JP4516684B2 - Cooling device for vehicle motor - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a vehicular motor cooling device that cools an electric motor for driving a vehicle with a coolant.
[0002]
[Prior art]
Conventionally, as this type of cooling device, for example, the one described in JP-A-10-259721 is known. This vehicle is of a hybrid type in which driving wheels are selectively driven by an engine and an electric motor. The cooling device for cooling the electric motor includes a radiator, a cooling liquid circulation passage connected between the radiator and the electric motor, and a reserve tank disposed at a highest portion of the cooling liquid circulation passage. And a coolant pump provided in the coolant circulation passage. In this cooling device, the coolant pump circulates through the coolant circulation passage by operating the coolant pump, and the electric motor is cooled by heat exchange between the coolant and the electric motor. In addition, the reserve tank is provided for the purpose of adjusting the pressure of the coolant in the coolant circulation passage, and this type of reserve tank generally has a function as a header tank that separates bubbles in the coolant. Is.
[0003]
[Problems to be solved by the invention]
According to the conventional cooling device described above, since many parts such as a radiator, an electric motor, a coolant pump, and a reserve tank have to be connected, the number of connecting parts such as pipes and joints for that purpose increases. As the number of assembling steps increases, the manufacturing cost increases, and the required space increases, so that the mounting property on the vehicle decreases.
[0004]
The present invention has been made to solve the above-described problems, and can reduce the number of parts and the number of assembling steps, thereby reducing the manufacturing cost, improving the vehicle mountability, and collecting air. It is an object of the present invention to provide a vehicular motor cooling device that can prevent the occurrence of the above and thereby ensure a sufficient cooling capacity.
[0005]
[Means for Solving the Problems]
In order to achieve this object, the invention according to claim 1 is a cooling device 1 for a motor for a vehicle that cools an electric motor 2 for driving a vehicle with a coolant 9, and the coolant 9 circulates. A coolant circulation passage 8; a jacket 6 provided on the surface side of the electric motor 2 so as to surround at least a part of the surface; and a jacket passage 10 forming a part of the coolant circulation passage 8; A header tank 7 for separating air bubbles from the coolant 9. The jacket passage 10 is provided integrally with the jacket passage 10 and connected to the coolant circulation passage 8 in a portion other than the jacket passage 10. Are an inlet passage portion (for example, the hose connection port 6c in the embodiment) that extends horizontally at a position lower than the header tank 7, and a bent portion (hose connection port) bent downward from the inlet passage portion. c, the inlet portion 10a) and the lower portion 10c extending downward from the bent portion, the coolant 9 is configured to flow from the inlet passage portion to the header tank 7 through the bent portion and the lower portion 10c, In addition to bypassing between the bent portion and the header tank 7, an air vent passage 11 having a smaller sectional area than the jacket passage 10 is further provided .
[0006]
According to this vehicle motor cooling device, the coolant circulates in the coolant circulation passage including the jacket passage, whereby the electric motor is cooled by the coolant and bubbles are separated from the coolant by the header tank. The Further, since the header tank and the jacket are integrated, the jacket passage can be directly connected to the header tank without using a pipe or a joint. As a result, the number of parts is reduced, and the number of assembling steps is reduced accordingly, so that the manufacturing cost can be reduced and the vehicle can be mounted with improved compactness. The jacket passage is configured such that the coolant flows from the inlet passage portion lower than the header tank to the header tank through the bent portion and the lower portion, and the bent portion is bypassed to the header tank via the air vent passage. . In such a jacket passage, air mixed in the coolant is likely to accumulate in the bent portion, and therefore such air can be released to the header tank by a short air vent passage connecting the bent portion and the header tank. it can. As a result, it is possible to prevent an air pool and a decrease in heat exchange efficiency between the electric motor and the coolant due to the air pool, and a sufficient cooling capacity can be ensured.
[0007]
The invention according to claim 2 is characterized in that, in the vehicle motor cooling device 1 according to claim 1, the bent portion is bent at an acute angle downward from the inlet passage portion .
