Permanent magnet motor for refrigerant compressor

Abstract

The application discloses a kind of permanent magnet motor for refrigerant compressor, including permanent magnet rotor, permanent magnet rotor is by rotor inner core, permanent magnet, rotor iron core block and end cap composition, rotor inner core outer circumferential side surface interval is equipped with arc groove, arc groove is superior camber, adjacent arc groove forms convex rib, rotor iron core block is by fan body part and fan handle part integral composition, fan handle part outer edge is convex arc surface, convex arc surface and arc groove movable cooperation, rotor iron core block is by multiple fan-shaped iron core piece riveting together, fan-shaped iron core piece its fan handle piece outer edge is convex arc edge, convex arc edge is superior camber;Each end cap outer edge inner wall extends out circumferential interval boss axially, permanent magnet is arranged in the containing groove between adjacent rotor iron core block one by one, each permanent magnet is installed between convex rib and boss;Permanent magnet is 10 block strip-shaped ferrite magnetic steel, stator slot is 12.The permanent magnet motor after using the above scheme, harmonic loss is small, leakage is small and cost is low, permanent magnet installation degree of freedom is good, fixed reliably.

Description

[0001] The application relates to a permanent magnet motor for a refrigerant compressor and belongs to the technical field of permanent magnet motors for refrigerant compressors.

[0002] The common rotor core is of an integrated design, which is composed of a hollow column part for mounting a rotor shaft and a plurality of fan-shaped sub-cores extending radially from the outer side wall of the hollow column part and distributed in a circumferential interval, wherein the plurality of fan-shaped sub-cores are integrally connected to the outer side wall of the hollow column part, and an installation groove for mounting a permanent magnet is formed between adjacent fan-shaped sub-cores; the integrated rotor core has the disadvantage of easy magnetic leakage; another common rotor core is of an inlaid design, the outer side wall of the hollow column part is provided with wedge-shaped blocks in a circumferential interval, and a wedge-shaped groove is formed between two adjacent wedge-shaped blocks; the inner end of the split core is provided with a split core wedge-shaped block, and the split core wedge-shaped blocks are fixed in the wedge-shaped grooves of the hollow column part one by one, so as to form an inlaid rotor core structure; and an installation groove for mounting a permanent magnet is formed between adjacent split cores.

[0003] The above two kinds of rotor cores have the same technical deficiencies as follows:

[0004] The fan-shaped sub-cores or the split cores are fixed in position relative to the hollow column part, and the machining requirement is high; once machining deviation occurs, the smooth installation of the permanent magnet is affected.

[0005] In the existing permanent magnet motor for a refrigerant compressor, the slot-pole number of the stator and the rotor is usually 9 slots and 6 poles or 6 slots and 4 poles, and the permanent magnet is a rare earth permanent magnet; the rare earth permanent magnet has high cost and large price fluctuation; and it is found in production practice that the spoke type rare earth permanent magnet synchronous motor with the slot-pole ratio has the disadvantage of large magnetic leakage.

[0006] In view of the above technical deficiencies of the prior art, the application aims to provide a permanent magnet motor for a refrigerant compressor, which has small harmonic loss, small magnetic leakage and low cost, and has good installation freedom and reliable fixation of the permanent magnet.

[0007] To this end, the application provides the following technical scheme:

