WO2021073514A1

WO2021073514A1 - Electric air pump

Info

Publication number: WO2021073514A1
Application number: PCT/CN2020/120765
Authority: WO
Inventors: 任艳平; 曲涛; 张远春; 陶小鹤; 杜成顺; 陈安邦; 秦锐锋
Original assignee: 广东德昌电机有限公司
Priority date: 2019-10-16
Filing date: 2020-10-14
Publication date: 2021-04-22
Also published as: CN114514379A

Abstract

An electric air pump, comprising a pump casing (10), a motor (20) provided in the pump casing (10), an impeller (30) driven by the motor (20), and a controller (40) connected to the motor (20). The motor (20) is a brushless direct current motor, and comprises a rotating shaft. The impeller (30) is fixed on the rotating shaft. The pump casing (10) is sequentially provided with a first chamber (11), a second chamber (12), and a third chamber (13) along the axial direction of the motor (20). The first chamber (11) and the third chamber (13) are respectively located on both axial ends of the second chamber (12). The controller (40) is accommodated in the first chamber (11). The motor (20) is provided in the second chamber (12). The impeller is provided in the third chamber (13). The pump casing (10) is further provided with an air inlet portion (18) adjacent to the first chamber (11), an exhaust portion (19) adjacent to and in communication with the third chamber (13), and a flow passage (100) of which both ends are respectively in communication with the air inlet portion (18) and the third chamber (13). The electric air pump is driven by the brushless motor, and has fast response speed, long service life, low noise, and high efficiency.

Description

Electric air pump

Technical field

The invention relates to the field of electric technology, in particular to an electric air pump.

Background technique

Adding OPF (gasoline particulate filter) to the exhaust system of a car can effectively reduce the emission of harmful substances in the exhaust of the car. OPF is usually equipped with an electric air pump to transport secondary air into the exhaust pipe to promote harmful substances in the exhaust gas discharged by the engine, which is beneficial to the further oxidation of CO or HC. However, the existing electric air pump is driven by a brushed motor and has a series of shortcomings, such as slow response speed, short service life, high noise, and low efficiency.

technical problem

In view of this, the present invention aims to provide an electric air pump that can solve or at least alleviate the above-mentioned problems.

Technical solutions

An electric air pump includes a pump casing, a motor arranged in the pump casing, an impeller driven by the motor, and a controller connected to the motor. The motor is a DC brushless motor, the motor includes a rotating shaft, and the impeller is fixed. On the rotating shaft, the pump housing is sequentially provided with a first chamber, a second chamber, and a third chamber along the axial direction of the motor. The first chamber and the third chamber are respectively located in the axial direction of the second chamber At both ends, the controller is housed in the first chamber, the motor is disposed in the second chamber, the impeller is disposed in the third chamber, and the pump housing is also provided with a chamber adjacent to the first chamber The air inlet portion of, an exhaust portion adjacent to and communicated with the third chamber, and two ends respectively communicated with the air inlet portion and the flow passage of the third chamber.

An electric air pump, comprising: a motor with a rotating shaft; a casing extending in the axial direction of the rotating shaft and accommodating the motor; a first outer end cover and a second outer end cover respectively fixed on both ends of the casing ; An impeller connected to the rotating shaft and arranged near the second outer end cover; and a controller housed in the housing and close to the first pump cover; the electric air pump is provided with a cooling channel for working in the pump In the state, the cooling airflow is guided to cool and dissipate the electric air pump. The cooling channel includes an air inlet provided on the first outer end cover, a flow channel provided in the housing, and an exhaust provided on the second outer end cover. unit.

Beneficial effect

The electric air pump provided by the invention is driven by a brushless motor, and has fast response speed, long service life, low noise and high efficiency.

Description of the drawings

Fig. 1 is a three-dimensional assembly view of an electric air pump according to an embodiment of the present invention.

Fig. 2 is a cross-sectional view of the electric air pump shown in Fig. 1.

Fig. 3 is an exploded view of the electric air pump shown in Fig. 1.

Fig. 4 is another angle view of the housing of the electric air pump shown in Fig. 1.

Fig. 5 is a schematic cross-sectional view of the exhaust portion of the housing shown in Fig. 4.

Fig. 6 is another angled view of the second outer end cover of the electric air pump shown in Fig. 1.

Fig. 7 is a schematic diagram of the structure of the overheat protection element of the electric air pump shown in Fig. 1.

Fig. 8 is an assembly diagram of the motor stator of the electric air pump shown in Fig. 1.

Fig. 9 is an exploded view of the stator of the motor shown in Fig. 8.

Fig. 10 is a bottom view of the stator of the motor shown in Fig. 8.

Fig. 11 is a plan view of the iron core of the stator of the motor shown in Fig. 8.

Fig. 12 is a partial plan exploded view of the stator core shown in Fig. 11.

Fig. 13 is a schematic diagram of the structure of the connector of the electric air pump shown in Fig. 1.