[0008]
According to a third aspect of the present invention, in the vehicle motor cooling device 1 according to the first aspect, the jacket 6 and the header tank 7 are joined to each other via joint surfaces 6e and 7c, and the air vent passage 11 ( The groove 6k) is characterized in that it is formed in at least one of the joining surface 6e of the jacket 6 and the joining surface 7c of the header tank 7.
According to this vehicle motor cooling device, since the air vent passage is formed in the joint surface of the jacket and / or the header tank, the air vent passage that exhibits the above-described operation can be achieved by simply joining the two at the joint surface. Can be obtained. Further, since the air vent passage may be formed in advance on the joint surface where the air vent passage is opened, the air vent passage can be more easily formed as compared with the case of drilling a through hole.
[0009]
The invention according to claim 4 is the vehicle motor cooling device 1 according to claim 3 , wherein the joint surfaces 6e and 7c of the jacket 6 and the header tank 7 are formed flat, and the air vent passage 11 is formed as a flat joint. The groove 6k is formed in at least one of the joint surfaces 6e so as to extend along the surfaces 6e and 7c.
[0010]
The invention according to claim 5 is the vehicle motor cooling device 1 according to any one of claims 1 to 4, wherein the coolant circulation passage 8 is connected to the inverter 5, and the inverter 5 is connected to the inlet passage portion ( It is characterized by being arranged at a position lower than the hose connection port 6c).
[0011]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, a cooling device for a vehicle motor according to an embodiment of the present invention will be described with reference to the drawings. FIG. 1 shows a schematic configuration of the cooling device of the present embodiment. The cooling device 1 is applied to a vehicle (not shown), and the vehicle has an engine (not shown) as a front wheel and an electric motor (hereinafter referred to as “motor”) as a rear wheel (not shown). 2 is a so-called hybrid 4WD type. The motor 2 is an AC servo motor, and is electrically connected to a control device (not shown) and controlled by a drive signal from the control device being input via an inverter 5 described later.
[0012]
The cooling device 1 includes a radiator 3, a coolant pump 4, an inverter 5, a jacket 6, a header tank 7, and the like, and these are sequentially connected in series in the direction in which the coolant 9 flows through a hose 8 a. A coolant circulation passage 8 is formed. As the coolant 9 (see FIG. 2) circulates in the coolant circulation passage 8, the motor 2 is cooled.
[0013]
The radiator 3 cools the coolant 9 flowing inside the vehicle by exchanging heat with the traveling wind accompanying the traveling of the vehicle and by exchanging heat with air from an electric fan (not shown) while the vehicle is stopped. The radiator 3 is of a down flow type provided separately from a radiator (not shown) for cooling the engine, and the coolant 9 flows from the upper tank 3a to the lower tank 3c through the radiator core 3b.
[0014]
The upper tank 3a and the lower tank 3c are connected to the header tank 7 and the coolant pump 4 via hoses 8a and 8a, respectively. The coolant pump 4 is controlled by the control device and discharges the coolant 9 cooled by the radiator 3 to the inverter 5 side. Thus, the coolant 9 circulates in the coolant circulation passage 8 in the direction indicated by the thick arrow in the figure. The inverter 5 and the coolant pump 4 are arranged at the same height.
[0015]
Next, the jacket 6 and the header tank 7 will be described with reference to the cross-sectional view shown in FIG. In addition, in the same figure, the part shown by hatching shows the part with which the coolant 9 is satisfy | filled, and the thick arrow in a figure has shown the direction through which the coolant 9 flows. This also applies to FIGS. 3 to 7 described later.
