JP7024635B2 - Vehicle power transmission device - Google Patents

Description

The present invention belongs to the technical field relating to a power transmission device for a vehicle provided with a cylindrical drum that transmits power in the rotational direction.

Generally, an automatic transmission mounted on a vehicle such as an automobile is provided with a friction fastening element (brake or clutch). This friction fastening element has a cylindrical drum (brake drum or clutch drum) that transmits power in the rotational direction. A plurality of friction plates are attached to the drum, and the friction fastening elements are fastened by engaging these friction plates with, for example, a plurality of friction plates attached to a clutch hub.

A plurality of holes may be formed on the peripheral side wall of the drum as described above. For example, in Patent Document 1, in a power transmission device including a transmission, a support member that rotatably supports a counter drive gear to which power from the transmission is transmitted connects a rotating element of the transmission to a transmission case. It is disclosed that it has a cylindrical drum portion that functions as a brake drum of a friction fastening element that makes it non-rotatable, and that a plurality of holes are formed in the drum portion.

Japanese Unexamined Patent Publication No. 2016-70330

Since the drum of the friction fastening element as described above has a relatively large diameter and is heavy, there is a problem that the inertia is large, and as a result, the shift time becomes long. Further, since the automatic transmission is usually provided with a plurality of friction fastening elements, there is a problem that the weight of the entire automatic transmission increases and the fuel efficiency of the vehicle deteriorates. Especially in the case of FR vehicles, the drum of the friction fastening element tends to be long in the axial direction, and it is strongly required to reduce the weight and inertia of the drum.

Therefore, it is conceivable to reduce the weight and inertia of the drum by forming a hole in the peripheral side wall of the drum as in Patent Document 1.

However, there is a limit to the weight reduction and low inertia of the drum only by forming a hole in the peripheral side wall of the drum, and a drastic improvement is desired.

The present invention has been made in view of such a point, and an object thereof is in a power transmission device for a vehicle provided with a cylindrical drum for transmitting power in the rotational direction, such as an automatic transmission. The purpose is to make the drum significantly lighter and less inertial.

In order to achieve the above object, the present invention is intended for a vehicle power transmission device provided with a cylindrical drum that transmits power in the rotational direction, and the drums are separated from each other in the axial direction of the drum. The power input to the first annular portion or the second annular portion is applied between the first annular portion and the second annular portion located at the locations, and between the first annular portion and the second annular portion. It has a power transmission unit for transmission, and the power transmission unit is composed of a plurality of rod-shaped connecting members arranged around the central axis of the drum and connecting the first annular portion and the second annular portion. In the plurality of rod-shaped connecting members, all the rod-shaped connecting members extend from the first annular portion side in the axial direction toward the second annular portion side in an inclined manner toward the same side in the circumferential direction of the drum. In the middle of the axial direction in the power transmission unit , there is an annular intermediate member that suppresses the radial outward displacement of the plurality of rod-shaped connecting members when the drum is rotated. The drum is provided so as to extend in the entire circumferential direction, and when the power is transmitted by the power transmission unit, torque acts on the first annular portion in one direction in the circumferential direction and the first annular portion is always subjected to the torque. Torque is applied to the two annular portions in the other direction in the circumferential direction, and all of the plurality of rod-shaped connecting members are directed from the first annular portion side in the axial direction to the second annular portion side. The configuration is such that it is inclined and extends in the same direction as the direction of the torque acting on the first annular portion in the circumferential direction .

With the above configuration, the power transmission unit between the first annular portion and the second annular portion of the drum is composed of a plurality of rod-shaped connecting members. Therefore, by reducing the number of rod-shaped connecting members as much as possible, the number of rod-shaped connecting members can be reduced as much as possible. It is possible to significantly reduce the weight and inertia of the drum.

Here, when the drum is rotated, the rod-shaped connecting member is displaced outward in the radial direction by the centrifugal force, and due to this displacement, the rod-shaped connecting member is displaced to the end on the first annular portion side or the end on the second annular portion side. There is a possibility of damage at the part. However, since the displacement is suppressed by the annular intermediate member, it is possible to prevent the rod-shaped connecting member from being damaged by centrifugal force.

Further, by appropriately setting the inclination direction of the plurality of rod-shaped connecting members according to the direction of the torque acting on the first annular portion and the second annular portion when the power is transmitted by the power transmission unit, the torque is applied. It is possible to effectively prevent damage to the rod-shaped connecting member.

Therefore, it is possible to significantly reduce the weight and inertia of the drum while reliably transmitting the power by the power transmission unit.

