JP2013099180A - Case of rotary electric machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the assemblability of a coolant pipe sandwiched and supported by a case body, which forms a case housing a rotary electric machine, and a case cover.SOLUTION: A through hole 40 is provided at a portion of a case cover 26 which an end of a coolant pipe 32 faces. A screw plug 42 for pressing the coolant pipe 32 and fixing and supporting the coolant pipe 32 in a case is screw-coupled to the through hole 40. The structure allows an operator to visually check the coolant pipe 32 through the through hole 40 and check the position of the coolant pipe 32 even if the case cover 26 is attached to a case body.

Description

  The present invention relates to a case that houses a rotating electrical machine, and more particularly to the structure of the case.

  An electric motor that converts electrical energy into rotational kinetic energy, a generator that converts rotational kinetic energy into electrical energy, and an electric device that functions as both the motor and the generator are known. Hereinafter, these electric devices are referred to as rotating electric machines.

  There is known a rotating electrical machine housed in a closed space in a case. The following patent document shows a hybrid vehicle drive unit in which two rotating electric machines, a planetary gear mechanism, a speed reduction mechanism, a final speed reduction mechanism, and the like are provided in a common case. In this unit, the case is provided with a coolant pipe for sending a coolant for cooling the coil end of the rotating electrical machine. More specifically, the rotating electrical machine is disposed in an internal space formed by the case body and the cover. The coolant pipe is held so that both ends thereof are in contact with the case and the cover, and are sandwiched between the case body and the cover. In particular, the end of the coolant pipe on the cover side is supported so as to fit in a recess provided in the cover.

JP 2007-209160 A

  In assembling the coolant pipe into the case in the drive unit of Patent Literature 1, first, one end of the coolant pipe is inserted into a receiving portion provided at a predetermined position of the case body. While covering the cover in this state, the other end of the coolant pipe is pushed by the cover, and the coolant pipe is sandwiched between the case body and the cover, and this is fixedly held. In the process of attaching the cover to the case body, the coolant pipe is covered by the cover and the case body, and thus the coolant pipe cannot be directly visually observed. For this reason, there is a possibility that the coolant pipe cannot be assembled at the proper position.

  An object of the present invention is to easily achieve that the coolant pipe is assembled in a proper position.

  The case of the rotating electrical machine according to the present invention has a through-hole formed in a case cover that forms an internal space in which the rotating electrical machine is disposed together with the case main body, and the case cover is covered with the case main body after the case cover is put on the case main body. The position of the coolant pipe located at can be confirmed. The case body is provided with a receiving portion into which one end of the coolant pipe is fitted, and a through hole is provided at a position of the case cover facing the other end of the coolant pipe. A pressing member that presses the coolant pipe toward the case body is provided at a position where the through hole is provided.

  The pressing member may be fixed to the through hole.

  The pressing member may be a screw plug that is screw-coupled to the through hole and closes the through hole.

  Further, the screw plug can have a protrusion inserted into the coolant pipe at a portion facing the coolant pipe.

  Furthermore, the coolant pipe can be made of resin.

  Even when the case cover is placed on the case main body, the position of the internal coolant pipe can be confirmed through the through hole opened in the case cover.

It is principal part sectional drawing of the transaxle of this embodiment. It is a figure which shows the other structural example of a through-hole and its periphery.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a cross-sectional view of a main part of a transaxle 12 integrated with a rotating electrical machine 10 mounted on a hybrid vehicle or the like. The transaxle is a device in which a transmission and a final reduction gear are integrated, and a transmission mechanism and a final reduction mechanism including a differential device are housed in a common transaxle case. In a hybrid vehicle, an example in which one or a plurality of rotating electric machines are housed in the transaxle case is known. The rotating electrical machine housed in the transaxle cannot be expected to be cooled by outside air, and the cooling functions as a working fluid for operating the lubricating oil and the hydraulic cylinder belonging to the speed change mechanism, like other mechanisms such as the speed change mechanism. Done by liquid. Hereinafter, this liquid is referred to as a cooling liquid.

  The rotating electrical machine 10 includes a substantially cylindrical rotor 14 and a substantially cylindrical stator 16 disposed so as to surround the periphery of the rotor 14. The rotor 14 and the stator 16 are disposed coaxially. In FIG. 1, the common central axis extends in the vertical direction further on the left side from the illustrated range. Therefore, the illustrated range of the rotating electrical machine 10 is a part of the outer periphery. The rotor 14 has a rotor core 18 formed by laminating magnetic steel plates in the direction of the central axis, and a permanent magnet (not shown) is disposed inside a cylindrical outer peripheral surface or in the vicinity of the outer peripheral surface. The stator 16 has a stator core 20 that is formed by laminating magnetic steel plates in the form of an annular plate on the inner peripheral surface of the annular plate and having a comb-like shape along the circumferential direction in the direction of the central axis. The magnetic steel plates forming the stator core 20 are laminated so that the unevenness thereof is aligned, whereby convex portions serving as magnetic poles are arranged along the circumferential direction on the inner peripheral surface of the stator core 20. The coil 22 is formed by winding a conducting wire around the magnetic pole. The conducting wire exits from the space called the slot between the magnetic poles toward the end face of the stator core 20, extends in the circumferential direction, and enters another slot. This is repeated to form the coil 22. A portion of the coil 22 that protrudes from the end face of the stator core is called a coil end.

