JP7113808B2 - Oil passage structure - Google Patents

Description

The present invention relates to a cooling structure for cooling an electric motor provided in a vehicle.

In recent years, two electric motors, a first electric motor (MG1) for power generation and a second electric motor (MG2) for driving, are provided. A hybrid vehicle (series hybrid vehicle) driven by two electric motors is provided. As a device for cooling the electric motor of such a hybrid vehicle, Patent Document 1 below discloses a cooling device for cooling the electric motor.

JP 2017-61226 A

By the way, in an oil passage structure provided in a transaxle or the like, it is necessary to monitor the temperature of the oil, and a temperature sensor is sometimes provided. Also, the temperature sensor is provided so as to be immersed in the oil.

Here, if the oil at the position where the temperature sensor is provided is interrupted and the temperature sensor comes into contact with air (detects air), it may cause a detection error of the temperature sensor. Therefore, it is desirable that the temperature sensor be provided in a portion where oil is always accumulated. In particular, in the case of a series hybrid vehicle in which the oil pump operates in conjunction with the driving of the engine, it is assumed that the vehicle will run with the engine stopped (EV running). Since the operation of the oil pump also stops when the engine is stopped during EV driving, it is assumed that the oil in the oil passage will flow down to the oil reservoir, etc., and the oil will not be supplied to the position where the temperature sensor is installed. be.

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide an oil passage structure for an electric motor that can suppress errors in the temperature sensor.

An oil passage structure of the present invention provided to solve the above-described problems has an oil passage serving as an oil passage for cooling an electric motor, and a temperature sensor for detecting the temperature in the oil passage. The oil passage has a first oil passage provided to face the axial center of the electric motor, and a second oil passage branched from the first oil passage and formed in a dead-end manner, and the temperature sensor is arranged in the second oil passage below a branch position with the first oil passage.

According to the oil passage structure of the present invention, even when the oil pressure is lost when the oil pump is stopped (during EV running), the second oil passage can be always filled with oil. As a result, the oil passage structure of the present invention can suppress the occurrence of problems such as the temperature sensor not being able to detect the temperature of the oil.

In the oil passage structure of the present invention, the portion where the first oil passage and the second oil passage diverge, and the temperature sensor may be positioned axially laterally of the electric motor.

According to the above configuration, it is possible to detect the temperature of the oil immediately upstream of the electric motor, which particularly requires temperature control, and improve the controllability of the electric motor.

The oil passage structure of the present invention includes a case body that houses the electric motor, and an intervening member that is arranged to be interposed between the electric motor and the case body, and the temperature sensor is located in the case body. It is preferable that the case body is inserted into the second oil passage from the inside, and that the intervening member restricts the movement of the case body toward the inside.

According to the above configuration, the intervening member restricts the movement of the temperature sensor and functions as a retainer, eliminating the need for a member for fixing the temperature sensor, thus reducing costs.

An oil passage structure of the present invention is an oil passage structure for an electric motor including an electric motor and a case body that houses the electric motor, the oil passage serving as a flow path for oil for cooling the electric motor, a temperature sensor, A part of the oil passage is a second oil passage having a cul-de-sac shape, the temperature sensor is arranged in the second oil passage, and the second oil passage is an oil It is characterized by being formed on the lower side in the flow direction.

According to the oil passage structure of the present invention, it is possible to maintain a state in which the temperature sensor is always in contact with the oil, assuming that the second oil passage is always filled with oil. In other words, the temperature sensor is always immersed in oil, and the concern that the temperature sensor will detect air can be eliminated. As a result, the oil passage structure of the present invention can reduce temperature detection errors and accurately detect the temperature of the oil.

Here, when the potential difference between the electric motor and the case body becomes high, an intervening member such as a cover body is arranged in the portion (mounting portion) of the case body where the electric motor is attached (mounting portion) to suppress electrolytic corrosion. may occur. As the intervening member, for example, an alumite-treated member (such as an electrolytic corrosion cover) or an insulator (insulating plate) can be considered. Further, when the temperature sensor is provided in the oil passage formed in the case body, the temperature sensor is attached to the case body using a fastening member or the like.

Here, the inventors of the present invention have studied a configuration for reducing the number of parts, and found that a second oil passage is provided in the portion (mounting portion) of the case body to which the electric motor is attached, and the temperature sensor is placed between the intervening member and the case. It has been found that the number of parts can be reduced by arranging it between the body and the body. In other words, the inventors of the present invention make existing parts (such as a cover body) function as a retainer for the temperature sensor, thereby reducing the number of fastening members and the like for fixing the temperature sensor. I have come to an understanding.

In the oil passage structure of the present invention provided based on the above findings, the second oil passage is formed in the case body, and an intervening member is provided to separate the electric motor and the case body. The intervening member is attached to the case body and arranged to restrict movement of the temperature sensor in a direction away from the second oil passage. .

According to the above-described configuration, an existing part (intervening member) can be made to function as a retainer for the temperature sensor, and the number of fastening members and the like for fixing the temperature sensor can be reduced.

Further, in the oil passage structure of the present invention, the second oil passage is formed in the vicinity of a turning corner position in the route of the oil passage, and the turning corner position is a portion where oil flows down from above. should be

According to the above configuration, it is possible to allow fresh oil to flow into the second oil passage more efficiently.

ADVANTAGE OF THE INVENTION According to this invention, the oil-path structure of the electric motor which can suppress the error of a temperature sensor can be provided.