Fig. 14 is an assembly diagram of the connector and the housing shown in Fig. 13.

Fig. 15 is an exploded view of Fig. 14.

FIG. 16 is a perspective schematic view of the motor rotor of the electric air pump shown in 1. FIG.

Fig. 17 is an exploded view of the rotor of the motor shown in Fig. 16.

Fig. 18 is a perspective schematic view of the iron core of the motor rotor shown in Fig. 16.

Fig. 19 is a plan view of the rotor core shown in Fig. 18.

Fig. 20 is a plan view of the core lamination of the rotor core shown in Fig. 18.

Fig. 21 is a perspective view of a magnetic induction element of the electric air pump shown in Fig. 1.

Fig. 22 is an exploded view of Fig. 21.

Fig. 23 is a schematic diagram of the shock-absorbing mounting member of the electric air pump shown in Fig. 1.

Fig. 24 is an exploded view of Fig. 23.

Fig. 25 is a perspective schematic view of the second embodiment of the electric air pump of the present invention.

Fig. 26 is a perspective schematic view of the third embodiment of the electric air pump of the present invention.

Fig. 27 is a perspective schematic view of a fourth embodiment of the electric air pump of the present invention.

Fig. 28 is a perspective schematic view of a fifth embodiment of the electric air pump of the present invention.

Embodiments of the present invention

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings and specific embodiments, so as to make the technical solutions and beneficial effects of the present invention clearer. It can be understood that the drawings are only provided for reference and illustration, and are not used to limit the present invention. The dimensions shown in the drawings are only for the convenience of clear description, and do not limit the proportional relationship.

Referring to FIGS. 1 to 3 at the same time, an electric air pump according to an embodiment of the present invention includes a pump housing 10, a motor 20 arranged in the pump housing 10, an impeller 30 driven by the motor 20, and a controller 40 connected to the motor 20. The motor 20 and the controller 40 jointly constitute the driving device of the electric air pump. A first chamber 11, a second chamber 12, and a third chamber 13 are formed in the pump housing 10, and the first chamber 11, the second chamber 12, and the third chamber 13 are along the line of the motor 20. Arranged in an axial sequence, the first chamber 11 and the third chamber 13 are respectively located at two axial ends of the second chamber 12. The controller 40 is installed in the first chamber 11, the motor 20 is installed in the second chamber 12, and the impeller 30 is installed in the third chamber 13.

The pump casing 10 includes a casing 14, an inner end cover 15, a first outer end cover 16, and a second outer end cover 17. The housing 14 is roughly in the shape of a hollow barrel. A boss 140 is formed on the inner wall surface of the housing 14 near its first end (the top end in FIGS. 1 and 2), and the inner end cover 15 is inserted into it. Inside the housing 14 and abutting on the boss 140, the inner end cover 15 is tightly fitted and fixed with the housing 14. In this embodiment, the inner end cover 15 and the housing 14 are connected by welding. The inner wall surface of the housing 14 is formed with a base 141 extending radially inward at a position close to its second end (the bottom end in FIGS. 1 and 2). The base 141 and the inner end cover 15 are The second chamber 12 is formed between.

A first opening 150 and a second opening 151 are formed in the center of the inner end cover 15 so that the rotor 22 of the motor 20 can be pivotally connected to the inner end cover 15. The first opening 150 and the second opening 151 are arranged sequentially along the axial direction, and the inner wall surface of the inner end cover 15 forms a flange 152 between the first opening 150 and the second opening 151. A cap 153 is connected to the inner end cap 15 by screws and other fixing parts and closes the first opening 150 of the inner end cap 15. Preferably, a sealing ring 50 is provided between the cap 153 and the inner end cap 15 , To ensure the tightness of the connection between the two; an annular accommodation groove 154 is formed on the outer wall of the inner end cover 15, and a sealing ring 51 is provided in the accommodation groove 154 to ensure that the inner end cover 15 and the housing 14 The airtightness between the inner wall surfaces of the battery prevents dust, water vapor, etc. from entering the second chamber 12 and affecting the electrical safety of the motor 20.

The first outer end cover 16 is disposed at the top of the housing 14 and forms the closed first cavity 11 between the first outer end cover 16 and the inner end cover 15. In this embodiment, both the first outer end cover 16 and the housing 14 are formed with fixing holes, and fixing members such as screws pass through the corresponding fixing holes to fix the first outer end cover 16 to the top of the housing 14. Preferably, the first outer end cover 16 protrudes downward to form a ring rim 160, and the top end of the housing 14 is formed with an annular slot 142, and the ring rim 160 is inserted into the slot 142 during assembly. Therefore, the interface between the first outer end cover 16 and the housing 14 is in a tortuous shape, which can effectively prevent external dust, water vapor, etc. from entering the first chamber 11 and affecting the electrical safety of the controller 40. Preferably, the first outer end cover 16 is made of a high thermal conductivity material such as cast aluminum, so it also functions as a heat sink. In this embodiment, the first outer end cover 16 has features such as several columnar protrusions to increase the heat dissipation area and enhance the heat dissipation effect. The second outer end cover 17 is disposed at the bottom end of the housing 14 and closes the bottom end of the housing 14. The third cavity 13 is formed between the second outer end cover 17 and the base 141. In this embodiment, both the second outer end cover 17 and the casing 14 are formed with fixing holes, and fixing members such as screws pass through the corresponding fixing holes to fix the second outer end cover 17 to the bottom end of the casing 14. Preferably, a sealing ring 52 is provided between the second outer end cover 17 and the housing 14 to ensure the tightness of the connection between the two, and avoid leakage of air flow due to inadequate sealing.

