JP5262062B2 - Breather layout - Google Patents

Description

  The present invention relates to a breather arrangement structure, and more particularly, to a breather arrangement structure in an in-wheel motor drive device having a structure in which a pressure distribution in a housing that houses a motor and a reduction gear becomes non-uniform.

  Conventionally, a breather mounting structure is known in which a breather is provided at a position above the rotational axis of the in-wheel motor and between the in-wheel motor and the wheel (see, for example, Patent Document 1). .)

In this mounting structure, by installing the breather at a deep position in the wheel, it is possible to prevent foreign matters such as stones, sand, and dust that are rolled up with the rotation of the wheel from directly colliding with the breather.
JP 2005-324722 A

  However, since the mounting structure described in Patent Document 1 determines the arrangement of the breather without considering the pressure distribution in the housing that houses the motor and the speed reducer, the breather is placed at a position that leads to a portion where the pressure in the housing is high. If it is arranged, there is a risk of causing leakage of lubricating oil or coolant, and this cannot be applied as it is to an in-wheel motor drive device having a structure in which the pressure distribution in the casing becomes non-uniform.

  In view of the above, the present invention has an object of providing an arrangement structure of a breather applicable to an in-wheel motor drive device having a structure in which pressure distribution in a housing that houses a motor and a speed reducer is non-uniform. And

  In order to achieve the above-mentioned object, the arrangement structure of the breather according to the first invention is an in-wheel motor drive device having a structure for generating a low-pressure portion and a high-pressure portion in a housing that houses a motor and a reduction gear. A breather arrangement structure is characterized in that the breather is arranged at a position leading to the low-pressure portion.

  Moreover, 2nd invention is the arrangement | positioning structure of the breather which concerns on 1st invention, Comprising: The said high voltage | pressure part is a flow path of the pressurized coolant which surrounds the heat_generation | fever part of a motor.

  Moreover, 3rd invention is the arrangement structure of the breather which concerns on 1st or 2nd invention, Comprising: The said low voltage | pressure part is the space which accommodates a reduction gear, It is characterized by the above-mentioned.

  Further, a fourth invention is a breather arrangement structure according to any one of the first to third inventions, and is a space surrounded by other members in the in-wheel motor drive device. The breather is arranged in a space that communicates with the external space.

  The fifth invention is a breather arrangement structure according to any one of the first to fourth inventions, wherein the space surrounded by the other members is a space surrounded by a motor housing and a brake dust cover. It is characterized by being.

  According to a sixth aspect of the present invention, there is provided a breather arrangement structure according to any one of the first to fifth aspects of the invention, wherein the motor housing includes a recess for accommodating the breather.

  According to a seventh aspect of the present invention, there is provided a breather arrangement structure according to any one of the first to sixth aspects, wherein the brake dust cover includes a recess for accommodating the breather.

  By the above-mentioned means, this invention can provide the arrangement structure of the breather applicable to the in-wheel motor drive device provided with the structure where the pressure distribution in the housing | casing which accommodates a motor and a reduction gear becomes non-uniform | heterogenous.

  Hereinafter, the best mode for carrying out the present invention will be described with reference to the drawings.

  FIG. 1 is a diagram showing a configuration example of an in-wheel motor drive device having a breather arrangement structure according to the present invention. The in-wheel motor drive device 100 includes a breather 1, a brake rotor 2, a brake dust cover 3, and a motor. A housing 4, a motor housing cover 5, a motor 6, a speed reducer 7, a power transmission member 8, a hub 9 and a wheel 10 are configured.

  The breather 1 is a device for adjusting the pressure in the housing that houses the motor 6 and the speed reducer 7. Here, the “housing” is a case composed of the motor housing 4, the motor housing cover 5, the power transmission member 8, and the ring gear 73 of the speed reducer 7, in which the motor 6 and the speed reducer 7 are accommodated. The case to do.

  The breather 1 is composed of, for example, a relief valve using a spring or a film that allows only gas to pass through. The motor 6 or the speed reducer 7 accommodated in the casing is heated, and the gas or liquid in the casing in contact with them is heated. When the pressure in the casing increases due to expansion, the expanded gas is discharged to the outside of the casing, while the motor 6 or the speed reducer 7 accommodated in the casing is cooled and the casing is in contact with them. When the gas or liquid returns to the original state, the gas already discharged is taken into the housing from the outside of the housing.

