induction rotor

Abstract

The application belongs to the technical field of permanent magnet speed regulation devices, and particularly relates to an induction rotor, which comprises: a ring-shaped magnetic conduction inner core for guiding magnetic lines; an induction layer covering the magnetic conduction inner core for cutting the magnetic lines and generating induced current; and the induction layer comprises a first covering layer facing a permanent magnet rotor. The induction rotor is an inner rotor, and the first covering layer covers the outer peripheral surface of the magnetic conduction inner core. The induction rotor has a cooling structure, and the cooling structure comprises a water outlet formed on the outer peripheral surface of the induction rotor. The induction rotor of the scheme guides the magnetic lines through the magnetic conduction inner core, increases the magnetic flux density of the first covering layer on the outer peripheral surface of the magnetic conduction inner core, fully utilizes the magnetic field, and improves the upper limit of the torque transmitted by the induction rotor. The water outlet on the induction rotor can eliminate internal stress and avoid cracks on the first covering layer; and the cooling cavity on the induction rotor can cooperate with the water outlet to make the cooling liquid fully flow through the heating surface, so that the heat dissipation effect is ensured.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of permanent magnet speed regulation device, in particular to an induction rotor. BACKGROUND

[0002] The cylinder type permanent magnet speed regulator is a transmission device for transmitting torque through air gap. The existing cylinder type permanent magnet speed regulator mainly consists of an induction rotor and a permanent magnet rotor. The permanent magnet rotor and the induction rotor are connected to the motor and the load shaft respectively. There is an air gap between the induction rotor and the permanent magnet rotor. By adjusting the air gap distance or coupling area between the permanent magnet rotor and the induction rotor, the output power on the load shaft can be changed, so as to regulate the speed of the load.

[0003] In the existing large-scale cylinder type permanent magnet speed regulator, the induction rotor is usually made of pure copper or aluminum with good electrical conductivity. The conventional single metal induction rotor has poor magnetic conduction effect, and the magnetic lines on the permanent magnet are relatively loose, resulting in small magnetic flux density of the existing induction rotor, low effective utilization rate of the magnetic field, and low upper limit of the torque that can be transmitted by the induction rotor.

[0004] Therefore, it is urgent to design an induction rotor of a permanent magnet speed regulation device to improve the utilization rate of the magnetic field and increase the upper limit of the torque that can be transmitted by the induction rotor. SUMMARY

[0005] In view of the above problems, the present application provides an induction rotor which can improve the utilization rate of the magnetic field.

[0006] According to the induction rotor provided by the present embodiment, the induction rotor comprises:

[0007] A ring-shaped magnetic conduction inner core for guiding the magnetic lines;

[0008] An induction layer covering the magnetic conduction inner core for cutting the magnetic lines and generating induced current;

[0009] The induction layer comprises a first covering layer covering the peripheral surface of the magnetic conduction inner core and facing the permanent magnet rotor.

[0010] Preferably, the induction rotor is an inner rotor, and the first covering layer covers the outer peripheral surface of the magnetic conduction inner core.

[0011] Preferably, the induction rotor has a cooling structure, and the cooling structure comprises a water outlet formed on the outer peripheral surface of the induction rotor, and the water outlet is a slit distributed along the axial direction.

[0012] Preferably, the cooling structure further comprises a cooling cavity with an opening on one end surface of the induction rotor; and the side wall of the cooling cavity is in communication with the water outlet.

[0013] Preferably, the outer circumferential surface of the magnetic conductive inner core is uniformly distributed with open slots penetrating the magnetic conductive inner core in the axial direction; the open slots comprise inner cavities and tightened opening parts;

[0014] The water outlet is formed by the part of the first cover layer extending to the opening part;

[0015] The side wall of the cooling cavity is formed by the part of the first cover layer extending to the inner cavity.

[0016] Preferably, the induction layer further comprises a second cover layer and a third cover layer covering the two end surfaces of the magnetic conductive inner core respectively;

[0017] The opening of the cooling cavity is formed on the second cover layer;

[0018] The bottom surface of the cooling cavity is formed by the third cover layer.

[0019] Preferably, the bottom surface of the cooling cavity is provided with a through hole, and the water outlet extends to the through hole and communicates with the through hole.

[0020] Preferably, the cooling cavity is in a symmetrical structure with the gap as the axis.

[0021] Preferably, a flow guide boss is protruded on the second cover layer, and the flow guide boss is located at the edge of the second cover layer away from the first cover layer; the top of the flow guide boss is gradually flush with the second cover layer through a smooth transition curved surface.

[0022] Preferably, a blocking boss is protruded on the second cover layer; the blocking boss is located at the edge of the second cover layer close to the first cover layer.