An air inlet 18 and an air outlet 19 are formed on the pump housing 10, and a flow passage 100 is formed in the pump housing 10 to communicate the air inlet 18 and the third chamber 13. In this embodiment, the intake portion 18 is formed on the top of the pump casing 10 and the exhaust portion 19 is formed on the bottom of the pump casing 10, that is, the intake portion 18 and the exhaust portion 19 are respectively close to each other. The opposite ends of the motor 20 are described. Specifically, the air inlet portion 18 is formed on the first outer end cover 16. The air intake portion 18 is a hollow cylindrical portion extending axially parallel to the motor 20 and not coaxial with the motor 20. The exhaust portion 19 is formed on the side wall of the housing 14 close to the second outer end cover 17. The exhaust portion 19 is a hollow cylinder extending along the tangential direction of the outer circumference of the casing 14 and perpendicular to the intake portion 18. The exhaust portion 19 communicates the third chamber 13 with the outside. The flow channel 100 extends along the axis parallel to the motor 20 and is not coaxial with the motor 20. Preferably, the flow channel 100 is coaxial with the air inlet 18. In this embodiment, the cross section of the flow channel 100 is substantially D-shaped. During operation, the air flow is introduced into the pump housing 10 from the air intake portion 18, flows along the flow channel 100, and then is discharged from the pump housing 10 by the exhaust portion 19. In this embodiment, the air intake The part 18 and the exhaust part 19 are respectively located at the two ends of the pump casing 10. The airflow axially passes through the pump casing 10 and directly contacts the walls of the first chamber 11 and the second chamber 13, which can effectively affect the motor 20 and the controller 40. To dissipate heat, that is, the intake portion 18, the flow passage 100, and the exhaust portion 19 jointly constitute a cooling passage. Preferably, the housing 14, the first outer end cover 16, and the second outer end cover 17 are made of high thermal conductivity materials, and the cooling channel is designed so that in operation, most of the controller (more than 50 %) heat load can be dissipated into the cooling air flow through the pump housing. The high thermal conductivity material can be a metallic material, such as cast aluminum, or a non-metallic material, such as a synthetic material (plastic) added with high thermal conductivity non-metallic material particles (such as carbon black particles) or metal particles (such as aluminum particles) . Of course, the housing 14, the first outer end cover 16, and the second outer end cover 17 may be made of different materials. For example, the housing 14 may be made of cast aluminum, and the first outer end cover 16 is made of a synthetic material whose thermal conductivity is lower than that of the housing 14.

It should be pointed out that, in order to ensure the normal operation of the motor 20 and the controller 40, the flow channel 100 is not connected to the first and second chambers 11, 13, that is, the generated air flow does not flow into the first and second chambers. 11 and 13 are in direct contact with the motor 20 and the controller 40.

As shown in FIGS. 4-5, the base 141 of the housing 14 is recessed toward a side of the second outer end cover 17 to form a first channel 101. The first channel 101 is substantially C-shaped and extends around the central axis of the housing 14. In this embodiment, the radially outer peripheral edge of the first channel 101 is located at the connection between the inner side wall surface of the housing 14 and the base 141, and one end of the first channel 101 is connected to the exhaust port 19 and the other end through an outlet section 102. It extends to communicate with the flow channel 100, and the end of the first channel 101 connected to the flow channel 100 is the air flow inlet of the third chamber 13. In this embodiment, the outlet section extends in a straight line, but the cross-sectional area of the outlet section 102 is smaller than the cross-sectional area of the first channel 101, thereby accelerating the airflow.

As shown in FIG. 6, the second outer end cover 17 is recessed toward the base 141 to form a second channel 106, and the second channel 106 corresponds to the first channel 101 in position. Similarly, the second channel 106 extends substantially in a C shape and extends around the center of the second outer end cap 17; the cross section of the second channel 106 is substantially D-shaped. One end of the second channel 106 communicates with the airflow inlet of the third chamber 13, and the other end extends to an inclined surface 107, and the inclined surface 107 is opposite to the position of the exhaust portion 19.

