JP2010288373A - Partition member for motor cooling - Google Patents

Abstract

A partition member for cooling an electric motor capable of preventing a refrigerant in a stator housing chamber from leaking into a rotor housing chamber with a simple configuration.
An electric motor cooling partition member (17) that divides a stator storage chamber (20) for storing a stator (11) and a rotor storage chamber (30) for storing a rotor (12), wherein the partition wall member (17) is formed by winding reinforcing fibers (171). Made of cylindrical fiber reinforced plastic.
[Selection] Figure 2

Description

  The present invention relates to a partition member for cooling an electric motor that divides a stator accommodating chamber that accommodates a stator and a rotor accommodating chamber that accommodates a rotor.

  Conventionally, for example, a rotating electrical machine described in Patent Document 1 is known as a rotating electrical machine having a cooling structure for cooling a stator. As shown in FIGS. 10 and 11, the rotating electrical machine 200 includes a stator 205 in which a coil 204 is mounted on a stator core 203 in which slots 201 and teeth 202 are alternately formed on an inner peripheral surface, and an inner peripheral portion of the stator 205. And a rotatable rotor 206, a stator 205, and a housing 207 that accommodates the rotor 206.

Further, as a structure for cooling the stator 205, a plate 208 that closes the slot 201 is disposed in the vicinity of the opening of the slot 201, and molds are disposed on the inner peripheral side and the outer peripheral side of the plate 208 and the stator core 203, and resin is provided there. Partition walls 209 and 209 are formed between both ends of the stator 205 and the side walls 212 and 212 of the housing 207, and the housing 207 has a stator housing chamber 210 for housing the stator 205 and a rotor housing chamber for housing the rotor 206. It is divided into 211.
In addition, it is described that a cooling refrigerant is introduced into the housing 207 from the introduction port 213 formed in the stator housing chamber 210, the refrigerant is led out to the outside through the outlet port 214, and the stator 205 is cooled.

JP 2003-61285 A

However, in the rotating electrical machine 200 described in Patent Document 1, when the stator core 203 has a laminated structure in which magnetic plates are laminated, the refrigerant introduced into the stator accommodating chamber 210 may leak into the rotor accommodating chamber 211 from the gap between the laminates. there were. When the leaked refrigerant adheres to the rotor 206, the mechanical loss increases, and when the refrigerant is discharged from the rotor accommodating chamber 211 to the outside, a separate discharge mechanism is required.
Further, since the partition walls 209 and 209 at both ends of the plate 208 are formed by filling a resin using a mold, the structure is complicated and the manufacturing process is also complicated.

  The present invention has been made in view of the circumstances described above, and an object thereof is to provide a partition member for cooling an electric motor that can prevent the refrigerant in the stator housing chamber from leaking into the rotor housing chamber with a simple configuration. It is in.

In order to achieve the above object, the invention described in claim 1
A stator housing chamber (e.g., stator housing chamber 20 in the embodiment described later) and a rotor housing chamber (e.g., rotor 12 in the embodiment described later) for housing a stator (e.g., stator 11 in the embodiment described later). An electric motor cooling partition member (for example, a partition member 17 in an embodiment described later) that divides (e.g., a rotor accommodating chamber 30 in an embodiment described later),
The partition member is made of a cylindrical fiber reinforced plastic formed by winding a fiber (for example, a reinforcing fiber 171 in an embodiment described later).

In addition to the configuration of the invention described in claim 1, the invention described in claim 2
The winding direction of the fiber is inclined with respect to the central axis of the partition member.

In addition to the configuration of the invention described in claim 1 or 2, the invention described in claim 3
The fiber is made of alumina fiber or glass fiber,
The winding direction of the fibers is inclined by ± 50 ° to ± 80 ° with respect to the central axis of the partition member.

In addition to the configuration of the invention according to any one of claims 1 to 3, the invention according to claim 4
The fiber reinforced plastic matrix resin (for example, a matrix resin 172 in an embodiment described later) is made of bismaleimide resin or epoxy resin.

In addition to the structure of the invention in any one of Claims 1-4, the invention of Claim 5 is
The partition member is formed by a filament winding molding method.

According to the first aspect of the present invention, the partition that divides the stator housing chamber and the rotor housing chamber is constituted by one cylindrical partition member, and the partition member is supported in a liquid-tight manner by the housing. The refrigerant in the storage chamber can be prevented from leaking into the rotor storage chamber. Thereby, the mechanical loss by a refrigerant | coolant adhering to a rotor can be reduced, and efficiency can be improved. Further, since there is no need to provide a discharge mechanism for discharging the refrigerant from the rotor housing chamber to the outside, the rotating electrical machine can be reduced in size.
Furthermore, since the partition member is made of fiber reinforced plastic, the strength can be ensured against the pressure from the outside in the radial direction by the refrigerant. Thus, the torque and efficiency of the rotating electrical machine can be improved by reducing the thickness of the partition member, and the cooling capacity can be improved while avoiding an increase in the size and weight of the rotating electrical machine.