1 is a schematic diagram showing a transaxle having an oil passage structure according to an embodiment of the present invention; FIG. FIG. 2 is a side view showing a gear chamber of the transaxle of FIG. 1; FIG. 2 is a side view of the transaxle of FIG. 1 on the front side; FIG. 2 is a left side view of the transaxle of FIG. 1; FIG. 2 is an exploded perspective view showing the configuration of the gear chamber side of the transaxle of FIG. 1; FIG. 2 is a diagram showing a third supply passage and a dead end of the transaxle of FIG. 1; FIG. 2 is a sectional view showing a rotor shaft and a nozzle portion of the transaxle of FIG. 1; FIG. 2 is a perspective view showing the entire oil flow in the oil passage structure of FIG. 1; FIG. 2 is a conceptual diagram in a side view showing the oil passage structure of FIG. 1; FIG. 2 is a plan view showing an upstream oil passage and a downstream oil passage of the oil passage structure of FIG. 1; (a) is a side view showing the gear chamber side of the transaxle of FIG. 1, (b) is a side view of an oil pump body, and (c) is a perspective view of the oil pump body.

Hereinafter, an oil passage structure 10 according to an embodiment of the present invention will be described with reference to the drawings.

In the following description, prior to details of the oil passage structure 10, the overall configuration of the transaxle 1 including the oil passage structure 10 will be described. The oil passage structure 10 is a structure for cooling the first electric motor 20 (MG1) and the second electric motor 30 (MG2) in the transaxle 1 .

It should be noted that the oil passage structure of the present invention is not limited to that provided in the transaxle of a series-type hybrid vehicle, and may be applied to a parallel-type hybrid vehicle, an AT vehicle, an electric vehicle, etc. as a structure for cooling a vehicle motor (electric motor). It can be preferably adopted. Moreover, the oil passage structure of the present invention is not limited to that provided in a transaxle, and can be employed for cooling an electric motor.

A transaxle 1 is provided in a vehicle V shown in FIG. The vehicle V is provided with an engine (not shown) and a battery (not shown). The vehicle V uses the engine as a power source to drive a first electric motor 20, which will be described later, and the first electric motor 20 drives a second electric motor 30, which will be described later. is used as a power source to drive the second electric motor 30 to run (EV running), which is a so-called series hybrid vehicle.

In the following description, the vertical direction when the transaxle 1 is mounted on the vehicle V is simply referred to as the "vertical direction H". In addition, in the vertical direction H, the upward direction is simply described as "upper Up", and the downward direction is simply described as "downward Lw".

Further, in the following description, when the transaxle 1 is mounted on the vehicle V, the front-rear direction of the vehicle V is simply referred to as "the front-rear direction X". Further, in the front-rear direction X, the front is simply described as "front Fr", and the rear is simply described as "rear Rr".

Further, in the following description, when the transaxle 1 is mounted on the vehicle V, the width direction of the vehicle V is simply referred to as the "width direction W".

As shown in FIG. 1 , the transaxle 1 includes a transaxle housing 40 , a first electric motor 20 (electric motor), a second electric motor 30 (electric motor), and a differential mechanism 32 .

The transaxle 1 also includes an oil pump 60, a partition plate 61 (partition), an oil pump body 62, a relief valve 63 (pressure regulator), a strainer 64, an oil cooler 70, an electrolytic corrosion cover 80, an insulating plate 84, A temperature sensor 86 and a cooling pipe 90 are provided.

The first electric motor 20 (MG1) consists of a motor generator. A generator controller including an inverter and the like is connected to the first electric motor 20 . Although illustration is omitted, the generator controller is mounted on the upper portion of the transaxle 1 . The AC power output from the first electric motor 20 is converted into DC power by the generator controller, and the DC power is supplied to the battery to charge the battery. The first electric motor 20 is driven by the rotational power transmitted by the drive of the engine (not shown).

The second electric motor 30 (MG2) consists of a motor generator. A motor controller including an inverter and the like is connected to the second electric motor 30 . Although illustration is omitted, the generator controller is mounted on the upper portion of the transaxle 1 . A battery is connected to the motor controller. The DC power output from the battery is supplied to the motor controller, the DC power is converted into AC power by the motor controller, and the AC power is supplied to the second electric motor 30, thereby driving the second electric motor 30. .

In the following description, the first electric motor 20 (MG1) and the second electric motor 30 (MG2) may be generically referred to simply as "electric motor 18".

The first electric motor 20 and the second electric motor 30 each have a stator and a rotor having a rotor shaft.

As shown in FIG. 7, the rotor shaft 24 of the first electric motor 20 is formed with a hollow portion 24a, shaft communication holes 24b, and protrusions 24c. Oil is supplied to the hollow portion 24a from a nozzle portion 82, which will be described later, and the oil in the hollow portion 24a flows out of the rotor shaft 24 from the shaft communication hole 24b due to the centrifugal force caused by the rotation of the rotor shaft 24. The flow of oil guided by the rotor shaft 24 will be described in detail later.

The differential mechanism 32 is configured to allow a differential between a pair of left and right drive shafts (not shown) that drive the left and right drive wheels, and to transmit rotational power to the pair of left and right drive shafts. . As shown in FIG. 1, the differential mechanism 32 includes a plurality of gears including a differential ring gear 32a and a differential gear 32b.

The power of the second electric motor 30 is transmitted to the differential ring gear 32 a of the differential mechanism 32 via a plurality of gears, and then transmitted from the differential mechanism 32 to the driving wheels 2 . As a result, the drive wheels 2 rotate and the vehicle V runs.

The transaxle housing 40 (case body) is a container for housing the first electric motor 20, the second electric motor 30, and the like. As shown in FIG. 1, the transaxle housing 40 (case body) forms one container with three constituent members. More specifically, the transaxle housing 40 is composed of a first component 40a, a second component 40b, and a third component 40c.

