阅读说明：本技术 一种具有齿轮保护机构的电动自行车轮毂电机 (Electric bicycle hub motor with gear protection mechanism ) 是由 眭华兴 于 2020-07-09 设计创作，主要内容包括：本发明公开了一种具有齿轮保护机构的电动自行车轮毂电机,包括主轴、轮毂、左端盖和右端盖、电机和行星齿轮减速机构,电机为有定子铁芯的轴向磁场电机,包括一转子组件和一定子组件,转子组件通过包含有角接触球轴承的具有并列的滚动体的轴承单元与所述主轴转动连接,定子组件与所述主轴固定连接,行星齿轮减速机构的外齿圈设传力齿,轮毂或左端盖上设受力齿,传力齿与受力齿之间设弹簧,电动自行车起动/刹车时,弹簧溃缩变形,从而保护齿轮免遭冲击损坏。本发明成本低效率高,能大幅提高电动自行车的续行里程。(The invention discloses an electric bicycle hub motor with a gear protection mechanism, which comprises a main shaft, a hub, a left end cover, a right end cover, a motor and a planetary gear reduction mechanism, wherein the motor is an axial magnetic field motor with a stator core, the motor comprises a rotor assembly and a stator assembly, the rotor assembly is rotationally connected with the main shaft through a bearing unit which comprises angular contact ball bearings and is provided with parallel rolling bodies, the stator assembly is fixedly connected with the main shaft, an outer gear ring of the planetary gear reduction mechanism is provided with force transmission teeth, the hub or the left end cover is provided with force transmission teeth, a spring is arranged between the force transmission teeth and the force transmission teeth, and the spring collapses and deforms when an electric bicycle is started or braked, so that the gear is protected from impact damage. The invention has low cost and high efficiency, and can greatly improve the continuous mileage of the electric bicycle.)

1. The utility model provides an electric bicycle wheel hub motor with gear protection mechanism, includes main shaft, wheel hub, left end lid and right-hand member lid, motor and planetary gear reduction mechanism, planetary gear reduction mechanism includes planet carrier, outer ring gear, sun gear ring gear and planetary gear, the motor is through installing on the motor sun gear ring gear, by planetary gear reduction mechanism drives wheel hub rotates characterized by: the motor is an axial magnetic field motor with a stator core, and comprises a rotor assembly and a stator assembly, wherein the rotor assembly is rotationally connected with the main shaft through a bearing unit which comprises an angular contact ball bearing and is provided with parallel rolling bodies, the stator assembly is fixedly connected with the main shaft, the axial magnetic field motor also comprises a plurality of force transmission teeth, a plurality of stress teeth and a plurality of springs, the force transmission teeth are arranged on the outer circular surface of the outer gear ring or the circular surface on one side of a left end cover, the stress teeth are arranged on the inner circular surface of the hub or the inner side surface of the left end cover in a matching way of matching with the force transmission teeth, the outer gear ring with the force transmission teeth is movably sleeved with the inner surface of the hub, the springs are arranged between the force transmission teeth and the stress teeth, the power of the motor acts on the springs through the planetary gear speed reducing, when the electric bicycle is started or braked, the spring generates collapse deformation, so that the gear of the planetary gear speed reducing mechanism is prevented from being damaged by impact.

2. The electric bicycle hub motor with gear protection mechanism of claim 1, wherein the bearing unit is a double row angular contact ball bearing, or a series combination of a deep groove ball bearing and a single row angular contact ball bearing, or a series combination of two single row angular contact ball bearings.

3. The electric bicycle hub motor with gear protection mechanism according to claim 1, wherein the rotor assembly comprises a rotor disc and a plurality of permanent magnets arranged in a circumferential array on one side of the rotor disc on the stator assembly, and the other side of the rotor disc is fixedly connected with the sun gear ring.

4. The hub motor for electric bicycle with gear protection mechanism according to claim 1, wherein the stator assembly comprises a plurality of stator cores, a plurality of coils, a stator yoke and a stator tray, the stator core is formed by laminating a plurality of sheets of silicon steel material with different widths along a radial direction, the stator yoke is formed by laminating a plurality of disc sheets of silicon steel material along an axial direction, the stator core is connected with the stator yoke or with the stator yoke and the stator tray in a tenon-and-mortise structure, and the stator tray is fixedly connected with the main shaft.