[0023] The advantage of the scheme is that the magnetic conductive inner core with small magnetic resistance is arranged in the induction rotor, which guides the magnetic force lines in the magnetic field to pass through the magnetic conductive inner core to constrain the magnetic field. Especially on the surface of the magnetic conductive inner core opposite to the permanent magnet, the magnetic force lines concentrate to pass through the part of the induction layer covering the surface, thereby increasing the magnetic flux density of the induction layer, improving the utilization rate of the magnetic field, and increasing the upper limit of the torque transmitted by the induction rotor. When the volume of the induction rotor of the scheme is the same as that of the existing single-metal induction rotor, the induction rotor of the scheme can transmit greater torque. Moreover, the water outlet on the induction rotor can eliminate internal stress, avoid cracks on the first cover layer, and cooperate with the cooling cavity and the flow guide boss on the induction rotor to make the cooling liquid fully flow through the induction layer, which helps the induction rotor to dissipate heat. BRIEF DESCRIPTION OF DRAWINGS

[0024] Figure 1 Structure diagram of the first end surface of the induction rotor;

[0025] Figure 2 Structure diagram of the second end surface of the induction rotor;

[0026] Figure 3 Structure diagram of the cross section of the induction rotor;

[0027] Figure 4 Structure diagram of the cooling cavity;

[0028] Figure 5 Structure diagram of the magnetic conducting inner core;

[0029] Figure 6 Enlarged view of A;

[0030] Figure 7 Structure diagram of the cross section of the induction layer;

[0031] Figure 8 Structure diagram of the induction layer;

[0032] Figure 9 Structure diagram of the connection between the magnetic conducting inner core and the first covering layer.

[0033] In the figure, the magnetic conducting inner core 1, the open slot 11, the inner cavity 111, the open part 112, the embedded slot 13, the induction layer 2, the first covering layer 21, the cooling cavity 211, the water outlet 212, the rib 213, the second covering layer 22, the flow guiding boss 221, the fence boss 222, the third covering layer 23, the through hole 231. DETAILED DESCRIPTION

[0034] The following will be further explained in detail through specific embodiments:

[0035] The present embodiment relates to a cylindrical permanent magnet speed regulating device, which comprises an induction rotor and a permanent magnet rotor. The permanent magnet rotor is provided with circumferentially distributed permanent magnets, and the induction rotor is arranged in the circumference surrounded by the permanent magnets. As shown in the figure, the induction rotor is ring-shaped, comprising a magnetic conducting inner core 1 and an induction layer 2 cast on the surface of the magnetic conducting inner core 1. The magnetic conducting inner core 1 is made of alloy steel and used for restricting the magnetic field. The induction layer 2 is made of copper or aluminum or other metals or alloys with good electrical conductivity and used for cutting the magnetic force lines to generate induced current. The induction layer 2 in the present embodiment is preferably made of cast aluminum alloy, which is low in cost and easy to process. Figures 1 to 3

[0036] ​In the embodiment, the magnetically conductive inner core 1 of the induction rotor is located in the circumferential range surrounded by the permanent magnet, and the magnetically conductive inner core 1 can guide the magnetic lines to pass through the magnetically conductive inner core 1 from the side surface of the magnetically conductive inner core 1, so that the density of the magnetic lines is increased, the magnetic flux density of the induction layer 2 part on the outer circumferential surface of the magnetically conductive inner core 1 is increased, and the torque of the induction rotor is increased. Compared with the induction rotor made of single metal in the prior art, the induction rotor in the embodiment can improve the utilization rate of the magnetic field and increase the upper limit of the torque transmitted by the induction rotor. In addition, the thickness of the induction layer 2 in the embodiment is small, the material is less, and the production cost is low.

[0037] As shown in Figure 5 and Figure 6 , in the embodiment, the magnetically conductive inner core 1 is annular, and a plurality of uniformly distributed open grooves 11 penetrating the magnetically conductive inner core 1 in the axial direction are formed on the outer circumferential surface of the magnetically conductive inner core 1. The open grooves 11 can reduce the material of the magnetically conductive inner core 1 and reduce the weight of the induction rotor. The inner side wall of the magnetically conductive inner core 1 is protruded to form a mounting boss, and a mounting hole is formed on the mounting boss for connecting the shaft.

[0038] In the embodiment, the open groove 11 includes an inner cavity 111 and a tightened opening part 112, and the tightened opening part 112 is a part that the side wall of the open groove 11 protrudes at the opening position, so that the width of the open groove 11 at the opening part 112 is smaller than the width of the inner cavity 111. It can be understood that, since the open groove 11 is formed on the outer circumferential surface of the magnetically conductive inner core 1 and penetrates the magnetically conductive inner core 1 in the axial direction. Therefore, the open groove in the present scheme includes a bottom surface and two opposite side surfaces, and the width of the present scheme refers to the distance between the two opposite side surfaces.

