CN212343518U - External rotor motor - Google Patents

Abstract

The utility model provides an external rotor electric machine, includes stator, relative stator pivoted pivot and centers on the pivot and along with the rotatory rotor of pivot, the stator includes base end cover and iron core winding, the pivot is held including the first end of restraint in the stator and the second that stretches out the stator, the pivot is supported by a bearing subassembly, bearing subassembly comprises first bearing and second bearing, first bearing housing is located the first end of pivot, the second bearing is located the iron core winding, the utility model discloses reduce the interval between two bearings, effectual bearing pivot receives the load and avoid bad such as pivot bending, skew center pin avoid the rotor to produce the production of striking, noise reduction at the pivoted in-process, guarantee the silence effect and the life of motor.

Description

External rotor motor

Technical Field

The utility model relates to the technical field of electric machines, especially, relate to an external rotor electric machine.

Background

The motor is used as the most common power source and is widely applied to various industries. The motor is generally composed of a stator and a rotor rotating relative to the stator, wherein the rotor is provided with permanent magnets, the stator is provided with coils, and when the stator coils are electrified, the stator coils generate a changing magnetic field which interacts with the magnetic field of the permanent magnets of the rotor to push the rotor to continuously rotate and drive a load.

In order to ensure smooth rotation of the rotor and reduce noise and wear, a bearing is usually sleeved on the rotating shaft of the rotor to support the rotation of the rotor. However, in the existing motor, especially in the structure of the micro motor, the bearings are usually disposed at two axial ends of the housing of the motor, that is, approximately at two ends of the rotating shaft, and the rotating shaft may be bent and deformed during the rotation process, so that the noise of the motor is large and the service life of the motor is short.

SUMMERY OF THE UTILITY MODEL

In view of this, the present invention provides an external rotor motor that can effectively solve the above problems.

The outer rotor motor comprises a stator, a rotating shaft and a rotor, wherein the rotating shaft rotates relative to the stator, the rotor surrounds the rotating shaft and rotates along with the rotating shaft, the stator comprises a base end cover and an iron core winding, the rotating shaft comprises a first end constrained in the stator and a second end extending out of the stator, the rotating shaft is supported by a bearing assembly, the bearing assembly comprises a first bearing and a second bearing, the first bearing is sleeved at the first end of the rotating shaft, and the second bearing is located in the iron core winding.

The utility model provides an external rotor motor, including the shell, with the base end cover that the shell is connected, fixed set up in iron core winding in the shell, set up the pivot in iron core winding with rotating and support the bearing assembly of pivot, bearing assembly comprises first bearing and second bearing, first bearing inlays to be located in the base end cover and overlaps and locate the first end of pivot, the second bearing is located iron core winding and overlaps and locate the middle part of pivot, the second end of pivot wear to locate the central authorities of shell and with shell clearance fit.

The utility model discloses the one end of external rotor electric machine's pivot by first bearing support, the middle part by the second bearing support, the other end with shell clearance fit, first bearing and second bearing have reduced the interval between the bearing in traditional motor, the effectual load that bears the weight of the pivot and avoid the pivot is bad such as crooked, skew center pin, avoids the rotor to produce the production of striking, noise reduction at the pivoted in-process, guarantees the utility model discloses the silence effect and the life of motor.

Drawings

Fig. 1 is a perspective assembly view of an outer rotor motor according to an embodiment of the present invention.

Fig. 2 is a sectional view of the outer rotor motor shown in fig. 1.

Fig. 3 is an exploded view of the outer rotor motor shown in fig. 1.

Fig. 4 is another angular view of fig. 3.

Fig. 5 is a further exploded view of the base end cap of the outer rotor motor shown in fig. 3.

Fig. 6 is another angular view of fig. 5.

Detailed Description

The present invention will be described in detail with reference to the accompanying drawings and specific embodiments, so that the technical solutions and the advantages thereof will be more clearly understood. It is to be understood that the drawings are provided for purposes of illustration and description only and are not intended as a definition of the limits of the invention, but the dimensions shown in the drawings are for convenience and are not to be taken as limiting the scale.

As shown in fig. 1 to 4, an external rotor motor according to an embodiment of the present invention includes a housing 10, a stator 20 fixedly connected to the housing 10, a rotating shaft 30 rotatably disposed in the stator 20, and a rotor 40 surrounding the rotating shaft 30 and rotating along with the rotating shaft 30.

As shown in fig. 3, the housing 10 has a cylindrical structure with one open end, and includes an annular axial end surface 12 and a circumferential wall surface 14 extending substantially perpendicularly from an outer edge of the axial end surface 12. A through hole 120 is formed in the center of the axial end face 12 for the rotation shaft 30 to pass through, and is connected with an external load to output torque. Preferably, the aperture of the through hole 120 is slightly larger than the diameter of the rotating shaft 30, and the rotating shaft 30 is in clearance fit with the axial end face 12.

The stator 20 includes a base end cap 22, a shaft seat 24, and a core winding 26. The base end cap 22 covers the open end of the housing 10, i.e. the end of the circumferential wall 14 away from the axial end face 12, and together form a substantially sealed space for installing the core winding 26 and the rotor 40. The base end cap 22 is generally dome-shaped and matches the shape and size of the open end of the housing 10.