  The rotating electrical machine 10 is disposed in an internal space 28 formed by the case body 24 and the case cover 26. The case body 24 may be a part of the transaxle case. In this case, a recess in which the rotating electrical machine 10 is accommodated is formed in the transaxle case, and a portion constituting the recess becomes the case body 24. The case body 24 has an opening 30, and the above-described case cover 26 covers the opening 30. By arranging the case cover 26 so as to cover the opening 30 of the case body 24, the case body 24 and the case cover 26 define the internal space 28. The rotating electrical machine 10 is disposed in the internal space 28. The case body 24 and the case cover 26 constitute a case for housing the rotating electrical machine.

  The rotating electrical machine 10 employs a liquid cooling method in which a cooling liquid is sent to a predetermined portion in order to improve the cooling performance. A flow path for sending the coolant is provided in the case. For example, the flow path is formed by making a hole in the constituent member of the case main body 24, and is formed by a tubular material such as a pipe or a hose that is retrofitted as a part of the case.

  In the internal space 28, a coolant pipe 32 made of, for example, resin for sending the coolant is disposed. One end of the coolant pipe 32 is inserted into a receiving hole 34 provided in the case body 24. The receiving hole 34 is connected to a coolant flow path 36 formed in the case body 24. A step 38 is formed at the boundary between the receiving hole 34 and the coolant flow path 36, and the end of the coolant pipe 32 abuts on the step 38 to prevent the coolant pipe 32 from being inserted further into the bag. Is done. The coolant flow path 36 guides the coolant sent by a pump (not shown) to the coolant pipe 32. The pump may be a pump dedicated to cooling the rotating electrical machine 10. Moreover, the pump which sends a cooling fluid to each mechanism in the transaxle 12 may be sufficient, and a cooling fluid is a liquid which functions also as lubricating oil or a working fluid as mentioned above.

  The coolant pipe 32 is arranged in parallel with the rotating electrical machine 10 and extends from the receiving hole 34 toward the case cover 26. A through hole 40 that penetrates the case cover 26 is formed in a portion of the case cover 26 that faces the coolant pipe 32. Even when the case cover 26 is covered by the through hole 40, the inside of the case, in particular, the end of the coolant pipe 32 can be seen from the outside of the case. The through hole 40 can be closed with a screw plug 42. The screw plug 42 has a head portion 44 and a shaft portion 46. A hexagonal hole for turning the screw plug 42 is formed in the head portion 44, and a male screw is formed on the peripheral surface of the shaft portion 46.

  A female screw is cut on the peripheral surface of the through hole 40, and the male screw of the screw plug 42 is screwed to fix the screw plug 42 to the through hole 40. A protrusion 48 is formed at the tip of the screw plug 42, that is, at the end of the shaft portion 46 opposite to the head portion 44. The protrusion 48 is inserted into the opening at the end of the coolant pipe 32 and positions the end of the coolant pipe 32 on the case cover 26 side. The protrusion 48 may block the opening of the coolant pipe 32. At least a part of the protrusion 48 can be tapered, and the tapered shape pushes the coolant pipe 32 toward the case body 24 when the screw plug 42 is screwed. Further, the cooling liquid pipe 32 is extended from the example shown in FIG. 1, and the end of the cooling liquid pipe 32 is brought into contact with the end surface 50 of the shaft portion 46 of the screw plug 42. You may make it do. In this case, the protrusion 48 is shaped so as not to impede contact with the end surface 50 of the coolant pipe 32.

  A discharge hole 52 for discharging the coolant is provided on the side surface of the coolant pipe 32, particularly at a position facing the coil end of the coil 22, from which the coolant sent by the pump is directed toward the coil end. Discharged. When the transaxle 12 of this embodiment is in use, the right direction in FIG. 1 is downward, and the coolant discharged from the discharge hole 52 falls to the coil end and cools the coil.

  The assembly process of the rotating electrical machine 10 will be described. First, the rotating electrical machine 10 is fixed at a predetermined position in the case body 24. Next, the coolant pipe 32 is inserted into the receiving hole 34. Then, the opening 30 of the case main body is covered with a case cover 26 and fixed to the case main body 24 by a fastening element such as a bolt. At this time, the through hole 40 is in an open state. The coolant pipe 32 is visually observed through the through hole 40 to confirm whether the coolant pipe 32 is located at a predetermined position, for example, the center of the through hole 40. If it is deviated, a tool or the like is inserted from the through hole 40 to adjust the position. After confirmation or position adjustment, the screw plug 42 is screwed into the through hole 40. By screwing the screw plug 42, the protrusion 48 is inserted into the hollow portion of the coolant pipe 32, and the coolant pipe 32 is pressed in the direction of the receiving hole 34. Thereby, the coolant pipe 32 is fixedly supported on the case. Further, when the screw plug 42 is turned to fix, the protrusion 48 at the tip of the screw plug is inserted into the coolant pipe 32, so that the coolant pipe 32 is not displaced in a direction perpendicular to the pipe axial direction. .

