CN218587022U

CN218587022U - Middle-mounted motor and electric bicycle

Info

Publication number: CN218587022U
Application number: CN202222689704.7U
Authority: CN
Inventors: 徐鹏飞; 王磊; 徐康宁
Original assignee: Dipson Digital Power System Suzhou Co ltd
Current assignee: Kingclean Electric Co Ltd; Lexy Electric Green Energy Technology Suzhou Co Ltd; Suzhou Kingclean Precision Machinery Co Ltd; Jiangsu Kingclean Intelligent Appliance Co Ltd
Priority date: 2022-10-12
Filing date: 2022-10-12
Publication date: 2023-03-07
Anticipated expiration: 2032-10-12

Abstract

The utility model discloses an in put motor and electric bicycle, including pivot and rotor core, the pivot is installed in rotor core's shaft hole, the pivot includes axle shape portion and profile of tooth portion, the surface machining of profile of tooth portion extends to the flank of tooth of tip, profile of tooth portion includes meshing district and non-meshing district, the meshing district with axle shape portion connects, the non-meshing position in the free end of pivot the non-meshing district the flank of tooth is equipped with the wall groove that the ring is cut, perhaps is in the meshing district with the juncture in non-meshing district the flank of tooth is equipped with the wall grooving that the ring is cut. The utility model provides an in put motor through the design that separates the rupture groove, when the profile of tooth portion that can make the pivot is impressed in rotor core's pivot mounting hole, the non-meshing district bears the impact force and the deformation that makes the flank of tooth produce can not conduct to the meshing district to guarantee that the profile of tooth in meshing district is unchangeable.

Description

In put motor and electric bicycle

Technical Field

The utility model relates to a motor art field especially relates to an in put motor and electric bicycle.

Background

In the existing middle-mounted motor, in order to simplify a transmission system, the tooth surface of the output end of a rotor tooth shaft is directly processed to be used as a primary transmission shaft. When the rotor shaft is fitted in the shaft hole of the rotor core, it is generally necessary to apply a press-fitting force to one end of the machined tooth surface so that the rotor shaft can be connected to the rotor core by interference fit. However, in the process of applying the pressing-in force, the pressing-in force is easy to cause the deformation of the tooth surface due to the transmission effect of the pressing-in force along the tooth surface, when the rotor rotates to drive the tooth shaft to be meshed with the transmission gear, the tooth shaft is abraded due to the deformation of the tooth surface, and the deformed tooth shaft of the rotor is uneven in stress, so that the service life of the centrally-mounted motor is influenced.

SUMMERY OF THE UTILITY MODEL

The embodiment of the utility model provides a technical problem who solves provides an in put motor and electric bicycle to lead to the problem of flank of tooth deformation when solving the pivot and impressing rotor core.

In order to solve the technical problem, the utility model provides an in put motor, including pivot and rotor core, the pivot is installed in rotor core's shaft hole, the pivot includes axle shape portion and profile of tooth portion, the surface machining of profile of tooth portion extends to the flank of tooth of tip, profile of tooth portion includes meshing district and non-meshing district, meshing district with axle shape portion connects, non-meshing district is located the free end of pivot the non-meshing district the flank of tooth is equipped with the wall groove of circular cutting, perhaps meshing district with the juncture in non-meshing district the flank of tooth is equipped with the wall groove of circular cutting.

Optionally, the depth of the breaking groove does not exceed the height of the tooth surface; and/or the length between the partition groove and the end of the tooth-shaped part is not more than one third of the length of the tooth surface.

Optionally, a groove is formed in the end face of the rotating shaft at one end of the shaft-shaped portion, and induction magnetic steel is installed in the groove.

Optionally, the groove is circular and has an inner conical surface at the center of the groove.

Optionally, the diameter of the groove is smaller than the diameter of the root circle.

Optionally, the induction magnetic steel is also circular, and the diameter of the induction magnetic steel is slightly larger than that of the groove, so that the induction magnetic steel is installed in the groove in an interference fit manner;

or the induction magnetic steel is connected in the groove through colloid.

Optionally, the tooth surface is a helical tooth or a straight tooth.

Optionally, the magnetic induction device further comprises a circuit board, an induction element and the rotating shaft, wherein the position of the induction element corresponds to the position of the induction magnetic steel, and the induction element is connected with the circuit board and sends an induction signal to the circuit board.

Optionally, the center of the induction element and the induction magnetic steel are located on the same axis.

Optionally, the inductive element is a magnetic chip.

Optionally, the transmission device further comprises a primary transmission wheel set and the rotating shaft, wherein the primary transmission wheel set comprises a primary transmission gear, and the primary transmission gear is meshed with the meshing area of the rotating shaft.

Optionally, the primary transmission gear comprises a central insert and an outer ring tooth part, the center of the central insert is provided with a shaft hole, the outer ring tooth part is connected to the outer circumference of the central insert and is coaxially arranged, the width of the outer ring tooth part in the axial direction is larger than that of the central insert, and both ends of the outer ring tooth part in the axial direction exceed the central insert; the central insert is made of a metal material, and the outer ring tooth part is made of a non-metal material.

Optionally, the outer circumferential surface of the central insert is provided with a reinforcing structure; the reinforcing structure is protruded or recessed from the surface of the outer circumference.

Optionally, the reinforcing structure is reinforcing teeth, knurls or splines arranged around the outer circumference of the central insert.

Optionally, the reinforcement tooth is split into at least three segments in the axial direction.

Optionally, the tooth crest of the reinforcing tooth is an arc surface or a surface with an obtuse included angle.

Optionally, the number of the splines is not less than 4, and the spline modulus is not less than 0.25.

Optionally, the outer ring teeth are injection molded on the outer circumference of the central insert.

Optionally, the primary transmission wheel set further comprises a primary transmission gear shaft, and the primary transmission gear shaft is coaxially connected with the primary transmission gear.

Optionally, the primary transmission gear shaft includes an input end, an output gear portion, and a support shaft, wherein the input end is connected to the central insert, the output gear portion is located between the input end and the support shaft, the support shaft has a diameter smaller than the output gear portion and the input end, the support shaft is connected to a needle bearing, and an outer diameter of the needle bearing is smaller than a tip circle diameter of the output gear portion.

Optionally, the input end and the central insert are connected by a spline or a keyway arranged on the surface of the input end.

Optionally, bearings are respectively arranged on the input ends on both sides of the central insert, and the bearings are at least partially located inside the outer ring tooth portion.

Optionally, the device further comprises a secondary transmission wheel set and a middle shaft transmission mechanism, wherein the secondary transmission wheel set comprises a secondary transmission gearwheel and a secondary transmission pinion which are coaxially connected, the secondary transmission gearwheel is meshed with the primary transmission gear shaft, and the secondary transmission pinion is meshed with the middle shaft transmission mechanism.

Optionally, the bottom bracket drive mechanism comprises:

a middle shaft;

the torque sensor is fixedly arranged on the middle shaft;

one end of the chain wheel positioning sleeve is connected with the torque sensor through a first isolator, and the other end of the chain wheel positioning sleeve is fixedly connected with the chain wheel;

the middle shaft gear is connected to the chain wheel positioning sleeve through a second isolator; and the bottom bracket gear meshes with the secondary drive pinion.

Optionally, the bottom bracket gear comprises:

a gear portion;

a support portion located at an inner side of the gear portion in a radial direction, for being connected with the chain wheel positioning sleeve through a ball bearing;

and the transmission part is positioned on one side of the supporting part in the axial direction and is used for being connected with the chain wheel positioning sleeve through the second one-way clutch.

Alternatively, the gear portion, the support portion, and the transmission portion form an L-shaped layout, and the transmission portion is located outside the support portion in the axial direction.

Optionally, the chain wheel positioning sleeve is provided with an annular step structure, wherein the first one-way device is arranged in the annular step structure, the second one-way device is close to the annular step structure, and the outer diameter of the transmission part does not exceed the outer diameter of the annular step structure.

Optionally, the chain wheel positioning sleeve is connected with the middle shaft through two needle bearings, and the two needle bearings are correspondingly located on two sides of the supporting portion.

Optionally, the two needle bearings are a second needle bearing and a third needle bearing, respectively, wherein the second needle bearing is located outside the third needle bearing, and the third needle bearing is connected to the torque sensor.

Optionally, the third needle bearing has an inner diameter greater than an inner diameter of the second needle bearing.

Optionally, the torque sensor is fixedly connected with the middle shaft through a spline; the middle shaft is a hollow tubular shaft, and two ends of the middle shaft are respectively connected with a crank.

Optionally, the rotor core includes multiple groups of iron core stamped sheets, each group of iron core stamped sheets includes at least one iron core stamped sheet, the number of poles of the iron core of each iron core stamped sheet is N, M notches are arranged in the shaft hole of each iron core stamped sheet, M is not an integral multiple of N, after the multiple groups of iron core stamped sheets are laminated to form the rotor core, at least one group of iron core stamped sheet notches and other groups of iron core stamped sheet notches are at least partially staggered in projection on the plane where any iron core stamped sheet is located.

Optionally, the difference between the rotation angles of two adjacent sets of iron core laminations is K, where K =360 × N/N, and N is a natural number less than N; the rotation angle difference K is not equal to 360 x M/M, and M is a natural number smaller than M, so that the gaps of the multiple groups of iron core punching sheets are spirally arranged on the rotating shaft mounting hole of the rotor iron core.

Optionally, M is larger than or equal to 2, and M notches are uniformly distributed on the edge of the shaft hole.

Optionally, the travel of the helical shape in the circumferential direction comprises at least 1 circumference.

Optionally, the helical shape is an integer number of circles.

Optionally, the notch is triangular, arc-shaped, semicircular, rectangular or trapezoidal.

Optionally, the iron core stamped sheet comprises an iron core yoke portion and iron core tooth portions arranged in an array manner around the circumference of the iron core yoke portion, two ends of the outer edge of each iron core tooth portion are respectively provided with pole shoes extending towards two sides, and a magnetic steel installation groove is formed between every two adjacent iron core tooth portions; the iron core tooth part is of a fan-shaped structure, and the radius of the fan-shaped structure is smaller than that of the iron core stamped steel. Optionally, the circle centers of all the iron core tooth portions (the circle centers of the fan-shaped structures are on the same circle with the axis of the rotor iron core as the circle center, the arrangement direction of each fan-shaped structure points to the outer side along the connecting line direction of the circle center of the iron core stamped steel and the circle center of the iron core tooth portion, and the middle points of the arc lines of the fan-shaped structures are located on the outer circle of the iron core stamped steel at the same time.

Optionally, the core tooth portion is connected to the core yoke portion through a magnetic isolation strip, and a width of the magnetic isolation strip is smaller than a minimum width of the core tooth portion.