[0008] ​​​The refrigerant compressor permanent magnet motor comprises a permanent magnet rotor, a stator core, winding frames fixed at two ends of the stator core, and windings wound on the stator teeth and the winding frame teeth and accommodated in the stator slots, and the permanent magnet rotor is composed of a rotor inner core, a plurality of permanent magnets, a plurality of rotor core blocks arranged radially on the outer periphery of the rotor inner core, and end covers fixed at two ends of the rotor core blocks, and the improvement is that the rotor inner core is provided with rotor shaft holes in the center and arc-shaped slots uniformly arranged at the outer periphery, the arc-shaped slots are convex arcs, and a convex rib is formed between adjacent arc-shaped slots, each rotor core block is integrally composed of a sector part and a handle part, the outer edge of the handle part is a convex arc surface, the rotor core blocks are connected to the arc-shaped slots of the rotor inner core one by one through the handle parts, the convex arc surface is movably matched with the arc-shaped slot, wherein each rotor core block is composed of a plurality of laminated sector core pieces, each sector core piece is integrally composed of a sector piece and a handle piece, the outer edge of the handle piece is a convex arc edge, and the convex arc edge is a convex arc; a plurality of circumferentially spaced protrusions are axially extended from the inner wall of the outer edge of each end cover, the permanent magnets are arranged in the accommodating slots between adjacent rotor core blocks one by one, and each permanent magnet is installed between the convex rib and the protrusion; the permanent magnets are strip-shaped ferrite magnetic steels, there are 10 ferrite magnetic steels, and the stator slots of the stator core have 12 stator slots.

[0009] In order to improve the radial limiting effect, the central angle of each arc-shaped slot is 190°-270°, the central angle of each convex arc surface is 190°-270°, and the central angles of the two are equal.

[0010] Further, the central angle of each arc-shaped slot is 199°, and the central angle of each convex arc surface is 199°.

[0011] After the optimization design, the limiting performance of the rotor core block is improved, and the torque transmission is more reliable.

[0012] The end cover is fixed by a rivet axially penetrating through each rotor core block.

[0013] Each end cover is provided with a supporting flange part axially extended from the shaft hole of the outer wall.

[0014] On the basis of the shaft hole of the end cover for supporting the rotor shaft, the supporting flange part is designed, and the end cover increases the contact area for supporting the rotor shaft.

[0015] The rotor inner core is an aluminum alloy rotor inner core, an epoxy resin rotor inner core, or an engineering plastic rotor inner core.

[0016] The present application has the following advantages and positive effects:

[0017] The refrigerant compressor permanent magnet motor is matched by 12 slots and 10 poles, ensures that the motor back electromotive force waveform is sinusoidal, thereby reducing the loss caused by harmonics, and the leakage magnetic field is small, wherein, the permanent magnet rotor adopts ferrite material to replace the rare earth permanent magnet, and the rare earth resource is no longer occupied, and the motor output power and motor performance are close to or even reach the rare earth permanent magnet synchronous motor after testing, and the price of ferrite magnetic steel is only less than 10% of the rare earth permanent magnet, and the cost advantage is that the applicant inquires the Shanghai non-ferrous metal network price release platform recently, the accounting unit price of ferrite magnetic steel used in the current radial permanent magnet synchronous motor is only 2.8 yuan / block, and the accounting unit price of rare earth permanent magnet used in the rare earth permanent magnet synchronous motor is as high as 32 yuan / block; The ferrite magnetic steel is fixed by the simple end cover, the positioning is reliable, and the stability is good during high-speed rotation.

[0018] The concave-convex arc surface movable cooperation structure of the sector body and the handle part meets the certain angular movement adjustment freedom of each rotor core block relative to the rotor inner core, so that the cooperation requirement of the rotor core block and the rotor inner core is low, the installation freedom is good, the punching processing error of the sector core piece is compensated, and the stacking riveting processing error of the rotor core block is compensated; Since the rotor core is composed of the rotor inner core and a plurality of split rotor core blocks, correspondingly, the smallest unit of the rotor core block, i.e. the area of the sector core piece, is small, so that the sector core piece can be punched on the small area of the electrical steel material, and the sector core piece can be punched by using the remaining material of the electrical steel sheet, and the material utilization rate is high, so that the material cost is reduced. BRIEF DESCRIPTION OF DRAWINGS

[0019] Figure 1 Fig. 1 is a perspective view of the refrigerant compressor permanent magnet motor shown in the embodiment;

[0020] Figure 2 Fig. 5 is a perspective view of the permanent magnet rotor of the application, 5(a) is a perspective view, and 5(b) is a cross-sectional view;

[0021] Figure 3 Fig. 1 is a perspective view of the refrigerant compressor permanent magnet motor shown in the embodiment;

