JPH1127881A - Liquid-cooled rotating machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To surely remove air bank in a circulating path which can cool a stator. SOLUTION: A liquid reservoir 13 for discharge is provided with a pipe 17 as an air bleeding-cum-drainage means, and the opening at the other end of the pipe 17 is arranged at the highest section within a liquid reservoir 13 for discharge, so that an air bank can be discharged to the outside, without fail by leading the air bank positioned at the highest section within a liquid reservoir 13 for discharge from the opening at the other end of the pipe 17. Thus, even if air bank exists within the liquid reservoir 13 for discharge, it can be removed, consequently this machine can prevent the cooling effect with respect to the stator 8 from dropping, and can maintain a favorable cooling function.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid-cooled rotary machine for cooling a stator by flowing a cooling liquid through a stator of a motor unit, and more particularly to cooling a rotary machine having a rotor outside the stator. It concerns the device.

[0002]

2. Description of the Related Art A conventional liquid cooling rotary machine for cooling a stator disposed inside an outer rotor is disclosed in European Patent Publication No. 0623988A2. This liquid-cooled rotary machine uses water as a cooling liquid, and has a support shaft for rotatably supporting the outer rotor and a flow hole through which cooling water flows. The stator is fixed in contact with the outer periphery of the bearing shaft, and a flow path communicating with the flow hole is provided inside the stator. This circulation path is provided with at least one system, the one system constitutes an inflow pipe and a discharge pipe for the stator, and the cooling water passes through the inflow pipe from the outside through the flow path of the bearing shaft. A circulation system is adopted in which the cooling water flows into the stator and returns to the outside through the flow pipe of the bearing shaft through the outflow pipe.

[0003]

When the stator disposed inside the outer rotor is cooled by circulating cooling water, the cooling water is externally provided to the fixed member side as in the prior art. It is necessary to supply cooling water and discharge the cooling water to the outside thereof. Therefore, a cooling water discharge port is provided inside the water passage.

[0004] However, in the water channel constructed as described above, since the drain port is not located at the highest position in the water channel, the water channel is located at the highest position in the water channel in the operating state of the rotating machine. There is a problem that the air in the inside or the air mixed in the supply water stagnates, so that the cooling effect is significantly reduced. This problem is particularly significant when the cooling water is branched into a plurality of water passages.

SUMMARY OF THE INVENTION In view of the above-mentioned problems of the prior art, it is an object of the present invention to ensure that even if there is an air pocket in a flow path of a cooling liquid for cooling a stator, the air pool can be reliably removed. Is to provide a liquid-cooled rotating machine capable of maintaining a good temperature.

[0006]

According to the present invention, an outer rotor, a bearing shaft rotatably supporting the outer rotor, a stator fixed to the bearing shaft and arranged inside the outer rotor, A cooling device for cooling the stator with a cooling liquid, the cooling device comprising: a liquid inlet path for guiding external cooling liquid to the stator; and a discharge path for discharging the cooling liquid passing through the stator to the outside. And a flow path mechanism connected between the liquid inlet path and the discharge path, and for flowing the coolant through the stator, and the flow path mechanism transfers the coolant flowing through the stator to a downstream portion of the stator. It is characterized by having a discharge liquid sump stored at the end face, and an aerated cooling liquid discharge means for guiding a cooling liquid in the discharge liquid sump from a highest part in the discharge liquid sump to a discharge path.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. FIG. 1 is a sectional view of a main part showing a first embodiment of a liquid-cooled rotary machine according to the present invention, and FIG. 2 is a sectional view taken along line AA of FIG.

The liquid-cooled rotary machine according to the embodiment is applied to, for example, wheels mounted on a vehicle. As shown in FIG. 1, an outer rotor 1, a bearing shaft 6, and a stator 8 are combined. It is provided with.