  As an aspect of the receiving hole 34, it can also be comprised in a taper shape. First, when the coolant pipe 32 is inserted into the receiving hole 34, the coolant pipe 32 is weakly supported, and the position of the end of the coolant pipe 32 on the case cover side is easily moved. After aligning the cover side end of the coolant pipe 32, the coolant pipe 32 is pushed into the receiving hole 34 by the screw plug 42, and the coolant pipe 32 is supported more strongly by the tapered shape of the receiving hole 34. To do.

  In addition, as a mode of receiving the coolant pipe 32 on the case body 24 side, a circular wall standing on the bottom surface 54 of the case body 24 is provided, and the coolant pipe 32 is inserted into a portion surrounded by the wall. May be.

  As a mode of receiving the coolant pipe 32 on the case cover 26 side, a recess may be provided in the end face of the shaft portion 46 of the screw plug instead of the projection 48, and the coolant pipe 32 may be fitted in this recess.

  Further, as a mode of receiving the coolant pipe 32 on the case cover 26 side, a stepped through hole may be formed and the coolant pipe 32 may be received through the through hole. Specifically, as shown in FIG. 2, a through hole 56 having a large diameter portion and a small diameter portion is formed in the case cover 26 so that the coolant pipe 32 is inserted into the large diameter portion. The screw plug 58 does not have a portion that engages with the coolant pipe 32 such as the protrusion 48 described above.

  In the configuration example of FIG. 2, when fixing the case cover 26 to the case body, the case cover 26 presses the coolant pipe toward the receiving hole 34 of the case body. After inserting the coolant pipe 32 into the receiving hole 34, the case cover 26 is covered while viewing the coolant pipe 32 from the through hole 56. By visually observing the coolant pipe 32 through the through hole 56, it can be confirmed whether the coolant pipe 32 is fitted in a predetermined position, that is, the large diameter portion of the through hole 56. After covering the case cover 26, the case cover 26 is fastened to the case body 24 with bolts or the like. At this time, the coolant pipe 32 is pressed and fixed at a predetermined position at the step end face 60 which is a boundary between the large diameter portion and the small diameter portion of the through hole 56.

  Instead of the stepped through hole 56, a circular wall having an inner diameter larger than the through hole may be provided so as to surround the periphery of the through hole, and the end of the coolant pipe 32 may be received inside the wall. .

  According to the above-described embodiment, the coolant pipe 32 can be visually observed when the case cover is put on, so that it is possible to prevent the coolant pipe 32 from being assembled in a shifted state. If the coolant pipe is difficult to deform, it can be seen that there is resistance when the cover is assembled or it cannot be assembled, and the position of the coolant pipe is shifted, but the coolant pipe is made of resin etc. If it is easy to do, even if the coolant pipe is assembled in a deformed state, this may not be known. According to the above-described embodiment, since the coolant pipe can be visually observed through the through-hole even after the case cover is put on, it is possible to avoid being assembled in a misaligned state.

  Further, by engaging the protrusion at the tip of the screw plug with the coolant pipe, it is possible to prevent the coolant pipe from being displaced while the screw plug is being rotated.

  10 Rotating machine, 14 Rotor, 16 Stator, 22 Coil, 24 Case body, 26 Case cover, 28 Internal space, 32 Coolant pipe, 34 Receiving hole, 42, 58 Screw plug, 48 Projection.

Claims (6)

A case that houses a rotating electrical machine,
A case cover that forms an internal space together with the case body in which the case body and the rotating electrical machine are disposed;
One end fits into a receiving portion provided in the case body, and the other end is located in the vicinity of the case cover, a coolant pipe for sending coolant,
Have
A through hole is formed at a position of the case cover facing the other end of the coolant pipe,
Furthermore, at the position of the through hole, a pressing member that presses the coolant pipe toward the case body,
Case of rotating electrical machine.   The rotary electric machine case according to claim 1, wherein the pressing member is fixed to the through hole.   The case of the rotating electrical machine according to claim 2, wherein the pressing member is a screw plug that is screw-coupled to the through hole and closes the through hole.   4. The rotating electrical machine case according to claim 3, wherein the screw plug has a protrusion inserted into the coolant pipe at a portion facing the coolant pipe. 5.   The rotating electrical machine case according to any one of claims 1 to 4, wherein the coolant pipe is made of resin. A case that houses a rotating electrical machine,
A case cover that forms an internal space together with the case body in which the case body and the rotating electrical machine are disposed;
Have
The case body is provided with a pipe receiver that receives one end of a coolant pipe for sending coolant,
The case cover is provided with a through hole at a position facing the other end of the coolant pipe,
Furthermore, at the position of the through-hole, it has a pressing member that presses the coolant pipe toward the case body,
Case of rotating electrical machine.

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