 62 is provided with a threaded hole 621 which is used for fixing the circuit board. This embodiment is fixed hall 2 through constant head tank 61, and hall 2's extraction pin is fixed with the circuit board, but under hall 2's casing fixed position's the circumstances, even circuit board mounted position takes place the deviation, also only can cause the extraction pin crooked, can not lead to the place displacement of casing department that is used for with induction magnetic ring 1 complex hall 2.

The groove surface of the positioning groove 61 comprises a first groove surface 611 with an elastic element 610 and a second groove surface 612 for contact positioning with the housing of the hall 2, the second groove surface 612 comprises two oppositely arranged inclined surfaces, the two inclined surfaces form a V-shaped included angle, the opening of the V-shaped included angle faces the first groove surface 611, and the housing of the hall 2 also comprises two oppositely arranged contact surfaces for matching with the inclined surfaces. The elastic element 610 is an elastic raised strip with one end connected to the first groove surface 611 and the other end close to the second groove surface 612, and the end part of the elastic raised strip connected to the first groove surface is closer to the axial opening of the positioning groove than the other end; that is, when the hall 2 moves from top to bottom into the positioning groove 61, the end of the elastic element 610 connected to the first groove surface is the upper end, and along with the continuous movement of the hall 2, the elastic element 610 abuts against one side of the housing of the hall 2 and makes the contact surface of the housing contact with the second groove surface 612.

In order to improve the positioning effect of the hall, the side surface of the end of the elastic element 610 away from the first slot surface includes a positioning plane 6101, and the extending direction of the positioning plane 6101 is parallel to the extending direction of the rotor shaft 32. In order to facilitate the manufacturing and demolding and the insertion of the hall 2, the first groove surface 611 is recessed to form an avoiding groove 614 which semi-surrounds the elastic member 610, a demolding opening 613 is formed at the groove bottom of the positioning groove 61, and the avoiding groove 614 is communicated with the demolding opening 613.

Claims

1. The utility model provides a brushless motor is with linear type hall and response magnetic ring high accuracy cooperation structure, includes the response magnetic ring fixed with the rotor and with the fixed hall of stator, the rotor includes rotor core and rotor shaft, the stator includes casing and stator core, its characterized in that: the rotor comprises a rotor core and is characterized in that a positioning sleeve is fixed on the axial side of the rotor core, a positioning structure which is matched with the rotor core to enable the rotor core and the positioning sleeve to be coaxial is arranged between the rotor core and the positioning sleeve, the induction magnetic ring is sleeved and fixed on the positioning sleeve, the inner wall of the positioning sleeve is not in contact with the outer wall of the rotor shaft, and the Hall is fixed on a stator core.

2. The linear hall and induction magnetic ring high-precision matching structure for the brushless motor as claimed in claim 1, wherein: the positioning structure comprises positioning holes formed in the rotor core and positioning protrusions arranged on the positioning sleeves, and a plurality of iron core punching sheets of the rotor core are provided with the positioning holes which axially penetrate through the iron core punching sheets.

3. The linear hall and induction magnetic ring high-precision matching structure for the brushless motor as claimed in claim 1, wherein: the rotor core is provided with at least three uniformly distributed positioning holes, the positioning sleeve is provided with a first ring portion close to the rotor core, the first ring portion is provided with positioning portions extending towards the outer side in the circumferential direction and uniformly distributed, the number of the positioning portions is the same as that of the positioning holes, and the axial face of each positioning portion is provided with the positioning protrusions.

4. The linear hall and induction magnet ring high-precision matching structure for the brushless motor according to claim 1, 2 or 3, characterized in that: the induction magnetic ring is a plastic magnet, and the induction magnetic ring and the positioning sleeve are formed in an injection molding mode.

5. The linear hall and induction magnet ring high-precision matching structure for the brushless motor as claimed in claim 1, 2 or 3, wherein: the rotor shaft is rotationally fixed with the machine shell through a bearing, and the positioning sleeve is limited between the rotor iron core and the bearing.

6. The linear hall and induction magnetic ring high-precision matching structure for the brushless motor as claimed in claim 5, wherein: the locating sleeve comprises a second ring portion which is located on the axial side of the induction magnetic ring and far away from the rotor core, and the second ring portion is used for being in contact with the bearing.

7. The linear hall and induction magnet ring high-precision matching structure for the brushless motor according to claim 1, 2 or 3, characterized in that: be equipped with stator framework on the stator core, stator framework has the skeleton cooperation portion that stretches into in every stator core's the tooth's socket, skeleton cooperation portion surface pastes with tooth's socket groove face mutually, be equipped with on the stator framework to axial side open-ended constant head tank, hall's casing is located in the constant head tank, the groove face of constant head tank including the first groove face that has the elastic component and be used for with the second groove face of hall's casing contact location, when hall's casing inserts in the constant head tank, the elastic component offsets and makes the casing with casing one side second groove face contact.

8. The linear hall and induction magnetic ring high-precision matching structure for the brushless motor as claimed in claim 7, wherein: the second groove surface comprises two oppositely arranged inclined surfaces, the two inclined surfaces form a V-shaped included angle, an opening of the V-shaped included angle faces the first groove surface, and the shell is provided with two oppositely arranged contact surfaces which are used for being matched with the inclined surfaces.

9. The linear hall and induction magnetic ring high-precision matching structure for the brushless motor as claimed in claim 7, wherein: the elastic piece is the elastic raised line that first trough surface is connected to one end, and the other end is close to the second trough surface, the axial opening part that the tip of first trough surface is more close to the constant head tank than the other end is connected to the elastic raised line.

10. The linear hall and induction magnetic ring high-precision matching structure for the brushless motor as claimed in claim 7, wherein: the first groove surface is provided with an inwards concave avoiding groove.