JP6990106B2 - Power transmission device - Google Patents

Description

The present invention relates to a power transmission device.

Vehicles such as automobiles are equipped with a power transmission device having a rotating member such as a transmission or a differential device. In the power transmission device, for example, in order to ensure the lubricity of the bearing member that supports the rotating member, lubricating oil is stored in the case of the power transmission device. In the power transmission device, it is required to reduce the spin loss (drive loss) in order to reduce the fuel consumption and the power consumption rate of the vehicle. In order to reduce such spin loss, it is effective to reduce the drag torque of the lubricating oil. Therefore, by providing a baffle plate around the rotating member or lowering the oil level of the lubricating oil, the stirring resistance of the lubricating oil applied to the rotating member is reduced.

For example, Patent Document 1 is a lubrication structure for a vehicle transmission that introduces and lubricates lubricating oil for a converter case into a differential device due to the rotational operation of the ring gear, and is arranged so as to cover the ring gear and is a converter case. A lubrication structure having a baffle plate capable of separating a ring gear from the oil level of the lubricating oil inside is disclosed. In Patent Document 1, the baffle plate is provided with a support means for supporting a constant distance from the ring gear, so that when the ring gear scoops up the lubricating oil in the converter case, the ring gear does not scoop up the lubricating oil more than necessary. It is possible to reduce the stirring resistance applied to the oil.

Japanese Unexamined Patent Publication No. 2012-62995

Here, lubricating oil is supplied to the bearing member that supports the rotating shaft of the rotating member such as a ring gear in order to ensure the lubricity of the sliding portion. The height of the oil level of the lubricating oil should be at least from the position of the lower end of the bearing member so that the lubricity of the sliding parts can be ensured even when the vehicle is stopped for a long time and then restarted, or when traveling at extremely low speeds. Must also be set on. That is, the height of the oil level of the lubricating oil is determined by the layout of the power transmission device and cannot be freely lowered. Even under such restrictions, if the drag torque of the lubricating oil due to the rotation of the rotating member can be reduced, the spin loss of the power transmission device can be further reduced.

Therefore, the present invention has been made in view of the above problems, and an object of the present invention is lubrication of a bearing member that rotatably supports a rotating member when the rotating member is not rotating or is rotating at an extremely low speed. It is an object of the present invention to provide a new and improved power transmission device capable of reducing spin loss during rotation of a rotating member while ensuring the performance.

In order to solve the above problems, according to a certain viewpoint of the present invention, a case in which lubricating oil is stored, a rotating member whose lower portion is immersed in the lubricating oil and housed in a case so as to be axially rotatable, and a rotating member. The plate member is provided with a plate member arranged with a gap interposed therebetween at least at the lower portion of the plate member, and a capacitance portion having a plate thickness larger than that of the other portion is provided in a part of the plate member. Is displaceable with the rotation of the rotating member, and the capacitive portion is immersed in the lubricating oil when the rotating member is not rotating, and the lubricating oil flows with the rotation of the rotating member along the rotation direction of the rotating member. A power transmission device is provided which is located above the oil level of the lubricating oil by rotating with the oil.

The plate member may be axially rotatable coaxially with the rotating member.

The capacitance portion may be provided on the tip end side in the rotation direction of the plate member.

The capacitance portion may be provided on the surface of the plate member opposite to the surface facing the rotating member.

The specific gravity of the capacitive portion may be larger than the specific gravity of the lubricating oil.

A stopper may be provided that defines the maximum displacement position of the plate member.

The plate member may be a baffle plate.

As described above, according to the present invention, the spin loss during rotation of the rotating member is reduced while ensuring the lubricity of the bearing member that rotatably supports the rotating member when the rotating member is not rotating or rotating at an extremely low speed. can do.

It is explanatory drawing which shows the structure of the power transmission apparatus which concerns on embodiment of this invention. It is sectional drawing which shows the structure of the power transmission apparatus which concerns on the same embodiment. It is a perspective view which shows the baffle plate provided in the power transmission apparatus which concerns on the same embodiment. It is a top view which shows the baffle plate provided in the power transmission apparatus which concerns on this embodiment. It is explanatory drawing which shows the operation of a baffle plate. It is explanatory drawing which shows the structural example which defines the maximum displacement position of a baffle plate.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the present specification and the drawings, components having substantially the same functional configuration are designated by the same reference numerals, so that duplicate description will be omitted.