  According to the invention of claim 2, since the winding direction of the fibers is inclined with respect to the central axis of the partition wall member, it is possible to further improve the strength.

  According to the invention of claim 3, the fibers are made of alumina fibers or glass fibers, and the winding direction of the fibers is inclined by ± 50 ° to ± 80 ° with respect to the central axis of the partition wall member, thereby further improving the strength. Can be achieved. In addition, since the fibers are formed of a nonmagnetic and nonconductive material, even if the partition member is disposed between the stator and the rotor, the rotating magnetic field can be inhibited and heat generation based on eddy current can be prevented.

  According to the invention of claim 4, since the fiber reinforced plastic matrix resin is made of a bismaleimide resin or an epoxy resin, the strength can be further improved without affecting the magnetic properties.

  According to the invention of claim 5, since the partition member is formed by the filament winding molding method, the strength can be further improved.

It is an axial sectional view of an embodiment of a rotating electrical machine provided with a partition member according to the present invention, and is a sectional view taken along line II in FIG. FIG. 2 is a cross-sectional view in the direction perpendicular to the axis of the rotating electrical machine shown in FIG. 1. It is an axial sectional view explaining the deformation mode of the partition member in the rotating electrical machine shown in FIG. It is a schematic diagram explaining the inclination angle and forming method of the fiber with respect to the central axis of the partition member. It is a perspective view of the partition member which attached the strain gauge used for the pressure test. It is a figure which shows a pressure | voltage resistant test apparatus, (a) is an axial orthogonal direction sectional view of a pressure | voltage resistant test apparatus, (b) is the BB sectional drawing of (a). It is a figure which shows the deformation | transformation of the partition member in a pressure | voltage resistant test apparatus. It is a graph which shows the pressure | voltage resistant test result of Examples 1-4. It is a graph which shows the pressure | voltage resistant test result of Examples 1-5 and Comparative Examples 1 and 2. FIG. 3 is an axial sectional view of a rotating electrical machine described in Patent Document 1. FIG. FIG. 6 is a partial cross-sectional view in a direction perpendicular to the axis of a stator of a rotating electrical machine described in Patent Document 1.

  Hereinafter, each embodiment of the rotating electrical machine according to the present invention will be described in detail with reference to the accompanying drawings.

  The rotating electrical machine 10 according to the present embodiment includes, for example, as shown in FIGS. 1 and 2, a stator 11, a rotor 12 that is disposed to face the inner peripheral side of the stator 11 via an air gap S, and the stator 11 and the rotor. And a housing 13 that accommodates the housing 12.

  The housing 13 includes a cylindrical cylindrical wall portion 131, side wall portions 132 and 132 in which both sides of the cylindrical wall portion 131 are liquid-tightly closed via O-rings 14 and 14, and axially inner sides of the side wall portions 132 and 132. An annular support portion 133 that is joined and has a smaller diameter than the cylindrical wall portion 131 and a shorter axial length is formed. The cylindrical wall 131 is provided with an introduction port 131a for introducing a refrigerant from the outside to the inside of the housing and an outlet port 131b for drawing the refrigerant from the inside of the housing to the outside. The stator 11 is fixed to the inner peripheral surface of the cylindrical wall 131.

  The stator 11 is wound around each of the teeth 111 of the stator core 110 and the stator core 110 in which a plurality of teeth 111 protruding at a predetermined interval are provided on the inner diameter side, and the teeth 111 and the slots 112 are alternately formed in the circumferential direction. The coil 114 is configured. The stator core 110 is configured by laminating a plurality of layers of electromagnetic steel plates.

  The rotor 12 includes a rotor core 120 that can rotate integrally with the rotary shaft 15, and permanent magnets (not shown) that are arranged in the rotor core 120 at equal intervals in the circumferential direction. The rotating shaft 15 is rotatably supported on the side wall portions 132 and 132 of the housing 13 via bearings 16 and 16, and the rotor core 120 generates a reaction force against the rotating magnetic flux applied by the stator core 110 and It can rotate as a unit.

  Here, in the rotating electrical machine 10 according to the present embodiment, one cylindrical partition member 17 is provided in the air gap S formed between the inner peripheral surface of the stator 11 and the outer peripheral surface of the rotor 12. The inner peripheral surface of each part is supported by the annular support parts 133 and 133 of the housing 13 via O-rings 18 and 18.