The outer rotor 1 has a cylindrical rotor frame 2, a magnet 3 attached to the inner peripheral side thereof and made of a permanent magnet and the like, and fastening means 4 such as bolts attached to both axial ends of the rotor frame 2. And a fixed end bracket 5. The support shaft 6 has a cylindrical shape, and rotatably supports the outer rotor 1 via a bearing 7.

The stator 8 constitutes a motor section together with the outer rotor 1, is formed by mounting a coil on an iron core, is fixed to the outer peripheral portion of the support shaft 6, and is disposed inside the outer rotor 1. Have been. Then, by forming a magnetic circuit between the stator 8 and the magnet 3 of the outer rotor 1, the outer rotor 1 rotates around the axis of the stator 8.

The liquid-cooled rotating machine also has a cooling device for cooling the stator 8 with cooling water. The cooling device is roughly classified into a liquid inlet passage 9 for guiding cooling water from the outside to the stator 8, a discharge passage 10 for discharging the cooling water passing through the stator 8 to the outside, a liquid inlet passage 9 and a discharge passage. A flow path mechanism (not shown) connected between the paths 10 and for flowing the cooling water through the stator 8.

Here, the liquid inlet 9 is formed of a pipe, one end of which is connected to a cooling source (not shown) provided outside, and the intermediate position of which is connected to the bearing shaft 6 as shown in the figure.
The other end is connected to a hole 6b provided in the peripheral wall of the support shaft 6. The hole 6b is formed in the bearing shaft 6 at a position near one end (left side in FIG. 1) of the stator 8 along the radial direction. The discharge passage 10 is also made of a pipe like the liquid inlet passage 9, one end of which is connected to a hole 6 c provided on the peripheral wall of the support shaft 6, and the other end of which is connected to a hollow portion 6 a in the support shaft 6. It is inserted and connected to a cooling source. In addition, the pipes which respectively form the liquid inlet path 9 and the discharge path 10 may be inserted into these holes 6b and 6c.

On the other hand, the flow path mechanism includes an inlet liquid reservoir 11 for storing cooling water from the inlet channel 9 on one end surface side of the stator 8 in the axial direction, and a liquid reservoir for the inlet. A flow hole 12 through which the cooling water in the portion 11 flows through the stator 8;
The cooling water that has passed through the other end of the stator 8 (FIG. 1)
(Right side in FIG. 3), the discharge reservoir 13 stored on the downstream end face side, and cooling water in the discharge reservoir 13 are discharged from the highest part in the discharge reservoir 13 to the discharge path 10. And a draining / draining means for guiding the air to the air.

The liquid reservoir 11 is defined by a shielding member 15 mounted between the outer peripheral portion of the bearing shaft 6 and a side surface of one end of the stator 8 in the axial direction. Thus, the airtightness is provided so as to surround the hole 9 b of the liquid inlet passage 9 and the side surface of one end of the stator 8. In other words, the shielding member 15 has a substantially L-shaped cross section,
One end having a small diameter is airtightly fitted and fixed to the outer peripheral portion of the bearing shaft 6, and the other end having a large diameter is formed into a hole 6.
b is hermetically assembled to one end side face of the stator 8 in a state surrounding the b.

The flow hole 12 is formed in the stator 8 at a position inside the other end of the shielding member 15 so as to penetrate in the axial direction, so that the cooling water stored in the liquid inlet sump 11 is filled with the cooling water. To circulate and cool. This circulation hole 1
2 shows only one stator 2 formed straight along the stator axial direction in FIG. 1, but as shown in FIG.
A plurality of cooling water flows around the circumference of the stator 8 to enhance the cooling effect.

The drainage reservoir 13 is defined by a shielding member 16 mounted between the side surface of the other end of the stator 8 in the axial direction and the outer peripheral portion of the bearing shaft 6.
Thus, the airtight seal is provided so as to surround the downstream portion of the circulation hole 12 and the hole 6c of the discharge passage 10. That is, the shielding member 16 has a cylindrical shape symmetrical to the shielding member 15, and the stator 8 has a large-diameter end that surrounds the downstream portion of the flow hole 12 and the hole 6 c of the discharge passage 10. And the other end having a small diameter is fitted and fixed to the outer peripheral portion of the bearing shaft 6.