The exhaust portion 19 is non-circular in cross section of the inner cavity perpendicular to the airflow direction, and is enclosed by a first inner edge 191, a second inner edge 192, and a third inner edge 193 that are connected end to end in the circumferential direction. The first inner edge 191 and the second inner edge 192 are substantially V-shaped, and the V-shape opens toward the radially outer side of the housing 14. The first inner edge 191 and the rotation axis OO of the impeller 30 form a first included angle α , and the first included angle α ranges from 0° to 90°. The second inner edge 192 and the rotation axis OO of the impeller 30 form a second included angle β , and the second included angle β ranges from 0° to 90°. Preferably, the first angle α is 45°, the second angle β is 45°, and the angle between the first inner edge 191 and the second inner edge 192 is 90°. The third inner edge 193 is an arc segment connecting the first inner edge 191 and the second inner edge 192, and the center of the arc segment 193 deviates from the intersection of the first inner edge 191 and the second inner edge 192.

Further, the inner wall surface of the housing 14 is protrudingly provided with a convex portion 103, the convex portion 103 is located between the two ends of the first channel 101, and a first inclined portion 104 is formed on both sides of the convex portion 103 in the circumferential direction. And the second inclined portion 105, wherein the first inclined portion 104 is adjacent to the flow channel 100 and located upstream of the airflow inlet of the third chamber 13, and the second inclined portion 105 is adjacent to the exhaust portion 19 and located downstream of the exhaust portion 19. The first inclined portion 104 and the second inclined portion 105 are arranged obliquely with respect to the rotation axis OO of the impeller 30 and the inclined directions are opposite. The first inclined portion 104 and the second inclined portion 105 face the end of the second outer end cover 17 The ends close to each other and facing the base 141 are far away from each other, thereby reducing the pressure pulsation caused by the air flow, thereby improving aerodynamic audio noise.

The impeller 30 is rotatably disposed in the third chamber 13, and the diameter of the impeller 30 is smaller than the inner diameter of the housing 14, so that a gap is formed between the impeller 30 and the housing 14, and the gap is connected to the first passage 101 and the first passage. 101 is connected. Under the action of the impeller 30, the external airflow enters the pump casing 10 from the air inlet 18, flows through the first chamber 11 and the second chamber 12 along the flow path 100, and then enters the third chamber 13, and finally flows from the exhaust part. 19 flows out of the pump housing 10. The exhaust portion 19 of the electric air pump of the present invention forms a non-circular cavity cross-section, and a first inclined portion 104 is formed upstream of the airflow inlet and a second inclined portion 105 is formed downstream of the exhaust portion 19, which reduces the airflow caused The pressure pulsation, which effectively reduces the noise. In addition, during the flow of the airflow in the pump housing 10, it flows through the second chamber 12 and takes away the heat generated by the motor 20 in the second chamber 12, which has a heat dissipation effect on the motor 20 and ensures that the controller The working temperature of 40 and the motor 20 are within the proper range to ensure electrical safety and prolong the service life.

As shown in FIG. 3, the motor 20 is a DC brushless motor, and includes a stator 21 and a rotor 22 that rotates relative to the stator 21. The motor 20 is an inner rotor motor, and the stator 21 is arranged around the rotor 22. The impeller 30 is fixedly connected to the rotor 22 and rotates synchronously with the rotor 22. The controller 40 is electrically connected to the motor stator 21 to control the rotation of the motor 20.

As shown in FIGS. 2, 3 and 7, the controller 40 is fixedly connected to the housing 14 by screws or the like, and includes a circuit board 49 and a number of electronic devices arranged on the circuit board 49. The inner end cover 15 is a cast aluminum piece with high thermal conductivity, and acts as a heat sink to dissipate the circuit board 49. Preferably, the controller 40 further includes an overheating protection element 41 connected to the circuit board 49. When the temperature is too high, the overheating protection element 41 will fuse to protect the motor 20 from power failure. Specifically, the overheat protection element 41 includes a first terminal 42, a second terminal 43, and an elastic piece 44 integrally extending from the first terminal 42. The first terminal 42 and the second terminal 43 are plugged into the circuit board 49 and connected to the corresponding positive and negative contacts on the circuit board 49, that is, the first terminal 42 and the second terminal 43 are serially connected to the circuit board 49 In the power supply circuit. The extension direction of the elastic piece 44 under unstressed conditions deviates from the connecting line of the first terminal 42 and the second terminal 43 by a certain angle, so that the end of the elastic piece 44 deviates from the second terminal 43 by a small amount under unstressed conditions. distance. During assembly, the end of the elastic piece 44 is electrically connected to the second terminal 43 by soldering and mechanically fixed, and the elastic piece 44 is elastically deformed at this time.