5. The hub motor for electric bicycle with gear protection mechanism as claimed in claim 4, wherein the stator core has at least one first mortise on the radial overlapping surface perpendicular to the rotation surface of the rotor assembly away from one end of the rotor assembly, the first mortise is a "U" shaped slot, the stator yoke disc has a second mortise connected to the stator core and arranged in a circumferential array, the stator tray has a radial tray at the end away from the rotor disc, the radial tray has a third mortise connected to the stator core and corresponding to the second mortise, the solid portion of the first mortise section of the stator core is located in the second mortise and the third mortise, and the first mortise clamps the slot edge of the second mortise and the third mortise.

6. The hub motor for electric bicycle with gear protection mechanism according to claim 4, wherein the stator core has at least one first mortise on a radial overlapping surface perpendicular to a rotation surface of the rotor assembly away from one end of the rotor assembly, the first mortise is a "U" shaped slot, the stator yoke disc has second mortises connected to the stator core and arranged in a circumferential array, a first connecting hole is further formed on a near-axis side of the stator yoke disc, the stator tray has a radial tray, a second connecting hole corresponding to the first connecting hole is formed on the radial tray, and the stator yoke disc and the stator tray are riveted or bolted through the first connecting hole and the second connecting hole; the solid part of the first mortise interval of the stator core is positioned in the second mortise, and the slot edge of the second mortise is clamped in the first mortise.

7. The electric bicycle hub motor with gear protection mechanism according to claim 5 or 6, wherein the second mortise and the third mortise are open slots, and the solid portion of the first mortise section of the stator core is inserted into the second mortise or the second mortise and the third mortise from the opening, so that the stator core is in mortise and tenon connection with the stator yoke disc or the stator yoke disc and the stator tray.

8. The hub motor for electric bicycle with gear protection mechanism according to claim 4, wherein the stator core has at least one first mortise on a radial overlapping surface perpendicular to a rotation surface of the rotor assembly away from one end of the rotor assembly, the first mortise is an "L" shaped slot, the stator yoke disc has second mortises connected to the stator core and arranged in a circumferential array, a first connecting hole is further formed on a near-axis side of the stator yoke disc, the stator tray has a radial tray, a second connecting hole corresponding to the first connecting hole is formed on the radial tray, and the stator yoke disc and the stator tray are riveted or bolted through the first connecting hole and the second connecting hole; and the solid part of the first mortise interval of the stator core is inserted into the second mortise, and the stator core is fixed with the stator yoke disc in a welding mode.

9. The hub motor for electric bicycle with gear protection mechanism according to claim 1, further comprising a retaining ring or a retaining ring and a retaining ring, wherein the retaining ring is disposed on the inner circumferential surface of the hub and serves as an axial stop for the outer gear ring or the outer gear ring and the spring, and the retaining ring is fixedly mounted on the force-receiving teeth on the left end cap and serves as an axial stop for the spring.

Technical Field

The invention relates to the technical field of hub motors of electric bicycles, in particular to a hub motor of an electric bicycle with an axial magnetic field of a gear protection mechanism.

Background

The existing electric bicycles are provided with gear hub motors, such as Chinese patents CN03127256.8 and CN201510104597.9 of a through-shaft structure outer rotor motor, and also such as U.S. patent US20050176542A1 of a half-shaft structure inner rotor motor, the driving motors of the gear hub motors are all direct current permanent magnet motors with radial magnetic fields, the high-efficiency sections of the types are deviated to the high-power sections, the driving motors usually run in the low-efficiency sections when the vehicle normally runs, and the running mileage is short; the axial magnetic field motor without the iron core, which has a wide range of efficiency platform intervals and can greatly improve the continuous mileage, has a gear hub motor, needs to consume more rare earth permanent magnets, has obvious insufficient economy, adopts the axial magnetic field motor with the stator iron core wound by silicon steel sheet continuous punching sheets, has low manufacturing efficiency and high cost of the stator iron core, can only be manually completed at present, and has high volume production cost. The gear hub motor with the gear is in a structural form of a planetary gear speed reducing mechanism, the planetary gear is made of polymer materials such as nylon or polyformaldehyde which are good in wear resistance and have self-lubricating performance, when an electric bicycle starts or brakes, the gear of the speed reducing mechanism bears large impact force, broken teeth can occur on the planetary gear which is low in structural strength, the phenomenon is easier to occur in cold winter, and the market acceptance is not high.