Further, the number of rod-shaped connecting members can be further reduced while effectively preventing damage to the rod-shaped connecting members due to the torque acting on the first annular portion and the second annular portion.

In the vehicle power transmission device, it is preferable that the intermediate member is integrally formed with the plurality of rod-shaped connecting members.

As a result, the number of parts can be reduced and intermediate members can be easily provided .

In one embodiment or another embodiment, the rod-shaped connecting members are connected to the facing surfaces of the first annular portion and the second annular portion facing each other in the axial direction, respectively. A corner portion between the surface of the rod-shaped connecting member on one side and the other side in the circumferential direction where the angle formed with the facing surface of the first annular portion is an acute angle and the facing surface of the first annular portion. And / or, of the surfaces on one side and the other side in the circumferential direction of each rod-shaped connecting member, the surface on the side where the angle formed with the facing surface of the second annular portion is an acute angle and the facing surface of the second annular portion. It is preferable that a reinforcing portion is provided at a corner portion between the surface and the surface.

As a result, the torque acting on the first annular portion and the second annular portion reinforces the portion where the rod-shaped connecting member is likely to be damaged (the portion where stress concentration is likely to occur), and the torque causes the rod-shaped connecting member to be further damaged. It can be prevented more effectively.

As described above, according to the vehicle power transmission device of the present invention, the drum can be significantly reduced in weight and inertia while reliably transmitting power by the power transmission unit.

It is a skeleton diagram which shows an example of the automatic transmission as a power transmission device for a vehicle which concerns on embodiment of this invention. It is a fastening table which shows the fastening state of the friction fastening element at each shift stage of the automatic transmission. It is sectional drawing which shows the clutch drum of the 2nd clutch and the 3rd clutch in the state which is mounted on the said automatic transmission. It is a perspective view which shows the drum which concerns on Embodiment 1. FIG. It is a figure which looked at the drum of FIG. 4 from the outside in the radial direction. It is a figure corresponding to FIG. 4 which shows the drum which concerns on Embodiment 2. FIG. It is a figure corresponding to FIG. 5 of the drum of FIG. It is a figure corresponding to FIG. 4 which shows the drum which concerns on Embodiment 3.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 shows an example of an automatic transmission 1 as a power transmission device for a vehicle according to an embodiment of the present invention. The automatic transmission 1 is a vertical automatic transmission mounted on an FR type vehicle.

The automatic transmission 1 includes a transmission case 11, an input shaft 12 inserted into the transmission case 11 and to which power from a drive source (engine, motor, etc.) of the vehicle is input, and inside the transmission case 11. A transmission mechanism 14 accommodated in the transmission and transmitting power from the drive source via the input shaft 12, and an output shaft 13 inserted in the transmission case 11 and outputting power from the transmission mechanism 14 to the propeller shaft. have.

The input shaft 12 and the output shaft 13 are arranged coaxially along the front-rear direction of the vehicle, and the input shaft 12 is located on the front side of the vehicle and the output shaft is in a state where the automatic transmission 1 is mounted on the vehicle. 13 is located on the rear side of the vehicle. In the following description, the drive source side (the left side of FIG. 1 and the front side of the vehicle) in the axial direction of the input shaft 12 (the axial direction of the output shaft 13) is referred to as the front side, and the axial direction of the input shaft 12 The side opposite to the drive source in FIG. 1 (on the right side in FIG. 1 and on the rear side of the vehicle) is referred to as the rear side.

The transmission mechanism 14 has a first planetary gear set PG1 (hereinafter referred to as a first gear set PG1), a second planetary gear set PG2 (hereinafter referred to as a second gear set PG2), and a third planetary gear set PG3 (hereinafter referred to as a first gear set PG1) arranged in the axial direction of the input shaft 12. Hereinafter, it has a third gear set PG3) and a fourth planetary gear set PG4 (hereinafter referred to as a fourth gear set PG4). The first gear set PG1, the second gear set PG2, the third gear set PG3, and the fourth gear set PG4 are arranged in this order from the front side to form a plurality of power transmission paths from the input shaft 12 to the output gear 13. The first to fourth gear sets PG1 to PG4 are arranged on the same axis as the input shaft 12 and the output shaft 13.

The first gear set PG1 has a first sun gear S1, a first ring gear R1 and a first carrier C1 as rotating elements. The first gear set PG1 is a single pinion type, and a plurality of pinions P1 supported by the first carrier C1 and arranged at intervals in the circumferential direction of the first gear set PG1 are the first sun gear S1 and the first ring gear. It is meshed with both of R1.