Optionally, a circular hole is formed in a sector of the core tooth part, and the distance between the circular hole and three sides of the sector is equal.

Optionally, the iron core stamped sheets include an open-structure iron core stamped sheet and a closed-structure iron core stamped sheet, wherein the open-structure iron core stamped sheet is arranged between the closed-structure iron core stamped sheets; and pole shoes of two adjacent iron core tooth parts of the closed-structure iron core stamped sheet are connected to form a closed structure.

Optionally, the iron core punching sheet with the closed structure is further provided with a supporting block at the iron core yoke part between two adjacent magnetic separation strips so as to position the short edge of the magnetic steel.

The utility model also provides an electric bicycle, including above pivot, or above detecting system, or above drive system, or in put the motor.

Implement the utility model discloses, following beneficial effect has:

the utility model provides an in put motor through the design that cuts off the groove in the pivot, when the profile of tooth portion that can make the pivot is impressed in rotor core's pivot mounting hole, the non-meshing district bears the impact force and the deformation that makes the flank of tooth produce can not conduct to the meshing district to guarantee that the profile of tooth in meshing district is unchangeable. And simultaneously, the utility model provides an in put the motor and also overcome the recess and lead to the lifting surface area of pivot terminal surface reduce and use the induction magnet steel that clearance fit connects to lead to the problem of flank of tooth deformation.

The utility model provides an in put motor can overcome installation response magnet steel and lead to the pivot and the flank of tooth deformation that lead to in the impressing force concentration of pivot terminal surface to just also make the position between response magnet steel and the sensing element correspond more accurately, thereby make detecting system's detection effect better.

The utility model provides an in put motor, owing to be provided with in the pivot and separate the groove to after making the pivot impress rotor core, the flank of tooth in meshing district can not produce because of the power of impressing and warp or reduce the deformation amplitude by a wide margin in the pivot, thereby makes the meshing district and the one-level drive gear meshing driven in-process of transmission shaft, and transmission effect between the two is better, can not produce interlock damage each other because the flank of tooth warp, guarantees transmission effect and pivot, one-level drive gear's life.

The utility model provides a centrally-mounted motor, because of used breach dislocation arrangement's rotor core to reduce or eliminate because of the unanimous beating problem that leads to the pivot after the rotor core of impressing of breach position, make motor and central motor rotate more steadily, and because the design at a distance from the break groove reduces substantially or even has eliminated the power of impressing completely, overcome the atress area that the recess leads to the pivot terminal surface simultaneously and reduced and use the response magnet steel that interference fit connects to lead to the problem that the flank of tooth warp.

It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the application.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the application and are not to be construed as limiting the application.

Fig. 1 is a schematic structural diagram of a rotor core according to an embodiment of the present invention;

FIG. 2 is an enlarged partial schematic view at A of FIG. 1;

fig. 3 is a schematic structural diagram of an open-structure core sheet according to an embodiment of the present invention;

fig. 4 is a schematic perspective view of an open-structured iron core sheet according to an embodiment of the present invention;

fig. 5 is a schematic structural diagram of a closed-structure core sheet in an embodiment of the present invention;

fig. 6 is a schematic perspective view of a closed-structure core sheet in an embodiment of the present invention;

fig. 7 is a schematic structural diagram of an open-structure core stamped sheet in an embodiment of the present invention;

fig. 8 is a schematic structural view of a rotor in an embodiment of the present invention;

fig. 9 is a schematic cross-sectional view of a rotor in an embodiment of the invention;

fig. 10 is an assembly schematic view of a rotor in an embodiment of the invention;

fig. 11 is an assembly diagram of a rotor according to an embodiment of the present invention;

fig. 12 is a schematic structural view of the rotating shaft in the embodiment of the present invention;

fig. 13 is a schematic structural view of a primary transmission wheel set in an embodiment of the present invention;

fig. 14 is a schematic sectional view of a primary transmission wheel set according to an embodiment of the present invention;

FIG. 15 is a schematic structural view of a primary transmission gear according to an embodiment of the present invention;

FIG. 16 is a schematic sectional view of a primary transmission gear according to an embodiment of the present invention;

fig. 17 is a schematic structural view of a center insert in an embodiment of the present invention;

fig. 18 is a schematic structural view of a primary transmission gear shaft in an embodiment of the present invention;

fig. 19 is a schematic view of an assembly structure of a secondary transmission wheel set according to an embodiment of the present invention;

fig. 20 is a schematic structural view of the middle shaft transmission mechanism in the embodiment of the present invention;

fig. 21 is a schematic sectional view of the middle shaft transmission mechanism in the embodiment of the present invention;

fig. 22 is a schematic structural view of the middle shaft gear in the embodiment of the present invention;

fig. 23 is a schematic sectional view of the middle shaft gear in the embodiment of the present invention;

FIG. 24 is a schematic view of a portion of a drive train according to an embodiment of the present invention;

FIG. 25 is a schematic diagram of a portion of a drive train according to an embodiment of the present invention;

FIG. 26 is a schematic diagram of a portion of a drive train in an embodiment of the present invention;

fig. 27 is a schematic structural view of a middle motor according to an embodiment of the present invention;

fig. 28 isbase:Sub>A sectional view taken along the linebase:Sub>A-base:Sub>A in fig. 27 according to an embodiment of the present invention;

fig. 29 is a schematic sectional structure view of a mid-motor according to an embodiment of the present invention;

fig. 30 is a schematic structural view of a rotating shaft (2300A) in the embodiment of the present invention;

fig. 31 is a schematic cross-sectional structure diagram of a mid-motor in an embodiment of the present invention;

fig. 32 is a schematic view of an assembly structure of a mid-motor according to an embodiment of the present invention;

fig. 33 is a schematic structural view of a rotating shaft (2300B) in the embodiment of the present invention;

fig. 34 is a schematic cross-sectional structure diagram of a middle motor in an embodiment of the present invention;

fig. 35 is a schematic perspective view of an embodiment of the present invention;

fig. 36 is a schematic view of the mounting structure of the main body cover and the rotary transformer according to the embodiment of the present invention.

Reference numbers in the figures:

1000-main chassis; 1001-motor installation cavity; 1002-rotating and changing the installation cavity; 1003-transmission cavity;

1010-a stator mounting section; 1011-annular groove;

1020-a separator; 1022 — a second bearing installation chamber; 1023-a second ball bearing;

1030-radiating ribs;

1100-motor cover; 1110-a first bearing installation chamber; 1111-a first ball bearing;

1200-a transition casing;

1210-shaft hole;

1220-annular bead; 1230-fixed block; 1240-a bearing installation chamber;

1300-main machine cover;

2000-motor assembly;

2100-a stator;

2200-a rotor core;

2210-iron core punching; 2211-notch; 2212-shaft hole; 2213-core yoke; 2214-core teeth;

2215-magnetic steel mounting groove; 2216-pole piece; 2217-magnetic isolation strip; 2218-round hole; 2219-support block;

2220-mounting hole for rotary shaft;

2210A-open structure iron core punching sheet; 2210B-closed structure iron core punching sheet;

2300-a rotation axis; 2300A-a shaft; 2300B-a shaft;

2310-axial portion;

2320-tooth profile; 2321-engaging zone; 2322-non-engagement zone; 2323-separating groove; 2324-grooves; 2345-induction of magnetic steel; 2346-inner conical surface;

2340 — rotor connection;

2350-power output;

2360-rotating mounting end; 2361-a third fixation structure;

2370-rotor connection end;

2380-power take off;

3000-rotary transformer;

3100-a rotating stator; 3120-annular groove;

3200-a rotating variable rotor;

4000-one stage of transmission wheel set;

4100-primary transmission gear;

4110-outer ring teeth;

4120-central insert; 4121-reinforcement teeth;

4200-a primary drive gear shaft;

4210-input terminal;

4220-output toothing;

4230-supporting shaft;

4240-a first needle bearing;

5000-a secondary transmission wheel set;

5100-secondary driving big gear;

5200-secondary drive pinion;

6000-middle shaft transmission mechanism;

6001-second needle bearing; 6002-third needle bearing; 6003-third ball bearing;

6100-middle axis;

6200-a crankset locating sleeve; 6210-a ring step structure;

6300-torque sensor;

6400-middle shaft gear; 6410-a gear part; 6420-a support portion; 6430-a transmission;

6500-first isolator;

6600-second isolator;

6700-dental plate connection structure;

7100-circuit board; 7110-sensing element;

7200-bearing support.

Detailed Description

In order to make the above objects, features and advantages of the present invention more comprehensible, embodiments of the present invention are described in detail below with reference to the accompanying drawings. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention. The present invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein, as those skilled in the art will be able to make similar modifications without departing from the spirit and scope of the present invention.

It will be understood that when an element is referred to as being "secured to" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. The terms "vertical," "horizontal," "left," "right," and the like are used herein for purposes of illustration only.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used in the description of the invention herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.

In the scheme adopted in the prior art, notches of all iron core stamped sheets 2210 are overlapped, and through grooves which are axially arranged and run through two ends of a rotor iron core are formed in a rotating shaft mounting hole 2220 formed by laminating. Because iron core punching 2210 is by same mould stamping forming, just so make the mould punching process in, if the stamping deformation of a certain breach and other breachs is different among them, after a plurality of iron core punching are folded, the logical groove of being formed by the breach in same position will be different with the holding power of other logical grooves to the countershaft to just make whole rotor core produce easily and beat.

As shown in fig. 1 to 7, this embodiment provides a rotor core, which includes multiple sets of iron core laminations, each set of iron core laminations includes at least one iron core lamination 2210, the number of iron core poles of the iron core lamination 2210 is N (N is an even number greater than 2), M notches 2211 are disposed in a shaft hole 2212 of the iron core lamination 2210, M is not an integer multiple of N, after the multiple sets of iron core laminations 2210 are laminated to form the rotor core, projections of the notches 2211 of at least one set of iron core laminations and the notches 2211 of other sets of iron core laminations on a plane where any one of the iron core laminations 2210 is located do not overlap (or are at least partially staggered). In this embodiment, the notches 2211 are formed in the axial hole 2212 of the iron core stamped piece 2210, so that the notches 2211 are arranged in a staggered manner in the axial direction of the rotating shaft and are connected with the rotating shaft in an interference fit manner after being laminated, and the notch defects caused by process reasons can be uniformly distributed in the circumferential direction of the rotating shaft, thereby avoiding the concentration of the notches of the defects.

The utility model provides a rotor core is through setting up the breach on the shaft hole to make breach dislocation arrangement when overlying the shaping, thereby make rotor core shaping back, reduce or eliminate because of the breach leads to the pivot to impress the problem of beating behind the rotor core.