[0039] As shown in Figure 3 , Figure 7 and Figure 8 , the induction layer 2 includes a first cover layer 21, a second cover layer 22 and a third cover layer 23. The first cover layer 21 constitutes the outer circumferential surface of the induction rotor, the second cover layer 22 constitutes the first end surface of the induction rotor, and the third cover layer 23 constitutes the second end surface of the induction rotor. In the embodiment, the permanent magnet speed regulation device further includes a cooling device, and the cooling device is arranged on one side of the induction rotor. The cooling device sprays cooling liquid on the first end surface of the induction rotor.

[0040] In the embodiment, the induction rotor has a cooling structure, which includes a water outlet 212 and a cooling cavity 211. The water outlet 212 is formed on the outer circumferential surface of the induction rotor and is a slit distributed in the axial direction. The opening of the cooling cavity 211 is located on one end surface of the induction rotor, and the side wall of the cooling cavity 211 is communicated with the water outlet 212.

[0041] In the embodiment, the first cover layer 21 comprises a first cover layer body covering the outer circumferential surface of the magnetically conductive inner core 1, and a recess extending from the first cover layer body into the open slot 11, which completely covers the surface of the open slot 11. The water outlet 212 of the cooling structure is formed by the part of the recess covering the opening 112. It can be understood that, since the open slot 11 penetrates the magnetically conductive inner core 1 from the axial direction, and the water outlet 212 is formed by the part of the recess covering the opening 112, the water outlet 212 extends into the magnetically conductive inner core 1 and penetrates the whole induction rotor from the axial direction. The slit-shaped water outlet 212 can adapt to the thermal expansion and contraction of the induction rotor, eliminate the internal stress of the induction rotor, and avoid cracks on the first cover layer 21. The water outlet 212 in the embodiment is distributed radially with the center of the induction rotor as the midpoint.

[0042] In the embodiment, since the induction rotor generates induction current by cutting the magnetic lines of force through the induction layer 2, the heat generated by the induction rotor is concentrated on the induction layer 2. The side wall of the cooling cavity 211 is formed by the part of the recess covering the inner cavity 111, and the heat concentrated on the induction layer 2 can be directly transferred into the cooling cavity 211 and dissipated through the cooling cavity 211, which is convenient for heat dissipation. Moreover, the cooling cavity 211 can increase the contact area of the cooling liquid with the induction layer 2, and improve the heat dissipation and cooling effect. In addition, the side wall of the cooling cavity 211 in the embodiment is in communication with the water outlet 212, and during the rotation of the induction rotor, the cooling liquid in the cooling cavity 211 can flow out of the induction rotor through the water outlet 212 under the action of centrifugal force, so that the cooling liquid can fully flow through the induction layer 2, and the heat dissipation effect is good. Moreover, the cooling liquid can flow into the air gap between the induction rotor and the permanent magnet rotor through the water outlet 212, and simultaneously cool the induction rotor and the permanent magnet rotor, and the utilization rate of the cooling liquid is high.

[0043] In the embodiment, the opening of the cooling cavity 211 is formed on the second cover layer 22, and the cooling cavity 211 is in communication with the outside through the opening. The third cover layer 23 completely covers the end surface of the magnetically conductive inner core 1 corresponding to the third cover layer 23. It should be noted that the opening of the cooling cavity 211 is the part of the cooling cavity 211 exposed by the second cover layer 22 and surrounded by the side wall and the water outlet 212. The third cover layer 23 covers the part of the cooling cavity 211 surrounded by the side wall and the water outlet 212 to form the bottom surface of the cooling cavity 211.

[0044] As shown in Figure 4 , the cooling liquid sprayed onto the first end surface can flow into the cooling cavity 211 from the opening, avoiding splashing of the cooling liquid away from the induction rotor, prolonging the residence time of the cooling liquid on the induction rotor, and helping to cool the induction rotor.

[0045] To further increase the flow area of the cooling liquid, the bottom surface of the cooling cavity 211 is provided with a through hole 231. The cooling liquid in the cooling cavity 211 can flow to the surface of the third cover layer 23 through the through hole 231, further improving the heat dissipation effect of the induction rotor.

[0046] In the present embodiment, the water outlet 212 extends to the through hole 231 through the second end surface and communicates with the through hole 231. The cooling cavity 211 is symmetrically structured with the water outlet 212 as the axis, ensuring the uniform quality of the induction rotor. The portion of the water outlet 212 extending to the through hole 231 can further improve the probability of the cooling liquid flowing to the third cover layer 23.