As shown in fig. 4, the inner surface of the end of the circumferential wall 14 is recessed in the radial direction to form an annular step 16 for being axially mounted and positioned with the base end cap 22; the end of the circumferential wall 14 is further formed with at least one notch 18 extending radially through the circumferential wall 14 for circumferentially positioning with the base end cap 22. Correspondingly, the base end cover 22 is formed with an annular flange 220 protruding radially outward, and the outer diameter of the flange 220 is equivalent to that of the step 16; the outer edge of the flange 220 is formed with at least one protrusion 222 protruding radially outward.

When the base end cap 22 is inserted into the open end of the housing 10, the flange 220 abuts against the step 16, and the two form a limit in the axial direction; the protrusions 222 are snapped into the corresponding notches 18 to limit the relative rotation between the cover and the housing 10, thereby axially and circumferentially securing the housing 10 to the base end cap 22. Preferably, the number of the protrusions 222 and the notches 18 is plural, and the protrusions and the notches are uniformly spaced along the circumferential direction of the base end cover 22 or the circumferential wall surface 14. In other embodiments, the notch 18 may be formed by the base end cap 22, and the protrusion 222 formed in the circumferential wall 14 is correspondingly snapped into place with the notch 18.

Referring to fig. 5 and fig. 6, the shaft seat 24 is a circular tube structure, the bottom end 240 is embedded in the base end cover 22, and the main body 242 extends from the center of the base end cover 22 toward the housing 10 along the axial direction. The shaft seat 24 has a shaft hole 244 formed therein and extending therethrough in the axial direction for being inserted into the rotating shaft 30. The diameter of the rotating shaft 30 is slightly smaller than the inner diameter of the shaft seat 24, so that the rotating shaft 30 and the shaft seat 24 form clearance fit.

In this embodiment, a stepped bore 224 is formed in the base end cap 22 to receive the bottom end 240 of the axle seat 24. The bottom end 240 is contoured to match the stepped bore 224, both of which are axially oriented. In this embodiment, a first bearing hole 246 is formed in the bottom end 240 of the shaft seat 24 around the shaft hole 244, and the first bearing hole 246 is coaxially disposed with the shaft hole 244. The first bearing hole 246 is provided with a first bearing 50 therein, and the first bearing 50 may be a ball bearing, a ceramic bearing, an oil bearing, a sliding bearing, or the like. A sealing cap 28 closes off the outer end of the stepped bore 224 to seal the first bearing 50 within the base end cap 22.

The core winding 26 is sleeved on the main body 242 of the shaft seat 24, and includes a core and a coil winding (not shown) wound on the core. The core winding 26, or the axially upper end 260 of the core, is raised a distance above the top end of the shaft housing 24 so that the portion of the core winding 26 axially projecting upwardly from the shaft housing 24 forms a second bearing hole 248 around the shaft hole 244 on the upper side of the shaft housing 24. The second bearing bore 248 is disposed coaxially with the first bearing bore 246, and the second bearing 52 is disposed within the second bearing bore 248. The second bearing 52 may be a ball bearing, a ceramic bearing, an oil bearing, a sliding bearing, etc., and the first and second bearings 50, 52 may be of the same type or different types.

In this embodiment, the center of the base end cap 22 extends axially outward to form a cylinder 226, and the cylinder 226 surrounds the axle seat 24. The shaft seat 24 extends outwardly from the base end cap 22 by a height substantially greater than the barrel 226, and the body 242 of the shaft seat 24 extends above the barrel 226. The axially lower ends 262 of the core windings 26 rest on the cylinder 226, both of which are axially oriented.

Preferably, a key 249 protrudes from an outer surface of the shaft seat 24, a corresponding key groove 264 is formed on an inner surface of the core winding 26, and the key 249 is inserted into the key groove 264 during assembly, so that the shaft seat 24 and the core winding 26 are circumferentially positioned. In other embodiments, the core winding 26 may protrude to form a key, and the shaft seat 24 may be recessed to form a keyway for the key.

In this embodiment, the cylinder 226 is further sleeved with a circuit board 54, and the circuit board 54 may be connected to the base end cap 22 through a fixing member such as a screw, or may be connected to the base end cap 22 by a snap. The circuit board 54 is provided with a plurality of terminals 56 for connecting the coils of the core winding 26 to an external power source. Correspondingly, a plurality of wiring holes 228 are formed on the base end cap 22, and the wiring terminals 56 are extended from the wiring holes 228.

The rotor 40 is disposed around the stator 20 and includes a rotor shell 42 sleeved on the rotating shaft 30 and a magnet 44 attached to the inside of the rotor shell 42. The rotor 40 magnets 44 are preferably permanent magnets disposed around the core winding 26 with a radial spacing therebetween. The rotor housing 42 is radially spaced from the circumferential wall 14 of the housing 10 to facilitate rotation of the rotor 40. In this embodiment, the rotor housing 42 is fixedly connected to the shaft 30 via a flange 46. The flange 46 is located on the axially upper side of the second bearing 52, and a wear-resistant stopper 58 is preferably provided therebetween.