The angle difference between two adjacent sets of iron core laminations 2210 is K (namely, the adjacent sets of iron core laminations are stacked again after rotating by the angle K), wherein K =360 × N/N, and N is a natural number smaller than N; the angle difference K is not equal to 360 × M/M (to avoid overlapping different gaps after the rotor core rotates through the angle K), and M is a natural number smaller than M, so that the gaps 2211 of the multiple sets of iron core laminations are arranged in a spiral shape on the rotating shaft mounting hole 2220 of the rotor core.

Generally, the number of the notches M should be much smaller than the number N of the iron core poles, so as to reduce the number of the openings of the notches and make the iron core lamination have a sufficiently large contact area with the rotating shaft.

Further, when adopting the utility model discloses the mode of gyration is folded towards the iron core and is pressed, can overcome the iron core towards the too big defect of unilateral dynamic balance volume of iron core towards the unilateral skew of piece in the stamping process, towards the iron core of piece evenly distributed on the circumference to make the dynamic balance volume of iron core circumferencial direction keep unanimous, thereby sparingly produce line dynamic balance's debug time.

Especially when the iron core punching sheet punching press leads to one side size to be bigger or smaller, if direct pressure of folding can cause whole rotor core unilateral skew, unilateral dynamic balance volume is too big to lead to dynamic balance volume grow. The utility model discloses a gyration mode is folded and is pressed and to be guaranteed that each iron core is towards piece and all forms certain contained angle with last piece, and the bad part of size also can squint, and rotatory round or many circles back can be to the not good part of size evenly distributed on the circumference, and each department's equilibrium volume of iron core circumferencial direction is unanimous basically can be guaranteed to this kind of mode, and whole dynamic balance volume can diminish.

Optionally, M may be multiple, and M notches are uniformly distributed at the edge of the shaft hole 2212, so that when the iron core sheet is in interference fit with the rotating shaft, the contact area between each position of the shaft hole of the iron core sheet and the rotating shaft is equal, and the stress in each direction is also equal.

The helical shape includes at least 1 circumference, thereby enabling the gap 2211 to be evenly distributed over the circumference of the shaft, resulting in uniform stress on the gap 2211 in all directions;

the helical shape is an integer number of circles, i.e., may be 1, 2 or more circles, thereby enabling the notches 2211 to be evenly distributed throughout the circumference of the shaft, and enabling the notches 2211 to be evenly stressed in all directions.

The notch 2211 is triangular, arc-shaped, semicircular, rectangular or trapezoidal, and the notch 2211 may be any combination of the above shapes, or the notch 2211 may be other non-illustrated irregular shapes. In order to reduce the stress concentration caused by the gap 2211, the gap may be designed to have a circular arc transition structure.

As shown in fig. 7, the core plate 2210 includes a core yoke portion 2213 and core tooth portions 2214 arranged in an array around the circumference of the core yoke portion 2213, two ends of the outer edge of each core tooth portion 2214 are respectively provided with pole shoes 2216 extending to two sides, and a magnetic steel mounting groove 2215 is formed between two adjacent core tooth portions 2214; the core tooth 2214 is a sector structure with a radius R1 smaller than the radius R of the core sheet. The centers of the circle of the fan-shaped structures of all the core tooth portions 2214 are on the same circle with the axis of the rotor core as the center, the radius thereof is R2, and R = R1+ R2 is satisfied. Specifically, the arrangement direction of each sector structure points outward along the connection line of the center of the core piece 2210 and the center of the core tooth portion 2214; and the midpoint of the arc of the fan-shaped structure is located on the outer circle of the core plate 2210 simultaneously. The iron core tooth 2214 of the iron core punching sheet is designed to be an eccentric circle structure relative to the center of the whole iron core punching sheet, so that the waveform can be ensured to be closer to a sine wave, and harmonic waves are reduced.

The core tooth 2214 is connected to the core yoke 2213 through a flux barrier 2217, and the width of the flux barrier 2217 is smaller than the minimum width of the core tooth 2214, so that the flux leakage of the flux barrier can be effectively reduced.

Be equipped with round hole 2218 on the sector of iron core tooth portion 2214, round hole 2218 equals with the trilateral distance of sector, through round hole 2218 structural design, can guarantee that magnetic density is even.

The iron core stamped sheet 2210 comprises an open structure iron core stamped sheet 2210A and a closed structure iron core stamped sheet 2210B, wherein the open structure iron core stamped sheet 2210A is arranged between the closed structure iron core stamped sheets 2210B; in the closed-end structure iron core stamped steel 2210B, pole shoes 2216 of two adjacent iron core tooth portions 2214 are connected to form a closed-end structure. Through the interval structure design of closed structure iron core stamped steel 2210B and open structure iron core stamped steel 2210A, thereby the structural strength of the whole rotor core can be increased. As shown in fig. 1-2, a closed-structure core stamped piece 2210B is arranged at two ends and in the middle of the whole rotor core in a 2-piece combination manner; the open-structured core stampings 2210A are arranged between the closed-structured core stampings 2210B in a 14-piece combination manner. In a specific implementation process, the usage ratio of the open-structure core stamped sheet 2210A to the closed-structure core stamped sheet 2210B is not limited thereto, and those skilled in the art may increase or decrease the usage ratio according to implementation requirements.

The core piece 2210B with a closed structure is further provided with a support block 2219 at the core yoke portion 2213 between two adjacent magnetic separation bars 2217, so as to position the short side of the magnetic steel and reduce magnetic leakage. The supporting block 2219 can play a role in positioning and fixing the magnetic steel. Specifically, the magnet steel is impressed magnet steel mounting groove 2215 back, thereby supporting shoe 2219 produces the deformation of certain degree and pushes up on the side of magnet steel, makes magnet steel and magnet steel mounting groove 2215 radially form interference fit, and the magnet steel supports tightly on protruding edge or limit structure in the magnet steel mounting groove 2215 outside, has effectively reduced the unbalance amount change that the magnet steel displacement caused and the vibration noise who consequently produces.

Due to the design of the interval structure between the closed-structure core stamped piece 2210B and the open-structure core stamped piece 2210A, the supporting blocks 2219 are periodically arranged on the radial inner side surface of the magnetic steel mounting groove 2215 of the rotor core formed after the closed-structure core stamped piece 2210B and the open-structure core stamped piece 2210A are alternately laminated. That is, in any core piece 2210, the supporting blocks 2219 are periodically distributed with respect to the center of the core piece 2210. After a plurality of iron core stamped sheets 2210 are stacked to form a rotor iron core, the supporting blocks 2219 are distributed in the axial direction of the whole rotor iron core at intervals, and in any magnetic steel mounting groove 2215, the intervals of the supporting blocks 2219 are random.

As shown in fig. 8 to 12, this embodiment further provides a rotor, which includes a rotating shaft 2300 and the rotor core 2200 provided in the above embodiments, wherein the rotating shaft 2300 is connected in the rotating shaft mounting hole 2220 of the rotor core 2200 by interference fit. The rotating shaft 2300 in this embodiment may be a conventional rotor output shaft (i.e., the output end of the rotating shaft is also in a shaft shape), or may be a rotor pinion (i.e., a tooth surface is machined at the output end of the rotating shaft to engage with a gear).

The utility model provides a rotor, pivot 2300 are connected with rotor core 2200 through interference fit's mode, through the iron core on rotor core 2200 towards the breach arrangement of piece 2210, with reduce or eliminate because of the unanimous beating problem that leads to the pivot after impressing rotor core in breach position.

Alternatively, in this embodiment, when the rotating shaft 2300 is a rotor toothed shaft, the rotating shaft 2300 includes a shaft-shaped portion 2310 and a toothed portion 2320, and the shaft-shaped portion 2310 is connected to the rotor core 2200 by interference fit; the tooth-shaped part 2320 is provided with a tooth surface extending to the end part by surface machining, the tooth-shaped part 2320 comprises a meshing area 2321 and a non-meshing area 2322, the meshing area 2321 is connected with the shaft-shaped part 2310, the meshing area 2321 is used for meshing with a transmission gear so as to output the power of a rotor, the non-meshing area 2322 is arranged at the free end of the rotating shaft 2300, and the tooth surface at the junction of the meshing area 2321 and the non-meshing area 2322 is provided with a circular cutting partition groove 2323, and the tooth surface can be helical teeth or straight teeth. By the design of the partition slot 2323, when the tooth-shaped portion 2310 of the rotating shaft 2300 is pressed into the rotating shaft mounting hole 2220 of the rotor core 2200, the non-meshing region 2322 bears impact force, so that deformation generated by the tooth surface is not transmitted to the meshing region 2321, and the tooth shape of the meshing region 2321 is ensured to be unchanged. The blocking slot 2323 may also be provided at the non-engagement region 2322 so that a portion of the non-engagement region is left outside the engagement region 2321 to be better engaged with the driving gear.

When the rotating shaft 2300 is pressed into the rotating shaft mounting hole 2220 of the rotor core 2200 provided in the above embodiment, due to the staggered arrangement of the notches 2211 of the core sheets 2210 of the rotor core 2200, the pressing force of the rotating shaft 2300 and the rotating shaft mounting hole 2220 is larger, so that the design of the partition groove 2323 is adopted for the rotating shaft 2300, and the tooth shape of the meshing area 2321 can be better ensured to be unchanged. Due to the fact that the scheme that the rotor core is staggered with the notches in the embodiment is used, the pressing-in area is larger (when the traditional rotor core is pressed in, the notches are not in contact with the rotating shaft), the pressing-in force of the rotating shaft 2300 is larger when the rotating shaft is pressed in, and when the pressing-in force is applied to the end of the rotating shaft 2300, the change of the tooth profile of the end of the rotating shaft 2300 is larger; by adopting the structural design of the partition groove 2323 in the embodiment, the press-in force borne by the tooth surface on the inner side of the partition groove 2323 is smaller or the transmission of the press-in force on the tooth surface can be completely blocked, so that the tooth surface is deformed less or not deformed in the process of pressing the rotating shaft 2300 into the rotor core.

It can be known by those skilled in the art that when the structure of the rotor core 2200 and the structure of the partition groove 2323 provided in the above embodiments are used together, the partition groove 2323 can greatly reduce the influence of the deformation of the tooth surface when the rotating shaft 2300 is pressed into the structure of the rotor core 2200, so that the effect of the pressing force caused by the rotor core 2200 with the staggered notches is better; however, when the rotor core 2200 is designed in a conventional structure (the notches are arranged linearly in the axial direction), the influence of the pressing force on the deformation of the tooth surface can be effectively reduced.