The second gear set PG2 has a second sun gear S2, a second ring gear R2, and a second carrier C2 as rotating elements. The second gear set PG2 is also a single pinion type, and a plurality of pinions P2 supported by the second carrier C2 and arranged at intervals in the circumferential direction of the second gear set PG2 are the second sun gear S2 and the second ring gear. It is meshed with both of R2.

The third gear set PG3 has a third sun gear S3, a third ring gear R3, and a third carrier C3 as rotating elements. The third gear set PG3 is also a single pinion type, and a plurality of pinions P3 supported by the third carrier C3 and arranged at intervals in the circumferential direction of the third gear set PG3 are the third sun gear S3 and the third ring gear. It is meshed with both of R3.

The fourth gear set PG4 has a fourth sun gear S4, a fourth ring gear R4, and a fourth carrier C4 as rotating elements. The fourth gear set PG4 is also a single pinion type, and a plurality of pinions P4 supported by the fourth carrier C4 and arranged at intervals in the circumferential direction of the fourth gear set PG4 are the fourth sun gear S4 and the fourth ring gear. It is meshed with both of R4.

The first sun gear S1 of the first gear set PG1 is divided into two in the axial direction of the input shaft 12, and is arranged on the rear side relative to the front side first sun gear S1a arranged on the relatively front side. It has one sun gear S1b. That is, the first gear set PG1 is a double sun gear type gear set. Since the front and rear first sun gears S1a and S1b have teeth having the same number of teeth and mesh with the pinion P1 supported by the first carrier C1, these front and rear first sun gears S1a and S1b The number of revolutions of is always equal. That is, the front and rear first sun gears S1a and S1b always rotate at the same rotation speed, and when the rotation of one gear is stopped, the rotation of the other gear is also stopped.

The first sun gear S1 (strictly speaking, the rear first sun gear S1b) and the fourth sun gear S4 are always connected, the first ring gear R1 and the second sun gear S2 are always connected, and the second carrier C2 and the fourth carrier are always connected. C4 is always connected, and the third carrier C3 and the fourth ring gear R4 are always connected. Further, the input shaft 12 is always connected to the first carrier C1, and the output shaft 13 is always connected to the fourth carrier C4. Specifically, the input shaft 12 is connected to the first carrier C1 via a power transmission member 18 passing between the front and rear first sun gears S1a and S1b. The rear first sun gear S1b and the fourth sun gear S4 are connected via a power transmission shaft 15. The second carrier C2 and the fourth carrier C4 are connected via a power transmission member 16.

The speed change mechanism 14 also has five friction fastening elements (first clutch) for selecting one from the plurality of power transmission paths formed by the first to fourth gear sets PG1 to PG4 and switching the power transmission path. 20, the second clutch 21, the third clutch 22, the first brake 23 and the second brake 24).

The first clutch 20 is configured to connect and disconnect the input shaft 12 and the first carrier C1 and the third sun gear S3. The first clutch 20 is arranged on the front side of the first gear set PG1.

The second clutch 21 is configured to connect and disconnect the first ring gear R1 and the second sun gear S2 and the third sun gear S3. The second clutch 21 is arranged on the front side of the first clutch 20.

The third clutch 22 is configured to connect and disconnect the second ring gear R2 and the third sun gear S3. The third clutch 22 is arranged on the front side of the second clutch 21.

The third sun gear S3 and all of the first clutch 20, the second clutch 21, and the third clutch 22 are connected via the connecting member 5 and the connecting member 8, and the first ring gear R1 and the second sun gear S2 and the second are connected. The clutch 21 is connected via the clutch drum 6 of the second clutch 21, and the second ring gear R2 and the third clutch 22 are connected via the clutch drum 7 of the third clutch 22.

The first brake 23 is configured to connect and disconnect the first sun gear S1 (strictly speaking, the front first sun gear S1a) and the transmission case 11. The first brake 23 is arranged in the vicinity of the transmission case 11 on the front side of the third clutch 22. When the first brake 23 is fastened, the first sun gear S1 is fixed to the transmission case 11.

The second brake 24 is configured to connect and disconnect the third ring gear R3 and the transmission case 11. The second brake 24 is arranged in the vicinity of the transmission case 11 on the front side of the third gear set PG3. When the second brake 24 is fastened, the third ring gear R3 is fixed to the transmission case 11.