As shown in FIG. 1 , the first structure 40 a forms an intermediate portion in the width direction W of the transaxle housing 40 . As shown in FIG. 1 , a partition wall 43 is formed in the first structure 40 a , and the partition wall 43 separates a space that serves as the motor chamber 41 and a space that serves as the gear chamber 42 . The second structure 40b is attached to the motor chamber 41 side of the first structure 40a. Furthermore, the third structure 40c is attached to the gear chamber 42 side.

In the following description, the first structural body 40a, the second structural body 40b, and the third structural body 40c may be collectively referred to as the transaxle housing 40 for explanation.

As described above, the internal space of the transaxle housing 40 is partitioned into the motor chamber 41 and the gear chamber 42 by the partition wall 43 . As shown in FIG. 1 , the motor chamber 41 accommodates the first electric motor 20 and the second electric motor 30 . The gear chamber 42 accommodates the differential mechanism 32 .

In addition, the transaxle housing 40 contains oil, which is pumped by an oil pump 60 (to be described later) to cool the first electric motor 20 and the second electric motor 30 .

As described above, the transaxle housing 40 in the oil passage structure 10 of the present embodiment is configured by three constituent members, but the case body in the oil passage structure of the present invention is The shape is not limited, and it may be formed by two or four or more constituents.

A plurality of through holes and recesses are formed in the transaxle housing 40 . At least part of the through-holes and recesses formed in the transaxle housing 40 constitute an internal oil passage 100a of the oil passage 100, which will be described later (see FIG. 10). Details of the oil passage 100 will be described later.

FIG. 2 is a side view showing the gear chamber 42 of the transaxle 1. FIG. As shown in FIG. 2, an oil reservoir 50 is provided at the bottom of the transaxle housing 40 on the gear chamber 42 side. The oil storage portion 50 is a portion in which oil circulating in an oil passage 100, which will be described later, is stored. A strainer 64 is arranged in the oil reservoir 50 . As shown in FIGS. 9 and 8, the oil pumped from the oil reservoir 50 to the oil pump 60 via the strainer 64 is used for cooling the electric motors 18 via the oil passage 100. As shown in FIGS. Also, the oil used for cooling the electric motor 18 and the like returns to the oil reservoir 50 again through the through-hole communicating with the gear chamber 42 from the motor chamber 41 .

As shown in FIG. 5 , the transaxle housing 40 is provided with a plurality of recesses 45 . As shown in FIG. 5, the transaxle housing 40 (first component 40a) includes a first concave portion 45a that guides the oil sucked up from the strainer 64, and a pump accommodating chamber 52 that accommodates the oil pump 60. There are two recesses 45b and a third recess 45c forming a release chamber 54 for releasing oil by operating a relief valve 63, which will be described later.

The first recess 45 a is closed by the oil pump body 62 to form the guide chamber 51 . The second recess 45b and the third recess 45c are closed by the partition plate 61 to form a space (pump housing chamber 52, discharge chamber 54, etc.) that serves as an oil passage in the oil passage structure 10. As shown in FIG. The guide chamber 51, the pump accommodation chamber 52, and the discharge chamber 54 will be described in detail later.

Further, the transaxle housing 40 is provided with a first passage 54a, a second passage 54c, and a discharge port 54b. The first passage 54 a communicates with the oil reservoir 50 . The second passageway 54c also forms a discharge chamber 54 with a constant volume. The outlet 54 b is provided in the second passage 54 c and communicates with the motor chamber 41 .

The oil pump 60 is for pumping the oil in the oil reservoir 50 . As shown in FIG. 5 , the oil pump 60 is housed in a pump housing chamber 52 formed in the partition wall 43 of the transaxle housing 40 . In the oil pump 60, a pump gear 60a rotates as an engine (not shown) is driven to pump oil. Further, as described above, the first electric motor 20 is driven by the rotational power transmitted by the driving of the engine, and the oil pump 60 operates in conjunction with the first electric motor 20 by driving the engine.

The oil pump body 62 is attached to the partition wall 43 (on the gear chamber 42 side) of the transaxle housing 40 with a member such as a bolt. More specifically, the oil pump body 62 closes the first recess 45a, the second recess 45b, and the third recess 45c formed in the partition wall 43 of the transaxle housing 40 (first component 40a). attached to the transaxle housing 40. A partition plate 61 is interposed between the oil pump body 62 and the transaxle housing 40 .

A strainer 64 is connected to the oil pump body 62 . Furthermore, as shown in FIGS. 11(b) and 11(c), the oil pump body 62 is formed with a fourth recess 62a. The fourth recessed portion 62a is a "substantially doglegged" recess formed on the surface of the oil pump body 62 facing the partition wall 43, and forms the pressure adjustment chamber 53 when the partition plate 61 is attached. Together, it is configured as an oil passage 100 that serves as an oil flow passage.

The partition plate 61 is arranged so as to be interposed between the transaxle housing 40 (first component 40 a ) and the oil pump body 62 . In other words, the partition plate 61 separates the plurality of recesses 45 (first recesses 45a, etc.) formed in the transaxle housing 40 and the recesses (fourth recesses 62a) formed in the oil pump body 62. arranged to separate.

A plurality of holes are formed in the partition plate 61 . Specifically, the partition plate 61 is formed with a first hole 61a, a second hole 61b, a third hole 61c, and a fourth hole 61d. In the following description, the state in which the partition plate 61 and the oil pump body 62 are attached to the transaxle housing 40 may be simply referred to as an "assembled state".

The first hole 61a is formed to extend in the vertical direction H, and constitutes a guide chamber 51 that guides the oil pumped up from the strainer 64 to the pump housing chamber 52 in the assembled state.