The depth of the isolating groove 2323 does not exceed the height of the tooth surface so as to ensure that the rotating shaft 2300 has good mechanical strength at the tooth-shaped portion 2320, and if the depth of the isolating groove 2323 exceeds the height of the tooth surface, the depth of the isolating groove 2323 is far into the root circle, so that the strength of the isolating groove is insufficient when the rotating shaft 2300 is pressed into the rotor. Therefore, the bottom surface of the partition groove 2323 should be higher than the circumference of the root circle, and preferably, the depth of the partition groove may be less than half of the tooth surface height, which is optimal around the reference circle, so as to ensure that the pressing force on the rotating shaft 2300 can be better transmitted to the shaft-shaped portion 2310, the influence of the tooth deformation of the non-meshing region on the meshing region can be completely avoided by cutting to the tooth root, and the strength of the whole rotating shaft in pressing the rotor is not good according to the technical data of intersection, but the present application considers the comprehensive consideration of the tooth deformation and the force that the shaft can bear, that is, the tooth tip is the most easily deformed when the rotating shaft is pressed by the size of the shaft, and the tooth tip deformation caused in the transmission process can be minimized.

The length from the separating groove 2323 to the end of the rotating shaft 2300 is not more than one third of the length of the tooth surface, so that the structural layout design of the rotating shaft 2300 can be optimized.

Alternatively, as shown in fig. 11, a groove 2324 is provided on an end face of the rotating shaft 2300 at one end of the shaft-shaped portion 2310, an induction magnetic steel 2345 is installed in the groove 2324, and the induction magnetic steel 2345 is disposed in the groove 2324, so that the structure of the rotating shaft 2300 can be utilized more reasonably, on one hand, the pressing-in force of the rotating shaft 2300 can be better transmitted to the shaft-shaped portion 2310, on the other hand, the deformation of the tooth surface caused during the transmission process can be minimized, and on the other hand, the induction magnetic steel 2345 can be fixed.

When the end surface of the rotating shaft 2300 is provided with the groove 2324, the stressed area of the end surface of the rotating shaft 2300 is greatly reduced, so that the impact force is more greatly influenced on the deformation of the tooth surface when acting on the end surface of the rotating shaft 2300, and the conventional tooth surface is continuous, so that the tooth surface of the meshing part is also deformed due to the continuous transmission of the tooth surface deformation, and the meshing abrasion of the whole rotating shaft in the meshing process with the transmission gear is increased; again, the design of the partition 2323 may better address this issue.

Recess 2324 is circular, and is equipped with interior conical surface 2346 in the center of recess 2324, and correspondingly, induction magnetic steel 2345 is also circular, and induction magnetic steel 2345 and the shape adaptation of recess 2324 to make induction magnetic steel 2345 can pack into recess 2324. At this moment, the degree of depth of recess 2324 should be more than or equal to induction magnet steel 2345's height to make induction magnet steel 2345 after packing into in recess 2324, induction magnet steel 2345 can be embedded inside recess 2324, avoids induction magnet steel 2345 to expose, thereby plays the guard action to induction magnet steel 2345.

The diameter of recess 2324 is less than the diameter of the root circle of flank of tooth to avoid recess 2324 too big and lead to the inside area of transmission push-in force of root circle undersize, and can guarantee to respond to magnetic steel 2345's guard action after magnetic steel 2345 packs into.

The induction magnetic steel 2345 is also circular, and the diameter of the induction magnetic steel 2345 is slightly larger than that of the groove 2324, so that the induction magnetic steel 2345 is installed in the groove 2324 in an interference fit manner; alternatively, one skilled in the art can alternatively couple induction magnetic steel 2345 into recess 2324 through glue.

When the induction magnetic steel 2345 is connected in the groove 2324 in an interference fit manner, the tooth surface around the groove is necessarily deformed; therefore, the utility model discloses wall groove 2323 design among the technical scheme, the problem of solution flank of tooth deformation transmission to meshing area 2321 that can be perfect to guarantee that meshing area 2321's profile of tooth is unchangeable, guarantee pivot 2300's life.

The present embodiment further provides a method for forming a rotor core, including:

providing iron core stamped sheets 2210 and grouping the iron core stamped sheets, wherein each group of iron core stamped sheets comprises at least one iron core stamped sheet 2210, and a notch 2211 is formed in the circumference of a shaft hole of at least one iron core stamped sheet 2210 in each group of iron core stamped sheets;

the iron core laminations 2210 are laminated to form a rotor iron core 2200, and a deflection angle of 360 × N/N is formed between the notches of two adjacent iron core laminations 2210, wherein N is a natural number smaller than N.

The utility model provides a rotor core forming method, fold the pressure equipment through the mode of gyration and form, make breach 2211 form the spiral on pivot mounting hole 2220 and arrange, breach 2211 evenly distributed on the circumference, thereby can overcome iron core towards piece 2210 stamping process because of the too big defect of unilateral dynamic balance volume of iron core towards the unilateral skew of piece results in, iron core towards piece 2210 evenly distributed of unilateral skew is on the circumference, thereby make the dynamic balance volume of iron core circumferencial direction keep unanimous, thereby sparingly produce dynamic balance's debugging time.

When the number M of the notches is multiple, the notches are uniformly distributed around the shaft hole of the iron core stamped steel, and the deflection angle 360 x N/N is not equal to 360 x M/M (M is a natural number less than M) at the moment, so that the notches form M spiral shapes in the rotating shaft mounting hole.

The present embodiment further provides a rotor, which includes a rotating shaft 2300 and a rotor core 2200 manufactured and molded by the molding method provided in the above embodiments, wherein the rotating shaft 2300 is connected in a manner of interference fit in a rotating shaft mounting hole 2220 of the rotor core 2200.

The utility model provides a rotor is through setting up breach 2211 on the shaft hole of iron core towards piece 2210 to make breach dislocation arrangement when the iron core is folded towards the piece and is pressed, thereby make rotor core shaping back, reduce or eliminate because of the breach leads to the pivot to impress the rotor beat problem behind rotor core 2200.

Further, when adopting the utility model discloses the mode of gyration is folded the iron core towards the piece and is pressed, can overcome the iron core towards the too big defect of unilateral dynamic balance volume that leads to because of the iron core towards the unilateral skew of piece in stamping process, with the iron core towards piece evenly distributed of unilateral skew on the circumference to the dynamic balance volume that makes iron core circumferencial direction keeps unanimous, thereby sparingly produces the debugging time of line dynamic balance.

The present embodiment also provides a motor, which includes the rotor core provided in the above embodiment or the rotor provided in the above embodiment.

The present embodiment also provides a center-mounted motor, which includes the rotor core provided in the above embodiment or the rotor provided in the above embodiment.

The utility model provides a motor and medium motor, because of used breach dislocation's rotor core 2200, thereby reduce or eliminate because of the unanimous beating problem that leads to the pivot after the rotor core of impressing of breach position, it is more steady to make motor and medium motor rotate, and because the design that cuts off groove 2323 reduces substantially or even eliminated the power of impressing completely, overcome recess 2324 simultaneously and lead to the lifting surface area of pivot terminal surface to reduce, and use induction magnet steel 2345 that interference fit connects to lead to the problem that the flank of tooth warp.

Combine fig. 25 to show, the embodiment of the utility model provides a detection system is still provided, including circuit board 7100, sensing element 7110 and the pivot 2300 that the embodiment provided above, the flank of tooth of pivot 2300 sets up and cuts off groove 2323, has recess 2324 on the terminal surface of pivot 2300 to set up response magnet steel 2345 in recess 2324, sensing element 7110's position is just corresponding with response magnet steel 2345's position, sensing element 7110 is connected with circuit board 7100, and sends inductive signal for circuit board 7100.

The detection system provided by the embodiment can overcome the deformation of the rotating shaft and the tooth surface caused by the concentrated pressing force of the end face of the rotating shaft 2300 due to the installation of the induction magnetic steel 2345, so that the position correspondence between the induction magnetic steel 2345 and the induction element 7110 is more accurate, and the detection effect of the detection system is better.

In this embodiment, the center of the sensing element 7110 and the sensing magnetic steel 2345 are located on the same axis, so that the sensing element 7110 has a better detection effect on the sensing magnetic steel 2345.

In this embodiment, the sensing element 7110 is a magnetic encoding chip. It will be appreciated by those skilled in the art that the inductive element 7110 may be implemented with other elements that function as a magnetic chip.

With reference to fig. 24 to 26, the present embodiment further provides an intermediate motor transmission system, which includes a first-stage transmission wheel set 4000 and the rotating shaft 2300 provided in the above embodiments, where the first-stage transmission wheel set 4000 includes a first-stage transmission gear 4100, and the first-stage transmission gear 4100 is engaged with the engagement area 2321 of the rotating shaft 2300. In the transmission system provided by this embodiment, since the partition groove 2323 is provided on the rotating shaft 2300, after the rotating shaft 2300 is pressed into the rotor core 2200, the tooth surface of the meshing zone 2321 on the rotating shaft 2300 does not deform or the deformation amplitude is greatly reduced due to the pressing force, so that in the process of meshing transmission between the meshing zone 2321 of the transmission shaft 2300 and the first-stage transmission gear 4100, the transmission effect between the two is better, mutual meshing damage due to the deformation of the tooth surface is avoided, and the transmission effect and the service life of the rotating shaft 2300 and the first-stage transmission gear 4100 are ensured.

With reference to fig. 13 to 17, the present embodiment provides a transmission system in which the primary transmission gear 4100 includes a central insert 4120 and an outer ring tooth portion 4110, the center of the central insert 4120 has a shaft hole, the outer ring tooth portion 4110 is connected to the outer circumference of the central insert 4120 and is coaxially arranged, the width of the outer ring tooth portion 4110 in the axial direction is larger than that of the central insert 4120, and both ends of the outer ring tooth portion 4110 in the axial direction exceed the central insert 4120; the central insert 4120 is made of a metallic material and the outer ring teeth 4110 is made of a non-metallic material. In the transmission system provided by the embodiment, the rotating shaft 2300 is adopted to directly drive the first-stage transmission gear 4100, so that the rotating speed of the rotating shaft 2300 is high, and the first-stage transmission gear 4100 made of an integral metal material has large moment of inertia, thereby causing energy loss; the primary transmission gear 4100 made of non-metallic materials has the problems of large contact surface stress and incapability of meeting the transmission requirement of support strength; therefore, the central insert 4120 made of a metal material and the outer ring tooth 4110 made of a non-metal material are adopted in the embodiment, and the width of the outer ring tooth 4110 is larger than that of the central insert 4120, so that on one hand, a larger contact area between the outer ring tooth 4110 and the rotating shaft 2300 is ensured, the contact stress to the outer ring tooth 4110 is reduced, on the other hand, the integral rotational inertia of the central insert 4120 and the outer ring tooth 4110 is lower, the energy loss in the transmission process is reduced, and on the other hand, the requirement for transmission torque can be met due to the fact that the size of the central insert 4120 made of the metal material is smaller.