Accordingly, in this cooling device, when cooling water is sent from a cooling source (not shown), the cooling water accumulates in the liquid inlet reservoir 11 through the liquid inlet passage 9, and from there, the flow hole of the stator 8 flows. The liquid accumulates in the discharge-side sump 13 via the outlet 12 and is discharged to the outside through the discharge passage 10 therefrom.

Further, as shown in FIG. 1 and FIG. 2, the air release / drainage means is disposed in the drainage reservoir 13. That is, the draining / draining means is connected at one end to the hole 6c of the bearing shaft 6 connected to the discharge passage 10 and at the other end at the highest portion in the drainage reservoir 13. The pipe 17 is formed of a flexible pipe 17, and the air in the discharge sump 13 is guided to the discharge passage 10 together with the cooling water from the highest part in the sump 13 in the discharge sump 13. I have to.
That is, the pipe 17 has the other end opening at the drain port 1 in the rotating machine.
The air accumulated in the drainage reservoir 13 from here is guided to the discharge passage 10 together with the cooling water.

Since the liquid-cooled rotary machine of the embodiment has the above-described configuration, its operation will be described below. By forming a magnetic circuit between the stator 8 and the magnet 3 of the outer rotor 1, the entire outer rotor 1 rotates around the bearing shaft 6 and the stator 8. During this rotation, when cooling water is supplied by an external cooling source (not shown), the supplied cooling water temporarily accumulates in the liquid inlet reservoir 11 from the liquid inlet passage 9, and the accumulated cooling water is removed by the stator. After cooling the stator 8 through the flow hole 12 of the nozzle 8, the stator 8 is accumulated in the drainage reservoir 13. The cooling water accumulated in the drainage reservoir 13 is drained to the outside via the drain passage 10.

Here, during the initial flow of the cooling water, not only the air existing in the flow path is pushed by the cooling water and moves into the discharge reservoir 13 due to the cooling water, but also the cooling water. If the air mixed in the discharge liquid reservoir 13 collects and accumulates in the drain reservoir 13, the cooling effect of the stator 8 around that portion may be reduced.

However, in the embodiment, as described above, the discharge liquid reservoir 13 is provided with the pipe 17 as the air release / drainage means, and the other end opening of the pipe 17 is the most in the discharge liquid reservoir 13. Since it is located at a high position, the drainage sump 1
By guiding the air pool located at the highest position in 3 to the discharge path 10 together with the cooling water, the air pool can be reliably discharged to the outside, and therefore, the air pool is present in the discharge reservoir 13. Can be removed. As a result, the air pool can be reliably removed, so that the cooling effect on the stator 8 can be prevented from lowering, and a good cooling function can be maintained.

When the opening at the other end of the pipe 17 is located at the uppermost position in the drainage reservoir 13 as described above, the cooling water flowing into the pipe 17 is substantially filled. Therefore, the other end of the stator 8 can be cooled by the filled cooling water, and a large cooling action can be obtained in the stator radial direction. In addition, since the cooling water also accumulates in the liquid entry reservoir 11 formed at one end of the stator 8, the one end of the stator 8 can be similarly cooled. Therefore, the inside of the stator 8 is cooled by the circulation holes 12, and both ends of the stator 8 are also cooled by the liquid sump part 11 and the liquid sump part 13 for drainage. Can be further enhanced.

In the illustrated embodiment, a flexible pipe 17 is used as the air vent / drainage means, which is disposed in the discharge sump 13 on a radial plane.
Due to the pipe 17, the axial length in the drainage reservoir 13 can be reduced, and the axial space can be reduced accordingly. And flexible pipe 17
With the use of, it is easy to dispose it as shown in FIG. 2 and it is also possible to easily assemble it. Note that the pipe 17 is not limited to be flexible, and may be a pipe made of ordinary metal.