The second hole 61b has a substantially fan-like shape, and serves as an oil communication passage from the pump accommodating chamber 52 to the pressure regulating chamber 53 in the assembled state.

The third hole 61c is a substantially circular hole. The third hole 61c serves as an oil communication passage from the pressure adjustment chamber 53 toward an internal oil passage 100a, which will be described later, in the assembled state.

The fourth hole 61d is a substantially circular hole. The fourth hole 61d serves as an oil communication path (release hole 55) from the pressure adjustment chamber 53 to the release chamber 54 in the assembled state. The fourth hole 61d is closed by a relief valve 63, which will be described later. Further, when the relief valve 63 is operated according to the pressure of the oil passage 100, the fourth hole 61d (discharge hole 55) changes from the closed state to the open state, and the oil passage is opened.

The relief valve 63 is provided to enable closing and opening of the fourth hole 61d (discharge hole 55). As shown in FIG. 5, the relief valve 63 includes a cap portion 63a and a biasing member 63b. The relief valve 63 is arranged in the discharge chamber 54 with the cap portion 63a biased toward the fourth hole 61d by the biasing member 63b.

As shown in FIG. 7 , the electrolytic corrosion cover 80 (intervening member) is provided so as to be interposed between the rotor shaft 24 and the transaxle housing 40 . A bearing 88 that supports the rotor shaft 24 is attached to the electrolytic corrosion cover 80 . The electrolytic corrosion cover 80 and the bearing 88 are subjected to an alumite treatment to suppress corrosion (electrical corrosion) due to the potential difference between the transaxle housing 40 and the rotor shaft 24 .

The electrolytic corrosion cover 80 is provided with a nozzle portion 82 . As shown in FIG. 7, the nozzle portion 82 is arranged in the hollow portion 24a of the rotor shaft 24 and is for supplying oil to the hollow portion 24a. The nozzle portion 82 is formed with a discharge port 82a serving as an oil outlet. The electrolytic corrosion cover 80 of this embodiment is formed by casting.

The insulating plate 84 (intervening member, plate member) shown in FIG. 7 is a plate-shaped member to which an insulating treatment has been applied. The insulating plate 84 is provided so as to be interposed between the electrolytic corrosion cover 80 and the transaxle housing 40 . A through hole 84 a (orifice) is formed in the insulating plate 84 . The through hole 84a is provided so as to be offset with respect to the discharge port 82a. As a result, it is possible to prevent the oil from flowing out of the through hole 84a from being supplied directly to the tip of the rotor shaft 24 through the discharge port 82a of the nozzle portion 82 . In other words, oil can be reliably supplied to the inner peripheral surface of the rotor shaft 24 . Further, the through hole 84a has a distance of L2 from the axial center C of the rotor shaft 24 (the axial center of the nozzle portion 82) when the insulating plate 84 is assembled to the transaxle housing 40 (the second component 40b). It is formed to be offset by minutes.

A temperature sensor 86 is provided to detect the temperature of the oil. The temperature sensor 86 is attached to a dead end 47 (second oil passage), which will be described later. More specifically, as shown in FIGS. 6 and 7, the temperature sensor 86 has its tip inserted into the cul-de-sac 47 and its other end facing the insulating plate 84 . In the transaxle 1 , the insulating plate 84 and the electrolytic corrosion cover 80 function as retainers for the temperature sensor 86 . The details of these arrangements will be described later.

The cooling pipe 90 is a pipe member for jetting oil to cool the electric motor 18 . The cooling pipe 90 is provided in the motor chamber 41 inside the transaxle housing 40 . As shown in FIG. 9, the cooling pipes 90 are provided above the first electric motor 20 and above the second electric motor 30, respectively. The cooling pipe 90 is provided with an oil ejection port 93 , and the oil supplied to the cooling pipe 90 is ejected from the oil ejection port 93 toward each electric motor 18 in a shower shape to cool each electric motor 18 .

In the following description, the cooling pipe 90 for cooling the first electric motor 20 is described as the first cooling pipe 91, and the cooling pipe 90 for cooling the second electric motor 30 is described as the second cooling pipe 92. and explain.

<About the oil passage of the oil passage structure>
Next, the oil passage 100 in the oil passage structure 10 will be described. FIG. 8 is a conceptual diagram showing the overall configuration of the oil passage 100. As shown in FIG. The oil passage 100 is provided as an oil passage for cooling each electric motor 18 .

The oil passage 100 of the oil passage structure 10 of this embodiment includes an internal oil passage 100a and an external oil passage 100b. The internal oil passage 100a is a through hole formed in the transaxle housing 40, or a recess formed in the transaxle housing 40 and closed by another member to form an oil flow path. Further, the external oil passage 100b forms an oil flow path using a member (for example, a pipe member) different from the transaxle housing 40. As shown in FIG.

As shown in FIG. 9 , in the oil passage structure 10 , the oil in the oil reservoir 50 is pumped upward by the oil pump 60 via the strainer 64 . As shown in FIGS. 8 and 9, the oil pumped by the oil pump 60 passes through a pressure regulating chamber 53 formed in the oil pump body 62 and passes through an internal pressure chamber 53 formed to bypass the outside of the first electric motor 20. It is guided by the oil passage 100 a and reaches the oil cooler 70 .

As shown in FIG. 8, the oil cooler 70 is provided so as to connect the oil passage 100 on the lower Lw side and the oil passage 100 on the upper Up side. From another point of view, the oil passage 100 is connected to the oil passage 100 on the lower Lw side and the oil passage 100 on the upper Up side via an oil cooler 70, and the oil cooler 70 directs the oil upward Up. It forms a flow path for conveying.