Referring to fig. 17, the present embodiment provides a transmission system in which the outer circumferential surface of the center insert 4120 is provided with a reinforcing structure; the reinforcing structure is protruded or recessed on the surface of the outer circumference. The design of the reinforcing structure can effectively increase the connecting area between the central insert 4120 and the outer ring tooth portion 4110, so that the combination between the central insert 4120 and the replacement insert 4110 is more stable, and the overall shape can be kept unchanged in the transmission process; in particular, in the case where the width of the center insert 4120 is reduced, the problem of the reduction in the connection area can be compensated for by the reinforcing structure.

The present embodiment provides a transmission system wherein the reinforcement structure is reinforcement teeth 4121, knurls or splines arranged around the outer circumference of the central insert 4120.

The present embodiment provides a transmission system in which the reinforcing teeth 4121 are split into at least three segments in the axial direction. Such a design can enable the outer ring tooth portion 4110 to not only further increase the connection area with the central insert 4120, but also overcome the axial stress during the transmission process, and maintain the structural stability of the central insert 4120 and the outer ring tooth portion 4110 during the transmission process.

The tooth crest of the reinforcing teeth 4121 is an arc surface or a surface having an obtuse included angle. In the embodiment, the protruded top cannot be made into a sharp corner, the width of the top is not less than 0.2mm, stress concentration during injection molding is avoided, and the sharp corner end is broken when large torque is borne.

In the transmission system provided by the embodiment, when the splines are adopted between the central insert 4120 and the outer ring tooth portion 4110, the number of the splines is not less than 4, and the spline modulus is not less than 0.25.

In the transmission system provided by the embodiment, the outer ring tooth portions 4110 are injection molded on the outer circumference of the central insert 4120, so that the connection between the central insert 4120 and the outer ring tooth portions 4110 is tighter, and the transmission system is not easy to deform in the transmission process.

With reference to fig. 13 to 17, in the transmission system provided in the present embodiment, the primary transmission wheel set 4000 further includes a primary transmission gear shaft 4200, and the primary transmission gear shaft 4200 is coaxially connected to the primary transmission gear 4100.

Referring to fig. 18 and 28, in the transmission system provided in the present embodiment, the primary transmission gear shaft 4200 includes an input end 4210, an output gear portion 4220, and a support shaft 4230, wherein the input end 4210 is connected to the center insert 4120, the output gear portion 4220 is located between the input end 4210 and the support shaft 4230, the support shaft 4230 has a diameter smaller than the diameters of the output gear portion 4220 and the input end 4210, the support shaft 4230 is connected to the first needle bearing 4240, and an outer diameter of the first needle bearing 4240 is smaller than a tip circle diameter of the output gear portion 4220. According to the transmission system provided by the embodiment, the support shaft 4230 is designed at the end part of the primary transmission gear shaft 4200, the diameter of the support shaft 4230 is smaller, the needle bearing with the relatively smaller diameter is connected to the support shaft 4230, and the transmission end of the primary transmission gear shaft 4200 is supported through the needle bearing, so that the problem that the primary transmission gear shaft 4200 is seriously abraded on one side in the transmission process due to the suspension state is solved, the transmission of the transmission system is more stable, and the problem of abrasion on one side of the primary transmission gear shaft in the transmission process is reduced.

In the transmission system provided by the present embodiment, as shown in fig. 18, the input end 4210 and the center insert 4120 are connected by a spline arranged on the surface of the input end 4210, so that the circumferential bonding force between the center insert 4120 and the outer ring tooth portion 4110 is more uniform, and the coaxiality is better. It will be appreciated by those skilled in the art that a spline connection may be substituted by a keyway.

In the transmission system provided in the present embodiment, referring to fig. 14 and 18, bearings are respectively provided on the input ends 4210 on both sides of the central insert 4120, and the bearings are located at least partially inside the outer ring tooth portion 4110. At this time, the outer diameter of the bearing should be smaller than the inner diameter of the outer ring tooth 4110, and the central insert 4120 is arranged on both sides of the central insert 4120, so that the support of the outer ring tooth 4110 by the central insert 4120 is more stable, and meanwhile, the central insert 41is matched with the needle roller bearing on the support shaft 4230, so that both ends and the middle of the whole primary transmission gear shaft 4200 can be well supported, and the problem of one-side wear caused by suspension of the primary transmission gear shaft 4200 in the transmission process is avoided. Adopt the overall structure overall arrangement of outer ring tooth portion 4110, central inserts 4120 and both sides bearing, transmission space that can more reasonable utilization guarantees that the transmission is stable, can prolong the life of one-level transmission pinion 4200.

As shown in fig. 24, the transmission system provided in this embodiment further includes a secondary transmission wheel set 5000 and a middle shaft transmission mechanism 6000, wherein the secondary transmission wheel set 5000 includes a secondary transmission gearwheel 5100 and a secondary transmission pinion 5200 which are coaxially connected, the secondary transmission gearwheel 5100 is engaged with the primary transmission gear shaft 4200, and the secondary transmission pinion 5200 is engaged with the middle shaft transmission mechanism 6000. The transmission system provided by the embodiment transmits power to the middle shaft in a three-stage transmission mode.

Referring to fig. 20 and 21, in the transmission system provided in the present embodiment,

middle shaft transmission mechanism 6000 includes middle shaft 6100, torque sensor 6300, chain wheel positioning sleeve 6200, middle shaft gear 6400, first isolator 6500 and second isolator 6600, etc., wherein:

a middle shaft 6100, two ends of which are respectively connected with a crank and a pedal, can receive power input through crank structures at the two ends and transmit the power input to a chain wheel positioning sleeve 6200 through a torque sensor 6300, and further transmit the power input to a chain wheel on the chain wheel positioning sleeve 6200 to drive a rear shaft to rotate so as to drive the bicycle to move forward;

the torque sensor 6300 is fixedly mounted on the middle shaft 6100, the torque sensor 6300 can sense a torque signal transmitted to the crankset positioning sleeve 6200 by the middle shaft 6100 and send the torque signal to the controller, and the controller controls the output power of the motor assembly 2000 in the centrally-mounted motor according to the magnitude of the sensed signal;

one end of the chain wheel positioning sleeve 6200 is connected with the torque sensor through the first one-way clutch 6500, the other end of the chain wheel positioning sleeve 6200 is fixedly connected with the chain wheel, the clutch transmission effect between the chain wheel positioning sleeve 6200 and the torque sensor 6300 is achieved through the first one-way clutch 6500, and the situation that when the middle shaft 6100 stops rotating due to the control of a riding person, the middle shaft 6100 continues to rotate due to the fact that a transmission system of the middle motor continues to rotate due to the rotation inertia is avoided, so that the safety of the riding person is protected;

the middle shaft gear 6400 is connected to the chain wheel positioning sleeve through a second isolator 6600; and the middle shaft gear 6400 is meshed with the secondary drive pinion 5200, the clutch transmission action between the chain wheel positioning sleeve 6200 and the middle shaft gear 6400 can be realized through the second one-way clutch 6600, when the middle motor cannot assist to advance due to power failure, electricity exhaustion, transmission failure or manual operation (such as manually turning off the middle motor or changing the power-assisted mode of the middle motor), and the like, a rider can continue to ride, and the middle shaft 6100, the chain wheel positioning sleeve 6200 and the transmission gear structure of the transmission system are separated from transmission through the second one-way clutch 6600 in the riding process, so that on one hand, the damage to the transmission system can be avoided, on the other hand, the riding pressure and burden of the rider can be reduced, and the riding at the moment is more labor-saving.

It can be known by those skilled in the art that when the primary transmission wheel set 4000 and the secondary transmission wheel set 5000 are not used in the transmission system, the motor assembly 2000 can also directly drive the middle shaft gear 6400, that is, when the transmission system provided by the present embodiment is adjusted from three-stage transmission to one-stage transmission, the middle shaft can also be driven, and the transmission requirement of the middle motor can be met. Similarly, those skilled in the art can adjust the transmission system provided by the present embodiment from three-stage transmission to two-stage transmission or four-stage transmission.

The transmission system provided by the embodiment can solve the problem that when the middle motor cannot assist to advance due to reasons such as power failure, electricity exhaustion, transmission failure or manual operation (for example, manual operation is used for closing the middle motor or the boosting mode of the middle motor is changed), a rider can continue to ride, and the middle shaft 6100 and the chain wheel positioning sleeve 6200 are separated from the transmission gear structure of the transmission system through the second isolator 6600 in the riding process, so that on one hand, the transmission system can be prevented from being damaged, and on the other hand, the riding pressure and the riding burden of the rider can be reduced because any transmission gear of the transmission system is not reversely driven to be combined in the riding process, so that the riding at the moment is more labor-saving.

As shown in fig. 22 and 23, in the transmission system provided in the present embodiment, the middle shaft gear includes a gear portion 6410, a support portion 6420 and a transmission portion 6430, wherein:

the gear part 6410 is positioned at the outer side and is used for meshing transmission with other gears (such as a secondary transmission big gear 5100);

a support portion 6420 located at the inner side of the gear portion 6410 in the radial direction, for connecting with the chain wheel positioning sleeve 6200 through the third ball bearing 6003, where the support portion 6420 can provide stable support for the gear 6410, and ensure stable transmission of the gear 6410;

the transmission portion 6430 is located on one side of the support portion 6420 in the axial direction, and is used for being connected with the chain wheel positioning sleeve 6200 through the second one-way clutch 6600, and the transmission portion 6430 realizes clutch transmission between the gear 6410 and the chain wheel positioning sleeve 6200 under the action of the second one-way clutch 6600.

The transmission system provided by the embodiment improves the structure of the central shaft gear, so that the structure is obviously different from the conventional gear structure, and the stress function of the supporting part is separated from the transmission function of the transmission part, so that the direct stress support transmission of the second isolator is avoided.

Further referring to fig. 21, the present embodiment provides a transmission system in which the gear portion 6410, the support portion 6420, and the transmission portion 6430 form an L-shaped layout, and in the axial direction, the transmission portion 6430 is located outside the support portion 6420 and is structurally closer to the crankset connection structure 6700, and the support portion 6420 is located closer to the annular step structure 6210 of the crankset positioning sleeve 6200, so that the structural layout is reasonable, and the transmission of power is closer to the crankset position, and the transmission of power is more stable.

The crankset positioning sleeve 6200 is provided with a ring-shaped step structure 6210, wherein the first one-way clutch 6500 is provided in the ring-shaped step structure 6210, the second one-way clutch 6600 is located close to the ring-shaped step structure 6210, and the outer diameter of the transmission portion 6430 does not exceed the outer diameter of the ring-shaped step structure 6210; thereby the whole structure is reasonable and compact in layout and occupies small space.