  The brake rotor 2 is a member that constitutes a braking device, and the braking device exerts braking force by sandwiching the brake rotor 2 that rotates together with the wheels (including the hub 9 and the wheel 10) between the brake pads of the brake caliper. Stop wheel rotation.

  The brake dust cover 3 is a cover that covers the brake rotor 2 in order to prevent foreign matter from adhering to the brake rotor 2.

  The motor housing 4 is a part of a housing for housing the motor 6 and the speed reducer 7 and is attached to the vehicle via the knuckle arm 11 or the suspension arm.

  The motor housing cover 5 is a part of a housing for housing the motor 6 and is attached to the motor housing 4.

  The motor 6 is an electric motor attached to each wheel, rotates the axle, and transmits the torque to the wheel via the speed reducer 7, the power transmission member 8, the hub 9 and the wheel 10.

  The motor 6 includes a stator 60, a coil end cover 61, and a rotor 62, and includes a coolant flow path 63 serving as a high-pressure portion between the stator 60 and the coil end cover 61. The detailed structure of the coolant channel 63 will be described later.

  The speed reducer 7 is a mechanical device that generates a high torque by reducing the rotational speed of the motor 6. For example, the speed reducer 7 is a planetary gear device that rotates a sun gear 70 that is integrated with an axle so that the sun gear 70 and a ring are rotated. The planetary gear 71 rotates while rotating with the gear 73, and torque is transmitted to the power transmission member 8 that is spline-fitted to the planetary carrier 72 in the area FA in the figure.

  The space around the motor 6 in the housing (hereinafter referred to as “motor chamber”) and the space around the reduction gear 7 in the housing (hereinafter referred to as “reduction gear chamber”) are the respective spaces. It may be separated by a wall so as to prevent the free propagation of pressure. For example, a relief valve is arranged on the wall and a coil that generates heat generates a motor chamber that is likely to be relatively high pressure and a relatively low pressure. You may make it isolate | separate from the reducer room which tends to become.

  In this case, when the pressure in the motor chamber exceeds a predetermined pressure, the pressure propagates to the speed reducer chamber via the relief valve, and when the pressure in the speed reducer chamber exceeds the predetermined pressure thereafter, the speed reducer chamber The gas in the speed reducer chamber is released to the outside through the breather 1 attached to.

  As a result, the pressure in the reduction gear chamber can be reduced, and consequently the pressure in the motor chamber can be reduced.

  The power transmission member 8 is a disk-shaped member disposed so as to cover the vehicle outer side of the speed reducer 7 (the left side in the drawing corresponds to the vehicle outer side, and the right side in the drawing corresponds to the vehicle inner side). The hub 9 is connected to the hub 9 and supported by two rows of angular ball bearings composed of an inner race part integrated with the ring gear 73 and an outer race part integrated with the hub 9. Rotate with. The power transmission member 8 and the hub 9 may be integrated.

  The hub 9 is a member for transmitting the torque transmitted from the power transmission member 8 to the wheel 10, and the wheel 10 is a member for transmitting the torque transmitted from the hub 9 to the wheel. The bolt 9 is attached to the hub 9 and the hub 9 and the wheel 10 rotate together.

  Here, the configuration of the coolant flow path 63 will be described with reference to FIGS. 2 and 3. 2 is an exploded view of the motor 6, and FIG. 3 is an enlarged view of a region III shown in FIG.

  As shown in FIG. 2, the motor 6 includes a motor housing 4, a stator 60, a coil end cover 61, and a motor housing cover 5, and the motor housing cover 5 and the stator are attached by attaching the motor housing cover 5 to the motor housing 4. The coil end cover 61 is sandwiched between the coil end cover 61 and the coil end cover 61.

  The coil end cover 61 is arranged so as to be able to finely move between the motor housing cover 5 and the stator 60 without being fixed to either of the motor housing cover 5 and the stator 60, and forms a coolant flow path 63 between the coil end cover 61 and the stator 60 (FIG. 3). reference.).

  Further, the coil end cover 61 forms a minute gap between the stator 60 and the motor housing cover 5 so that the gap can be filled with the coolant.