[0022] Figure 4 Fig. 5 is a perspective view of the permanent magnet rotor of the application, 5(a) is a perspective view, and 5(b) is a cross-sectional view;

[0023] Fig. 5 is a perspective view of the permanent magnet rotor of the application, 5(a) is a perspective view, and 5(b) is a cross-sectional view;

[0024] Figure 6 Fig. 5 is a perspective view of the permanent magnet rotor of the application, 5(a) is a perspective view, and 5(b) is a cross-sectional view;

[0025] Figure 7 Fig. 5 is a perspective view of the permanent magnet rotor of the application, 5(a) is a perspective view, and 5(b) is a cross-sectional view;

[0026] Figure 8is a perspective view of the inner core of the present invention;

[0027] Figure 9 is a perspective view of a rotor core block of the present invention;

[0028] Figure 10 is an end view of the rotor core of the present invention;

[0029] Figure 11 It is a plan view of the sector-shaped core sheet of the present invention. [Specific implementation method]

[0030] See also Figures 1-11 As shown, a permanent magnet motor for a refrigerant compressor includes a permanent magnet rotor, a stator core 11, a winding frame 12 fixed to both ends of the stator core, a winding 13 wound around the stator teeth 111 and the winding frame teeth 121 and accommodated in the stator slots 112, and the permanent magnet rotor is composed of a rotor core 2, a plurality of permanent magnets 4, a plurality of rotor core blocks 3 radially arranged on the outer periphery of the rotor core 2, and end covers 5 fixed to both ends of the rotor core blocks 3. The improvement is that the rotor core 2 has a rotor shaft hole 200 at its center and arc slots 20 are evenly spaced on its outer peripheral side, and as shown in the figure The arc groove 20 is a superior arc surface, and the transition between adjacent arc grooves 20 forms a convex rib 21. Each rotor core block 3 is composed of a sector body portion 31 and a sector handle portion 30. The outer edge of the sector handle portion 30 is a convex arc surface 300. The rotor core blocks 3 are connected to the arc groove 20 of the rotor inner core 3 one by one through the sector handle portion 30. The convex arc surface 300 is movably matched with the arc groove 20. Each rotor core block 3 is riveted together by multiple sector iron core sheets 3a. Each sector iron core sheet 3a is composed of a sector sheet 31a and a sector handle sheet 30a. The outer edge of the sector handle sheet 30a is a convex arc edge 300a. Figure 11 The convex arc edge 300a shown is a major arc; on the outer edge of each end cover 5, circumferentially spaced protrusions 50 extend axially from the inner wall, and the permanent magnets 4 are arranged one by one in the accommodating grooves 31a between adjacent rotor core blocks 3, and each permanent magnet 4 is installed between the rib 20 and the protrusion 50; the permanent magnets 4 are bar-shaped ferrite magnets, there are 10 ferrite magnets, and the stator core 11 has 12 stator slots 112.

[0031] The specifications of the rotor core blocks 3 are the same; the specifications of the permanent magnets 4 are the same; and the specifications of the end covers 5 are the same.

[0032] FIG5( b ) shows that the outer side of the permanent magnet 4 is located on the outer circle surrounded by the rotor core block 3 (see FIG5( b ) Figure 7 , the central vertex of the fan top surface of each rotor core block 3 and its fan body portion 31 has been drawn with a dotted line. After the protrusion 50 blocks the permanent magnet 4, the outer wall of each protrusion 50 is located on the outer circle shown by the above dotted line.

[0033] The convex arc side 300a is a major arc, and the convex arc surface 300 is also a major arc surface.

[0034] In order to prevent magnetic leakage from the permanent magnet synchronous motor, the rotor inner core 2 is made of non-magnetic conductive material, and the rotor core block 3 is made of magnetic conductive electrical steel.

[0035] In a specific implementation, the rotor inner core 2 is an aluminum alloy rotor inner core, an epoxy resin rotor inner core, or an engineering plastic rotor inner core; and there are 10 rotor core blocks 3 .