In the following description, the oil passage 100 upstream of the oil cooler 70 (oil passage 100 on the lower Lw side) is simply referred to as the "lower oil passage 101", and the oil passage downstream of the oil cooler 70. 100 (oil passage 100 on the upper Up side) may be described simply as "upper side oil passage 102".

As shown in FIG. 8, the oil flowing out from the oil cooler 70 is branched and distributed to both sides of the electric motor 18 in the axial direction G, and is distributed so as to branch further. Specifically, the oil that has flowed out of the oil cooler 70 flows through a first supply passage 111 directed upwardly of the first electric motor 20, a second supply passage 112 directed upwardly of the second electric motor 30, and a first It is distributed in three paths, with the third supply path 113 towards the rotor shaft 24 of the electric motor 20 .

Thus, in the oil passage structure 10, the oil pump 60 pumps the oil toward the oil cooler 70, and the oil (cooled oil) flowing out from the oil cooler 70 is distributed toward a plurality of locations.

The first supply passage 111 is connected to the first cooling pipe 91 and serves as an oil supply passage for cooling the first electric motor 20 . The second supply path 112 is connected to the second cooling pipe 92 and serves as an oil supply path for cooling the second electric motor 30 .

As shown in FIGS. 4 and 6, the third supply path 113 is a path that slopes from upward Up to downward Lw on the side of the transaxle housing 40 (the side on the side of the motor chamber 41). , forming a curved path along the axial direction G of the rotor shaft 24 at the mounting portion 46 of the first electric motor 20 .

As shown in FIG. 7 , the oil that has passed through the third supply passage 113 is supplied to the inside (hollow portion 24 a ) of the rotor shaft 24 through the nozzle portion 82 , and through the shaft communication hole 24 b of the rotor shaft 24 to the first electric motor 20 . cooled from the inside.

As described above, in the oil passage structure 10 of the present embodiment, the oil cooled by one oil cooler 70 is distributed between the path for cooling the electric motors 18 from above and the path for cooling the first electric motor 20 from the inside. distributed.

Next, details of the oil passage structure 10 provided in the transaxle 1 will be described. The oil passage structure 10 includes an oil passage 100, an oil pump 60, an oil cooler 70, an oil pump body 62, a partition plate 61, a nozzle portion 82, an insulating plate 84, a rotor shaft 24, a temperature sensor 86, and the like.

<1. Regarding the relationship between the arrangement of the oil cooler and the position of the internal oil passage>
In the oil passage structure 10 of the present embodiment, while the oil cooler 70 is provided outside the transaxle housing 40, the number of parts such as the pipe material for configuring the external oil passage 100b for connecting to the oil cooler 70 is increased. It is restrained. Further, in the oil passage structure 10, by adjusting the positions of the internal oil passage 100a for guiding oil to the oil cooler 70 and the internal oil passage 100a for distributing the oil from the oil cooler 70 to each supply passage, the transaxle housing The size reduction of the transaxle 1 is realized by suppressing an increase in the thickness of the transaxle 40 . A detailed description will be given below.

As described above, in oil passage structure 10 , oil cooler 70 is provided outside transaxle housing 40 . Further, as shown in FIG. 8, in the oil passage structure 10, the oil cooler 70 also serves as part of the oil passage 100 extending upward. In other words, in the oil passage structure 10, the oil cooler 70 is provided on a path along which the oil is transported upward in the vertical direction H when the transaxle housing 40 is loaded on the vehicle V. there is

According to the oil passage structure 10, the oil cooler 70 can be combined with the oil passage 100 for conveying oil from the lower side Lw to the upper side Up, and a member such as a pipe arranged outside the transaxle housing 40 ( (members constituting the external oil passage 100b) can be reduced. Further, according to the oil passage structure 10, the transaxle housing 40 can be made compact.

As described above, in the oil passage structure 10, the oil cooler 70 has a substantially rectangular appearance. In the oil passage structure 10, an oil inlet 70a and an oil outlet 70b provided in the oil cooler 70 are provided at diagonal positions of the oil cooler 70 (see FIGS. 3 and 8).

More specifically, the oil inlet 70a and the oil outlet 70b of the oil cooler 70 are provided in the vicinity of corners in the vertical direction H and at diagonal positions.

<2. Oil passage pressure adjustment function and motor (stator) cooling >
Next, the function of adjusting the pressure of the oil passage 100 in the oil passage structure 10 of the present embodiment and the destination of the oil when adjusting the pressure will be described.

The oil passage structure 10 has a relief valve 63 (relief mechanism) provided in the middle of the oil passage 100 . Further, as shown in FIG. 11(a), on the downstream side of the relief valve 63, the first passage 54a and the second passage 54c (the discharge chamber 54) are branched. The first passage 54 a communicates with the oil reservoir 50 . A discharge port 54b (communication hole) that communicates with the motor chamber 41 is provided in the second passage 54c (discharge chamber 54).

According to the oil passage structure 10 , part of the relieved oil can flow into the motor chamber 41 to cool the first electric motor 20 . As a result, the oil passage structure 10 can efficiently cool the first electric motor 20 by using the relieved oil especially when the first electric motor 20 is in a high load state.

Further, in the oil passage structure 10 , the discharge port 54 b is arranged at a position overlapping the lower portion of the first electric motor 20 .

With the configuration described above, the oil passage structure 10 can cool the lower portion of the first electric motor 20, which is conventionally disadvantageous for cooling. Specifically, in the conventional oil passage structure, when the motor is in a high-load state, the motor is positively cooled by pouring oil from above. is disadvantageous. On the other hand, in the oil passage structure 10, the oil can be supplied from the discharge port 54b (communication hole) to the lower portion of the first electric motor 20 to cool the lower side of the first electric motor 20, which is disadvantageous for cooling. can.