[0047] As shown in Figure 3 and Figure 7 In the present embodiment, the second cover layer 22 of the induction layer 2 is also provided with a flow guide structure for guiding the cooling liquid to flow into the cooling cavity 211. The flow guide structure is a flow guide boss 221 protruding from the edge of the second cover layer 22 away from the first cover layer 21. The surface of the flow guide boss 221 facing the first cover layer 21 is a smooth transition surface. In the direction facing the first cover layer 21, the height of the transition surface gradually decreases from the top of the flow guide boss 221 to the second cover layer 22, and the transition surface gradually aligns with the second cover layer 22 from the top of the flow guide boss 221.

[0048] The flow guide boss 221 in the present embodiment is integrally formed in a ring shape, ensuring that the flow guide boss 221 has enough transition surface to correspond to each cooling cavity 211. In some embodiments, the flow guide structure is a plurality of independent flow guide bosses 221 distributed at intervals. The flow guide bosses 221 are arranged in a circle on the second cover layer 22 and are arranged correspondingly with the cooling cavities 211.

[0049] In the present embodiment, the cooling liquid is sprayed onto the second cover layer 22, and under the guidance of the transition surface, the cooling liquid flows into the cooling cavity 211 through the opening, thereby reducing the probability of the cooling liquid splashing away from the induction rotor.

[0050] In the present embodiment, the second cover layer 22 is also provided with a surrounding boss 222 protruding therefrom. The surrounding boss 222 is located at the edge of the second cover layer 22 close to the first cover layer 21. The surrounding boss 222 can retain the cooling liquid and prevent the cooling liquid on the first cover layer 21 from directly leaving the induction rotor from the edge, ensuring that enough cooling liquid flows into the cooling cavity 211.

[0051] In the present embodiment, the flow guide boss 221, the surrounding boss 222, and the portion of the second cover layer 22 between the flow guide boss 221 and the surrounding boss 222 form a ring-shaped groove, which helps the cooling liquid to accumulate in the groove.

[0052] As shown in Figure 9As shown, in order to ensure that the first cover layer 21 of the induction layer is firmly connected with the outer circumferential surface of the magnetically conductive inner core 1, an embedding groove 13 is formed on the outer circumferential surface of the magnetically conductive inner core 1 along the axial direction, and the first cover layer 21 has a rib 213 which is adapted to the embedding groove 13, for increasing the contact area of the induction layer 2 with the magnetically conductive inner core 1 and improving the connection strength.

[0053] This application is not limited only to the description and embodiments described, and therefore additional advantages and modifications will readily occur to those skilled in the art, and therefore the application is not limited to the specific details, representative devices and illustrated examples shown and described herein, without departing from the spirit and scope of the general concepts defined by the claims and their equivalents.

Claims

1. An induction rotor, characterized in that, include: A ring-shaped magnetic core is used to guide magnetic lines of force; An induction layer, covering the magnetic core, is used to cut magnetic lines of force and generate induced current; The sensing layer includes a first covering layer covering the circumferential surface of the magnetic core and facing the permanent magnet rotor, and a second covering layer and a third covering layer covering the two end faces of the magnetic core respectively. The magnetic core has evenly distributed axially penetrating slots on its outer peripheral surface; each slot includes an inner cavity and a constricted opening. The induction rotor is an inner rotor, and the induction rotor has a cooling structure. The cooling structure includes a water outlet formed on the outer peripheral surface of the induction rotor. The water outlet is a slit distributed along the axial direction. The slit-shaped water outlet can adapt to the thermal expansion and contraction of the induction rotor, eliminate the internal stress of the induction rotor, and prevent cracks from appearing on the first covering layer. The cooling structure also includes a cooling cavity with an opening located on one end face of the induction rotor. The side wall of the cooling cavity is connected to the water outlet. The first covering layer covers the outer peripheral surface of the magnetically conductive inner core; The water outlet is formed by the portion of the first covering layer extending to the opening; the sidewall of the cooling chamber is formed by the portion of the first covering layer extending to the inner cavity; The opening of the cooling chamber is formed on the second covering layer; The bottom surface of the cooling chamber is formed by the third covering layer.

2. The induction rotor according to claim 1, characterized in that: The bottom surface of the cooling chamber has a through hole, and the water outlet extends to the through hole and communicates with the through hole.

3. The induction rotor according to claim 2, characterized in that: The cooling cavity has a symmetrical structure with the gap as the axis.

4. The induction rotor according to claim 3, characterized in that: A flow-guiding boss protrudes from the second cover layer and is located at the edge of the second cover layer away from the first cover layer; the top of the flow-guiding boss gradually becomes flush with the second cover layer through a smooth transition surface.

5. The induction rotor according to claim 4, characterized in that: The second covering layer protrudes to form a barrier boss; the barrier boss is located on the edge of the second covering layer near the first covering layer.

Images