[0036] See Figure 11 、 6 As shown, the inner end of each permanent magnet 4 contacts the transition edge 30a-31a connecting the handle piece 30a and the face piece 31a, forming a limit for the permanent magnet 4 installed in the receiving groove 31a, so that a gap is left between each permanent magnet 4 and the facing rib 20. Figure 3 5(b)], the gap is conducive to increasing the magnetic resistance, and can further reduce the leakage flux on the basis of using ferrite magnets as the permanent magnets.

[0037] As a preferred embodiment, the central angle α of each arcuate groove 20 is 190° to 270°, the central angle δ of each convex arcuate surface 300 is 190° to 270°, and the central angles of the two are equal.

[0038] In further implementation, the central angle α of each arc-shaped groove 20 is 199°, and the central angle δ of each convex arc-shaped surface 300 is 199°.

[0039] The end cover 5 is fixed by rivets 6 that axially pass through the axial through holes 310 of each rotor core block 3.

[0040] Each end cover 5 has a supporting flange portion 51 extending axially from the axial hole on its outer wall.

[0041] The sector-shaped core sheets 3a are provided with rivet holes 310a. After the sector-shaped core sheets 3a are stacked and riveted to obtain the rotor core blocks 3, axial through holes 310 are formed on the rotor core blocks 3. After the permanent magnets 4 are inserted between adjacent rotor core blocks 3, end covers 5 are installed at both ends of the rotor core, and then rivets 6 are inserted and riveted, and the rotor shaft is installed to obtain a fully assembled permanent magnet rotor, which is used for an inner rotor type permanent magnet synchronous motor.

Claims

1. A permanent magnet motor for refrigerant compressor, comprising a permanent magnet rotor, a stator core, wire frames fixed at both ends of the stator core, and windings wound around the stator teeth and the wire frame teeth and accommodated in the stator slots, the permanent magnet rotor being composed of a rotor inner core, a plurality of permanent magnets, a plurality of rotor core blocks arranged radially at the outer periphery of the rotor inner core, and end covers fixed at both ends of the rotor core blocks, The rotor inner core is provided with rotor shaft holes in the center and arc grooves at the outer circumferential side in uniform intervals, and the arc grooves are hyperarc surfaces, and the convex ribs are formed between adjacent arc grooves, each rotor core block is composed of a sector part and a handle part, the outer edge of the handle part is a convex arc surface, the rotor core blocks are connected to the arc grooves of the rotor inner core one by one through the handle parts, the central angle of each arc groove is 190°-270°, the central angle of each convex arc surface is 190°-270°, and the central angles of the two are equal, wherein, each rotor core block is composed of a plurality of fan-shaped core pieces riveted together, each fan-shaped core piece is composed of a fan piece and a handle piece integrally, the outer edge of the handle piece is a convex arc-shaped edge, and the convex arc-shaped edge is a superior arc, the permanent magnets are arranged in the accommodating slots between the adjacent rotor core blocks one by one, the permanent magnets are bar-shaped ferrite magnetic steels, there are 10 ferrite magnetic steels, the stator core has 12 stator slots, and the end covers are fixed by rivets axially penetrating through the rotor core blocks, characterized in that the convex arc-shaped surface is movably matched with the arc-shaped slot, the inner end of each permanent magnet is in contact with the transition surface between the handle part and the fan part, the permanent magnet accommodated in the accommodating slot is limited, so that there is a gap between each permanent magnet and the facing convex rib, and a circumferentially spaced convex projection is axially extended from the inner wall of each end cover.

2. The permanent-magnet electric motor for a refrigerant compressor according to claim 1, characterized by The central angle of each arc-shaped slot is 199°, and the central angle of each convex arc-shaped surface is 199°.

3. The permanent-magnet electric motor for a refrigerant compressor according to claim 1, characterized by A supporting flange part is axially extended from the shaft hole of the outer wall of each end cover.

4. The permanent-magnet electric motor for a refrigerant compressor according to claim 1, characterized by: The rotor inner core is an aluminum alloy rotor inner core, an epoxy resin rotor inner core, or an engineering plastic rotor inner core.

Images