JP6072199B1 - Rotating electric machine - Google Patents

Abstract

When cooling oil is supplied from the inside of a rotor toward a stator winding for cooling, if the flow rate of the cooling oil is increased to increase the cooling performance, the gap between the inner periphery of the stator and the outer periphery of the rotor is increased. In some cases, the cooling oil stays and the loss torque due to the increase in the fluid resistance increases, thereby deteriorating the efficiency of the rotating electrical machine. A stator core, a slot portion formed between the stator cores, a stator winding in which a linear winding portion is inserted into the slot portion and wound around the stator core, and a side surface of the stator winding A stator having an insulating paper with a radially inner end edge folded back with a protrusion of the stator core as a boundary and an radially inner end extending to the inner surface of the stator winding The rotor has a rotor core and a cooling oil supply path that supplies the cooling oil to the gap, and is arranged in a gap with the rotor core. A cooling oil passage is formed by a triangular space portion having two inclined sides of the folded portion of the insulating paper. [Selection] Figure 5

Description

  The present invention relates to a rotating electrical machine that performs cooling by scattering cooling oil supplied from the inside of a rotor to a stator winding.

In conventional rotating electrical machines, a cooling structure using various methods such as water cooling and oil cooling is generally adopted to increase the heat generation during energization of the stator windings. Cooling using a water channel is performed, and in the case of oil cooling, there are many examples of cooling using oil for transmission and gear cooling.
Patent Document 1 discloses a method for cooling a stator winding by directly supplying cooling oil to a stator winding from a flow path provided in a motor casing. It has been reported that the cooling effect is improved by supplying cooling oil to the position of the winding.
In Patent Document 2, in the cooling mode in which the cooling oil is scattered to the coil end, the inclined portion is provided in a part of the axial direction of the core armature to prevent the cooling oil from staying between the gaps, thereby ensuring the cooling performance. In addition, a method for preventing an increase in loss torque due to fluid resistance between gaps is disclosed.

JP 2009-261214 A Japanese Patent Laid-Open No. 2015-15851

When a cooling method for supplying cooling oil from the inside of the rotor toward the coil end of the stator as in Patent Document 1 is adopted as a cooling method for the rotating electrical machine, the flow rate of the cooling oil is increased in order to increase the cooling performance. There is a problem that the cooling oil stays in the gap between the inner periphery of the stator and the outer periphery of the rotor, the loss torque due to the increase in fluid resistance is increased, and the efficiency of the rotating electrical machine is deteriorated.
In addition, a rotating electrical machine using an oil cooling structure has a problem of preventing an increase in loss torque due to cooling oil entering a gap between an inner periphery of a stator and an outer periphery of the rotor. If only a part of the shape of the amateur is changed in the axial direction, the strength and shape of the entire core may be complicated, which may affect the lamination strength and the press die. Due to the difference, the influence on the torque characteristics due to the change of the magnetic characteristics can be considered.
This invention uses a simple structure to prevent the cooling oil from staying in the gap between the inner peripheral side of the stator and the outer peripheral side of the rotor, thereby preventing an increase in loss torque due to an increase in fluid resistance. An object of the present invention is to provide a rotating electrical machine that suppresses the efficiency reduction of the rotating electrical machine.

A rotating electrical machine according to the present invention includes a plurality of stator cores protruding radially inward of the rotor shaft and arranged in the circumferential direction, and a slot portion formed between the stator cores adjacent to each other, A stator winding in which a linear winding portion is inserted into the slot and wound on each of the stator cores, and covers the outer surface of the linear winding portion of the stator winding, and the radially inner end edge portion A stator having an insulating paper that is folded back at the protrusions at both corners of the front end surface of the stator core and has a radially inner end extending to the inner surface of the linear winding portion of the stator winding, And a rotor having an outer peripheral surface arranged to maintain a gap with each of the front end surfaces of the stator core and rotatably supported, and having a magnet and a cooling oil supply path for supplying cooling oil to the gap, In each communication portion between each slot and the gap, A cooling oil passage that forms a triangular cross-sectional space having a bottom surface and two folded sides of the insulating paper that are adjacent to each other and facing each other in the axial direction of the rotor. Is formed.