  The black-colored portion in FIG. 3 indicates a high-pressure portion where the coolant pressurized by a pump (not shown) remains in its pressurized state, and is between the coolant channel 63 and the stator 60. And a small gap between the motor housing cover 5 are included in the high-pressure portion.

  The pressurized coolant expels air functioning as a heat insulating material that exists around the stator 60 toward the rotor 62, the gap between the stator 60 and the coil end cover 61, and the coil end cover 61 and A gap between the motor housing cover 5 and the motor housing cover 5 is filled to form a heat transfer path from the coil of the stator 60 to the motor housing cover 5, and the heat generated from the coil is efficiently radiated from the motor housing cover 5 to form the coil. The cooling effect is further enhanced.

  Further, the arrows in FIG. 3 indicate the coolant leaking from the minute gaps, and this leaked coolant is used as an oil tank (not shown) after being used as a fluid for lubricating the axle of the motor 6 and the speed reducer 7. S.)

  In this way, the motor 6 can efficiently discharge the heat generated in the coils of the stator 60 while circulating the coolant.

  On the other hand, since the motor 6 feeds the pressurized coolant around the stator 60 in order to enhance the cooling effect, if the breather 1 is arranged at a position where the pressurized coolant is in a space, the in-wheel The motor drive device 100 may leak the coolant pressurized through the breather 1 to the outside.

  Therefore, the in-wheel motor drive device 100 according to the present invention is provided with the breather 1 having the passage PT1 leading to the space where the pressurized coolant does not exist at the upper part of the wheel rotation shaft.

  FIG. 4 is an enlarged view of the region IV shown in FIG. 1 and shows the breather 1 having a passage PT1 extending upward from a space in which the speed reducer 7 is accommodated.

  The passage PT1 is preferably formed to be sufficiently thin so that the cooling or lubrication liquid existing in the casing does not jump up and reaches the tip (entrance / exit) of the breather 1, and is also used for the cooling or lubrication existing in the casing. In order to prevent the liquid from flowing in, it is directed straight upward in the vertical direction, but may be directed obliquely upward, and may have a portion that is bent or refracted in the middle while facing upward or obliquely upward. .

  In this way, the passage PT1 can allow only the air in the casing to enter and exit through the breather 1 while preventing the liquid in the casing from leaking to the outside.

  As shown in FIG. 4, the breather space SP in which the breather 1 exists is formed by the brake dust cover concave portion 3a and the motor housing concave portion 4a, and communicates with the external space through the narrow path NP.

  Here, the narrow path NP refers to a passage having a narrower width than the length, width, and height of the breather space SP, and preferably extends upward in the vertical direction but extends in the other direction. There may be. The narrow path NP may be a tubular passage, and extends substantially straight toward the outside, but may extend while being bent or bent, and may have a labyrinth structure. This is to prevent foreign matter from entering the breather space SP from the outside.

  The breather space SP may be configured such that only the brake dust cover 3 has the recess 3a and the motor housing 4 does not have the recess 4a. Conversely, only the motor housing 4 has the recess 4a. The brake dust cover 3 may be configured in such a manner that it does not have the recess 3a. This is to make the processing of each component easier.

  In this way, the breather space SP can feed air free from contamination through the breather 1 while preventing foreign matter such as muddy water from entering and adhering to the tip of the breather 1. it can.

  Further, the breather space SP can eliminate the necessity of attaching a dedicated cover to the breather 1 for preventing the adhesion of foreign matters, and can prevent an increase in manufacturing cost of the in-wheel motor drive device 100.

  Next, another configuration example of the in-wheel motor drive device having the breather arrangement structure according to the present invention will be described with reference to FIG.

  The in-wheel motor drive device 200 includes a breather 1 having a passage PT2 that leads to a space where no pressurized coolant exists, at the upper part of the wheel rotation shaft. Since other components are common to the in-wheel motor drive device 100, description thereof is omitted.

  The passage PT2 extends outward from the space in which the motor 6 is accommodated, and further extends upward through a refractive path or a curved path. In addition, the space in the housing | casing which channel | path PT2 is connected is space around the motor 6 without the pressurized coolant.