The inner portion of the crankset positioning sleeve 6200 is connected with the central shaft 6100 through two needle bearings which are correspondingly located at two sides of the support portion, the needle bearings are smaller in structural size, so that the size requirement on the crankset positioning sleeve 6200 is reduced, and meanwhile, the two needle bearings are arranged at two sides of the support portion 6420, so that a more stable support effect can be provided for the support portion 6420.

The two needle bearings are a second needle bearing 6001 and a third needle bearing 6002, respectively, in which the second needle bearing 6001 is located outside the third needle bearing 6002, and the third needle bearing 6002 is connected to the torque sensor 6300, and is correspondingly provided in a stepped shape at the connection position of the torque sensor 6300, so that the structure can be made more compact.

The third needle bearing 6002 has a larger inner diameter than the second needle bearing 6001, so that the entire transmission system can be assembled more easily in a direction from small to large.

The torque sensor 6300 is fixedly connected with the middle shaft 6100 through a spline; the middle shaft 6100 is a hollow pipe shaft, and two ends of the middle shaft 6100 are respectively connected with a crank.

As shown in fig. 27-29, the embodiment of the present invention provides a further centrally-mounted motor, which includes the rotor core 2200, the rotating shaft 2300, the rotor, the primary transmission gear 4100, the primary transmission gear 4200, the middle shaft transmission mechanism 6000 or the transmission system provided by the above embodiments, wherein the rotating shaft 2300 is installed on the rotor core 2200.

The mid-motor that this embodiment provided, because of used breach dislocation arrangement's rotor core 2200 to reduce or eliminate because of the unanimous beat problem that leads to the pivot to impress behind the rotor core of breach position, make motor and mid-motor rotate more steadily, and because the design that separates the groove reduces substantially or even eliminated the push-in force completely, overcome the problem that the recess leads to the lifting surface of a rotating shaft face to reduce simultaneously, and use the induction magnet steel that interference fit connects to lead to the flank of tooth to warp.

In the middle motor provided by this embodiment, due to the design of the partition groove of the rotating shaft 2300, when the tooth-shaped portion of the rotating shaft is pressed into the rotating shaft mounting hole of the rotor core, the non-meshing region bears the impact force, so that the deformation generated by the tooth surface is not transmitted to the meshing region, thereby ensuring that the tooth shape of the meshing region is not changed. And simultaneously, the utility model provides a recess has also been overcome in the pivot and the lifting surface area that leads to the pivot terminal surface reduces and use the induction magnet steel that interference fit connects to lead to the problem of flank of tooth deformation.

In the centrally-mounted motor provided by this embodiment, the rotating shaft 2300 of the rotor is connected to the rotor core 2200 in an interference fit manner, and the problem of jumping after the rotating shaft is pressed into the rotor core due to the consistent position of the notch is reduced or eliminated by the notch arrangement manner of the core stamped steel 2210 on the rotor core 2200.

In the middle-mounted motor provided by this embodiment, the supporting shaft 4230 is designed at the end of the primary transmission gear shaft 4200, the diameter of the supporting shaft 4230 is smaller, the needle bearing with a relatively smaller diameter is connected to the supporting shaft 4230, and the transmission end of the primary transmission gear shaft 4200 is supported by the needle bearing, so that the problem that the primary transmission gear shaft 4200 is severely abraded at one side in the transmission process due to being in a suspended state is solved, the transmission of a transmission system is more stable, and the problem of abrasion at one side of the primary transmission gear shaft in the transmission process is reduced.

In the mid-set motor provided by the embodiment, the rotating shaft 2300 is adopted to directly drive the first-stage transmission gear 4100, so that the rotating speed of the rotating shaft 2300 is high, and the first-stage transmission gear 4100 made of an integral metal material has large moment of inertia, thereby causing energy loss; the primary transmission gear 4100 made of non-metallic materials has the problems of large contact surface stress and incapability of meeting the transmission requirement of support strength; therefore, the central insert 4120 made of the metal material and the outer ring tooth portion 4110 made of the non-metal material are adopted in the embodiment, and the width of the outer ring tooth portion 4110 is larger than that of the central insert 4120, so that on one hand, a larger contact area between the outer ring tooth portion 4110 and the rotating shaft 2300 is ensured, the contact stress to the outer ring tooth portion 4110 is reduced, on the other hand, the integral rotational inertia of the central insert 4120 and the outer ring tooth portion 4110 is lower, the energy loss in the transmission process is reduced, and on the other hand, the requirement for the transmission torque can be met due to the fact that the size of the central insert 4120 made of the metal material is smaller.

The embodiment further provides an electric bicycle, which includes the rotating shaft 2300 provided by the above embodiment, or the detecting system provided by the above embodiment, or the transmission system provided by the above embodiment, or the middle motor provided by the above embodiment, and corresponding beneficial effects are not described again.

As shown in fig. 30-32, the embodiment of the present invention further provides an applied rotary transformer's middle motor, which includes a motor assembly 2000, a main casing 1000, a transition casing 1200, a motor cover 1100 and a rotary transformer 3000, wherein:

the motor assembly 2000 comprises a stator 2100, a rotor and a rotating shaft 2300A, wherein the rotating shaft 2300A comprises a rotor connecting part 2340, a power output end 2350 and a rotary transformer mounting end 2360, the rotor connecting part 2340 is positioned between the power output end 2350 and the rotary transformer mounting end 2360, and a rotor core 2200 of the rotor is connected to the rotor connecting part 2340;

a stator mounting portion 1010 for accommodating the stator 2100 is arranged in the main chassis 1000, the stator mounting portion 1010 is separated from the interior of the main chassis 1000 by a partition 1020, an opening of the stator mounting portion 1010 faces outward, a rotary mounting end 2360 of the rotating shaft 2300A extends out from the opening of the stator mounting portion 1010 in an outward direction, and a power output end 2350 of the rotating shaft 2300A penetrates through the partition 1020 to extend in the inward direction and is positioned in the main chassis 1000;

the transition housing 1200 is butted with an opening of the stator mounting portion 1010 of the main housing 1000 to form a motor mounting cavity 1001, the transition housing 1200 is provided with a shaft hole 1210 allowing the rotation shaft to pass through, and the rotation transformer mounting end 2360 is located outside the shaft hole 1210;

the motor cover 1100 is connected to the transition shell 1200 outside the shaft hole 1210 to form a rotary transformer mounting cavity 1002 outside the shaft hole 1210 and receive the rotary transformer mounting end 2360 therein;

resolver 3000 is located in the resolver mounting cavity and includes a resolver stator 3100 and a resolver rotor 3200, wherein the resolver rotor 3200 is mounted at a resolver mounting end 2360.

The in put motor that this embodiment provided uses resolver 3000 synchronous rotation under the drive of rotor to can real-time detection go out the operating condition of rotor, thereby make in put the motor more accurate to motor element's control. The mid-motor that this embodiment provided, through main chassis 1000, transition casing 1200, motor lid 1100 three butt joint has formed motor installation cavity 1001 and the rotary transformer installation cavity 1002 that is independent of the inside transmission cavity 1003 of motor chassis 1000, thereby be convenient for motor element 2000, the assembly of pivot 2300A and resolver 3000, and through transition casing 1200 with motor installation cavity 1001 with the mutual isolation of rotary transformer installation cavity 1002, thereby can keep apart resolver 3000 and motor element 2000, prevent between the two at pivoted in-process electromagnetic interference. In the middle-mounted motor in this embodiment, the main chassis 1000 is in butt joint with the transition housing 1200, and then the transition housing 1200 is in butt joint with the motor cover 1100, and the rotation transformer mounting cavity 1002 is constructed in a butt joint manner of the transition housing 1200 and the motor cover 1100, so that the rotation transformer 3100 can be conveniently fixed on the transition housing 1200 or the motor cover 1100.

In this embodiment, the walls of the main chassis 1000 and the transition chassis 1200 are respectively provided with a lead channel, which is communicated with the internal of the rotary transformer installation cavity and the main chassis, and a lead is arranged in the lead channel to connect the rotary transformer stator to the circuit board in the main chassis. Through the design structure of the lead channel, the safety requirement of the centrally-mounted motor can be ensured.

The embodiment of the utility model also provides a middle motor applying the rotary transformer, which comprises a motor assembly 2000, a main machine shell 1000, a transition shell 1200, a motor cover 1100 and the rotary transformer 3000,

the transition housing 1200 is connected with the stator mounting portion 1010 of the main housing 1000 to form a motor mounting cavity 1001, the transition housing 1200 is provided with a shaft hole 1210 allowing the rotating shaft to pass through, and the rotating transformer mounting end 2360 is located outside the shaft hole 1210;

the motor cover 1100 is butted with an opening of the stator mounting portion 1010 of the main chassis 1000 to form a rotation mounting cavity 1002 outside the shaft hole 1210 and receive the rotation mounting end 2360 therein;

resolver 3000 is located in the resolver mounting cavity, and includes resolver stator 3100 and resolver rotor 3200, where resolver rotor 3200 is mounted at resolver mounting end 2360.

The in put motor that this embodiment provided uses resolver 3000 synchronous rotation under the drive of rotor to can real-time detection go out the operating condition of rotor, thereby make in put motor more accurate to motor element's control. The mid-motor that this embodiment provided, through main chassis 1000, transition casing 1200, motor lid 1100 three butt joint has formed motor installation cavity 1001 and the rotary transformer installation cavity 1002 that are independent of the inside transmission chamber 1003 of motor chassis 1000, thereby be convenient for motor element 2000, the assembly of pivot 2300A and resolver 3000, and through transition casing 1200 with motor installation cavity 1001 with the mutual isolation of rotary transformer installation cavity 1002, thereby can keep apart resolver 3000 and motor element 2000, prevent between the two at pivoted in-process electromagnetic interference. In the middle-mounted motor in this embodiment, what is adopted is a mode in which the main chassis 1000 is in butt joint with the motor cover 1100, and a mode in which the transition housing 1200 is arranged is used to divide a cavity formed by the main chassis 1000 and the motor cover 1100 into the independent rotation mounting cavity 1002 and the independent motor mounting cavity 1001, so that the rotation stator 3100 can be conveniently fixed on the transition housing 1200 or the motor cover 1100.

In this embodiment, a lead channel is disposed on the wall of the main casing 1000, the lead channel connects the rotary transformer mounting cavity 1002 and the transmission cavity 1003 inside the main casing 1000, and a lead is disposed in the lead channel to connect the rotary transformer stator to the circuit board 7100 inside the main casing. Through the design structure of the lead channel, the safety requirement of the centrally-mounted motor can be ensured.