  According to the rotating electrical machine of the present invention, the cooling oil flows into the gap between the rotor and the stator by creating a space portion in the flow path portion where the cooling oil enters from the gap into the slot portion by the core tip and the insulating paper. Even if the cooling oil is allowed to flow into this space, the cooling oil does not stay, and even if a part of the cooling oil flows, it is easily discharged, thus preventing an increase in loss torque due to fluid resistance. be able to. In addition, the insulating paper can prevent not only the insulation performance between the windings on the inner peripheral side but also the discharged iron powder or the like from adhering to the winding portion to deteriorate the insulation.

It is sectional drawing which shows the internal structure of the rotary electric machine in Embodiment 1 of this invention. It is a perspective view which shows the stator of the rotary electric machine in Embodiment 1 of this invention. It is a perspective view which shows the stator winding | coil of the rotary electric machine in Embodiment 1 of this invention. (a) is a perspective view which shows a part of structure of the stator inner peripheral part and rotor outer peripheral part of a rotary electric machine in Embodiment 1 of this invention, (b) is the insulating paper after assembling | attaching to a rotary electric machine. It is the perspective view shown alone. (a) is a cross-sectional view schematically showing the slot portion of the inner peripheral portion of the stator and the vicinity of the outer peripheral portion of the rotor in Embodiment 1 of the present invention, and (b) is a part of FIG. Sectional drawing which expanded and showed, (c) is the perspective view which showed a part of stator core. It is sectional drawing which simplified and showed the shape which looked at the insulating paper which covered the stator winding | coil of the rotary electric machine in Embodiment 1 of this invention to the axial direction. It is a perspective view which shows a part of structure of the rotor outer peripheral part which has a stator inner peripheral part and shallow groove | channel in Embodiment 2 of this invention.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
In addition, the same code | symbol shows the same or an equivalent part between each figure.

Embodiment 1 FIG.
Hereinafter, the rotating electrical machine according to the first embodiment will be described with reference to FIGS. 1 to 6.
1 is a sectional view showing an internal configuration of a rotating electrical machine according to Embodiment 1 of the present invention, FIG. 2 is a perspective view showing a stator of the rotating electrical machine, and FIG. 3 is a perspective view showing a stator winding of the rotating electrical machine. 4 (a) is a perspective view showing a part of the configuration of the stator inner peripheral portion and the rotor outer peripheral portion of the rotating electrical machine, (b) is a perspective view showing the insulating paper after being assembled to the rotating electrical machine alone, FIG. 5A is a cross-sectional view schematically showing the slot portion of the inner peripheral portion of the stator of the rotating electrical machine and the vicinity of the outer peripheral portion of the rotor, and FIG. 5B is an enlarged view of a part of FIG. Sectional view, (c) is a perspective view showing a part of the stator core, FIG. 5 is a sectional view in the vicinity of the slot portion of the stator inner periphery and the rotor outer periphery, and FIG. 6 covers the stator winding. It is sectional drawing which looked at the insulating paper to the axial direction.

  As shown in FIG. 1, the rotating electrical machine 1 includes a stator 4 and a rotor 3, and cooling oil (not shown) is directed from the inside of the rotor 3 toward the coil end 43 e of the stator 4 by centrifugal force during rotation. And the stator winding 43 is cooled.

The rotor 3 has a rotor core 32 made of laminated steel plates disposed on the outer peripheral side thereof, and a permanent magnet (field magnet) 33 disposed therein. Further, the rotor core 32 is fixed by being press-fitted into the outer periphery of the rotor boss portion 31, and is rotatable with respect to the housing 2 by the bearing 5 disposed on the inner periphery of the rotor boss portion 31. It is supported.
Further, the rotor 3 is arranged with its outer peripheral surface maintaining a predetermined gap G1 from each front end surface of the stator core (described later), and from the gap G1 toward the coil end portion (described later) of the stator winding. And a cooling oil supply passage 34 for supplying the cooling oil.