  The passage PT2 is bent or bent halfway so that the cooling or lubricating liquid existing in the casing does not jump and reaches the tip of the breather 1, and the cooling or lubricating liquid existing in the casing does not flow. The part after refraction or bending is directed straight upward in the vertical direction, but the part after refraction or bending may be directed obliquely upward, and further, the part before refraction or bending extends horizontally outside the vehicle. Instead, it may extend outward of the vehicle while tilting upward in the vertical direction.

  In this way, the passage PT2 can allow only the air in the casing to enter and exit through the breather 1 while preventing the liquid in the casing from leaking to the outside.

  With the above configuration, the in-wheel motor drive device in which the heat generating part in the motor chamber is cooled by the pressurized coolant places the breather 1 at a position that leads to the low-pressure space in the housing, so that the liquid is discharged from the breather 1. Can be prevented from leaking out.

  Moreover, the in-wheel motor drive device provided with the arrangement | positioning structure of the breather 1 which concerns on this invention arrange | positions the breather 1 in the recessed space where foreign materials, such as muddy water, cannot enter easily, surrounded by the brake dust cover 3 and the motor housing 4. By doing so, it is possible to prevent foreign matter from adhering to the part of the breather 1 where air enters and exits.

  Although the preferred embodiments of the present invention have been described in detail above, the present invention is not limited to the above-described embodiments, and various modifications and substitutions can be made to the above-described embodiments without departing from the scope of the present invention. Can be added.

  For example, in the above-described embodiment, the breather 1 is disposed in a space surrounded by the brake dust cover 3 and the motor housing 4, but the space surrounded by the knuckle arm 11 and the motor housing 4 or the motor housing cover. 5 and a space surrounded by the motor housing 4 may be arranged in a space surrounded by other component groups constituting the in-wheel motor drive devices 100 and 200, or a space formed only by the motor housing 4. It may be arranged in a space surrounded by a single component, such as inside. This is because the same effect of preventing foreign matter from adhering to the tip of the breather 1 can be obtained in a space where foreign matter is difficult to be mixed.

It is a figure (the 1) which shows the structural example of the in-wheel motor drive device provided with the arrangement structure of the breather which concerns on this invention. It is an exploded view of a motor. It is an enlarged view of the area | region III shown in FIG. It is an enlarged view of the area | region IV shown in FIG. It is FIG. (2) which shows the structural example of the in-wheel motor drive device provided with the arrangement structure of the breather which concerns on this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Breather 2 Brake rotor 3 Brake dust cover 3a Brake dust cover recessed part 4 Motor housing 4a Motor housing recessed part 5 Motor housing cover 6 Motor 7 Reducer 8 Power transmission member 9 Hub 10 Wheel 11 Knuckle arm 60 Stator 61 Coil end cover 62 Rotor 63 Coolant flow path 70 Sun gear 71 Planetary gear 72 Planetary carrier 73 Ring gear 100, 200 In-wheel motor driving device FA Fitting area NP Narrow path PT1, PT2 Path SP Breather space

Claims (6)

An arrangement structure of a breather in an in-wheel motor drive device having a structure for generating a low-pressure part and a high-pressure part in a housing that houses a motor and a speed reducer,
The gas in the housing is released to the breather space through the breather,
The breather space communicates with an external space by a narrow path having a narrower width than the breather space;
The breather, in the breather space, Ru is placed in a position communicating with the low pressure portion,
Breather arrangement structure characterized by that. An arrangement structure of a breather in an in-wheel motor drive device having a structure for generating a low-pressure part and a high-pressure part in a housing that houses a motor and a speed reducer,
A breather is disposed at a position communicating with the low-pressure portion in a space surrounded by the motor housing and the brake dust cover of the in-wheel motor drive device and communicating with the external space through a narrow path .
Breather arrangement structure characterized by that. The motor housing includes a recess that houses the breather.
The arrangement structure of the breather according to claim 2 . The brake dust cover includes a recess that houses the breather.
Arrangement of the breather according to claim 2 or 3, characterized in that. The high-pressure part is a flow path of pressurized coolant that surrounds the heat-generating part of the motor.
The arrangement structure of a breather according to any one of claims 1 to 4 . The low-pressure portion is a space that houses a reduction gear,
The arrangement structure of the breather according to any one of claims 1 to 5 .

Images