<1. Overall configuration example of power transmission device>
1 and 2 are explanatory views showing the configuration of the power transmission device 10 according to the present embodiment. FIG. 1 is a schematic view of the power transmission device 10 as viewed along the rotation axis X of the rotating member 20, and FIG. 2 is a schematic view of the I-I cross section of FIG. 1 as viewed in the direction of an arrow. 1 and 2 show a non-operating state of the power transmission device 10, that is, a state in which the rotating member 20 is not rotationally driven.

The power transmission device 10 includes a case 11, a rotating member 20, and a baffle plate 30. The rotating member 20 is housed inside the case 11 and is rotatably supported with respect to the case 11. The rotating member 20 has shaft portions 21a and 21b extending on both sides of the rotating axis X. The shaft portions 21a and 21b are supported by the case 11 by the bearing members 23a and 23b. As a result, the rotating member 20 is rotatably supported with respect to the case 11.

The power transmission device 10 may be, for example, a front differential device that distributes a driving force to the left and right front wheels of the vehicle. In this case, the rotating member 20 corresponds to a ring gear that meshes with a drive pinion gear (not shown) inside the case (diff case) 11. A drive shaft (not shown) is integrally formed in the drive pinion gear, and when the power of the engine is transmitted to the drive shaft via the propulsion shaft, the drive pinion gear rotates, and the ring gear is rotated accordingly. The drive pinion gear is rotatably supported with respect to the case 11 by, for example, a bearing member (not shown).

The power transmission device 10 to which the present invention can be applied is not limited to the front differential device, but may be a center differential device or a rear differential device. Alternatively, the power transmission device 10 may be a continuously variable transmission (CVT) including a pulley as a rotating member.

Lubricating oil for lubricating the power transmission device 10 is stored inside the case 11. In FIGS. 1 and 2, the oil level of the lubricating oil is indicated by the broken line O. The oil level O of the lubricating oil is set to a height at which at least the lower ends of the bearing members 23a and 23b are immersed in the lubricating oil in the non-operating state of the power transmission device 10. The lower part of the rotating member 20 is immersed in the lubricating oil, and when the rotating member 20 is rotated, the lubricating oil is scraped up by the rotating member 20. As a result, lubricating oil is supplied to the outer surface of the rotating member 20, and the contact portion between the rotating member 20 and other members is lubricated.

The baffle plate 30 covers the lower part of the rotating member 20 and reduces the stirring resistance of the lubricating oil applied to the rotating member 20. The baffle plate 30 according to the present embodiment constitutes a fan-shaped container as a whole, and can accommodate the lubricating oil scraped up by the rotation of the rotating member 20. The baffle plate 30 has shaft cylinder portions 33a and 33b extending on both sides of the rotation axis X of the rotation member 20. The cylinder portions 33a and 33b are rotatably supported with respect to the case 11 by the bearing members 35a and 35b. The baffle plate 30 and the rotating member 20 are independently and independently supported on the same rotation axis X so as to be rotatable about the axis.

<2. Baffle plate ＞
Hereinafter, the configuration of the baffle plate 30 provided in the power transmission device 10 according to the present embodiment will be described in detail. 3 and 4 are explanatory views showing the baffle plate 30. FIG. 3 is a perspective view of the baffle plate 30, and FIG. 4 is a plan view of the baffle plate 30 of FIG. 3 as viewed from above.

The baffle plate 30 according to the present embodiment corresponds to the plate member of the present invention. The baffle plate 30 includes fan-shaped side surface portions 31a and 31b arranged on both end faces of the rotating member 20, and peripheral surface portions 32 arranged on the outer peripheral portion of the rotating member 20 and connecting the two side surface portions 31a and 31b. , It has a shaft cylinder portion 33a, 33b extending further outward from the side surface portions 31a, 31b, respectively. The baffle plate 30 may be, for example, a molded body formed of a resin material, or may be a structure formed by joining metal plates.

The baffle plate 30 according to the present embodiment is configured as a fan-shaped container in which two side surface portions 31a and 31b are connected by an arcuate peripheral surface portion 32, but one or a plurality of openings are provided in the peripheral surface portion. May be provided.