Disclosure of Invention

The invention aims to provide a hub motor with a gear protection mechanism, which meets the requirements of GB 17761-2018 safety technical Specification of electric bicycles, and the hub motor with the gear protection mechanism is applied to the field of electric bicycles with excellent performance at low cost under the existing production technical conditions, so that the long-acting stable operation of the hub motor is ensured, and the requirement of people on the increase of the driving mileage is met.

The technical idea is as follows: under the existing production technical conditions, the technical scheme of 'stator core of independent module + stator yoke disc + concentrated coil winding' is adopted to realize the high-efficiency low-cost batch production of the stator core assembly; the planetary gear speed reducing mechanism is flexibly connected with the hub or the end cover, the impact on the gear is reduced by utilizing the function of spring crumple energy absorption, the geared hub motor is maintenance-free in the service life cycle of the electric bicycle, and the initial cost of the hub motor is equal to that of the hub motor in the prior art.

Therefore, the invention provides the following scheme:

the invention discloses an electric bicycle hub motor with a gear protection mechanism, which comprises a main shaft, a hub, a left end cover, a right end cover, a motor and a planetary gear reduction mechanism, wherein the hub is detachably and fixedly connected with the left end cover; the motor is an axial magnetic field motor with a stator core, and comprises a rotor assembly and a stator assembly, wherein the rotor assembly is rotationally connected with the main shaft through a bearing unit which comprises an angular contact ball bearing and is provided with parallel rolling bodies, the stator assembly is fixedly connected with the main shaft, the axial magnetic field motor also comprises a plurality of force transmission teeth, a plurality of stress teeth and a plurality of springs, the force transmission teeth are arranged on the outer circular surface of the outer gear ring or on the circular surface of the outer gear ring on one side of the left end cover, the stress teeth are arranged on the inner circular surface of the hub or the inner side surface of the left end cover in a matching way of the force transmission teeth, the outer gear ring with the force transmission teeth is movably sleeved with the inner surface of the hub, the springs are arranged between the force transmission teeth and the stress teeth, and the power of the motor acts on the springs through the, and then transmitted to the hub, and the spring is collapsed and deformed when the electric bicycle is started or braked, so that the gear of the planetary gear speed reducing mechanism is prevented from being damaged by impact.

Preferably, the bearing unit is a double-row angular contact ball bearing, or a series combination of a deep groove ball bearing and a single-row angular contact ball bearing, or a series combination of two single-row angular contact ball bearings.

Preferably, the rotor assembly comprises a rotor disc and a plurality of permanent magnets arranged in a circumferential array on one side of the rotor disc positioned on the stator assembly, and the other side of the rotor disc is fixedly connected with the sun gear ring.

Preferably, the stator assembly comprises a plurality of stator cores, a plurality of coils, a stator yoke disc and a stator tray, the stator cores are formed by laminating a plurality of thin sheets of silicon steel materials with different widths along the radial direction, at least one first mortise with the width of 0-5 mm is arranged on a radial laminating surface, far away from one end of the rotor assembly, perpendicular to the rotating surface of the rotor assembly, of the stator core, a pole shoe is arranged at one end close to the rotor assembly, and the first mortise is a radial slot; the stator yoke dish forms for the disc thin slice of a plurality of silicon steel materials along the axial direction coincide, perhaps the stator yoke dish forms for the disc thin slice of a plurality of silicon steel materials and the reinforcement disc piece of non-silicon steel materials along the axial direction coincide, reinforcement disc piece is used for the reinforcing the tensile ability of axial magnetism is overcome to the stator yoke dish, reinforcement ring piece stacks and keeps away from at the stator yoke dish one side of rotor subassembly, the stator yoke dish cover is established on the stator tray, stator core with the stator yoke dish or with the stator yoke dish with the stator tray is with mortise-tenon joint structure, the stator tray with main shaft fixed connection.