[0016]
The motor 2 has a circular cross section and extends in the depth direction of the drawing, and a rotor, a stator, and the like are incorporated in the casing (none of them are shown). The jacket 6 is provided so as to surround the surface of the casing of the motor 2, and as shown in the figure, the inner casing 6a having an annular cross section and a slightly larger diameter and substantially the same cross sectional shape are used. And an outer casing 6b. Both casings 6a and 6b extend in the depth direction of the drawing with a space between each other, and both end portions thereof are watertightly closed by two lids (not shown). As a result, a jacket passage 10 is formed between the casings 6a and 6b and the two lids. The jacket passage 10 is C-shaped, and an upstream end thereof is connected to an inlet portion 10 a for introducing the coolant 9 into the jacket passage 10, and a downstream end portion thereof is connected to an outlet portion 10 b connected to the header tank 7. In addition, a space between the inlet portion 10a and the outlet portion 10b is a lower portion 10c having a lower height than these.
[0017]
On the other hand, the outer casing 6b is formed with a hose connection port 6c that communicates with the inlet portion 10a of the jacket passage 10, and this hose connection port 6c is cylindrical and protrudes outward from the outer casing 6b horizontally. Yes. The hose connection port 6c is connected to the downstream end of the hose 8a. The upstream end of the hose 8a is connected to the inverter 5 at a position lower than the hose connection port 6c. Furthermore, the portion from the hose connection port 6c to the inlet portion 10a of the jacket passage 10 has a passage shape that is bent at an acute angle downward from the horizontal toward the downstream side. As described above, the jacket passage 10 constitutes a part of the coolant circulation passage 8, whereby the motor 2 is cooled by the heat exchange action when the coolant 9 flows in the jacket passage 10. . In this case, since the jacket passage 10 has a C-shape that surrounds the motor 2 as described above, the passage length can be secured large, and the jacket passage 10 extends in the depth direction. A large contact area with the coolant 9 in 6a can be secured. As a result, heat exchange with the coolant 9 can be performed efficiently.
[0018]
An air vent passage 11 is formed between the inner casing 6a and the outer casing 6b. The air vent passage 11 has a cross-sectional area that is considerably smaller than that of the jacket passage 10, extends obliquely upward from the acutely curved passage-shaped portion, and is connected to bypass the outlet portion 10b. Yes. As a result, the bubbles in the coolant 9 flow into the header tank 7 through the air vent passage 11 together with a part of the coolant 9 without accumulating in the passage-shaped portion bent at an acute angle of the jacket passage 10. At that time, the amount of the coolant 9 flowing in the air vent passage 11 is considerably smaller than that on the jacket passage 10 side because the cross-sectional area of the air vent passage 11 is considerably smaller than that of the jacket passage 10.
[0019]
The upper surface of the outer casing 6b is a flat joining surface 6e. An annular ring groove 6f is formed on the joining surface 6e so as to surround the outlet portion 10b. An O-ring (not shown) is fitted in the annular groove 6f.
[0020]
On the other hand, the header tank 7 separates bubbles contained in the coolant 9 and replenishes the coolant 9 into the coolant circulation passage 8, and is therefore the highest in the coolant circulation passage 8. Placed in position. The header tank 7 includes a flat base portion 7a and a peripheral wall portion 7b that extends upward from the base portion 7a and is thinner than the base portion 7a. The bottom surface of the base portion 7a is a flat joint surface 7c. The header tank 7 has the joint surface 7c in close contact with the joint surface 6e of the outer casing 6b and sandwiches an O-ring between the jacket 6 and the header tank 7b. It is screwed to the jacket 6 in a watertight state. An inflow port 7d penetrating in the vertical direction is formed in the center of the base portion 7a and connected to the outlet portion 10b of the jacket passage 10.
[0021]
As described above, the header tank 7 is integrally attached to the upper side of the jacket 6 so that the inside thereof communicates with the jacket passage 10 and is watertight. A replenishing port is formed on the upper surface of the header tank 7 so as to protrude upward. A cap 7e with a relief valve (not shown) is attached to the replenishing port, and when the pressure in the coolant circulation passage 8 becomes larger than a predetermined pressure, the relief valve opens to cause the coolant circulation passage. The pressure in 8 is released to the outside and is kept below a predetermined pressure.