The shaft tube portions 33a and 33b are portions supported by the bearing members 35a and 35b (see FIG. 2), and also function as a rotating shaft of the baffle plate 30. As a result, the baffle plate 30 is rotatably supported with respect to the case 11. At this time, the baffle plate 30 is supported by the bearing members 35a and 35b in a state where the rotational resistance is relatively small.

One end of the baffle plate 30 is provided with capacitance portions 34a and 34b having a larger plate thickness than the other portions. In the present embodiment, the capacitance portions 34a and 34b are provided at one end of the fan-shaped side surface portions 31a and 31b. The end portion provided with the capacitance portions 34a and 34b corresponds to the end portion on the tip end side along the rotation direction of the rotating member 20. The illustrated capacitance portions 34a and 34b have a circular planar shape, and are provided on the side surface portions 31a and 31b opposite to the surface facing the rotating member 20. The capacitance portions 34a and 34b may be integrally molded with the side surface portions 31a and 31b, and the capacitance portions 34a and 34b formed separately from the side surface portions 31a and 31b may be joined to the side surface portions 31a and 31b.

Since the capacitance portions 34a and 34b are provided at one end of the baffle plate 30, in the non-operating state of the power transmission device 10, the ends of the capacitance portions 34a and 34b provided by the weight of the capacitance portions 34a and 34b. The portion side moves downward, and at least a part of the capacitance portions 34a and 34b is immersed in the lubricating oil (see FIG. 1). As a result, the oil level O of the lubricating oil rises. The oil level O of the lubricating oil is set so that the lower ends of the bearing members 23a and 23b that support the rotating member 20 are at a height position where they are immersed in the lubricating oil while the capacitance portions 34a and 34b are immersed in the lubricating oil. Will be done.

FIG. 5 is an explanatory diagram showing a state in which the power transmission device 10 is operated and the rotating member 20 is rotationally driven. The rotating member 20 rotates in the counterclockwise direction shown in the figure. At this time, the lubricating oil in the baffle plate 30 is taken around by the rotating member 20, and the baffle plate 30 is dragged by the flow of the lubricating oil, so that the baffle plate 30 rotates in the counterclockwise direction. Then, the capacitance portions 34a and 34b provided at one end of the baffle plate 30 move above the oil level O of the lubricating oil, and the oil level O of the lubricating oil drops.

As a result, the amount of immersion of the rotating member 20 in the lubricating oil is reduced, and the drag torque of the lubricating oil applied to the rotating member 20 can be reduced. Therefore, the spin loss of the power transmission device 10 can be reduced. Even in this state, the lubricating oil is scraped up by the rotating member 20 and supplied to the sliding portions of the bearing members 23a and 23b, so that the lubricity of the sliding portions is ensured.

It is preferable that at least the specific gravity of the capacitance portions 34a and 34b is larger than the specific gravity of the lubricating oil. Since the specific gravity of the capacitance portions 34a and 34b is larger than the specific gravity of the lubricating oil, the capacitance portions 34a and 34b can be reliably moved downward and immersed in the lubricating oil in the non-rotating state of the rotating member 20. As a result, the oil level O of the lubricating oil rises, and at least the lower ends of the bearing members 23a and 23b can be immersed in the lubricating oil.

The larger the volume of the capacitance portions 34a and 34b, the greater the degree of decrease in the oil level O of the lubricating oil when the capacitance portions 34a and 34b move above the oil level O of the lubricating oil, and this is applied to the rotating member 20. The effect of reducing the drag torque of the lubricating oil can be increased. However, when the specific gravity of the capacitance portions 34a and 34b is relatively large, if the volume of the capacitance portions 34a and 34b is increased, the rotational resistance of the baffle plate 30 increases and the capacitance portions 34a and 34b are moved from the oil level O of the lubricating oil. It may be difficult to move it upward. Therefore, the volume of the capacitance portions 34a and 34b is the baffle plate 30 that is dragged and rotated by the drop of the oil level O of the lubricating oil that can be lowered and the lubricating oil that is rotated along with the rotation of the rotating member 20. It is preferable to set it appropriately in consideration of rotation resistance and the like.

The planar shape of the capacitance portions 34a and 34b is not limited to a circular shape, and may be a rectangular shape or another irregular shape. Further, in the present embodiment, the capacitance portions 34a and 34b are provided on the surface of the side surface portions 31a and 31b opposite to the surface facing the rotating member 20, but the positions where the capacitance portions 34a and 34b are provided are the same. Not limited to position. The capacitance portions 34a and 34b may be provided on the surface of the side surface portions 31a and 31b facing the rotating member 20, and may be provided on the outer surface or the inner surface of the peripheral surface portion 32.