In addition, in the oil passage structure 10, the discharge port 54b is located below the relief valve 63 (relief mechanism) Lw, and the second passage 54c has an oil reservoir shape (see FIG. 11A). ). In other words, the second passageway 54c of the oil passage structure 10 constitutes a discharge chamber 54 with a certain volume in which oil can be collected.

Therefore, in the oil passage structure 10, even when the relief valve 63 is closed, the oil can remain in the second passage 54c (release chamber 54) having an oil reservoir shape for a while. This allows the oil passage structure 10 to sequentially supply oil to the motor chamber 41 , which is advantageous for cooling the first electric motor 20 . More specifically, even if the rotation speed of the first electric motor 20 decreases, the temperature of the first electric motor 20 does not immediately decrease. can be supplied and cooled, which is advantageous for cooling the first electric motor 20 .

As described above, the oil passage structure 10 has the relief valve 63 that partially opens the oil passage 100 according to the pressure of the oil passage 100 . In addition, in the oil passage structure 10, when the pressure in the oil passage 100 becomes excessive (above a certain level), the relief valve 63 operates to allow the oil to flow out from the oil passage 100 to the oil reservoir 50; Oil flows from the oil passage 100 into the second passage 54c through which the oil flows into the motor chamber 41 side of the transaxle housing 40 in which the electric motor 18 (first electric motor 20) is accommodated.

The oil passage structure 10 also includes a discharge chamber 54 (third recess 45c) into which oil flows when the relief valve 63 is actuated, and a partition plate 61 (partition plate) provided to partition the discharge chamber 54 and the oil passage 100. part). A discharge hole 55 (fourth hole 61d) that allows communication between the discharge chamber 54 and the oil passage 100 is formed in the partition plate 61 (partition portion). In the oil passage structure 10 , the relief valve 63 closes the discharge hole 55 , and when the pressure in the oil passage 100 reaches or exceeds a certain level, the relief valve 63 retreats toward the discharge chamber 54 to open the discharge hole 55 .

Specifically, as shown in FIG. A space through which oil passes (becomes an oil flow path) is formed by the fourth concave portion 62a.

More specifically, the first recess 45a formed in the transaxle housing 40 is closed by the oil pump body 62 to form a space (guide chamber 51) into which the oil that has passed through the strainer 64 flows. In addition, a pump gear 60a that constitutes an oil pump 60 is accommodated in the second concave portion 45b to form a pump accommodating chamber 52. As shown in FIG. Further, the fourth concave portion 62a of the oil pump body 62 is closed by a partition plate 61 to form a pressure regulating chamber 53 into which oil conveyed from the oil pump 60 flows. Further, the third recess 45c formed in the transaxle housing 40 is closed by the partition plate 61, and the first passage 54a and the release chamber 54 (second It forms two passages 54c). The first passage 54a and the second passage 54c form a branched oil passage 100, and the oil that has flowed in from the discharge hole 55 is discharged in a branched manner.

In the oil passage structure 10 of the present embodiment, a passage (second passage 54c) toward the motor chamber 41 side is provided in addition to the passage (first passage 54a) toward the oil reservoir 50 for the oil to be relieved. As a result, in the oil passage structure 10 of the present embodiment, part of the oil returned to the oil reservoir 50 to adjust the pressure is actively utilized for cooling the first electric motor 20 .

In this way, according to the oil passage structure 10, relief is provided at the necessary timing (when the rotation speed of the first electric motor 20 increases together with the rotation speed of the engine and the cooling of the first electric motor 20 becomes particularly necessary). The oil can be efficiently used to cool the first electric motor 20 .

Thus, according to the oil passage structure 10 , the structure for adjusting the pressure of the oil passage 100 (the structure for returning the oil to the oil reservoir 50 ) and the discharged oil can be utilized for cooling the first electric motor 20 . can. As a result, it is possible to efficiently cool the first electric motor 20 while suppressing costs without providing a very complicated mechanism.

<3. Regarding the position of the temperature sensor>
Next, the mounting position of the temperature sensor 86 in the oil passage structure 10 of this embodiment will be described. In the oil passage structure 10, even when the vehicle V is running in an EV mode (when the engine is stopped), the temperature sensor 86 is always kept immersed in oil, and the temperature sensor 86 detects air. It is possible to suppress the occurrence of errors.

The oil passage structure 10 includes a first oil passage 49 provided toward the axial center of the first electric motor 20 and a dead end portion 47 (second oil passage) branched from the first oil passage 49 and formed in a dead end shape. ). Further, in the oil passage structure 10 , the temperature sensor 86 is arranged on the lower Lw side than the branch position with the first oil passage 49 in the cul-de-sac portion 47 (second oil passage).

According to the oil passage structure 10, even when the oil pressure is lost when the oil pump 60 is stopped (during EV running), the dead end portion 47 (second oil passage) can always be filled with oil. As a result, the oil passage structure 10 can prevent problems such as the temperature sensor 86 not being able to detect the temperature of the oil.

In the oil passage structure 10 , the branching portion of the first oil passage 49 and the dead end portion 47 (second oil passage) and the temperature sensor 86 are located axially laterally of the first electric motor 20 .

According to the above configuration, it is possible to detect the temperature of the oil immediately upstream of the electric motor, which particularly requires temperature control, and improve the controllability of the first electric motor 20 . More specifically, according to the above configuration, after being cooled by the oil cooler 70, the oil that has not yet been subjected to cooling or lubrication (oil whose temperature has hardly risen since being cooled, or fresh oil) is removed. , into the cul-de-sac 47 . In addition, it is possible to detect the temperature of the oil in the vicinity of the first electric motor 20 where the temperature detection of the oil is most required.