Preferably, the coil in the stator assembly is sleeved between the pole shoe of the stator core and the first mortise, and the coil and the stator core are insulated and blocked by an insulated coil skeleton or by coating an insulating material on the stator core.

Preferably, the first tongue-and-groove is a "U" shaped groove, the stator yoke disc is provided with a second tongue-and-groove connected in a circumferential array arrangement, the stator tray is far away from one end of the rotor disc and is provided with a radial tray, the radial tray is provided with a third tongue-and-groove connected with the stator core and corresponding to the second tongue-and-groove, the groove shape of the second tongue-and-groove and the groove shape of the third tongue-and-groove correspond to and are consistent with the entity part of the first tongue-and-groove interval of the stator core, the groove width of the first tongue-and-groove is consistent with the sum of the axial lengths of the stator yoke disc and the stator tray, the entity part of the first tongue-and-groove interval of the stator core is located in the second tongue-and-groove and in the third tongue-and groove, and the groove edge of the second tongue-and-groove is clamped in the first tongue.

Preferably, the first mortise is a "U" shaped slot, the stator yoke disc is provided with second mortises arranged in a circumferential array and connected with the stator core, a first connecting hole is further formed in the side close to the shaft of the stator yoke disc, a radial tray is arranged at one end, close to the rotor disc, of the stator tray, a second connecting hole corresponding to the first connecting hole is formed in the radial tray, and the stator yoke disc and the stator tray are riveted or bolted through the first connecting hole and the second connecting hole; the groove shape of the second tongue-and-groove corresponds to and is consistent with the entity part of the first tongue-and-groove interval of the stator core, the groove width of the first tongue-and-groove is consistent with the axial length of the stator yoke disc, the entity part of the first tongue-and-groove interval of the stator core is located in the second tongue-and-groove, and the groove edge of the second tongue-and-groove is clamped in the first tongue-and-groove.

Preferably, the second mortise and the third mortise are open slots, and the solid part of the stator core between the first mortise and the first mortise is inserted into the second mortise or the second mortise and the third mortise from the opening, so that the stator core is connected with the stator yoke disc or the stator yoke disc and the stator tray in a mortise and tenon structure.

Preferably, the first mortise is an "L" shaped slot, the stator yoke disc is provided with second mortises arranged in a circumferential array and connected with the stator core, a first connecting hole is further formed in the side close to the shaft of the stator yoke disc, a radial tray is arranged at one end, close to the rotor disc, of the stator tray, a second connecting hole corresponding to the first connecting hole is formed in the radial tray, and the stator yoke disc and the stator tray are riveted or bolted through the first connecting hole and the second connecting hole; and the solid part of the first mortise interval of the stator core is inserted into the second mortise, and the stator core is fixed with the stator yoke disc in a welding mode.

Preferably, the bearing stator further comprises a retaining ring or a retaining ring and a retaining ring, the retaining ring is arranged on the inner circular surface of the hub and serves as an axial limiting stop of the outer gear ring or the outer gear ring and the spring, and the force-bearing teeth fixedly mounted on the left end cover are located on one surface of the stator assembly and serve as an axial limiting stop of the spring.

Preferably, the planetary gear reduction mechanism is a two-stage reduction structure, and the planetary gear of the planetary gear reduction mechanism is a duplicate gear.