Preferably, the first terminal 42 and the second terminal 43 are assembled into one body by a frame 45. The frame 45 is in the shape of "ㄈ" and includes a first cross bar 46 and a second cross bar arranged in parallel up and down. 47. And a connecting rod 48 connecting the first crossbar 46 and the second crossbar 47, the tops of the first terminal 42 and the second terminal 43 are respectively inserted and fixed in the first crossbar 46, the first terminals 42, The bottom of the second terminal 43 is fixed to the second cross bar 47, passes through the second cross bar 47, and is connected to the circuit board 49. In this way, the relative positions of the first terminal 42 and the second terminal 43 and the alignment connection with the circuit board 49 are ensured, and the connection between the first terminal 42 and the second terminal 43 and the circuit board 49 is stable. In this embodiment, the first terminal 42 is disposed close to the connecting rod 48, and the second terminal 43 is disposed close to the opening side of the frame 45, which facilitates the fixing of the elastic piece 44 and the second terminal 43 by soldering. The elastic piece 44 is located between the first cross bar 46 and the second cross bar 47. When the elastic piece 44 is welded to the second terminal 43, it is approximately parallel to the first cross bar 46 and the second cross bar 47. Otherwise, the elastic piece 44 is in the It forms an angle with the first crossbar 46 and the second crossbar 47 when it is not under force.

Referring to FIGS. 8-12 at the same time, the motor stator 21 includes a stator core 210 and a coil 211 wound on the stator core 210. The stator core 210 is formed by splicing a plurality of stator core segments 212. In this embodiment, there are six core segments 212, and each core segment 212 serves as a magnetic pole of the stator 21. Each core segment 212 is formed by stacking a plurality of core laminations, including an inner arc 213, an outer arc 214, and a tooth body 215 connecting the inner arc 213 and the outer arc 214. The inner arcs 213 of the respective iron core segments 212 jointly form the inner ring of the stator iron core 210, and the outer arcs 214 jointly form the outer ring of the stator iron core 210. The coil 211 is wound on the tooth body 215. Preferably, an insulating frame 216 is installed at the axial end of each core segment 212, and the insulating frame 216 isolates the coil 211 to avoid short circuit. Since the stator iron core 210 is composed of multiple splicing sections, each iron core section 212 can be individually wound in advance, so that the winding is not affected by the adjacent iron core sections 212, ensuring the winding slot full rate and improving the motor 20 efficiency.

The two circumferential ends of the outer arc portion 214 of each iron core segment 212 of the stator iron core 210 are respectively formed with a bump 218 and a groove 219. The protrusion 218 and the recess 219 are similar in shape and size, and both are substantially semicircular in this embodiment. When assembling, the protrusion 218 of each core segment 212 is inserted into the groove 219 of an adjacent core segment 212, and correspondingly, the groove 219 is inserted into the protrusion 218 of another adjacent core segment 212. Then, through the engagement of the protrusion 218 and the groove 219, each iron core segment 212 is connected into a complete circle structure. In addition, the circumferential ends of the outer peripheral surface of the outer arc portion 214 of each iron core segment 212 are respectively recessed to form a recess 2140, and a tiny protrusion 2141 is formed at the outer circumference of the recess 2140, and each iron core After the segment 212 is connected to the groove 219 by the bump 218, the two protrusions 2141 at the ends of the two adjacent iron core segments 212 are close to each other and connected by welding to ensure the stability of the connection of each iron core segment 212 This prevents the groove 219 and the bump 218 from being unstable or even disconnected due to wear and other reasons. Preferably, the protrusion 2141 does not exceed the outer circumferential surface of the core segment 212 in the radial direction, and does not affect the overall shape of the stator 21 after welding.

The stator coil 211 is provided with a connecting seat 217, the connecting seat 27 is formed with a pin 2170, the coil 211 is electrically connected to the pin 2170 through the connecting seat 217, and the pin 2170 is connected to the control via the connector 23器40连接。 Device 40 is connected.

As shown in FIGS. 13-15, the connector 23 includes a terminal sleeve 230 and a plurality of terminals 231 fixed in the terminal sleeve 230. In this embodiment, the terminal sleeve 230 is connected to the outer side wall of the housing 14 corresponding to the first cavity 11 by a fixing member such as screws, and an opening 149 is formed on the outer side wall of the housing 14 and surrounds the opening. The hole 149 is formed with a ring groove 148. The terminal sleeve 230 includes an abutting end connected with the housing and a plug-in end for inserting a corresponding external connector. A ring-shaped rib 232 is formed on the abutting end of the terminal sleeve, and the rib 232 is inserted into the ring groove 148. Preferably, there is a potting glue, such as Dowsil 9176, etc., in the ring groove 148 to seally connect the terminal sleeve 230 and the housing 14. Because the rib 232 is inserted into the ring groove 148, the contact area between the housing 14 and the terminal sleeve 230 is increased, the bonding between the two is firmer, and the sealing area is effectively increased, ensuring the tightness and stability of the connection, and avoiding external connections. The entry of water vapor, dust, etc. into the first chamber 11 affects the electrical safety of the controller 40.