The above examples provide two embodiments of the center motor using the resolver, and the resolver of both embodiments is installed at the non-power output end of the rotating shaft 2300A, since the lead of the resolver stator needs to be connected to the circuit board 7100 inside the center motor to transmit the sensing signal to the circuit board 7100, and the circuit board 7100 is generally a transmission cavity 1003 disposed inside the main housing 1000, but the transmission cavity 1003 is not connected to or adjacent to the resolver installation cavity 1002, so that the lead needs to be connected to the circuit board through a lead channel. Further optimization of the above two embodiments is illustrated below:

in this embodiment, the stator mounting portion 1010 and the partition 1020 may be integrally formed on the main chassis 1000, or may be connected to the main chassis 1000 in a separate structure.

In this embodiment, a first fixing structure is disposed on the transition housing 1200 outside the shaft hole 1210 to fix the rotating stator 3100. The mode of fixing the resolver stator 3100 through the transition housing 1200 can make the resolver closer to the motor mounting cavity 1001, thereby reducing the length of the rotating shaft 2300A, making the overall structure more compact, and making the resolver stator 3100 more convenient to mount and fix.

In this embodiment, the first fixing structure includes an annular rib 1220 disposed on the transition casing 1200 and coaxially disposed with the shaft hole 1210, a fixing block 1230 is disposed outside the annular rib 1220, and the fixing block 1230 is connected to the transition casing 1200 and abuts against an outer portion of the rotational stator 3100. The annular rib 1220 provides a reference for fixing the rotational stator 3100, and since the transition housing 1200 and the main housing 1000 are directly connected, the annular rib 1220 and the motor assembly 2000 are more coaxial, so that the rotational stator 3100 and the rotational rotor 3200 mounted on the rotating shaft 2300A are more assembled. Annular ribs 1220 may further increase the structural strength of transition housing 1200, thereby increasing the ability of transition housing 1200 to resist deformation.

In this embodiment, the fixing block 1230 has an arc-shaped structure, and has the same radian as the abutting part of the rotational stator 3100, and the rotational stator 3100 is abutted by the fixing block 1230 having the arc-shaped structure, so that the assembly accuracy of the rotational stator 3100 can be ensured to be better.

In this embodiment, an annular groove 3120 is provided at the abutting portion of the rotary transformer 3100, and the fixing block 1230 has a radian matching with the annular groove 3120. The fixing block 1230 can be clamped in the annular groove 3120 on the rotary transformer 3100, so that the rotary transformer 3100 can be fixed and centered after the fixing block 1230 is connected with the rotary transformer 3100.

In this embodiment, a bearing installation chamber 1240 is provided in the transition housing 1200 inside the shaft hole 1210, and a bearing is installed in the bearing installation chamber 1240 and is fitted to the rotating shaft 2300A. Bearing mounting chamber 1240 is also of annular configuration, similar to the configuration of annular rib 1220, and may further improve the structural strength of transition housing 1200. Meanwhile, the bearing is installed in the bearing installation chamber 1240, which can provide support for the rotating shaft 2300A, thereby making the structural layout more reasonable.

In this embodiment, a second fixing structure may be optionally provided inside the motor cover 1100 to fix the rotating stator. The second fixing structure functions substantially the same as the first fixing structure, and fixes the rotary transformer 3100, except that the second fixing structure is disposed inside the motor cover 1100, and the first fixing structure is disposed on the transition case 1200. The specific design of the second fixing structure may refer to the first fixing structure.

In this embodiment, the transition shell 1200 is made of a magnetic isolation material; thereby enabling better isolation of the motor assembly 2000 from the resolver 3000 and reducing or eliminating electromagnetic interference therebetween.

In this embodiment, the power output 2350 is machined with gears; specifically, reference may be made to the structural design of the rotating shaft 2300 in the above embodiments, and details are not described herein. When the power output end 2350 directly processes a gear, the transmission effect of the middle motor can be better, the structure is more compact, the cost can be reduced, and the transmission efficiency can be improved.

In this embodiment, the end surface of the rotation-changing mounting end 2360 is connected to a third fixing structure 2361 to fix the rotation-changing rotor 3200. The third securing structure 2361 is a nut and the nut is sized to be larger than the end face diameter of the threaded mounting end 2360.

In this embodiment, the ring direction of the inner wall of the stator mounting portion 1010 is provided with two or three ring-shaped grooves 1011, and the ring-shaped grooves 1011 are filled with colloid, so that after the stator core is mounted in the mounting cavity, the colloid is connected with the stator core. The stator core is connected to the stator mounting portion 1010 of the main case 1000 in a glue injection mode through the annular groove 1011, so that the stator core can be well fixed, and the stator core can be kept fixed in the operation process of the motor assembly 2000. In this embodiment, instead of the annular groove 1011, a multi-segment arc groove may be used, or the arc groove and the annular groove 1011 may be used in combination, so as to fix the stator core. Those skilled in the art will appreciate that the multi-segment arcuate slot pattern is better able to overcome circumferential movement of the stator core.

In this embodiment, the connection positions of the annular groove 1011 and the arc-shaped groove far away from the opening and the inner wall of the stator mounting portion 1010 are set to be chamfers, fillets or inclined planes; thereby further facilitating assembly of the stator core into the stator mounting portion 1010.

In this embodiment, the surface in annular groove 1011, the arc recess is established to the friction surface to after the injecting glue, the colloid is bigger with the area of contact of recess, and fixed effect is also better.

In this embodiment, the external portion of the main chassis 1000 is further provided with a heat dissipating rib 1030, the heat dissipating rib 1030 is perpendicular to the axial direction of the rotating shaft 2300A and corresponds to the position of the stator, and the stator is directly connected to the inner wall of the main chassis 1000, so that the heat of the stator can be conducted away in time. In the implementation process, heat dissipation ribs may also be disposed at corresponding positions of other heat generating structures of the main chassis 1000, and the effect of the heat dissipation ribs is substantially the same as that of the heat dissipation ribs 1030 in this embodiment.

In this embodiment, the top edge of the heat dissipating ribs 1030 is aligned with the height of the outer surface of the main chassis 1000 where the heat dissipating ribs 1030 are not disposed; thereby can guarantee that heat dissipation muscle 1030 and main chassis 1000 surface have unanimous external dimension, avoid heat dissipation muscle 1030 protrusion to meet the damage of leading to heat dissipation muscle 1030 when external collision in main chassis 1000 surface.

In this embodiment, the arrangement direction of the heat dissipation ribs 1030 is the same as the direction of the middle-placed motor advancing along with the bicycle, so that the bicycle advances, and meanwhile, the airflow can pass through the heat dissipation ribs, and the heat dissipation effect is improved.

The central motor provided by this embodiment and having the resolver mounted at the non-power output end of the rotating shaft may further use a stator core, a rotating shaft, a primary transmission gear shaft, a central motor transmission mechanism, and the like, and specific reference may be made to the related explanations of the above embodiments, and details are not repeated here.

As shown in fig. 33 to 36, the present embodiment further provides a central motor using a rotary transformer, where the rotary transformer in the present embodiment is located at a power output end of the motor assembly 2000, and the central motor provided in the present embodiment includes the motor assembly 2000, the main chassis 1000, and the rotary transformer 3000, where:

the motor assembly 2000 comprises a stator 2100, a rotor and a rotating shaft 2300B, wherein the rotating shaft 2300B comprises a rotor connecting end 2370, a power output part 2380 and a rotary transformer mounting end 2360, the power output part 2380 is positioned between the rotary transformer mounting end 2360 and the rotor connecting end 2370, and the rotor is mounted on the rotor connecting end 2370;

the inside of the main chassis 1000 is divided into a motor mounting cavity 1001 and a transmission cavity 1003 by a partition plate, the rotating shaft 2300B passes through a through hole on the partition plate, and the rotor connection end 2370 of the stator 2100, the rotor and the rotating shaft 2300B is positioned in the motor mounting cavity 1001; the power output part 2380 and the rotary transformer mounting end 2360 of the rotating shaft 2300B are positioned in the transmission cavity 1003;

the rotary transformer 3000 is located in the transmission cavity 1003, and includes a rotary stator 3100 and a rotary rotor 3200, wherein the rotary rotor 3200 is mounted at a rotary mounting end 2360 of the rotary shaft 2300B, and the rotary stator 3100 is fixedly connected in the main chassis 1000 through a first fixing structure.

In the mid-motor provided by the embodiment, the rotary transformer mounting end 2360 is arranged at the outer side of the power output portion 2380 of the rotating shaft 2300B and is used for mounting the rotary transformer 3200 of the rotary transformer 3000, so that the problem that the rotating shaft 2300 deforms on the tooth surface when being pressed into the rotor core 2200 due to the fact that the induction magnetic steel is mounted at the power output end of the rotating shaft 2300 in the prior art (as shown in fig. 29) is avoided, and the rotating shaft 2300 is directly connected onto the rotating shaft 2300B through the rotary transformer 3000, so that the rotation of the rotating shaft 2300B can be synchronous with the rotation of the rotating shaft 2300B, and the induction signal detected by the induction magnetic steel is more accurate than that detected by the induction magnetic steel.

In the middle motor provided by this embodiment, because the rotary transformer 3000 is disposed in the transmission cavity 1003 of the main chassis 1000, and the circuit board 7100 is also disposed in the transmission cavity 1003, the rotary transformer 3000 can be directly connected to the circuit board 7100, and there is no need to connect the rotary transformer to the non-power output end of the rotating shaft in the above embodiments, and a complex structural design of a routing channel for routing the lead of the rotary transformer stator is required.

The centrally-mounted motor provided by the embodiment further comprises a circuit board 7100, the circuit board 7100 is arranged in the transmission cavity 1003, and the rotary transformer 3100 is connected with the circuit board 7100 through a lead.

The centrally-mounted motor provided by the embodiment further comprises a motor cover 1100 connected to a motor installation cavity 1001 of the main chassis 1000;

the motor cover 1100 is provided with a first bearing installation chamber 1110 therein, and the rotation shaft 2300B is coupled to the first bearing installation chamber 1110 through a first ball bearing 1111. A second bearing installation chamber 1022 is provided on the partition 1020 around the inner side of the through-hole, and the rotary shaft 2300B is coupled in the second bearing installation chamber 1022 through a second ball bearing 1023. The two bearing chambers and the internal bearings can provide support for the shaft 2300B.

The centrally-mounted motor provided by this embodiment further includes a main housing cover 1300, which is connected to the transmission cavity of the main housing 1000;

a first fixing structure is disposed at a position corresponding to the rotation-transformation mounting end 2360 inside the main body cover 1300 to fix the rotation-transformation stator 3100.