In the illustrated embodiment, the holes 6b and 6c forming one end of the liquid inlet passage 9 and the discharge passage 10 are formed in the peripheral wall of the bearing shaft 6 along the vertical direction. In this case, it is possible to reduce a decrease in the strength of the bearing shaft 6 when it is engaged. In particular, when a large weight acts on the bearing shaft 6 such as a vehicle, the holes 6b and 6c are formed in the bearing shaft 6 for example.
If it is pierced in the horizontal direction on the peripheral wall, the weight may act on the bearing shaft 6 and the strength may be reduced.
When formed as described above, it is possible to prevent the strength from being reduced despite the provision of the holes 6b and 6c in the support shaft 6.

FIG. 3 shows a second embodiment according to the present invention. The difference between this embodiment and the first embodiment is that
A connecting pipe 17 for connecting the highest portion in the drainage reservoir 13 and the drainage path 10 as an air release / drainage unit.
A in that it is composed of A.

That is, one end of the connecting pipe 17A is connected to a hole formed in the upper portion of the shielding member 16 defining the drainage reservoir 13, and the other end is drawn out to the outside of the shielding member 16. It is connected to one end of the discharge path 10. Therefore, one end of the discharge path 10 is provided with a hole 6 provided at a position outside the shielding member 16 on the peripheral wall of the bearing shaft 6.
c is inserted. In FIG. 3, the same parts as those of the first embodiment are denoted by the same reference numerals.

According to this embodiment, since it is basically the same as the first embodiment, the same operation and effect can be obtained.

FIG. 4 shows another embodiment according to the present invention. In this case, the first embodiment and the second embodiment are combined. That is, in addition to the connection pipe 17A serving as the air release / drainage means, a pipe 19 for guiding the cooling water in the drainage sump 13 to the outside is provided at the bottom of the drainage sump 13. The pipe 19 is formed in the same manner as the discharge passage 10 in the first embodiment, and is configured to guide the cooling water to the outside through the hole 6c 'communicating with the bottom in the discharge liquid sump portion 13. Description is omitted.

According to this embodiment, since the cooling water in the drainage reservoir 13 can be discharged by the connecting pipe 17A and the pipe 19, the flow rate can be increased without increasing the diameter of each pipe. it can. Therefore, if it is difficult to increase the diameter of the holes 6a, 6b, 6c 'with respect to the bearing shaft 6, or if the connecting pipe 17A cannot be made large due to space problems, the space can be saved, which is extremely effective. is there.

Further, for example, an opening / closing valve (not shown) is provided at an intermediate position of the connecting pipe 17A and the pipe 19, and the degree of opening thereof is adjusted by an external signal, whereby the flow rate of the cooling water can be adjusted. . Note that in each of the embodiments,
Although the example using the cooling water has been described, the same operation and effect can be obtained by using another liquid as the cooling medium.

[0031]

As described above, according to the first to third aspects of the present invention, the coolant circulating through the stator is stored in the space on the other end side of the stator in a substantially full state. The cooling liquid is guided from the highest part to the discharge path, so that even if there is an air pocket in the space, the air pool can be reliably discharged to the outside and removed, resulting in cooling the stator. It is possible to prevent the effect from lowering, and to maintain an excellent cooling function. In particular, according to the third aspect, the inside of the stator is cooled by the circulation holes, and both ends of the stator are also cooled by the liquid sump portion for liquid entry and the liquid sump portion for drainage. There is also an effect that can further enhance the effect.

[Brief description of the drawings]

FIG. 1 is a sectional view of a main part showing a first embodiment of a liquid cooling rotary machine according to the present invention.

FIG. 2 is an enlarged sectional view corresponding to line AA in FIG. 1;

FIG. 3 is a sectional view of a main part showing a second embodiment of the liquid cooling rotary machine according to the present invention.