The abutting end of the terminal sleeve 230 forms another annular rib 233 in the enclosed area of the rib 232, and the terminal 231 is disposed in the enclosed area of the rib 233 and faces the opening 149 on the side wall. . Preferably, the terminal 231 is fixed to the terminal sleeve 230 by insert molding, and then a potting glue is filled in the enclosed area of the protruding rib 233 to ensure the stability of the connection of the terminal 231 and the connection between the terminal 231 and the terminal sleeve 230 Seal between. One end of the terminal 231 facing the housing 14 is connected to the controller 40, and the other end is used to connect an external power source and a control signal source. In this embodiment, the terminal 231 is connected to the controller 40 through the overheat protection element 41, that is, two of the terminals 231 connected to an external power source are respectively connected to the first terminal 42 and the second terminal 43 of the overheat protection element 41. In a normal state, the elastic piece 44 is welded to the second terminal 43 so that the motor 20 is connected to the external power source. The controller 40 periodically changes the current of the stator coil 211 as needed, thereby generating a changing magnetic field that interacts with the magnetic field of the rotor 22 , The rotor 22 is pushed to continuously rotate.

When the electric air pump of the present invention produces an abnormality such as internal overheating, the temperature will usually be higher than the melting point of the solder joint between the elastic piece 44 and the second terminal 43 (such as 220°C). At this time, the elastic piece 44 and the second terminal 43 are fused, and the elastic piece 44 is in its place. Under the action of its own elastic restoring force, the deformation is restored and the second terminal 43 is deviated, so that the motor 20 is disconnected from the external power supply. In this way, when the internal outlet of the electric air pump of the present invention is overheated, the power can be cut off in time and automatically to enhance safety .

As shown in Figures 16-17, the rotor 22 is rotatably arranged in the inner ring of the stator 21, including a rotating shaft 220, a rotor core 221 fixedly sleeved on the rotating shaft 220, and a rotor core 221 inserted in the rotor core 221 Permanent magnets 222.

Please also refer to FIG. 2, the rotating shaft 220 is a longitudinal rod body, and the bottom end of the rotating shaft 220 passes through the base 141 and extends into the third chamber 13. The impeller 30 is fixedly sleeved on the bottom end of the rotating shaft 220 to rotate synchronously with the rotating shaft 220. A bearing hole is formed on the base 141, a first bearing 24 is arranged in the bearing hole, and the bottom end of the rotating shaft 220 is inserted into the first bearing 24, preferably the first bearing 24 is a ball bearing. The top end of the rotating shaft 220 passes through the first opening 150 and the second opening 151 of the inner end cover 15. The second opening 151 is provided with a second bearing 25, and the second bearing 25 is preferably It is a ball bearing. The first bearing 24 and the second bearing 25 are separately provided at both ends of the rotating shaft 220 to support the rotation of the rotor 22, so that the rotation is more stable and smooth, and the noise is low.

Please refer to FIGS. 2, 22 and 23 at the same time. The first opening 150 is provided with a magnetic induction element 26, and the magnetic induction element 26 is fixedly sleeved on the top of the rotating shaft 220 and rotates synchronously with the rotor 22. Since the motor 20 is a brushless motor, the magnetic induction element 26 is used to detect the rotation position of the motor rotor, so that the controller 40 can quickly start the motor according to the rotor position. The magnetic induction element 26 includes a magnetic ring 260, a protective cover 261 sleeved on the magnetic ring 260, and a connecting member 262. The magnetic ring 260 is made of polymer material dispersed and mixed with magnetic powder through injection molding. The magnetic ring 260 has a circular ring structure, and a connecting hole 263 is formed in the center of the magnetic ring 260. The connecting member 262 is inserted into the connecting hole 263 and is fixedly connected to the magnetic ring 260. In this embodiment, the connecting member 26 is fixed to the magnetic ring 260 through an insert molding process. A waist-shaped mounting hole 264 is formed in the center of the connecting member 262. The top end of the rotating shaft 220 is cut, and the cross section is waist-shaped, which matches the mounting hole 264 of the connecting member 262 of the magnetic ring 260. When assembling, the top end of the rotating shaft 220 is inserted into the mounting hole 264 of the connecting member 262, and the two form a limit in the circumferential direction and cannot rotate relative to each other. The protective cover 261 is made of high-strength, high-toughness and non-magnetic materials, such as stainless steel, copper, nylon, and the like. The shape of the protective cover 261 matches the magnetic ring 260 and its strength is greater than that of the magnetic ring 260, so as to protect the magnetic ring 260 from damage during high-speed rotation. In this embodiment, the protective cover 261 and the magnetic ring 260 are fixed by glue. In other embodiments, the magnetic ring 260 and the protective cover 261 can also be fixed by other fixing methods, such as tight fitting.

In this embodiment, as shown in FIGS. 18-20, the rotor core 221 is composed of two sub-cores 221a and 221b. The two sub-cores 221a and 221b have the same structure, and each sub-core 221a or 221b is composed of A number of laminated cores are stacked. The two sub-iron cores 221a and 221b are sequentially sleeved on the rotating shaft 220, and the two rotor cores 221 are arranged coaxially in the axial direction but relatively deflected in the circumferential direction. In this embodiment, the two sub-iron cores 221a and 221b are relatively deflected by approximately 11.25° in the circumferential direction, which effectively reduces the cogging torque and torque fluctuations, and reduces the noise of the electric air pump of the present invention.