As shown in FIG. 2, the stator 4 is configured by press-fitting a stator core 42 made of a laminated steel plate similar to the rotor core 32 into the inner periphery of a ring-shaped frame 41.
The plurality of stator cores 42 have protrusions 42a that protrude inward in the radial direction of the drive shaft (rotor shaft) 21 and are arranged in the circumferential direction, and extend in the circumferential direction from both corners of the tip surface. .

  The stator 4 includes a slot portion 44 formed between adjacent stator cores 42 and a fixed portion in which a linear winding portion is inserted into the slot portion and is wound around the stator core 42 in a concentrated manner. A stator winding 43 and an insulating paper 45 covering the outer surface of the linear winding portion of the stator winding are provided. The insulating paper 45 will be described later.

  In addition, the power distribution component 10 is disposed on the end face of the stator core 42. Electric power is supplied to the stator winding 43 from the external harness via the power distribution component 10 to generate a rotating magnetic field, thereby driving the rotor 3 and generating the generated torque to the drive shaft (rotor shaft) 21. It has a transmission structure.

  Further, the stator 4 is configured inside the power distribution component 10 by joining the terminal wire 18 of the stator winding 43 to the power distribution component 10 disposed on the stator core 42 as shown in FIG. Electrical connection to the bus bar is made. Driving a rotating electrical machine by generating a rotating magnetic field in the stator winding 43 by energizing a power supply terminal portion protruding from a bus bar built in a terminal block having an electrical connection with each UVW phase bus bar. Is possible.

  The stator winding 43 is wound around the insulator 17 attached to the stator core 42, and includes coil ends 43e that are formed to protrude from the end face of the stator core 42 and have curved shapes at both ends in the axial direction. Yes. After the final turn portion 43t of the stator winding 43 is straight-formed, the terminal wire 18 is entangled with the cutout portion 19 and fixed.

Next, an insulating paper 45 that covers the stator winding 43 and is a main part of the present invention will be described with reference to FIGS.
As shown in FIG. 4, the insulating paper 45 covers the periphery of the stator winding 43 while being sandwiched between the linear winding portions W of the adjacent stator windings 43 in the slot portion 44. The insulation between the ground is secured.

Further, the shape after assembling the insulating paper 45 covering the periphery of the stator winding 43 is as shown in FIG. 4B, but as shown in FIG. 5, both corners of the front end surface of the stator core 42 The projecting portion 42a projecting from the inner surface is folded back at a boundary (starting point) 45s, and its radially inner end extends between the inner surface of the linear winding portion of the stator winding and the insulator 17.
Further, the insulating paper 45 adjacent to each other forms a space portion G2 as shown by a triangular dotted line in each communication portion P between each slot portion 44 and the gap G1 as the folded portion. That is, a space portion G2 having a triangular cross section is formed in which the outer peripheral surface of the rotor 3 is the bottom side 3C, and the folded portions of the insulating paper adjacent to each other are the two oblique sides 45A and 45B. A cooling oil passage penetrating in the rotor axial direction is formed.

  The cooling oil for cooling the stator winding 43 is scattered toward the coil end 43e of the stator 4 by rotating the rotor 3 from a cooling oil storage (not shown) inside the rotor. Cool the wire directly. As the cooling oil, ATF (Automatic Transmission Fluid) that performs lubrication in the transmission of the vehicle is used. A part of the cooling oil scattered on the coil end 43e enters the gap G1 between the outer periphery of the rotor 3 and the inner periphery of the stator 4, but even if the cooling oil flows into the space G2 at this time, the gap G1 It does not stay, and even if it flows in part, it is easily discharged through the triangular cooling oil passage, so it is possible to prevent an increase in loss torque due to fluid resistance, resulting in a decrease in efficiency of the rotating electrical machine. Can be prevented.

  As shown in FIG. 6, the insulating paper 45 between the phases adjacent to each other is gently curved in a curved shape in which the rotor axial end portions 45 e reduce or widen the separation distance toward the axial tip portion. It has a rounded shape R (curved R portion), and its tip end portion is arranged closest to the central portion of both slot portions 44.