Each of the friction fastening elements is fastened by supplying hydraulic oil to the fastening hydraulic chamber of each friction fastening element. As shown in the fastening table of FIG. 2, by selectively fastening three friction fastening elements from the five friction fastening elements, forward 1st to 8th speeds and backward speeds are formed. In the fastening table of FIG. 2, a circle indicates that the friction fastening element is fastened, and a blank indicates that the friction fastening element has released (released) the fastening.

Specifically, the first speed is formed by engaging the first clutch 20, the first brake 23, and the second brake 24. The second speed is formed by engaging the second clutch 21, the first brake 23, and the second brake 24. By engaging the first clutch 20, the second clutch 21, and the second brake 24, the third speed is formed. By engaging the second clutch 21, the third clutch 22, and the second brake 24, the fourth speed is formed. By engaging the first clutch 20, the third clutch 22, and the second brake 24, the fifth speed is formed. The sixth speed is formed by engaging the first clutch 20, the second clutch 21, and the third clutch 22. By engaging the first clutch 20, the third clutch 22, and the first brake 23, the seventh speed is formed. The eighth speed is formed by engaging the second clutch 21, the third clutch 22, and the first brake 23. A retreat speed is formed by engaging the third clutch 22, the first brake 23, and the second brake 24. In the 6th speed, the rotation speed of the input shaft 12 and the rotation speed of the output shaft 13 are the same.

FIG. 3 specifically shows the clutch drums 6 and 7 mounted on the automatic transmission 1. In FIG. 3, C is the central axis of the input shaft 12 (the central axis of the output shaft 13) and coincides with the central axes of the clutch drums 6 and 7 (the central axis L in the drum 30 described later). The axial direction of the clutch drums 6 and 7 coincides with the axial direction of the input shaft 12 (the axial direction of the output shaft 13).

The clutch drum 6 is the clutch drum of the second clutch 21, and is located inside the connecting member 5 in the radial direction. The clutch drum 6 is formed in a bottomed cylindrical shape that is open to the front side and has a rear end portion as a bottom. The clutch drum 6 is connected to the first ring gear R1 of the first gear set PG1 at the rear end portion (bottom portion). A plurality of friction plates 51 are attached to the inner peripheral surface of the front end portion of the peripheral side wall of the clutch drum 6. These friction plates 51 engage with a plurality of friction plates 52 attached so as to be alternately aligned with the friction plates 51 in the connecting member 8 when the second clutch 21 is engaged. When the second clutch 21 is in the engaged state, the clutch drum 6 transmits power in the rotational direction from the first ring gear R1 to the third sun gear S3.

The clutch drum 7 is the clutch drum of the third clutch 22, and is located on the radial inside of the connecting member 5 and on the radial outside of the clutch drum 6. Like the clutch drum 6, the clutch drum 7 is also formed in a bottomed cylindrical shape that is open to the front side and has a rear end portion as a bottom. The clutch drum 7 is connected to the second ring gear R2 of the second gear set PG2 at the rear end portion (bottom portion). A plurality of friction plates 53 are attached to the inner peripheral surface of the front end portion of the peripheral side wall of the clutch drum 7. These friction plates 53 engage with a plurality of friction plates 54 attached so as to be alternately aligned with the friction plates 53 in the connecting member 8 when the third clutch 22 is engaged. The clutch drum 7 transmits power in the rotational direction from the second ring gear R2 to the third sun gear S3 when the third clutch 22 is in the engaged state.

Hereinafter, the detailed configuration of the clutch drum 6 and the clutch drum 7 will be described with reference to the drum 30 (having the same shape as the clutch drum 6) according to the first embodiment shown in FIGS. 4 and 5. This configuration of the drum 30 is applied to the clutch drum 6 and the clutch drum 7. In the following description of the drum 30, "front" and "rear" are the same as "front" and "rear" when the drum 30 is mounted on the automatic transmission 1 as the clutch drum 6 and the clutch drum 7, respectively. be.

(Embodiment 1)
4 and 5 show the drum 30 according to the first embodiment. In the present embodiment, the drum 30 has a first annular portion 31 and a second annular portion 32 located at two positions apart from each other in the axial direction (hereinafter referred to as the drum axial direction) of the drum 30. In the present embodiment, the first annular portion 31 is the front end portion and its vicinity on the peripheral side wall of the drum 30, and the second annular portion 32 is the vicinity of the rear end portion (bottom portion) on the peripheral side wall of the drum 30. It is a part.