  The partition member 17 is made of a fiber reinforced plastic in which a nonmagnetic and nonconductive reinforcing fiber 171 is covered with a matrix resin 172. It is preferable to use alumina fiber or glass fiber as the reinforcing fiber 171 and use a bismaleimide resin, a polyfunctional epoxy resin or a normal epoxy resin with high heat resistance as the matrix resin 172. As the glass fiber, high-strength glass fiber is preferable. For example, S-2 glass manufactured by AGY, T-glass manufactured by Nittobo, etc. can be used. The reinforcing fibers 171 are preferably helically wound so as to be inclined with respect to the central axis O of the partition member 17, and more preferably manufactured by a filament winding (FW) molding method. Assuming that the inclination angle of the reinforcing fiber 171 with respect to the central axis O of the partition wall member 17 shown in FIG. 4 is θ, the inclination angle θ is preferably ± 50 ° to ± 80 °, and more preferably about ± 70 °. If it is ± 50 ° or more, since the cross-sectional rigidity is high, the possibility of crushing due to external pressure can be further reduced, and if it is ± 80 ° or less, the axial restraint force is high, so that the possibility of bending due to external pressure and breakage is further increased. Can be reduced. Moreover, according to the filament winding molding method, pressure resistance and heat resistance can be improved.

  The partition member 17 has an axial length substantially equal to the distance between the side wall portions 132, 132 of the housing 13 facing in the axial direction, and the thickness (radial length) is an air gap so as to ensure a predetermined strength. The thickness is set to be shorter than S.

Here, with reference to FIG. 4, the manufacturing method of the partition member 17 by a filament winding (FW) shaping | molding method is demonstrated.
A metallic mandrel 173 having a predetermined inner diameter of the partition member 17 is prepared in advance. A solvent-free polyfunctional epoxy resin blended to obtain heat resistance is prepared as matrix resin 172, and AG-2 S-2 glass fiber as reinforcing fiber 171 impregnated with this resin is applied to mandrel 173. The laminated layers are wound so as to have an angle of ± 70 ° with respect to the central axis O (θ in FIG. 4).
This winding is repeated, and when the glass fiber layer impregnated with the polyfunctional epoxy resin reaches a predetermined thickness, the winding is stopped and the wound glass fiber layer is sealed with a polypropylene film.
In this sealed state, the polyfunctional epoxy resin is cured in an atmosphere of 150 ° C. × 20 hours, and the mandrel 173 is removed by a predetermined decentering machine. As a result, an annular body made of fiber-reinforced plastic in which the reinforcing fiber 171 is wound at ± 70 ° with respect to the central axis O can be obtained.
Thereafter, the sealed polypropylene film is peeled off, and the outer surface is machined to a predetermined thickness, whereby the partition member 17 is completed.

  The outer peripheral surface of the partition wall member 17 manufactured in this way is in-fit with a tooth front end surface 111 a that is an inner peripheral surface of the tooth 111. The partition member 17 functions as a partition that divides the interior of the housing 13 into a stator housing chamber 20 that houses the stator 11 and a rotor housing chamber 30 that houses the rotor 12, and the inner peripheral surface of the partition member 17 and the annular support portion 133, The stator housing chamber 20 is liquid-tightly isolated from the rotor housing chamber 30 by O-rings 18, 18 provided between 133.

  Then, an insulating refrigerant is supplied from an inlet 131a formed in the cylindrical wall 131 of the housing 13, and the stator 11 is cooled by filling the stator housing chamber 20 with the refrigerant. At this time, the deformation mode of the cylindrical partition member 17 is distributed load bending with both ends supported as shown in FIG.

  As described above, according to the rotating electrical machine 10 of the present embodiment, the partition wall that divides the stator housing chamber 20 and the rotor housing chamber 30 is composed of one cylindrical partition wall member 17, and the partition wall member 17 is attached to the housing 13. Since it is supported in a liquid-tight manner, the refrigerant in the stator housing chamber 20 can be prevented from leaking into the rotor housing chamber 30 with a simple configuration. Thereby, the mechanical loss by a refrigerant | coolant adhering to the rotor 12 can be reduced, and efficiency can be improved. Further, since there is no need to provide a discharge mechanism for discharging the refrigerant from the rotor housing chamber 30 to the outside, the rotating electrical machine 10 can be reduced in size.