However, when the capacitance portions 34a and 34b are provided on the surface of the side surface portions 31a and 31b or the peripheral surface portion 32 facing the rotating member 20, the distance between the capacitance portions 34a and 34b and the rotating member 20 becomes short. Spin loss may increase. Therefore, it is preferable that the capacitance portions 34a and 34b are provided on the surface of the side surface portions 31a and 31b or the peripheral surface portion 32 opposite to the surface facing the rotating member 20.

Further, the power transmission device 10 may include a stopper that defines the maximum displacement position of the baffle plate 30 that accompanies the rotation of the rotating member 20. With the rotation of the rotating member 20, the baffle plate 30 can lower the oil level O by rotating until the capacity portions 34a and 34b are located above the oil level O of the lubricating oil, and the capacity portion can be lowered. Even if 34a and 34b move further upward, the effect of lowering the oil level O is not affected. On the other hand, when the drag of the lubricating oil is large under some conditions such as low temperature conditions where the viscosity of the lubricating oil is high, the baffle plate 30 rotates once with the rotation of the rotating member 20, and the capacitance portions 34a and 34b May return to its original position. Therefore, by defining the maximum displacement position of the baffle plate 30, the oil level O can be stably lowered during the rotation of the rotating member 20.

FIG. 6 is an explanatory diagram showing a configuration example for defining the maximum displacement position of the baffle plate 30. In the example shown in FIG. 6, one end of the baffle plate 30 provided with the capacitance portions 34a and 34b is provided with an overhanging portion 37 protruding outward from the peripheral surface portion 32 of the baffle plate 30. Further, the case 11 is provided with a stopper portion 13 at a position where the overhanging portion 37 of the baffle plate 30 can come into contact with the case 11. Therefore, when the baffle plate 30 rotates with the rotation of the rotating member 20, the overhanging portion 37 of the baffle plate 30 comes into contact with the stopper portion 13 of the case 11, and the baffle plate 30 further rotates. Be restricted.

At the maximum displacement position of the baffle plate 30 in which the overhanging portion 37 abuts on the stopper portion 13, the capacitance portions 34a and 34b are positioned above the oil level O of the lubricating oil. Therefore, in the rotating state of the rotating member 20, the amount of immersion of the rotating member 20 in the lubricating oil is reduced, and the drag torque of the lubricating oil applied to the rotating member 20 can be reduced. On the other hand, since the baffle plate 30 does not rotate once and the capacitance portions 34a and 34b do not return to their original positions, the oil level O can be stably lowered during the rotation of the rotating member 20.

The configuration example of the stopper for defining the maximum displacement position of the baffle plate 30 is not limited to the example shown in FIG. A stopper with which a part of the baffle plate 30 that rotates with the rotation of the rotating member 20 abuts may be provided in a part of the case 11 or inside the case 11.

As described above, in the power transmission device 10 according to the present embodiment, the capacity portions 34a and 34b are provided in a part of the baffle plate 30, and are dragged by the lubricating oil that is carried along with the rotation of the rotating member 20. It is provided with a baffle plate 30 that rotates around the surface. The capacitance portions 34a and 34b of the baffle plate 30 are immersed in the lubricating oil when the rotating member 20 is not rotating, and are located above the oil level O of the lubricating oil due to the rotation of the baffle plate 30 when the rotating member 20 is rotated. It has become like.

Therefore, when the rotating member 20 is not rotating or is rotating at an extremely low speed, the oil level O rises due to the immersion of the capacitance portions 34a and 34b, and at least the lower ends of the bearing members 23a and 23b that support the rotating member 20 are pressed. It can be immersed in lubricating oil. On the other hand, when the rotating member 20 is rotated, the volume portions 34a and 34b are located above the oil level O of the lubricating oil, so that the volume integral oil level O of the volume portions 34a and 34b is lowered to the lubricating oil. The amount of immersion of the rotating member 20 can be reduced. As a result, the stirring resistance of the lubricating oil applied to the rotating member 20 is reduced, and the spin loss of the power transmission device 10 can be reduced.