The front portion of the first annular portion 31 is a spline portion 31a. In the present embodiment, since the first annular portion 31 has a thin plate shape, the ridges and concave portions extending in the drum axial direction are drums on both the inner peripheral surface and the outer peripheral surface of the first annular portion 31. They are arranged alternately in the circumferential direction of 30 (hereinafter referred to as the drum circumferential direction). However, on the outer peripheral surface of the first annular portion 31, the concave portion is located at the portion corresponding to the ridge portion on the inner peripheral surface, and the ridge portion is located at the portion corresponding to the concave portion on the inner peripheral surface. A plurality of friction plates 51 are spline-fitted on the inner peripheral surface side of the spline portion 31a of the first annular portion 31.

The outer diameter of the front end portion of the second annular portion 32 is substantially the same as the outer diameter of the rear end portion of the first annular portion 31. The outer diameter of the portion of the second annular portion 32 excluding the front end portion is made smaller than the outer diameter of the front end portion.

The drum 30 further includes a power transmission unit 35 that transmits power in the rotational direction input to the first annular portion 31 or the second annular portion 32 between the first annular portion 31 and the second annular portion 32. Have. In the present embodiment, the power transmission unit 35 transmits the power transmitted to the second annular portion 32 from the second annular portion 32 to the first annular portion 31.

The power transmission unit 35 is composed of a plurality of (eight in this embodiment) rod-shaped connecting members 36 arranged around the central axis L of the drum 30 and connecting the first annular portion 31 and the second annular portion 32. Has been done. In the present embodiment, the plurality of rod-shaped connecting members 36 have substantially the same outer diameter as the outer diameter of the rear end portion of the first annular portion 31 (that is, substantially the same outer diameter as the outer diameter of the front end portion of the second annular portion 32). On a virtual cylindrical surface having a diameter), they are arranged at intervals in the circumferential direction of the drum. At both ends of each rod-shaped connecting member 36, facing surfaces of the first annular portion 31 and the second annular portion 32 facing each other in the drum axial direction (that is, the rear end surfaces and the second annular portion 31 of the first annular portion 31). It is connected to the front end surface of the annular portion 32). As described above, since the power transmission unit 35 is composed of a plurality of rod-shaped connecting members 36, the drum 30 is significantly reduced as compared with the case where the power transmission unit 35 is an annular portion such as the second annular portion 32. It is possible to reduce the weight and inertia.

In the present embodiment, each rod-shaped connecting member 36 has a rectangular cross section, and the thickness direction of each rod-shaped connecting member 36 is the radial direction of the drum 30. The thickness of each rod-shaped connecting member 36 is the same as the thickness of the rear end portion of the first annular portion 31 and the front end portion of the second annular portion 32 (thickness of the peripheral side wall of the drum 30). Each rod-shaped connecting member 36 is integrally formed with the first annular portion 31 and the second annular portion 32.

Each rod-shaped connecting member 36 is in a twisted position with respect to the central axis L of the drum 30. That is, each rod-shaped connecting member 36 extends inclined from the first annular portion 31 side in the drum axial direction toward the second annular portion 32 side toward one side or the other side in the drum circumferential direction. In the present embodiment, all the rod-shaped connecting members 36 are inclined from the first annular portion 31 side in the drum axial direction to the second annular portion 32 side toward the same side in the drum circumferential direction. That is, the plurality of rod-shaped connecting members 36 are provided in the first form. In the present embodiment, when the power is transmitted by the power transmission unit 35, the torque T1 acts on the first annular portion 31 in one direction in the circumferential direction of the drum and the torque T1 acts on the second annular portion 32 as shown in FIG. Torque T2 (the size is the same as T1) acts on the other side of the drum circumferential direction. Correspondingly, all the rod-shaped connecting members 36 act on the first annular portion 31 in the circumferential direction of the drum from the first annular portion 31 side in the drum axial direction to the second annular portion 32 side. It extends at an angle to the same side as the direction (counterclockwise when viewed from the rear side of the drum 30).

Due to the torques T1 and T2, a rotational moment is generated in each rod-shaped connecting member 36, and the rod-shaped connecting member 36 extending in an inclined manner is twisted (rotated) in a direction parallel to the central axis L of the drum 30. ). Since the length of the rod-shaped connecting member 36 is larger than the distance between the first annular portion 31 and the second annular portion 32 in the drum axial direction by the amount of inclination, the rod-shaped connecting member 36 has torque T1 and 1. By T2, the first annular portion 31 and the second annular portion 32 are stretched and compressed. As a result, the rod-shaped connecting member 36 has a torque T1 and T2 as compared with the case where the inclination direction of the rod-shaped connecting member 36 is opposite to that of the present embodiment (when the rod-shaped connecting member 36 is pulled by the torques T1 and T2). On the other hand, it is strong and hard to break.