  Furthermore, since the partition member 17 is made of fiber reinforced plastic, it is possible to ensure strength against pressure from the outside in the radial direction due to the refrigerant. Thus, by reducing the thickness of the partition member 17, the torque and efficiency of the rotating electrical machine 10 can be improved, and the cooling capacity can be improved while avoiding an increase in the size and weight of the rotating electrical machine 10. Therefore, even if the refrigerant flow rate is increased to improve the cooling performance, deformation and destruction of the partition wall member 17 can be avoided.

  Further, since the winding direction of the reinforcing fibers 171 constituting the partition wall member 17 is inclined with respect to the central axis O of the partition wall member 17, the strength can be further improved. Therefore, the partition member 17 can reduce the wall thickness of the partition member as compared with the case where a member having the same pressure resistance is used as the partition member. Therefore, the air gap S between the rotor 11 and the stator 12 can be reduced. Torque and efficiency can be improved. Further, by reducing the air gap S between the rotor 11 and the stator 12, the physique in the radial direction can be reduced and the dimensions and weight can be reduced as compared with a rotating electrical machine that outputs the same torque.

  Further, according to the rotating electrical machine 10 of the present embodiment, the reinforcing fiber 171 is made of alumina fiber or glass fiber, and the winding direction of the reinforcing fiber 171 is ± 50 ° to ± 80 ° with respect to the central axis O of the partition wall member 17. By inclining, the strength can be further improved. Further, since the reinforcing fiber 171 is formed of a nonmagnetic and nonconductive material, even if the partition member 17 is disposed between the stator 11 and the rotor 12, obstruction of the rotating magnetic field and generation of heat based on eddy currents are prevented. can do.

  Further, according to the rotating electrical machine 10 of the present embodiment, since the matrix resin 172 constituting the partition member 17 is made of bismaleimide resin or epoxy resin, the strength can be further improved without affecting the magnetic characteristics. Can do.

  Further, according to the rotating electrical machine 10 of the present embodiment, when refrigerant is supplied to the stator housing chamber 20, hydraulic pressure acts on the outer peripheral surface of the partition wall member 17 by the coolant, but the O-rings 18 and 18 are connected to the partition wall member 17. Since it abuts on the inner peripheral surface, the fluid pressure of the refrigerant acts in the direction of crushing the O-rings 18 and 18, so that the sealing performance can be improved.

Next, a pressure resistance test of the cylindrical partition member will be described with reference to FIGS.
As shown in FIG. 5, a cylindrical partition member Sa is prepared as a test sample, and four strain gauges (A to D, E to C) are equally spaced circumferentially on both sides in the axial direction of the inner peripheral surface of the partition member Sa. H) was pasted. As shown in FIGS. 6A and 6B, the test apparatus 40 includes a cylindrical portion 41 having a diameter larger than that of the partition wall member Sa and protruding portions that protrude from the inner peripheral surface of the cylindrical portion 41 and are provided at equal intervals in the circumferential direction. A cylindrical member 43 having 42 and shaft members 44 and 44 provided at both ends in the axial direction and opposed to each other are configured to be able to supply a refrigerant therein. Then, the partition member Sa is attached to the test apparatus 40, and the outer peripheral surface of the partition member Sa is fitted into the protrusions 42 corresponding to the teeth, and the inner peripheral surface of the partition member Sa is liquid-tightened by O-rings 45 and 45. The shaft members 44 and 44 at both ends in the axial direction were fixed. Thus, the partition member Sa was mounted on the test apparatus 40, the refrigerant was supplied to the space on the outer peripheral side of the partition member Sa, and the strain of the partition member Sa was examined.

  Measurement was performed using seven samples (Examples 1 to 4 and Comparative Examples 1 to 3) shown in Table 1 as the partition member Sa. The shape of all the partition members Sa was φ48 × 150 mm, the wall thickness was 0.5 mm, and the pressure until the partition member Sa broke was examined by repeatedly holding for 30 seconds after raising the refrigerant oil temperature to 120 ° C. and 50 kPa. Table 2 shows material property values of the reinforcing fibers.

FIG. 7 schematically shows a process of breaking the partition wall member Sa in the pressure resistance test.
As shown in FIG. 7A, when no oil pressure is applied, the partition wall member Sa having a substantially perfect circular cross section gradually deforms as shown in FIGS. 7B to 7D by increasing the oil pressure. A process was observed. In a state where the hydraulic pressure is relatively low, compressive stress is applied to all four strain gauges as shown in FIG. 7B, and when the hydraulic pressure is gradually increased, as shown in FIG. 7C. Tensile stress was applied at one location. Further, as shown in FIG. 7 (d), the partition wall member Sa was damaged from the tensile stress generating portion in FIG. 7 (c) by further increasing the hydraulic pressure.
From this pressure resistance test result, when an external pressure is applied to the partition wall member Sa, the deformation behavior in a minute region due to a variation in thickness is triggered in the process in which the partition wall member Sa is isotropically compressed due to an increase in hydraulic pressure. As a result, it was found that the deformation of the cylinder became non-uniform, and as a result, the partition wall member Sa was damaged from the tensile stress generation part.