[0022]
A hose connection port 7f is provided on the peripheral wall 7b of the header tank 7 so as to protrude horizontally and in the same direction as the hose connection port 6c. One end of a hose 8a is connected to the hose connection port 7f, and the other end of the hose 8a is connected to the upper tank 3a of the radiator 3 at a lower position.
[0023]
Further, the coolant 9 is stored in the coolant circulation passage 8 so that the liquid level in the header tank 7 is lower than the replenishment port and higher than the hose connection port 7f. A coolant layer and an air layer are formed in the header tank 7, respectively. Bubbles in the cooling liquid 9 rise in the cooling liquid layer in the header tank 7, and are separated from this to move to the air layer. Thereby, the cooling fluid 9 is sent into the radiator 3 in a state where the bubbles are separated.
[0024]
As described above, according to the cooling device 1 of the present embodiment, the motor 2 is cooled as the coolant 9 circulates in the coolant circulation passage 8, and bubbles are separated from the coolant 9 by the header tank 7. Is done. Further, since the header tank 7 and the jacket 6 are integrated, the jacket passage 10 can be directly connected to the header tank 7 without using pipes or joints. As a result, the number of parts is reduced, and the number of assembling steps is reduced accordingly, so that the manufacturing cost can be reduced and the vehicle can be mounted with improved compactness.
[0025]
Further, the jacket passage 10 is formed in a C shape so as to surround the motor 2, and the coolant 9 flows from the inlet portion 10a of the jacket passage 10 to the outlet portion 10b through the low portion 10c. Largely secured. In addition, since the jacket passage 10 extends in the depth direction, a large contact area with the coolant 9 in the inner casing 6a can be secured. Thereby, heat exchange can be performed efficiently.
[0026]
Furthermore, since the portion from the hose connection port 6c to the inlet portion 10a of the jacket passage 10 is a downwardly bent passage shape, air mixed in the coolant 9 tends to accumulate in this portion. Since this portion is bypassed to the header tank 7 via the relatively short air vent passage 11, it is possible to release such air to the header tank 7 and to prevent air accumulation. Accordingly, it is possible to prevent the heat exchange efficiency between the motor 2 and the cooling from being lowered due to the air pool, and it is possible to ensure a sufficient cooling capacity.
[0027]
In the present embodiment, the inner casing 6a of the jacket 6 and the casing of the motor 2 are configured separately, but the inner casing 6a of the jacket 6 may also be configured to serve as the casing of the motor 2. In addition, the portion where the air vent passage 11 is provided is not limited to the portion from the hose connection port 6 c to the inlet portion 10 a of the jacket passage 10 in the embodiment, and air is likely to accumulate on the upstream side of the lower portion 10 c of the jacket passage 10. Any site may be used.
[0028]
Next, a modified example of the cooling device 1 will be described with reference to FIGS. 3 to 7 respectively show different modifications. These cooling devices 1 differ from the cooling device 1 of the above-described embodiment only in the configuration of the jacket 6 and the header tank 7, and in any case, the same effects as the cooling device 1 of the embodiment can be obtained. it can. Hereinafter, each modification will be described focusing on differences from the embodiment.
[0029]
First, the cooling device 1 shown in FIG. 3 is different from the cooling device 1 of the embodiment in the joining portion of the jacket 6 and the header tank 7. That is, the header tank 7 is formed with a cylindrical protruding portion 7g protruding from the center of the joint surface 7c of the base portion 7a, and the inside of the protruding portion 7g is an inflow port 7d. An annular groove 7h extending in the circumferential direction is formed on the outer peripheral surface of the protruding portion 7g, and an O-ring (not shown) is fitted into the annular groove 7h. On the other hand, an upper outlet portion of the outer casing 6b of the jacket 6 is formed with an outlet 10d that opens upward, continues to the outlet portion 10b of the jacket passage 10, and has a slightly larger diameter than the protruding portion 7g. The header tank 7 is screwed to the jacket 6 in a watertight state in which the protruding portion 7g is fitted to the outlet 10d and an O-ring is sandwiched between the header 10 and the wall surface of the outlet 10d. Further, the inside of the header tank 7 and the jacket passage 10 are communicated with each other via an inflow port 7d of the protruding portion 7g. As described above, the header tank 7 is integrally attached to the jacket 6 in a watertight state.
