JP2011217437A - Stator for rotary electric machine - Google Patents

Abstract

An object of the present invention is to allow a coolant of a rotating electric machine to sufficiently come into contact with a coil.
A rotation axis of a rotor of a rotating electrical machine extends in a lateral direction. The filling member 34 is inserted into the gap 30 between the stator core 20 and the coil end 28 of the stator 16 of the rotating electrical machine, and the gap 30 is filled. The coolant guided by the cooling pipe 32 is supplied from above so as to be applied to the stator 16, particularly the coil end 28. The supplied coolant is prevented from entering the gap 30 by the filling member 34 and flows along the outer peripheral surface of the coil end 28. The time for the coolant to contact the coil end 28 is increased, and the cooling performance is improved.
[Selection] Figure 1

Description

  The present invention relates to a structure of a stator of a rotating electrical machine that performs cooling with a liquid.

  A hybrid vehicle including an internal combustion engine and a rotating electric machine is known as a prime mover. The rotating electrical machine functions as an electric motor that generates power for driving the vehicle, and also functions as a generator that converts kinetic energy of the vehicle into electric energy during braking. Below, the motor | power_engine which can exhibit the function of both an electric motor and a generator is described and described as a rotary electric machine. A power device for a hybrid vehicle in which a rotating electric machine is integrated with a transaxle or transmission of an internal combustion engine has been put into practical use. In this power unit, the rotating electrical machine is housed in a case such as a transaxle, and cannot be directly cooled by outside air, but is cooled via lubricating oil such as a transaxle or a working liquid.

  A stator of a rotating electrical machine includes a substantially cylindrical stator core in which convex portions (teeth) serving as magnetic poles are arranged in the circumferential direction on an inner peripheral surface, and a coil formed by winding a conductive wire around the teeth. There is a gap between the coil end, which is a portion of the coil protruding from the end face of the stator core, and the stator core, from which cooling liquid enters the annular coil end. The liquid that has entered the gap does not contribute to the cooling of the coil, and if it further enters the gap between the stator and the rotor, it becomes a resistance to the rotation of the rotor.

  Patent Document 1 below discloses a technique for applying a resin to the entire coil end or a part thereof. The gap between the coil end and the stator core is filled with resin.

JP 2001-119883 A

  In Patent Document 1, since the whole or a part of the coil end is covered with resin, the contact area between the coil end and the cooling liquid is reduced, and the cooling efficiency is not good. Moreover, since it is necessary to apply | coat and harden resin, a process becomes long.

  An object of the present invention is to provide a stator core of a rotating electrical machine in which a clearance between a coil end and a stator core that has good cooling efficiency and can be created by a simple operation is filled.

  The rotating electrical machine according to the present invention is arranged such that the rotation axis of the rotor extends in the lateral direction, and the stator of the rotating electrical machine is cooled by being applied with a coolant from above. The stator of this rotating electrical machine has a stator core having teeth serving as magnetic poles, and a coil formed by winding a conductive wire around the teeth. The coil includes a coil end that is a portion protruding from an end surface of the stator core in the rotation axis direction. In the upper half of the stator, a filling member is inserted into a gap between the stator core and the coil end, and this gap is filled.

  By preventing the coolant applied from above the stator from entering the gap between the stator core and the coil end by the filling member, the coolant flows more to the coil end and the cooling performance is improved. The filling member is inserted, and the process is simplified as compared with the case of applying, curing, and the like.

It is a figure which shows the rotary electric machine cooled by the liquid. It is the figure which looked at the rotary electric machine of FIG. 1 from the rotating shaft direction. It is a figure which shows the shape of a stator core. It is the figure which looked at the coil end and the stator core of the vicinity from the radial direction outer side of the rotary electric machine. It is a figure which shows the shape of a filling member. It is a figure which shows the modification of a filling member.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following, description will be made using a rotating electrical machine housed in a transaxle of a hybrid vehicle. However, the present invention can be widely applied to a rotating electrical machine that cools by applying a liquid to a stator. FIG. 1 is a view of a rotating electrical machine 12 provided in a transaxle case 10 as viewed from a direction orthogonal to the rotation axis of a rotor 14. FIG. 2 is a view as seen from the rotor rotation axis direction. The rotating electrical machine 12 is disposed such that the rotation axis of the rotor 14 extends in the lateral direction. A cylindrical stator 16 as a whole is disposed around the rotor 14. In FIG. 1, the stator 16 is shown in cross section. The stator 16 includes a stator core 20 having teeth 18 (see FIG. 3) arranged on the inner circumferential surface of the cylinder at intervals in the circumferential direction, and a coil 22 formed by winding a conductive wire around the teeth 18. FIG. 3 is a view of the stator core 20 viewed from the same direction as FIG. 2. A gap formed between adjacent teeth 18 is called a slot 24, and a conductive wire 26 (see FIG. 4) is placed in the slot 24. Be placed. The conducting wire 26 is disposed so as to extend through the paper surface of FIG. 3, further extends from the end surface of the stator core 20, and bends toward the other slot 24. In this way, the conductive wire 26 is wound around the teeth 18 to form the coil 22. A portion outside the end face of the stator core 20 of the coil 22, that is, a portion 28 that bridges between the slots 24 is called a coil end.