8 and 9 are graphs of the pressure resistance test results. FIG. 8 shows a measured pressure resistance value obtained by repeatedly measuring each of Examples 1 to 4 three times and an average value thereof, and the vertical axis represents the withstand voltage (kPa). FIG. 9 shows the average values of Examples 1 to 4 shown in FIG. 8 and the measurement results of Comparative Examples 1 to 3, with the vertical axis representing the withstand pressure (kPa) and the horizontal axis representing the heat resistant temperature (° C.). Is. The pressure resistance temperature indicates the heat resistant temperature of the resin material.
Here, if the pressure resistance and heat resistant temperature required for the rotating electrical machine 10 are 450 KPa and 120 ° C., respectively, the first to fourth embodiments sufficiently satisfy these pressure resistance and heat resistant temperature in the partition member Sa having a thickness of 0.5 mm. However, the PPS injection molding material containing 30% glass fiber of Comparative Example 1 did not satisfy the pressure resistance and heat resistance temperature, and the PEEK injection molding material containing 30% glass fiber of Comparative Example 2 did not satisfy the pressure resistance. Moreover, although the comparative example 3 satisfy | filled the pressure | voltage resistance and the heat-resistant temperature once, it was not satisfied at the point of a proof pressure.

  From the above measurement results, it was found that the pressure resistance is improved as compared with the injection molded material by using a fiber reinforced plastic formed by winding reinforcing fibers by a filament winding molding method as the partition wall member Sa.

  Further, the partition member formed to be inclined with respect to the central axis O of the partition member 17 as compared with the partition member Sa (Comparative Example 3) having an inclination angle of 0 ° / 90 ° with respect to the central axis O of the partition member Sa. It was found that Sa (Examples 1 to 4) improved pressure resistance.

  Further, it was found that the pressure resistance is improved by using alumina fiber having a higher elastic modulus than the glass fiber as the reinforcing fiber material, and the pressure resistance is improved when the inclination angle is ± 70 ° rather than ± 55 °. Further, when the damaged part is visually observed, alumina fiber is more reinforcing fiber material than glass fiber, and the inclined part is less than ± 55 ° and ± 70 ° is less damaged, and the deformation at the time of damage is also less. Inferred.

In addition, this invention is not limited to what was illustrated to the said embodiment, In the range which does not deviate from the summary of this invention, it can change suitably.
For example, in the above-described embodiment, the partition wall member 17 is fitted in the tooth tip surface 111a with an inlay, but the partition member 17 is not necessarily fitted in the tooth tip surface 111a, and the outer peripheral surface of the partition member 17 and the tooth tip surface A predetermined gap may be provided between 111a. Thereby, it is not necessary to strictly manage the outer diameter of the partition member 17, and the manufacture of the partition member 17 can be facilitated.

DESCRIPTION OF SYMBOLS 10 Rotating electrical machine 11 Stator 110 Stator core 111 Teeth 111a Teeth front end surface 112 Slot 114 Coil 12 Rotor 13 Housing 131a Inlet 131b Outlet 133 Annular support 17 Partition member 171 Reinforcing fiber (fiber)
172 Matrix resin 173 Mandrel 18 O-ring 20 Stator accommodating chamber 30 Rotor accommodating chamber S Air gap

Claims (5)

A partition member for cooling an electric motor that divides a stator accommodating chamber for accommodating a stator and a rotor accommodating chamber for accommodating a rotor,
The partition member for cooling an electric motor, wherein the partition member is made of a cylindrical fiber reinforced plastic formed by winding fibers.   The partition member for cooling an electric motor according to claim 1, wherein a winding direction of the fibers is inclined with respect to a central axis of the partition member. The fiber is made of alumina fiber or glass fiber,
The partition member for cooling an electric motor according to claim 1 or 2, wherein a winding direction of the fibers is inclined by ± 50 ° to ± 80 ° with respect to a central axis of the partition member.   The partition member for cooling an electric motor according to any one of claims 1 to 3, wherein the fiber reinforced plastic matrix resin is made of bismaleimide resin or epoxy resin.   The partition member for cooling an electric motor according to claim 1, wherein the partition member is formed by a filament winding molding method.

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