Compared with the prior art, the invention has the following technical effects:

the axial magnetic field motor, especially the axial magnetic field motor with a single-stator and single-rotor fixed shaft structure and a stator core is applied to the hub motor of the electric bicycle, compared with the hub motor on the market, the consumption of three main materials of the motor, namely the permanent magnet, the silicon steel sheet and the copper enameled wire, is reduced to different degrees, the efficiency platform of the motor is wide, and the continuous mileage of the electric bicycle is greatly improved; all parts in the technical scheme of the invention can be produced in batch by using the existing equipment and process; in the invention, the force transmission teeth on the outer gear ring and the stressed teeth on the hub or the left end cover are integrally molded with the body connected with the outer gear ring, although the cost is slightly increased, the service life of the gear and the torque bearing capacity of the hub motor are greatly improved, and the problem of gear breakage in the industry which is puzzled for a long time is thoroughly solved.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings needed in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings without creative efforts.

FIG. 1 is a schematic structural diagram of an axial magnetic field hub motor with a gear protection mechanism according to this embodiment;

FIG. 2 is a schematic structural diagram of a gear protection mechanism according to the present embodiment;

FIG. 3 is a schematic view of a stator tray structure;

FIG. 4 is a schematic view of the connection of a stator core, a stator yoke disc and a stator tray;

FIG. 5 is a schematic view of the connection of a stator core, an alternative stator yoke disc and an alternative stator tray;

FIG. 6 is a left side view of a motor stator assembly structure;

FIG. 7 is a schematic view of a gear protection mechanism with stressed teeth on a hub;

FIG. 8 is a schematic view of a gear protection mechanism with stressed teeth on the left end cap;

FIG. 9 is a schematic view of a gear protection mechanism with force transmitting teeth on the torus of the outer gear ring;

FIG. 10 is a schematic view of a bearing unit;

fig. 11 is another structural schematic view of the bearing unit.

Description of reference numerals: 1, a main shaft; 2, a hub; 3, a left end cover; 4, a right end cover; 5 a planet carrier; 6, an outer gear ring; 7 sun gear ring gear; 8 a planetary gear; 9 a stator core; 10 rolling bodies; 11 force transmission teeth; 12 a force-bearing tooth; 13 a spring; 15 double-row angular contact ball bearings; 16 deep groove ball bearings; 17 single-row angular contact ball bearings; 18 a rotor disk; 19 a permanent magnet; 20 coils; 21 a stator yoke disc; 22 a stator tray; 23 a first mortise; 24 pole shoes; 25 reinforcing disk pieces; 26 air gaps; 27 a bobbin of a coil; 28 a second mortise; 29 a radial tray; 30 a third mortise; 31 a first connection hole; 32 a second connection hole; 33 a retainer ring; 34 stop ring.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

As shown in fig. 1-11, the hub motor of an electric bicycle with a gear protection mechanism of the present embodiment includes a main shaft 1, a hub 2, a left end cover 3 and a right end cover 4, a motor and a planetary gear reduction mechanism, wherein the hub of the hub 2 is detachably and fixedly connected to the left end cover 3, the motor and the planetary gear reduction mechanism are located in an inner space enclosed by the hub 2, the left end cover 3 and the right end cover 4, the planetary gear reduction mechanism includes a planet carrier 5, an outer ring gear 6, a sun gear ring gear 7 and a planetary gear 8, and the motor drives the hub 2 to rotate through the sun gear ring gear 7 mounted on the motor by the planetary gear reduction mechanism; the motor is an axial magnetic field motor comprising a stator core 9, and comprises a rotor assembly and a stator assembly, wherein the rotor assembly is rotationally connected with a main shaft 1 through a bearing unit which comprises an angular contact ball bearing and is provided with parallel rolling bodies 10, the stator assembly is fixedly connected with the main shaft 1, the axial magnetic field motor further comprises a plurality of force transmission teeth 11, a plurality of stress teeth 12 and a plurality of springs 13, the force transmission teeth 11 are arranged on the outer circular surface of an outer gear ring 6 or on the circular surface of the outer gear ring 6 positioned on one side of a left end cover 3, the stress teeth 12 are arranged on the inner circular surface of a hub 2 or the inner side surface of the left end cover 3 in a matching mode of matching with the force transmission teeth 11, the outer circular surface of the force transmission teeth 11 is movably sleeved with the inner surface of the hub 2, the inner circular surface of the stress teeth 12 is movably sleeved with the outer surface of the outer gear ring 6, further, the spring 13 is deformed by being crushed when the electric bicycle is started or braked, and the gear of the planetary gear speed reduction mechanism is prevented from being damaged by impact.