Along the circumferential direction of the rotor 22, each sub-core 221a or 221b includes a plurality of inner concave portions 223 and outer convex portions 224 arranged at intervals. In this embodiment, there are four inner concave portions 223 and four outer convex portions 224, so Each of the convex portions 224 serves as a magnetic pole of the rotor 22. Since the number of the outer protrusions 224 of the rotor core 221 is different from the number of the stator core segments 212, the formation of dead spots can be avoided and the rotor 22 can be started smoothly. The outer convex portion 224 has an outer convex arc shape, the inner concave portion 223 has an inner concave arc shape, and the length of the outer convex portion 224 in the circumferential direction is much greater than the length of the inner concave portion 223. The center of the outer convex portion 224 deviates from the center of the rotor core 221, so that the distance between the outer edge of the outer convex portion 224 and the rotor core 221 changes. In this way, after the rotor 22 is assembled with the stator 21, the distance between the inner ring of the stator 21 and the outer edge of the rotor core 221 is changed, and a non-uniform air gap is formed between the stator 21 and the rotor 22, thereby improving the back-EMF waveform Making it close to the sine wave further reduces the vibration and noise of the electric air pump of the present invention.

Each sub-core 221a or 221b is formed with a through hole 225 for installing a permanent magnet 222. In this embodiment, correspondingly, the number of the magnets is four. Each outer protrusion 224 of the sub-iron core 221a or 221b forms a perforation 225, two adjacent perforations 225 are perpendicular to each other, and the four perforations 225 are arranged in a square shape. The two ends of each perforation 225 are close to the position of the inner recess 223 of the rotor core 221 but do not penetrate the inner recess 223. The rotor core 221 has the smallest thickness dimension W at the end position corresponding to the perforation 225, preferably W is 0.5mm to reduce magnetic flux leakage and improve the efficiency of the motor 20. The four magnets are respectively inserted into the four perforations 225 of the rotor core 221. In this embodiment, a partition 226 is provided at the outer end of each rotor core 221, and the partition 226 faces the magnets in the axial direction. A limit is formed to prevent the magnet from falling during the high-speed rotation and vibration of the rotor 22. In this embodiment, the partitions 226 are fixedly sleeved on the rotating shaft 220. By adjusting the structure and weight of the two partitions 226, the balance of the rotor 22 can be ensured and noise can be reduced.

As shown in Figure 1, Figure 23 and Figure 24, the pump housing 10 of the electric air pump of the present invention is also connected with a bracket 60 for connecting the electric air pump of the present invention to other mechanisms of the vehicle. A plurality of shock-absorbing mounting members 70 are arranged between the bracket 60 and the pump casing 10. The shock-absorbing mounting member 70 includes an elastic body 71 and a first screw 72 and a second screw 73 respectively connected to two ends of the elastic body 71. The elastic body 71 may be made of rubber or other materials. Two ends of the elastic body 71 respectively form a ring sleeve 74, and the ring sleeve 74 is tightly sleeved on the heads of the first screw 72 and the second screw 73. The screw of the first screw 72 is screwed and fixed with the housing 14, and the screw of the second screw 73 is screwed and fixed with the bracket 60. The vibration of the electric air pump is buffered by the elastic member and will not continue to be transmitted to the bracket 60. As well as other mechanisms connected with the bracket 60, the shock-absorbing mounting member 70 blocks the transmission of the vibration of the electric air pump to the outside, and reduces the impact on other components as much as possible.

According to the specific application environment of the electric air pump of the present invention, as shown in FIGS. 25-27, the bracket 60 can have different structures. The structure of the bracket 60 shown in FIG. 25 is the same as that of FIG. 1, and the bracket 60 is sleeved on the housing 14. It is connected to the outer wall surface of the housing 14 through a shock-absorbing mounting member 70; in the embodiment shown in FIG. 26, a bracket 60 surrounds the housing 14 and forms a heat insulation baffle on one side of the housing 14 to reduce engine production. The influence of the heat on the normal operation of the electric air pump. A shock-absorbing mounting member 70 is provided between the bracket 60 and the housing 14; in the embodiment shown in FIG. 27, the bracket 60 is half sleeved on the housing 14, and a shock-absorbing mounting member 70 is provided between the bracket 60 and the housing 14. Similarly, according to the specific application environment of the electric air pump of the present invention, the connector 23 of the electric air pump of the present invention can be installed in different ways. In the embodiments shown in Figs. 1 and 28, the outer end of the connector 23 faces downward; Fig. 25 In the embodiment shown in FIG. 26, the outer end of the connector 23 is arranged upward, while in the embodiment shown in FIG. 27, the outer end of the connector 23 is arranged obliquely downward. Through different bracket structures, it can be adapted to different installation spaces. At the same time, the connectors are installed at different angles according to the installation environment to facilitate the connection with other electronic devices.