As described above, the oil passage structure 10 of this embodiment has the temperature sensor 86 . Further, the oil passage 100 of the oil passage structure 10 is a dead end 47 that is partially shaped like a dead end, and the temperature sensor 86 is arranged in the dead end 47 . Further, a dead end 47 is formed on the lower Lw side in the oil flow direction. In addition, the dead end portion 47 is formed in the vicinity of the turning corner in the route of the oil passage 100 .

More specifically, as shown in FIG. 4 , the second supply path 112 has a path that slopes from the upper Up side of the transaxle housing 40 to the lower Lw side, and extends toward the center of the mounting portion 46 (axis At the position where the core C is located), the direction of oil flow changes so that it faces the axial direction G of the rotor shaft 24 (becomes a bend).

The cul-de-sac portion 47 is formed at the end of the flow path formed so as to protrude (slightly over) the downwardly inclined path of the second supply path 112 . In other words, the cul-de-sac 47 is formed like a recess at the end of the flow path directed downward Lw. Therefore, even when oil is not conveyed through the oil passage 100 (even when the operation of the oil pump 60 is stopped), the dead end 47 is always filled with oil.

According to the oil passage structure 10 of the present embodiment, it is possible to maintain a state in which the temperature sensor 86 is always in contact with the oil as a state in which the dead end 47 is always filled with oil. In other words, the temperature sensor 86 is always immersed in oil, and the concern that the temperature sensor 86 detects air can be eliminated. As a result, the oil passage structure 10 can reduce temperature detection errors and detect the oil temperature with high accuracy.

Here, in the transaxle 1 of the present embodiment, as described above, in order to suppress corrosion (electrolytic corrosion) due to the potential difference between the first electric motor 20 and the transaxle housing 40, the electrolytic corrosion cover 80 is attached to the mounting portion 46. is provided. An insulating plate 84 is interposed between the electrolytic corrosion cover 80 and the transaxle housing 40 .

As described above, the electrolytic corrosion cover 80 is provided between the first electric motor 20 and the transaxle housing 40 . Further, in the oil passage structure 10, the electrolytic corrosion cover 80 and the insulating plate 84 are arranged so as to restrict the movement of the temperature sensor 86 in the direction away from the cul-de-sac 47 (toward the motor chamber 41). It functions as a retainer for 86.

More specifically, as shown in FIG. 7 , the temperature sensor 86 has its tip end (detection part) fitted in the dead end 47 and the other end exposed from the dead end 47 toward the first electric motor 20 . is doing. The other end side of the temperature sensor 86 is housed in the space of the mounting portion 46, and the other end side is located between the electrolytic corrosion cover 80 and the transaxle housing 40 via the insulating plate 84. . Therefore, when the temperature sensor 86 is displaced away from the cul-de-sac 47, it is blocked by the insulating plate 84 and the displacement is limited. As a result, in the oil passage structure 10 , the insulating plate 84 and the electrolytic corrosion cover 80 can function as retainers for the temperature sensor 86 .

As described above, according to the oil passage structure 10, the electrolytic corrosion cover 80 and the insulating plate 84 (existing parts) provided for suppressing electrolytic corrosion function as stoppers for the temperature sensor 86. Fastening members and the like for fixing 86 can be reduced.

In the oil passage structure 10 of the present embodiment, the electrolytic corrosion cover 80 and the insulating plate 84 have been described as examples of the members (intervening members) interposed between the first electric motor 20 and the transaxle housing 40. The oil passage structure of the invention is not limited to this embodiment. For example, in the oil passage structure of the present invention, either an electrolytic corrosion cover or an insulating plate may be interposed between the electric motor and the case body. Further, in the oil passage structure of the present embodiment, the intervening member is a member for suppressing corrosion (electrolytic corrosion) due to the potential difference between the electric motor and the case body. is not limited to this. That is, the member interposed between the electric motor and the case body may be another member such as a bearing.

<4. Regarding the oil supply to the rotor shaft>
Next, details of the third supply passage 113 and details of the nozzle portion 82 and the rotor shaft 24 in the oil passage structure 10 of the present embodiment will be described.

As described above, the nozzle portion 82 is provided in the oil passage structure 10 of the present embodiment. The nozzle portion 82 is provided for the electrolytic corrosion cover 80 . The nozzle portion 82 has a discharge port 82a. The nozzle portion 82 is supplied with oil from the oil passage 100 (the third supply passage 113). The nozzle portion 82 is arranged in the hollow portion 24a.

As shown in FIG. 7, the ejection port 82a opens toward the lower side Lw. Further, as described above, the rotor shaft 24 has a hollow portion 24a and a shaft communication hole 24b that communicates with the outside of the rotor shaft 24 from the hollow portion 24a.

In the oil passage structure 10 of this embodiment, the discharge port 82a of the nozzle portion 82 opens downward. As a result, the oil guided to the nozzle portion 82 hits the tip wall of the nozzle portion 82 and flows downward, drops from the discharge port 82a, and is supplied to the hollow portion 24a of the rotor shaft 24. As shown in FIG. As a result, the oil passage structure 10 can suppress the momentum of the oil supplied into the rotor shaft 24 and allow the oil to efficiently reach desired positions such as the shaft communication hole 24 b of the rotor shaft 24 .

Furthermore, in the oil passage structure 10 of the present embodiment, the insulating plate 84 functions as a member (dividing portion) that partitions the oil passage 100 (the third supply passage 113 ) and the internal space of the nozzle portion 82 . The insulating plate 84 (partition wall) is formed with a through hole 84a (orifice) that allows the oil passage 100 and the internal space of the nozzle portion 82 to communicate with each other.

The through hole 84a is provided so as to be offset with respect to the discharge port 82a.