The number of rod-shaped connecting members 36 is preferably as small as possible in consideration of the magnitude of the torques T1 and T2 and the strength of the rod-shaped connecting members 36.

In the present embodiment, of the surfaces on one side and the other side in the drum circumferential direction of each rod-shaped connecting member 36, the side formed by the facing surface (rear side end surface) of the first annular portion 31 has an acute angle (direction of torque T1). A corner R portion 41 as a reinforcing portion for reinforcing the corner portion is provided at a corner portion between the surface of the first annular portion 31 and the facing surface of the first annular portion 31. By setting the radius of curvature of the corner R portion 41 to a predetermined value or more, the corner portion is reinforced. Similarly, of the surfaces on one side and the other side in the drum circumferential direction of each rod-shaped connecting member 36, the side where the angle formed with the facing surface of the second annular portion 32 is an acute angle (the same side as the direction of the torque T2). A corner R portion 42 as a reinforcing portion is also provided at a corner portion between the surface and the facing surface (front end surface) of the second annular portion 32. The radius of curvature of the corner R portion 42 is also set to a predetermined value (which may be the same as or different from the predetermined value regarding the radius of curvature of the corner R portion 41) or more. That is, the corners R portions 41 and 42 reinforce the portions of the rod-shaped connecting member 36 that are particularly prone to breakage (where stress concentration is likely to occur) due to the torques T1 and T2 acting on the first annular portion 31 and the second annular portion 32. Will be done.

The corners R portions 41 and 42 are not always necessary and may not be necessary. Alternatively, only one of the two corners R portions 41 and 42 may be provided.

Further, the reinforcing portion may be formed of, for example, a reinforcing member instead of the corner R portion 41 (42). This reinforcing member is rod-shaped connected to the first annular portion 31 (second annular portion 32) so as to cover the portion before the corner R portion 41 (42) from the radial outside or inside of the drum 30. It will be connected to the member 36.

In the middle of the power transmission unit 35 in the drum axial direction (that is, between the first annular portion 31 and the second annular portion 32), a plurality of rod-shaped connecting members 36 are radially outside the drum 30 when the drum 30 is rotated. An annular intermediate member 37 that suppresses displacement to the drum is provided so as to extend in the entire circumferential direction of the drum. In the present embodiment, the intermediate member 37 is provided at the center of the power transmission unit 35 in the drum axial direction (the center between the first annular portion 31 and the second annular portion 32). The intermediate member 37 also has a rectangular cross section, and the thickness direction of the intermediate member 37 is the radial direction of the drum 30. The thickness of the intermediate member 37 is the same as the thickness of each rod-shaped connecting member 36. The intermediate member 37 is integrally formed with a plurality of rod-shaped connecting members 36. In this embodiment, each rod-shaped connecting member 36 and the intermediate member 37 intersect at a plane.

In the present embodiment, of the surfaces on one side and the other side in the drum circumferential direction of each rod-shaped connecting member 36, the angle formed with the front surface (the surface on the first annular portion 31 side) of the intermediate member 37 is an acute angle. A corner R portion 43 is also provided at a corner portion between the surface and the front surface of the intermediate member 37 to reinforce the corner portion. Further, among the surfaces on one side and the other side in the drum circumferential direction of each rod-shaped connecting member 36, the surface on the side where the angle formed with the rear surface (the surface on the second annular portion 32 side) of the intermediate member 37 is an acute angle. A corner R portion 44 is also provided at a corner portion between the intermediate member 37 and the rear surface thereof to reinforce the corner portion. These corners R portions 43 and 44 may not be provided.

Here, when the intermediate member 37 is not provided, the rod-shaped connecting member 36 is displaced outward in the radial direction of the drum due to centrifugal force when the drum 30 is rotated, and the rod-shaped connecting member 36 is displaced to the first annular portion 31 side by this displacement. There is a possibility of damage at the end or the end on the second annular portion 32 side. Alternatively, in the present embodiment, since the first annular portion 31 has a thin plate shape, the spline portion 31a of the first annular portion 31 extends in the circumferential direction of the drum due to the above displacement (height of the ridge portion and the height of the ridge portion). There is a possibility that it will expand in the radial direction of the drum (while the depth of the recess becomes smaller).

However, in the present embodiment, since the displacement is suppressed by the annular intermediate member 37, it is possible to prevent the rod-shaped connecting member 36 from being damaged by the centrifugal force. Further, it is possible to prevent the spline portion 31a of the first annular portion 31 from expanding in the drum radial direction while extending in the drum circumferential direction.