The above are only the preferred specific embodiments of the present invention. The protection scope of the present invention is not limited to the above-listed examples. Any person skilled in the art can obviously obtain the technology within the technical scope disclosed in the present invention. Simple changes or equivalent replacements of the solutions fall within the protection scope of the present invention.

Claims

An electric air pump includes a pump casing, a motor arranged in the pump casing, an impeller driven by the motor, and a controller connected to the motor. The motor is a DC brushless motor, the motor includes a rotating shaft, and the impeller is fixed. On the rotating shaft, the pump housing is sequentially provided with a first chamber, a second chamber, and a third chamber along the axial direction of the motor. The first chamber and the third chamber are respectively located in the axial direction of the second chamber At both ends, the controller is housed in the first chamber, the motor is disposed in the second chamber, the impeller is disposed in the third chamber, and the pump housing is also provided with a chamber adjacent to the first chamber The air inlet portion of, an exhaust portion adjacent to and communicated with the third chamber, and two ends respectively communicated with the air inlet portion and the flow passage of the third chamber.
The electric air pump according to claim 1, wherein the pump housing includes a cylindrical housing with two ends open, and a first outer end cover and a second outer end cover respectively covering both ends of the housing, so The air inlet part is opened on the first outer end cover, and the air outlet part is formed on the side wall of the housing close to the second outer end cover.
3. The electric air pump according to claim 2, wherein the air intake part is a hollow cylindrical part extending parallel to the axis of the motor but deviating from the axis of rotation of the motor.
The electric air pump according to claim 2, wherein the exhaust part is a hollow cylinder extending tangentially along the outer circumference of the casing.
The electric air pump according to claim 3, wherein the flow channel extends parallel to the axial direction of the motor and is not on the same axis as the motor.
5. The electric air pump according to claim 5, wherein the flow passage is coaxial with the air inlet.
The electric air pump according to claim 5 or 6, wherein the cross section of the flow channel is substantially D-shaped.
The electric air pump according to claim 2, wherein the pump housing further includes an inner end cover fixed to the housing, and the inner wall surface of the housing is formed with a base near the second outer end cover. Seat, the first chamber is formed between the inner end cover and the first outer end cover, the second chamber is formed between the base and the inner end cover, and the second end The third cavity is formed between the cover and the base.
8. The electric air pump according to claim 8, wherein the inner end cover and the housing are connected by welding.
The electric air pump according to claim 8, wherein the inner end cover is provided with an opening for the motor to rotate, and the electric air pump further includes a cap, the cap being fixed on the The inner end cover faces one side of the first chamber and closes the opening of the inner end cover.
The electric air pump according to claim 10, wherein a sealing ring is provided between the cap and the inner end cover.
The electric air pump according to claim 2, wherein the first outer end cover is made of cast aluminum.
The electric air pump according to claim 2, wherein the end of the side wall of the housing close to the first outer end cover is formed with an annular slot, and the outer edge of the first outer end cover is convex A ring is provided, and the ring is inserted into the slot.
The electric air pump according to claim 1, wherein the flow channel is not connected with the first and second chambers.
An electric air pump, including:

　　Motor with rotating shaft;

　　 extends in the axial direction of the rotating shaft and houses the housing of the motor;

　　 a first outer end cover and a second outer end cover respectively fixed on both ends of the shell;

　　 an impeller connected to the rotating shaft and arranged near the second outer end cover; and

　　 a controller housed in the casing and close to the first pump cover;

The electric air pump is provided with a cooling channel for guiding the cooling air flow to cool and dissipate the electric air pump when the pump is working, and the cooling channel includes an air intake portion arranged on the first outer end cover and arranged in the housing The flow channel and the exhaust part arranged on the second outer end cover.
The electric air pump according to claim 15, wherein the cooling air flows through the cooling channel to first cool the controller, and then cool the motor.
The electric air pump according to claim 15, characterized in that: the housing, the first outer end cover and the second outer end cover are made of high thermal conductivity materials, and the cooling channel is designed so that the More than 50% of the heat load of the pump can be dissipated into the cooling air flow through the pump housing.
The electric air pump according to claim 17, wherein the first outer end cover is made of a synthetic material with a lower thermal conductivity than the housing.
The electric air pump according to claim 18, wherein the housing can be made of metal.
The electric air pump according to claim 19, wherein the housing can be made of aluminum.
15. The electric air pump according to claim 15, wherein the housing is formed to contain the exhaust part to guide the air flow to be eliminated along the tangential direction of the impeller.
The electric air pump according to claim 15, wherein a controller accommodating chamber for accommodating the controller is formed in the housing, and the controller accommodating chamber is not connected to the cooling channel and is sealed against the cooling air flow .
15. The electric air pump according to claim 15, wherein an impeller accommodation chamber for accommodating the impeller is formed in the housing, and the exhaust portion guides the airflow to exit the impeller accommodation chamber along a tangential direction of the impeller.