Therefore, in the oil passage structure 10, the oil that has passed through the through hole 84a hits the inner wall of the tip of the nozzle portion 82, and flows down from the discharge port 82a in a state where momentum is reduced. As a result, the oil can be efficiently guided to the shaft communication hole 24b.

As shown in FIG. 7, the rotor shaft 24 is provided with a protruding portion 24c that protrudes toward the inner periphery on the inner periphery of the rotor shaft 24 . The projecting portion 24c is provided so as to restrict oil from flowing out in the axial direction G of the rotor shaft 24 from the hollow portion 24a. The protrusion 24c is formed to protrude from the inner wall of the rotor shaft 24 toward the shaft core C. As shown in FIG. Thus, in the oil passage structure 10, the oil in the hollow portion 24a of the rotor shaft 24 is restricted from flowing out from the hollow portion 24a. Thereby, the oil passage structure 10 can efficiently store the oil in the rotor shaft 24 .

That is, according to the oil passage structure 10, the flow of oil is restricted by the protrusion 24c, and the oil tends to accumulate in the portion inside the rotor shaft 24 where the shaft communication hole 24b is provided. As a result, the oil can be reliably supplied to the rotor 22 and the oil can be made to run along the inner circumference of the rotor shaft 24 to cool the rotor 22 by heat exchange.

The oil that has reached the shaft communication hole 24b from the hollow portion 24a is guided in the radial direction of the first electric motor 20 by the centrifugal force generated by the rotation of the rotor shaft 24, and contributes to the cooling of the first electric motor 20 from the inside.

Here, the arrangement of the discharge port 82a, the protrusion 24c, the shaft communication hole 24b, and the bearing 88 in the axial direction G will be described. First, the discharge port 82a is located between the protrusion 24c and the shaft communication hole 24b in the axial direction G of the rotor shaft 24. As shown in FIG. As shown in FIG. 7, the oil discharged from the discharge port 82a flows downward Lw. Further, the projecting portion 24c is formed at a position near the position where the oil discharged from the discharge port 82a flows down. Therefore, the oil passage structure 10 can allow the oil to reach the communication hole while efficiently retaining the oil supplied to the inside of the rotor shaft 24 in the hollow portion 24a. If the discharge port 82a were located at a position separate from the projection 24c, it would be impossible to accumulate the amount of oil that flows outside the projection 24c beyond the projection 24c. is assumed. In contrast, in the oil passage structure 10, the discharge port 82a is provided near the projection 24c (and between the projection 24c and the shaft communication hole 24b). Therefore, in the oil passage structure 10 , the oil can reliably pass over the protrusion 24 c to lubricate the bearing 88 .

From another point of view, the position of the shaft communication hole 24b and the discharge port 82a in the oil passage structure 10 will be described. The length of the nozzle portion 82 is set so as to be in front of the axial communication hole 24b. Therefore, by shortening the length of the nozzle portion 82, the oil passage structure 10 can achieve cost reduction and weight reduction.

Further, as shown in FIG. 7, a bearing 88 that supports the rotor shaft 24 is attached near the protrusion 24c. Furthermore, between the protrusion 24c and the outer peripheral surface of the nozzle portion 82, a gap S is formed through which oil can flow. Therefore, in the oil passage structure 10, the oil supplied to the inside of the rotor shaft 24 can be efficiently kept in the hollow portion 24a and part of the oil can flow out from the hollow portion 24a to lubricate the bearing 88.

Although the oil passage structure 10 according to the embodiment of the present invention has been described above, the present invention is not limited to the above-described embodiment, and each function and configuration can be changed as appropriate.

For example, in the above-described embodiment, an example is shown in which the cooled oil is distributed to three locations. The oil may be distributed to and conveyed.

Further, in the oil passage structure 10 according to the above-described embodiment, an example in which the nozzle portion 82 is provided in the electrolytic corrosion cover 80 is shown, but the oil passage structure of the present invention is not limited to this, and the nozzle portion is It may be provided as a separate member from the electrolytic corrosion cover.

INDUSTRIAL APPLICABILITY The oil passage structure of the present invention can be suitably employed for cooling an electric motor.

1 transaxle 10 oil passage structure 20 first electric motor (electric motor)
40 transaxle housing (case body)
47 dead end (second oil passage)
84 insulating plate (intervening member, plate member)
86 temperature sensor 100 oil passage

Claims (3)

an oil passage serving as a flow passage for oil that cools the electric motor;
a temperature sensor that detects the temperature in the oil passage,
The oil passage is
a first oil passage provided to face the axial center of the electric motor;
a second oil passage branched from the first oil passage and formed in the shape of a dead end;
The temperature sensor is arranged in the second oil passage below a branch position with the first oil passage ,
a case body that houses the electric motor;
an intervening member interposed between the electric motor and the case body,
The temperature sensor is
inserted into the second oil passage from the inside of the case body,
The oil passage structure , wherein the intervening member restricts the movement of the case body toward the inside . 2. The oil passage structure according to claim 1, wherein the branched portion of the first oil passage and the second oil passage and the temperature sensor are positioned axially laterally of the electric motor. an oil passage serving as a flow passage for oil that cools the electric motor;
a temperature sensor that detects the temperature in the oil passage,
The oil passage is
a first oil passage provided to face the axis of the electric motor;
a second oil passage branched from the first oil passage and formed in a dead end,
The temperature sensor is arranged in the second oil passage below a branch position with the first oil passage,
The second oil passage is arranged such that the oil flowing into the second oil passage is positioned upstream of the oil flow from the branch position of the first oil passage,
The oil passage structure, wherein oil not used for cooling the electric motor flows into the second oil passage.

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