Further, since the plurality of rod-shaped connecting members 36 are inclined and extended and are configured to be stretched between the first annular portion 31 and the second annular portion 32 by the torques T1 and T2, the torques T1 and T1 It is possible to effectively prevent the rod-shaped connecting member 36 from being damaged by T2.

Therefore, in the present embodiment, the drum 30 can be significantly reduced in weight and inertia while reliably transmitting power by the power transmission unit 35.

In the present embodiment, the power transmission unit 35 transmits the power transmitted to the second annular portion 32 from the second annular portion 32 to the first annular portion 31, but from the first annular portion 31 to the second annular portion 31. Power may be transmitted to 32. When the power is transmitted in this case, the direction of the torque acting on the first annular portion 31 and the second annular portion 32 is the same as when the power is transmitted from the second annular portion 32 to the first annular portion 31. For example, the configuration of the drum 30 of the present embodiment can be adopted. Further, power may be transmitted only from the first annular portion 31 to the second annular portion 32, and in this case as well, the configuration of the drum 30 of the present embodiment can be adopted, and the first annular portion 31 and the second annular portion 31 and the second annular portion 32 can be adopted. The direction of inclination of the rod-shaped connecting member 36 may be set according to the direction of the torque acting on the annular portion 32. In the second and third embodiments described later, even when the power is transmitted from the second annular portion 32 to the first annular portion 31, the power is transmitted from the first annular portion 31 to the second annular portion 32. However, there is no restriction on the direction of the torque acting on the first annular portion 31 and the second annular portion 32.

(Embodiment 2)
6 and 7 show the drum 30 according to the second embodiment (the same parts as those in FIGS. 4 and 5 are designated by the same reference numerals, and detailed description thereof will be omitted), and the configuration of the power transmission unit 35 is configured. Unlike the first embodiment, the rod-shaped connecting member 36 is prevented from being damaged by the torque regardless of the direction of the torque acting on the first annular portion 31 and the second annular portion 32. ..

The configuration of the drum 30 according to the present embodiment can be applied to the clutch drum 6 and the clutch drum 7, but the state of action of torque on the first annular portion 31 and the second annular portion 32 will be described later. Since it is preferable to apply it to the drum of a vehicle power transmission device having a drum that may be in the state of 1 or the second state described later, it is applied to the drum here ( The same applies to the drum 30 according to the third embodiment described later). The "front" and "rear" of the drum 30 according to the present embodiment are the same as the "front" and "rear" of the drum 30 according to the first embodiment (also the drum 30 according to the third embodiment described later). Similarly).

That is, in the present embodiment, unlike the first embodiment, when the power is transmitted by the power transmission unit 35, the torque T1 acts on the first annular portion 31 in one direction in the circumferential direction of the drum and the second annular portion 31. The first state in which the torque T2 (= T1) acts on the portion 32 in the other direction in the circumferential direction of the drum, and the first state opposite to the first annular portion 31 and the second annular portion 32, respectively. There is a second state in which torques T1'and T2'(T1'= T2') act in the direction of.

A part of the rod-shaped connecting members 36 among the plurality of (here, 16) rod-shaped connecting members 36 is the third in the drum axial direction so as to correspond to both the first state and the second state. The first rod-shaped connecting member 36A extending inclining from the one annular portion 31 side toward the second annular portion 32 side toward one side in the drum circumferential direction (the same side as the rod-shaped connecting member of the first embodiment), and the rest. The rod-shaped connecting member 36 of the above is inclined from the first annular portion 31 side in the drum axial direction to the second annular portion 32 side toward the other side in the drum circumferential direction (the side opposite to the rod-shaped connecting member of the first embodiment). It is a second rod-shaped connecting member 36B that extends. That is, the plurality of rod-shaped connecting members 36 are provided in the second form. In the present embodiment, a plurality of the first rod-shaped connecting member 36A and the second rod-shaped connecting member 36B are provided, and the numbers are the same (8 each).

When the magnitudes of the torques T1'and T2'in the second state are different from the magnitudes of the torques T1 and T2 in the first state, the number of the first rod-shaped connecting members 36A and the second The number of rod-shaped connecting members 36B may be different from each other. One of the first rod-shaped connecting member 36A and the second rod-shaped connecting member 36B may be one.