  As described above, the insulating paper 45 has a shape that gently warps toward both ends in the axial direction. When warped inward, the cooling oil scattered in the coil end 43e flows into the slot 44. It becomes difficult to stay in the gap G1, and if it warps outward, the opening formed at the tip becomes a shape that widens, which is advantageous for oil discharge, and cooling oil supply There is an effect that a part of the cooling oil protruding from the path 34 to the coil end is easily diffused in the axial direction after flowing into the opening.

The insulating paper 45 shown in FIG. 5 covers the entire stator winding portion, but is in close contact with the stator winding 43 via the insulator 46 having good thermal conductivity such as varnish on the inner peripheral side of the slot portion 44. doing. This close contact structure improves heat conduction and heat transfer, and can greatly improve cooling performance.
Further, the temperature of the insulating paper 45 is kept low by the cooling oil on the inner peripheral side of the slot, but the thermal resistance decreases as the contact state with the stator winding 43 as a heat source becomes better. The better the contact state, the more the increase in the maximum temperature of the stator winding 43 can be suppressed.

Embodiment 2. FIG.
Based on FIG. 7, the rotating electrical machine according to the second embodiment will be described.
FIG. 7 is a perspective view showing configurations of the stator 4 and the rotor 3 according to Embodiment 2 of the present invention. A plurality of shallow grooves 35 that widen the gap G1 are formed on the outer peripheral surface of the rotor 3 according to the second embodiment.

By providing the shallow groove 35 on the outer periphery of the rotating rotor 3, it becomes easy for the cooling oil to flow into the space portion G <b> 2 formed in the slot portion 44, and the range in which the cooling oil stays together with the space portion G <b> 2. Therefore, the effect of preventing the stagnation of the cooling oil in the gap G1 can be enhanced, and an increase in loss torque due to fluid resistance that occurs when the rotor 3 rotates at high speed can be prevented. The shallow groove 35 also has an effect of reducing gogging torque and suppressing torque pulsation in designing the magnetic circuit.
The other parts are the same as those in the first embodiment, and the description thereof is omitted.

  In the present invention, the embodiments can be appropriately modified and omitted within the scope of the invention.

1: rotating electric machine, 3: rotor, 31: rotor boss part, 32: rotor core,
33: Permanent magnet 34: Coolant oil supply passage for rotor 35: Shallow groove 4: Stator
41: Ring-shaped frame, 42: Stator core, 42a: Projection
43: Stator winding, 43e: Coil end, 44: Slot part,
45: insulating paper, 45e: both ends of the insulating paper 45 in the rotor axial direction,
45s: boundary (starting point), 45A, 45B: hypotenuse of insulating paper,
3C: base (outer peripheral surface of rotor 3), G1: gap,
G2: a triangular space section (cooling oil passage),
P: each communication part between the slot part and the gap,
R: Insulating paper 45 curved R portions at both ends of the rotor in the axial direction

Claims (4)

  A plurality of stator cores protruding radially inward of the rotor shaft and arranged in the circumferential direction, a slot portion formed between the stator cores adjacent to each other, and a linear winding portion in the slot portion Is inserted and the stator winding wound around each of the stator cores, covers the outer surface of the linear winding part of the stator windings, and the radially inner end edge is the tip surface of the stator core. A stator having insulating paper that is folded back at the projections at both corners and whose radially inner end extends to the inner surface of the linear winding portion of the stator winding, and the outer peripheral surface is the stator core And a rotor having a magnet and a cooling oil supply path for supplying cooling oil to the gap, the slot portions and the gaps being provided. Adjacent to each other, with the outer peripheral surface of the rotor as the bottom. A space portion having a triangular cross section with two folded sides of the folded portion of the insulating paper in an opposed state is formed, and a cooling oil passage penetrating in the axial direction of the rotor is formed by this space portion. A rotating electric machine that is characterized.   The rotor axially opposite ends of the insulating paper that are adjacent to each other are formed in a gentle curved shape that reduces or widens the separation distance toward the distal end in the axial direction. Item 2. The rotating electrical machine according to Item 1.   The rotating electrical machine according to claim 1, wherein the insulating paper is in close contact with the stator winding via an insulator.   The rotating electrical machine according to claim 1, wherein a plurality of shallow grooves that widen the gap are formed on an outer peripheral surface of the rotor.

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