[0030]
The cooling device 1 shown in FIG. 4 is also different from the cooling device 1 of the embodiment in the joint portion between the jacket 6 and the header tank 7. That is, compared with the modified example of FIG. 3, the inlet 7d of the header tank 7 is widened to the same diameter as the inner diameter of the peripheral wall 7b, and the outlet 10b of the jacket passage 10 has the same diameter correspondingly. Has been widened. Therefore, according to this cooling device 1, compared with the cooling device 1 of the embodiment, the volume of the header tank 7 can be increased, and thereby the ability to separate bubbles from the coolant 9 can be increased. For the same reason, the coolant 9 gradually flows into the header tank 7 as compared with the case where the coolant 9 is throttled by the small inlet 7d as in the cooling device 1 of the embodiment, so that the bubble separation capability of the header tank 7 is further increased. Can be increased. Further, the outlet portion 10b of the jacket passage 10 is widened, whereas the air vent passage 11 is shorter, so that the air can be vented more reliably.
[0031]
In the cooling device 1 shown in FIG. 5, the header tank 7 of the cooling device 1 of FIG. 4 is screwed to the jacket 6 whereas the header tank 7 is integrally fixed to the jacket 6 by welding. Are different. That is, the header tank 7 and the jacket 6 are made of the same metal (for example, aluminum alloy). The header tank is omitted from the base portion 7a and opens downward, and the joining surface of the jacket 6 is also provided. It is fixed to 6e by welding. Therefore, this cooling device 1 can also obtain the same effect as the cooling device 1 of FIG.
[0032]
In the cooling device 1 shown in FIG. 6, the joint surface 7 c of the header tank 7 and the joint surface 6 e of the jacket 6 are formed obliquely, and instead of the hose connection port 6 c provided in the jacket 6 of the embodiment, a hose is used. A connection port 7 j is provided at the lower end of the header tank 7. A hose 8 a is connected to the hose connection port 7 j and the lower tank 3 c of the radiator 3. On the other hand, an inlet portion 10a and an outlet portion 10b of the jacket passage 10 are opened in a round hole shape and a square hole shape, respectively, on the joint surface 6e of the jacket 6, and the inlet portion 10a is orthogonal to the joint surface 6e. And is connected to the hose connection port 7j. Further, the outlet portion 10 b is connected to the header tank 7. Further, a groove 6k that connects the inlet portion 10a and the outlet portion 10b is formed in the joint surface 6e, and the air vent passage 11 is configured by the groove 6k and the joint surface 7c of the header tank 7. Yes.
[0033]
Therefore, according to this cooling device 1, since the groove 6k constituting the air vent passage 11 is formed in the joining surface 6e of the jacket 6, only the header tank 7 and the jacket 6 are joined by the joining surfaces 7c and 6e. Thus, it is possible to obtain the air vent passage 11 having the above-described effects. In addition, since the groove 6k may be formed in advance on the joint surface 6e, the air vent passage 11 can be more easily formed as compared to the case of drilling a through hole. The groove 6k constituting the air vent passage 11 may be formed on the joint surface 7c of the header tank 7, or may be formed on both the joint surfaces 7c and 6e.
[0034]
In the cooling device 1 shown in FIG. 7, unlike the cooling device 1 shown in FIG. 6, the joining surface 7c of the header tank 7 and the joining surface 6e of the jacket 6 are formed horizontally. In addition, the inlet portion 10a extends in the vertical direction, and the air vent passage 11 is formed in a passage wall 7k configured as a part of the header tank 7 in the vicinity of the connection portion between the inlet portion 10a and the hose connection port 7j. Is formed. Since the passage wall 7k is thinner than the casings 6a and 6b of the jacket 6, the air vent passage 11 can be easily formed by, for example, drilling.