FIG. 4 is a sectional view of a main part showing another embodiment of the liquid cooling rotary machine according to the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Outer rotor, 6 ... Bearing shaft, 8 ... Stator, 9 ... Liquid inlet path, 10 ... Discharge path, 11 ... Liquid inlet reservoir, 12 ... Flow hole, 13 ... Discharge reservoir, 15, 16 ... Shielding member, 17, 17A ... Pipe as air vent / drainage means, 19 ... Piping.

Continued on the front page (72) Inventor Hirofumi Ihara 3-1-1 Sachimachi, Hitachi-shi, Ibaraki Pref. Hitachi, Ltd. Hitachi Plant (72) Inventor Hiroaki Mita 3-1-1 Sachimachi, Hitachi-shi, Ibaraki Inside Hitachi, Ltd.Hitachi Plant No. 38 Inside the Railway Technical Research Institute (72) Inventor Keiichiro Kondo 2-38 Hikaricho 2-chome, Kokubunji-shi, Tokyo Inside the Railway Technical Research Institute

Claims (6)

[Claims] 1. An outer rotor, a bearing shaft rotatably supporting the outer rotor, a stator fixed to the bearing shaft and arranged inside the outer rotor, and cooling the stator by a coolant. A cooling device for introducing the cooling liquid from the outside to the stator, a discharging passage for discharging the cooling liquid passing through the stator to the outside, a liquid feeding passage and a discharging passage. And a flow path mechanism for flowing the coolant through the stator, and the flow path mechanism substantially fills the space downstream of the stator with the coolant flowing through the stator. A liquid-cooled rotating machine having a means for storing coolant in a state and guiding a coolant to a discharge path from a highest part in the space. 2. An outer rotor, a bearing shaft rotatably supporting the outer rotor, a stator fixed to the bearing shaft and arranged inside the outer rotor, and cooling the stator with a coolant. A cooling device for introducing the cooling liquid from the outside to the stator, a discharging passage for discharging the cooling liquid passing through the stator to the outside, a liquid feeding passage and a discharging passage. A circulation path mechanism connected between the stator and the circulation path mechanism for flowing the cooling liquid through the stator, and the circulation path mechanism is configured to collect the cooling liquid flowing through the stator at a downstream end face of the stator, and to collect the discharged liquid. A liquid-cooled rotary machine comprising: a cooling liquid discharge section configured to guide a cooling liquid in a discharge liquid sump section from a highest portion in the discharge liquid sump section to a discharge path. 3. An outer rotor, a bearing shaft rotatably supporting the outer rotor, a stator fixed to the bearing shaft and arranged inside the outer rotor, and cooling the stator with a coolant. A cooling device for introducing the cooling liquid from the outside to the stator, a discharging passage for discharging the cooling liquid passing through the stator to the outside, a liquid feeding passage and a discharging passage. And a flow path mechanism for flowing the coolant through the stator, and the flow path mechanism is configured to store the coolant from the inlet path on one axial end face side of the stator. A liquid reservoir for liquid, a flow hole through which the cooling liquid in the liquid reservoir for liquid flow flows through the stator, and a cooling liquid passing through the flow hole,
A drain reservoir for storage at the downstream end surface side, which is the other end surface in the axial direction of the stator, and a cooling fluid in the drain reservoir, from the highest portion in the drain reservoir to the discharge path. A liquid-cooled rotating machine comprising: an air vent / drainage means for guiding air. 4. A draining / draining means which is disposed in the drainage reservoir and has a pipe connected at one end to the drainage passage and the other end located at the highest position in the drainage reservoir. The liquid-cooled rotary machine according to claim 2 or 3, wherein: 5. The air venting / draining means comprises a connecting pipe having one end connected to the highest portion in the drainage reservoir and the other end connected to an externally-discharged discharge passage. The liquid-cooled rotary machine according to claim 2 or 3, wherein: 6. A connecting pipe having one end connected to the highest portion in the drainage reservoir and the other end connected to a drainage pipe connected to the outside, and a drainage / drainage means. 4. The liquid-cooled rotary machine according to claim 2, further comprising means for connecting a bottom part in the storage part and a discharge path.