  FIG. 4 is a view of the coil end 28 and the stator core 20 in the vicinity thereof as seen from the direction orthogonal to the rotor rotation axis. When the conductive wire 26 extending from the slot in the stator core 20 exits from the slot 24, the conductive wire 26 extends in the same direction as it is, then bends and extends substantially along the circumferential direction, and enters another slot 24. Immediately before entering, the conductor 26 has a portion extending in a direction corresponding to the direction extending into the slot 24. As shown in the figure, a gap 30 is formed between a portion of the coil end 28 extending in the substantially circumferential direction and the stator core 20. The gap 30 extends along the teeth 18 and forms a tunnel that connects the inside and the outside of the coil end 28 having an annular shape as a whole.

  Returning to FIG. A cooling pipe 32 serving as a flow path for supplying a cooling liquid (hereinafter referred to as a cooling liquid) is disposed above the rotating electrical machine 12. The flow path may have a bowl shape instead of the pipe shape. As the coolant, lubricating oil or working fluid of hydraulic equipment in the transaxle can be used in the transaxle. The coolant is supplied from the cooling pipe 32 to the upper part of the coil end 28. If there is a gap 30 between the coil end 28 and the stator core 20, the coolant applied to the coil end 28 from above flows through the gap 30 to the inside of the coil end 28. At this time, the cooling liquid does not sufficiently contact the conductive wire extending in the circumferential direction of the coil end 28 and does not sufficiently contribute to cooling of the coil. Further, a part of the coolant that has flowed inside the coil end 28 enters the gap between the rotor 14 and the stator 16, and becomes resistance to rotation of the rotor 14. As described above, the coolant flowing through the gap 30 toward the inside of the coil end 28 is not preferable, and it is desirable to eliminate or reduce the coolant.

  In the rotating electrical machine 12 of the present embodiment, the filling member 34 is inserted so as to fill the gap 30 formed between the coil end 28 and the stator core 20, thereby preventing the coolant from flowing inside the coil end 28. is doing.

  FIG. 5 shows the shape of the filling member 34 as viewed from the axial direction. The filling member 34 has a semicircular arc shape, and slits 36 are arranged in the circumferential direction on the inner peripheral side thereof. The slit 36 corresponds to the slot 24 of the stator core 20 and is positioned so as to overlap the slot 24. The conducting wire 26 exiting from the slot 24 passes through the slit 36. A portion between the slits 36 is a portion to be inserted into the tunnel-shaped gap 30, and this portion is hereinafter referred to as an insertion portion 38. The filling member 34 is attached to the upper half of the stator. The filling member 34 is a circular arc having a central angle slightly smaller than a semicircle, for example, a central angle of about 120 °, as long as the cooling liquid is allowed to enter the inside of the coil end 28. Also good.

  The arc-shaped filling member 34 is made of a sufficiently flexible material such as rubber or resin. When the arc-shaped filling member 34 is attached to the coil end 28, the arc-shaped filling member 34 is extended so that the insertion portion 38 is inserted into the gap 30. The filling member 34 is returned to the arc shape while being mounted between the coil end 28 and the stator core 20. When the filling member 34 is mounted, the gap 30 is filled and the coolant supplied from above is prevented from entering the gap 30. For this reason, as shown by arrows 40 and 42 in FIG. 2, it flows along the outer peripheral surface of the coil end 28 and flows downward. Thereby, it can contact with the conducting wire 26 of a coil end for a long time, and can take away the heat | fever sufficiently.

  In order to improve the mounting property of the filling member 34 to the coil end 28, the width of the insertion portion 38 can be made smaller than the tooth width. Further, the filling member 34 may be divided into several parts. In addition, as shown in FIG. 6, a clip 44 made of a flexible material may be arranged at the entrance of the slot 34 to prevent the filling member 34 from coming off.

  The filling member 34 inserts a previously molded member into the gap 30, but injects a highly viscous fluid into the gap 30 and further continuously fills the outer portion of the gap 30 in the circumferential direction. A member having the same shape as the filling member 34 may be formed on the spot.

  12 rotating electrical machines, 14 rotors, 16 stators, 18 teeth, 20 stators, 22 coils, 24 slots, 28 coil ends, 30 cooling pipes, 32 filling members.

Claims (1)

A rotating electrical machine arranged with the rotor axis of rotation extending in the lateral direction, and being cooled by cooling liquid applied from above,
A stator core having teeth serving as magnetic poles;
A coil formed by winding a conductive wire on the teeth, and a coil including a coil end that is a portion protruding from an end surface of the stator core in the rotation axis direction;
In the upper half of the stator, a filling member that is inserted into a gap between the stator core and the coil end to fill the gap,
A stator for a rotating electrical machine.

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