The skilled person can select the specific form of the bearing unit according to actual needs, as long as the bearing unit comprises an angular contact ball bearing capable of bearing axial magnetic pull, and the bearing unit has parallel rolling bodies 10 bearing overturning moment. For example, the bearing unit may be a double row angular contact ball bearing 15, as shown in fig. 10, or a series combination of a deep groove ball bearing 16 and a single row angular contact ball bearing 17, as shown in fig. 1, 11, or a series combination of two single row angular contact ball bearings 17.

The rotor assembly comprises a rotor disc 18 and a plurality of permanent magnets 19 which are arranged on the rotor disc 18 and located on one side of the stator assembly in a circumferential array mode, the other side of the rotor disc 18 is fixedly connected with a sun gear ring 7, and the sun gear ring 7 is a power output end of the axial magnetic field motor with the stator core.

The stator assembly comprises a plurality of stator cores 9, a plurality of coils 20, a stator yoke disc 21 and a stator tray 22, wherein the stator cores 9 are formed by laminating a plurality of silicon steel material sheets with different widths along the radial direction, at least one first tongue-and-groove 23 is arranged on a radial laminating surface, far away from one end of the rotor assembly, of the stator cores 9 and perpendicular to the rotating direction of the rotor assembly, a pole shoe 24 is arranged at one end close to the rotor assembly, the first tongue-and-groove 23 is a radial groove, the stator cores 9 connect the plurality of silicon steel material sheets into a whole through welding, and the welding surface at least comprises an end surface at one end of the first tongue-and-groove 23; stator yoke dish 21 forms for the disc thin slice of a plurality of silicon steel materials coincide along axial direction, perhaps stator yoke dish 21 forms for the disc thin slice of a plurality of silicon steel materials and the reinforcement disc piece 25 of non-silicon steel material coincide along axial direction, and reinforcement disc piece 25 is used for reinforcing stator yoke dish 21 to overcome the tensile ability of axial magnetism, and reinforcement ring piece 25 is stacked and is kept away from at stator yoke dish 21 one side of rotor subassembly, and stator yoke dish 21 cover is established on stator tray 22, and stator tray 22 and main shaft 1 fixed connection, stator core 9 and stator yoke dish 21 or with stator yoke dish 21 and stator tray 22 with the connection of mortise and tenon joint structure, the solid part of stator core 9's first tongue-and-groove 23 interval, for the tenon shoulder of mortise structure, the groove flank of first tongue-and-groove 23 is stator core 9's axial positioning.

The plurality of stator cores 9 are arranged coaxially and circumferentially to form a ring-shaped magnetic pole plane composed of a plurality of stator core magnetic poles, as shown in fig. 6, corresponding to the magnetic pole surfaces of the plurality of permanent magnets 18, and the permanent magnet flux of the motor passes through "N pole of the permanent magnet 18 to air gap 26 to stator core 9 to stator yoke disc 21 to adjacent stator core 9 to air gap 26 to S pole of adjacent permanent magnet 18" to form a closed magnetic circuit.

As shown in fig. 6, the coil 20 is in a concentrated winding form, and is sleeved between the pole shoe 24 of the stator core 9 and the first mortise 23, and the coil 20 and the stator core 9 are insulated and isolated by an insulated coil bobbin 27 or by coating an insulating material on the stator core 9.

The axial magnetic field motor with the single-stator and single-rotor structure has large unilateral magnetic pulling force, the magnetic pulling force is related to the magnetic energy product of the permanent magnet 19, the volume of the stator core 9, the size of magnetic flux generated by the coil 20 and the like, and therefore, the stability of the motor stator structure is ensured by adopting a proper structural form according to the size of the magnetic pulling force and the electromagnetic torque. The structural forms of the stator core 9, the stator yoke disc 21 and the stator tray 22 and the connection manner among the three can be specifically applied by those skilled in the art according to the following four examples of the present embodiment based on the stator core 9 having two first mortises 23, but not limited to the four examples.