A first end, i.e., a bottom end 32, of the rotating shaft 30 is rotatably inserted into the first bearing 50; the second end, i.e., the illustrated top end 34, of the shaft 30 passes through the second bearing 52, the flange 46, and the axial end face 12 of the housing 10 in this order and protrudes out of the housing 10 to be connected to a load. In general, the bottom end 32 of the shaft 30 is supported by a first bearing 50, the middle position is supported by a second bearing 52, and the top end 34 is in clearance fit with the housing 10 without contact. The utility model discloses external rotor electric machine's coil is when the circular telegram, the coil circular telegram of iron core winding 26 produce the alternating magnetic field with the magnetic field of rotor 40's magnet 44 is used mutually, promotes rotor 40 and pivot 30 continue to rotate.

The top end 34 of the rotating shaft 30 freely penetrates out of the housing 10 to be connected with a load, that is, the outer rotor motor of the present invention has no bearing on the housing 10, and no contact exists between the rotating shaft 30 and the housing 10, so the housing 10 no longer supports the rotation of the rotor 40, and the vibration of the rotor 40 during the rotation process cannot be directly transmitted to the housing 10. Additionally, the utility model discloses the side by stator 20's iron core winding 26 at axle bed 24 forms second bearing hole 248 to installation bearing 52 forms the support to the middle part of pivot 30, has reduced the interval between the bearing, and the effectual load that bears the weight of the pivot and avoiding pivot 30 is crooked, skew etc. guarantees pivot 30 and axle bed 24, bearing 50, 52's axiality, avoids pivot 30 to produce the production of striking, noise reduction at the pivoted in-process, guarantees the utility model discloses the silence effect and the life of motor.

The above description is only a preferred embodiment of the present invention, the protection scope of the present invention is not limited to the above listed embodiments, any person skilled in the art can obviously obtain simple changes or equivalent substitutions of the technical solutions within the technical scope of the present invention.

Claims (10)

1. The outer rotor motor comprises a stator, a rotating shaft and a rotor, wherein the rotating shaft rotates relative to the stator, the rotor surrounds the rotating shaft and rotates along with the rotating shaft, the stator comprises a base end cover and an iron core winding, the rotating shaft comprises a first end restrained in the stator and a second end extending out of the stator, and the outer rotor motor is characterized in that the rotating shaft is supported by a bearing assembly, the bearing assembly comprises a first bearing and a second bearing, the first bearing is sleeved at the first end of the rotating shaft, and the second bearing is positioned in the iron core winding.

2. The external rotor electric machine of claim 1, wherein the stator further includes a shaft seat mounted on the shaft and located between the first bearing and the second bearing, the shaft seat is in clearance fit with the shaft, and a bottom end of the shaft seat is embedded in the end cover of the base and restrains and fixes the first bearing.

3. The external rotor electric machine according to claim 1 or 2, wherein the second bearing is located off-center from an axial center of the core winding and close to an axial side end of the core winding.

4. The external rotor electric motor of claim 2, wherein one of the inner surface of the core winding and the outer surface of the shaft seat is formed with a key, and the other is formed with a key groove keyed with the key.

5. The external rotor electric machine of claim 3, wherein the base end cap extends axially to form a cylinder surrounding part of the shaft seat, and the other axial end face of the core winding is axially abutted against the cylinder.

6. The external rotor electric machine of claim 2, further comprising a sealing cap, wherein the base end cap defines a stepped hole therethrough for receiving the bottom end of the shaft seat, and the sealing cap closes the stepped hole.

7. The external rotor electric machine of claim 1, further comprising a housing coupled to the base end cap and surrounding the rotor, the housing including an axial end face and a circumferential wall extending from the end face toward the base end cap, the second end of the shaft passing through the end face of the housing and being in clearance fit with the end face.

8. The external rotor electric machine of claim 7, wherein the rotor is sleeved on the rotating shaft through a flange, the flange and the second bearing are axially spaced apart, and a limiting sheet is sandwiched therebetween.

9. The outer rotor motor comprises a shell, a base end cover connected with the shell, an iron core winding fixedly arranged in the shell, and a rotating shaft rotatably arranged in the iron core winding, and is characterized by further comprising a bearing assembly for supporting the rotating shaft, wherein the bearing assembly is composed of a first bearing and a second bearing, the first bearing is embedded in the base end cover and sleeved with a first end of the rotating shaft, the second bearing is positioned in the iron core winding and sleeved with the middle of the rotating shaft, and a second end of the rotating shaft penetrates through the center of the shell and is in clearance fit with the shell.

10. The external rotor electric machine of claim 9, further comprising a shaft seat mounted on the shaft and located between the first bearing and the second bearing, the shaft seat being in clearance fit with the shaft, a bottom end of the shaft seat being embedded in the end cap of the base and forming a first bearing hole for mounting the first bearing, a top end of the core winding axially extending out of the shaft seat and forming a second bearing hole axially outside the shaft seat for mounting the second bearing.

Images