Further, in the power transmission device 10 according to the present embodiment, the baffle plate 30 is provided with capacitance portions 34a and 34b, and the baffle plate 30 is configured to be axially rotatable on the same axis as the rotating member 20. Therefore, it is possible to reduce the spin loss of the power transmission device 10 while ensuring the lubricity of the bearing members 23a and 23b of the rotating member 20 without significantly increasing the number of parts or requiring electrical control. can. Further, since the baffle plate 30 can rotate coaxially with the rotating member 20, the drag torque of the lubricating oil can be suppressed to a relatively small value.

Further, in the power transmission device 10 according to the present embodiment, the capacitance portions 34a and 34b are provided on the surface of the baffle plate 30 opposite to the surface facing the rotating member 20. Therefore, it is possible to suppress an increase in stirring resistance due to the capacitance portions 34a and 34b getting too close to the rotating member 20.

Further, in the power transmission device 10 according to the present embodiment, at least the specific gravity of the capacitance portions 34a and 34b may be larger than the specific gravity of the lubricating oil. As a result, when the rotating member 20 is not rotated, the capacitance portions 34a and 34b are immersed in the lubricating oil due to the weight of the capacitance portions 34a and 34b, and the oil level O of the lubricating oil can be reliably raised.

Although the preferred embodiments of the present invention have been described in detail with reference to the accompanying drawings, the present invention is not limited to these examples. It is clear that a person having ordinary knowledge in the field of technology to which the present invention belongs can come up with various modifications or modifications within the scope of the technical ideas described in the claims. , These are also naturally understood to belong to the technical scope of the present invention.

For example, in the above embodiment, the plate member provided with the capacitance portion is a baffle plate, but the present invention is not limited to such an example. In addition to the baffle plate, the power transmission device may include a plate member that can be displaced with the rotation of the rotating member, and the plate member may be provided with a capacitance portion. Even with such a power transmission device, when the rotating member is not rotating, the capacitance portion is immersed in the lubricating oil and the oil level rises, while when the rotating member rotates, the capacitance portion moves upward from the oil level of the lubricating oil and the oil level is increased. Can be reduced. Therefore, it is possible to reduce the spin loss of the power transmission device while ensuring the lubricity of the bearing member of the rotating member.

Further, in the above embodiment, the baffle plate provided with the capacitance portion is configured to be rotatable coaxially with the rotating member, but the present invention is not limited to this example. For example, a capacitance portion may be provided on the plate member that can move up and down with the rotation of the rotating member 20. Even with such a power transmission device, when the rotating member is not rotating, the capacitance portion is immersed in the lubricating oil and the oil level rises, while when the rotating member rotates, the capacitance portion moves upward from the oil level of the lubricating oil and the oil level is increased. Can be reduced.

10 Power transmission device 11 Case 13 Stopper part 20 Rotating member 23a, 23b Bearing member 30 Baffle plate 31a, 31b Side surface part 32 Peripheral surface part 34a, 34b Capacity part 35a, 35b Bearing member 37 Overhanging part

Claims (7)

Cases where lubricating oil is stored and
A rotating member whose lower portion is immersed in the lubricating oil and housed in the case so as to be rotatable around the axis.
A plate member arranged with a gap interposed therebetween, at least between the rotating member and the lower axial end face thereof, is provided.
A capacity portion having a plate thickness larger than that of the other portion is provided in a part of the plate member.
The plate member can be displaced with the rotation of the rotating member, and the plate member can be displaced.
The capacitance portion is immersed in the lubricating oil when the rotating member is not rotated, and the lubrication is caused by the flow of the lubricating oil generated by the rotation of the rotating member and the rotation along the rotation direction of the rotating member. A power transmission device located above the oil level. The power transmission device according to claim 1 , wherein the plate member is axially rotatable on the same axis as the rotating member. The power transmission device according to claim 1 or 2 , wherein the capacitance portion is provided on the tip end side in the rotation direction of the plate member. The power transmission device according to any one of claims 1 to 3 , wherein the capacitance portion is provided on a surface of the plate member opposite to the surface facing the rotating member. The power transmission device according to any one of claims 1 to 4 , wherein the specific gravity of the capacitance portion is larger than the specific gravity of the lubricating oil. The power transmission device according to any one of claims 1 to 5 , further comprising a stopper that defines a maximum displacement position of the plate member. The power transmission device according to any one of claims 1 to 6 , wherein the plate member is a baffle plate.

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