In this embodiment, the first fixing structure includes an annular rib 1220 disposed inside the main body cover 1300 and coaxially disposed with the shaft hole 1210, a fixing block 1230 is disposed outside the annular rib 1220, and the fixing block 1230 is connected inside the main body cover 1300 and abuts against an outside of the rotational stator 3100. The annular rib 1220 provides a reference for fixing the rotation stator 3100, and since the main cover 1300 and the main housing 1000 are directly connected, the coaxiality of the annular rib 1220 and the motor assembly 2000 is also improved, and the rotation stator 3100 and the rotation rotor 3200 mounted on the rotating shaft 2300B are assembled better. The annular rib 1220 may further improve the structural strength of the main body cover 1300, thereby improving the deformation resistance of the main body cover 1300.

In this embodiment, an annular groove 3120 is provided at the abutting portion of the rotary transformer 3100, and the fixing block 1230 has a radian matching with the annular groove 3120. The fixing block 1230 can be clamped in the annular groove 3120 on the rotary transformer 3100, so that after the fixing block 1230 is connected with the rotary transformer 3100, the fixing and centering effects on the rotary transformer 3100 can be achieved.

In this embodiment, the outside of the main chassis 1000 is further provided with a heat dissipating rib 1030, the heat dissipating rib 1030 is perpendicular to the axial direction of the rotating shaft 2300A and corresponds to the position of the stator, and the stator is directly connected with the inner wall of the main chassis 1000, so that the heat of the stator can be conducted out in time. In the implementation process, the heat dissipation ribs may be disposed at corresponding positions of other heat generating structures of the main chassis 1000, and the effect of the heat dissipation ribs is substantially the same as that of the heat dissipation ribs 1030 in this embodiment.

In this embodiment, the top edge of the heat dissipating rib 1030 is aligned with the outer surface of the main chassis 1000 without the heat dissipating rib 1030; thereby can guarantee that heat dissipation muscle 1030 and main chassis 1000 surface have unanimous external dimension, avoid heat dissipation muscle 1030 protrusion to meet the damage of leading to heat dissipation muscle 1030 when external collision in main chassis 1000 surface.

The middle motor provided by this embodiment and provided with the resolver at the power output end of the rotating shaft may further use a stator core, a rotating shaft, a first-stage transmission gear shaft, a middle motor transmission mechanism, and the like, and specific reference may be made to the relevant explanations of the above embodiments, and details are not repeated here.

The technical features of the above embodiments can be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the above embodiments are not described, but should be considered as the scope of the present specification as long as there is no contradiction between the combinations of the technical features.

The above examples only represent some embodiments of the present invention, and the description thereof is more specific and detailed, but not to be construed as limiting the scope of the present invention. It should be noted that, for those skilled in the art, without departing from the spirit of the present invention, several variations and modifications can be made, which are within the scope of the present invention. Therefore, the protection scope of the present invention should be subject to the appended claims.

Claims

1. A centrally-mounted motor comprises a rotating shaft (2300) and a rotor core, wherein the rotating shaft is installed in a shaft hole of the rotor core, the rotating shaft (2300) comprises a shaft-shaped part (2310) and a tooth-shaped part (2320), a tooth surface extending to the end is machined on the surface of the tooth-shaped part (2320), the tooth-shaped part (2320) comprises a meshing area (2321) and a non-meshing area (2322), the meshing area (2321) is connected with the shaft-shaped part (2310), the non-meshing area (2322) is located at the free end of the rotating shaft (2300), and a circular-cut partition groove (2323) is arranged on the tooth surface of the non-meshing area (2322) or a circular-cut partition groove (2323) is arranged on the tooth surface at the junction of the meshing area (2321) and the non-meshing area (2322).

2. The mid-set electric machine according to claim 1, characterised in that the depth of the breaking grooves (2323) does not exceed the height of the tooth flanks.

3. The mid-set motor according to claim 1, wherein the tooth surface is a helical tooth or a straight tooth.

4. The centrally placed electric motor according to claim 1, characterized in that a recess (2324) is provided on the end surface of the rotating shaft (2300) at one end of the shaft-shaped portion (2310), an induction magnetic steel (2345) is installed in the recess (2324),

optionally, the groove (2324) is circular and is provided with an inner conical surface at the center of the groove (2324),

optionally, the diameter of the recess (2324) is smaller than the diameter of the root circle,

optionally, the induction magnetic steel is also circular, and the diameter of the induction magnetic steel (2345) is larger than that of the groove (2324), so that the induction magnetic steel (2345) is installed in the groove (2324) in a clearance fit manner;

or the induction magnetic steel (2345) is connected in the groove (2324) through glue.

5. The mid-motor according to claim 4, characterized by further comprising a circuit board (7100), a sensing element (7110), the position of the sensing element (7110) is corresponding to the position of the sensing magnetic steel (2345), the sensing element (7110) is connected with the circuit board (7100) and sends a sensing signal to the circuit board (7100),

optionally, the center of the induction element (7110) and the induction magnetic steel (2345) are positioned on the same axis,

optionally, the inductive element (7110) is a magnetic chip.

6. The centrally-mounted motor according to claim 1, further comprising a primary transmission wheel set (4000), wherein the primary transmission wheel set (4000) comprises a primary transmission gear (4100), the primary transmission gear (4100) is engaged with the engagement area (2321) of the rotating shaft (2300),

optionally, the primary transmission gear (4100) comprises a central insert (4120) and an outer ring tooth part (4110), the center of the central insert (4120) is provided with a shaft hole, the outer ring tooth part (4110) is connected to the outer circumference of the central insert (4120) and is coaxially arranged, the width of the outer ring tooth part (4110) in the axial direction is larger than that of the central insert (4120) in the axial direction, and both ends of the outer ring tooth part (4110) in the axial direction exceed the central insert (4120); the central insert (4120) is made of a metal material, the outer ring tooth part (4110) is made of a non-metal material,

optionally, the outer circumferential surface of the central insert (4120) is provided with a reinforcement structure; the reinforcing structure is protruded or recessed on the surface of the outer circumference,

optionally, the reinforcing structure is reinforcing teeth (4121), knurls or splines arranged around the outer circumference of the central insert (4120),

optionally, the reinforcement tooth (4121) is split into at least three segments in the axial direction,

alternatively, the tooth crest of the reinforcing tooth (4121) is an arc surface or a surface with an obtuse included angle,

optionally, the number of the splines is not less than 4, the spline modulus is not less than 0.25,

optionally, the outer ring toothing (4110) is injection molded on the outer circumference of the central insert (4120),

optionally, the primary transmission wheel set (4000) further comprises a primary transmission gear shaft (4200), the primary transmission gear shaft (4200) is coaxially connected with the primary transmission gear (4100),

optionally, the primary transmission gear shaft (4200) comprises an input end (4210), an output gear portion (4220) and a support shaft (4230), wherein the input end (4210) is connected with the central insert (4120), the output gear portion (4220) is located between the input end (4210) and the support shaft (4230), a diameter of the support shaft (4230) is smaller than diameters of the output gear portion (4220) and the input end (4210), the support shaft (4230) is connected with a first needle bearing (4240), and an outer diameter of the first needle bearing (4240) is smaller than a tip circle diameter of the output gear portion (4220),

optionally, the input end (4210) and the central insert (4120) are connected by a spline or keyway arranged on the surface of the input end (4210),

optionally, bearings are provided on the input end (4210) on both sides of the central insert (4120) and are located at least partially inside the outer ring teeth.

7. The centrally mounted electric machine according to claim 6, further comprising a secondary transmission wheel set (5000) and a central shaft transmission mechanism (6000), wherein the secondary transmission wheel set (5000) comprises a secondary transmission gearwheel (5100) and a secondary transmission pinion (5200) which are coaxially connected, the secondary transmission gearwheel (5100) meshing with the primary transmission gear shaft (4200), and the secondary transmission pinion (5200) meshing with the central shaft transmission mechanism (6000).

8. The centrally-mounted motor according to claim 1, wherein the rotor core comprises a plurality of groups of core laminations, each group of core laminations comprises at least one core lamination (2210), the number of poles of the core laminations (2210) is N, M notches (2211) are arranged in a shaft hole (2212) of each core lamination (2210), M is not an integral multiple of N, after the plurality of groups of core laminations (2210) are laminated to form the rotor core, projections of the notches (2211) of at least one group of core laminations and the notches (2211) of other groups of core laminations on a plane where any core lamination (2210) is located are at least partially staggered,

optionally, the difference of the rotation angles between two adjacent sets of core laminations (2210) is K, where K =360 × N/N, and N is a natural number less than N; the rotation angle difference K is not equal to 360 × M/M, M is a natural number less than M, so that notches (2211) of a plurality of groups of iron core punching sheets are spirally arranged on a rotating shaft mounting hole (2220) of the rotor iron core,

alternatively, M is more than or equal to 2, and M gaps are uniformly distributed at the edge of the shaft hole (2212),

alternatively, the travel of the helical shape in the circumferential direction comprises at least 1 circumference,

alternatively, the helical shape is an integer number of circumferences,

optionally, the gap (2211) is triangular, arc-shaped, semi-circular, rectangular or trapezoidal,

optionally, the core stamped steel (2210) comprises a core yoke portion (2213) and core tooth portions (2214) arranged in an array manner around the circumference of the core yoke portion (2213), two ends of the outer edge of each core tooth portion (2214) are respectively provided with pole shoes (2216) extending towards two sides, and a magnetic steel mounting groove (2215) is formed between two adjacent core tooth portions (2214); wherein the iron core tooth part (2214) is of a sector structure with the radius smaller than that of the iron core punching sheet,

optionally, the circle centers of the sector structures of all the core tooth portions (2214) are on the same circle with the axis of the rotor core (2200) as the circle center, and the arrangement direction of each sector structure points to the outside along the connecting line direction of the circle center of the core stamped steel (2210) and the circle center of the core tooth portion (2214); and the middle point of the arc line of the sector structure is positioned on the excircle of the iron core stamped steel (2210) at the same time,

alternatively, the core tooth portion (2214) is connected to the core yoke portion (2213) by a barrier strip (2217), the width of the barrier strip (2217) is smaller than the minimum width of the core tooth portion (2214),

optionally, a circular hole (2218) is arranged on the sector of the iron core tooth part (2214), the distance between the circular hole (2218) and three sides of the sector is equal,

optionally, the core stamped sheets (2210) include open-structure core stamped sheets (2210A) and closed-structure core stamped sheets (2210B), wherein the open-structure core stamped sheets (2210A) are arranged between the closed-structure core stamped sheets (2210B); the pole shoe (2216) of two adjacent iron core tooth parts (2214) of the closed-structure iron core stamped steel (2210B) are connected to form a closed structure.

9. The centrally-mounted motor according to claim 8, characterized in that the closed-structure core stamped piece (2210B) is further provided with a supporting block (2219) at a core yoke portion (2213) between two adjacent magnetic separation strips (2217) so as to position the short side of the magnetic steel.

10. An electric bicycle, characterized in that it comprises a centrally placed electric motor according to any of the preceding claims 1-9.