[0035]
【The invention's effect】
As described above, according to the vehicle motor cooling device of the present invention, since the header tank and the jacket are integrated, the jacket passage can be directly connected to the header tank without using a pipe or a joint. it can. As a result, the number of parts is reduced, and the number of assembling steps is reduced accordingly, so that the manufacturing cost can be reduced and the vehicle can be mounted with improved compactness.
[0036]
The jacket passage is configured such that the coolant flows from the inlet portion lower than the header tank to the header tank through the lower portion, and the upstream portion of the lower portion is connected to the header tank via the air vent passage. Bypassed. In such a jacket passage, the air mixed in the coolant is likely to accumulate in the upstream portion of the lower portion including the inlet portion, so that such air is a short air connecting the inlet portion and the header tank. The removal passage allows escape to the header tank. As a result, it is possible to prevent an air pool and a decrease in heat exchange efficiency between the electric motor and the coolant due to the air pool, and a sufficient cooling capacity can be ensured.
[0037]
Further, since the air vent passage is formed on the joint surface of the jacket and / or the header tank, the air vent passage having the above-described effect can be obtained only by joining the two at the joint surface. Further, since the air vent passage may be formed in advance on the joint surface where the air vent passage is opened, the air vent passage can be more easily formed as compared with the case of drilling a through hole.
[Brief description of the drawings]
FIG. 1 is an explanatory diagram showing a schematic configuration of a cooling device for a vehicle motor according to an embodiment of the present invention.
FIG. 2 is a cross-sectional view showing a configuration of a jacket and a header tank of a cooling device.
FIG. 3 is a cross-sectional view showing a configuration of a modified example of the cooling device.
FIG. 4 is a cross-sectional view showing a configuration of another modified example of the cooling device.
FIG. 5 is a cross-sectional view showing a configuration of still another modification of the cooling device.
6A is a cross-sectional view showing a configuration of a modified example of the cooling device different from the modified examples of FIGS. 3 to 5 and FIG.
FIG. 7 is a cross-sectional view showing a configuration of a modified example of the cooling device different from the modified examples of FIGS.
[Explanation of symbols]
1 Cooling device 2 Electric motor
5 Inverter 6 Jacket
6c hose connection port (inlet passage part, bent part)
6e Joint surface 6k Groove (Air vent passage)
7 Header tank 7c Joint surface 8 Coolant circulation passage 9 Coolant 10 Jacket passage 10a Inlet part (bent part)
10c Low part 11 Air vent passage

Claims (5)

A cooling device for a vehicle motor that cools an electric motor for driving a vehicle with a coolant,
A coolant circulation path through which the coolant circulates;
A jacket provided on the surface side of the electric motor so as to surround at least a part of the surface, and a jacket passage forming a part of the coolant circulation passage is formed;
A header tank provided integrally on the upper side of the jacket, connected to the jacket passage and the coolant circulation passage in a portion other than the jacket passage, and for separating bubbles from the coolant;
Equipped with a,
The jacket passage has an inlet passage portion that extends horizontally at a position lower than the header tank, a bent portion that is bent downward from the inlet passage portion, and a low portion that extends downward from the bent portion, and The liquid is configured to flow from the inlet passage portion to the header tank via the bent portion and the lower portion,
The vehicle motor cooling device further includes an air vent passage that bypasses between the bent portion and the header tank and has a smaller cross-sectional area than the jacket passage . The cooling device for a vehicle motor according to claim 1, wherein the bent portion is bent at an acute angle downward from the inlet passage portion . The jacket and the header tank are joined to each other via a joining surface, and the air vent passage is formed on at least one joining surface of the joining surface of the jacket and the joining surface of the header tank. The vehicular motor cooling device according to claim 1 . The joint surfaces of the jacket and the header tank are formed flat, and the air vent passage is constituted by a groove formed in the at least one joint surface so as to extend along the flat joint surface. The vehicle motor cooling device according to claim 3. The coolant circulation passage is connected to an inverter;
5. The vehicle motor cooling device according to claim 1, wherein the inverter is disposed at a position lower than the inlet passage portion.

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