In the present embodiment, the plurality of first rod-shaped connecting members 36A are spaced apart in the drum circumferential direction on the same virtual cylindrical surface as in the first embodiment, similarly to the rod-shaped connecting member 36 of the first embodiment. The plurality of second rod-shaped connecting members 36B are also arranged on the virtual cylindrical surface at intervals in the circumferential direction of the drum. Each second rod-shaped connecting member 36B is flat with one first rod-shaped connecting member 36A in the middle of the power transmission unit 35 in the drum axial direction (in the present embodiment, the center of the power transmission unit 35 in the drum axial direction). Cross. Further, in the first annular portion 31, the direction of the torque T1 with respect to the first rod-shaped connecting member 36A that intersects the second rod-shaped connecting member 36B in a plane at the portion where each second rod-shaped connecting member 36B is connected. The first rod-shaped connecting member 36A adjacent to the same side is connected. Further, in the second annular portion 32, the direction of the torque T2 with respect to the first rod-shaped connecting member 36A that intersects the second rod-shaped connecting member 36B in a plane at the portion where each second rod-shaped connecting member 36B is connected. The first rod-shaped connecting member 36A adjacent to the same side is connected.

Also in the present embodiment, similarly to the first embodiment, a plurality of rod-shaped connecting members 36 (first rod-shaped connecting member 36A and the first rod-shaped connecting member 36A) are located in the middle (center) of the power transmission unit 35 in the drum axial direction when the drum 30 is rotated. An annular intermediate member 37 is provided to prevent the second rod-shaped connecting member 36B) from being displaced outward in the radial direction of the drum 30. The intermediate member 37 is integrally formed with a plurality of rod-shaped connecting members 36, and is a portion where the first rod-shaped connecting member 36A and the second rod-shaped connecting member 36B intersect in a plane, and the first rod-shaped connecting member It intersects 36A and the second rod-shaped connecting member 36B in a plane. As a result, the first rod-shaped connecting member 36A, the second rod-shaped connecting member 36B, and the intermediate member 37 form a truss structure.

The angle formed by the facing surface of the first annular portion 31 of the surfaces on one side and the other side in the drum circumferential direction of each rod-shaped connecting member 36 (each first rod-shaped connecting member 36A and each second rod-shaped connecting member 36B) is The corner portion between the surface on the acute-angled side and the facing surface of the first annular portion 31, and the second annular portion 32 of the surfaces on one side and the other side in the drum circumferential direction of each rod-shaped connecting member 36. Similar to the first embodiment, the corners R portions 41 and 42 are provided at the corners between the surface on the side where the angle formed with the facing surface is an acute angle and the facing surface of the second annular portion 32, respectively. There is.

Further, between the surface of each rod-shaped connecting member 36 on one side and the other side in the circumferential direction of the drum where the angle formed with the front surface of the intermediate member 37 is an acute angle and the surface on the front side of the intermediate member 37. And the surface of each rod-shaped connecting member on one side and the other side in the drum circumferential direction where the angle formed with the rear surface of the intermediate member 37 is an acute angle and the rear side of the intermediate member 37. Corners R portions 43 and 44 are also provided at the corners between the surfaces.

In the present embodiment, regardless of whether the torque acting state on the first annular portion 31 and the second annular portion 32 is the first state or the second state, the first annular portion 31 and the second annular portion 31 and the second annular portion. It is possible to effectively prevent the rod-shaped connecting member 36 (the first rod-shaped connecting member 36A and the second rod-shaped connecting member 36B) from being damaged by the torque acting on the 32. Further, similarly to the first embodiment, the intermediate member 37 can prevent the rod-shaped connecting member 36 from being damaged by the centrifugal force.

Further, in the present embodiment, since the first rod-shaped connecting member 36A, the second rod-shaped connecting member 36B and the intermediate member 37 form a truss structure, they act on the first annular portion 31 and the second annular portion 32. The damage of the rod-shaped connecting member 36 due to the torque applied and the damage of the rod-shaped connecting member 36 due to the centrifugal force are less likely to occur, and the number of the first rod-shaped connecting member 36A and the second rod-shaped connecting member 36B is reduced by that amount. You will be able to.

(Embodiment 3)
FIG. 8 shows the drum 30 according to the third embodiment (the same parts as those in FIG. 6 are designated by the same reference numerals, and detailed description thereof will be omitted), and the first rod-shaped connecting member 36A and the second rod-shaped connecting member 36A are shown. The arrangement of the member 36B in the drum circumferential direction is different from that of the second embodiment.

That is, in the present embodiment, the first rod-shaped connecting member 36A and the second rod-shaped connecting member 36B are provided as in the second embodiment, but the first rod-shaped connecting member 36A and the second rod-shaped connecting member 36A are provided. The number of connecting members 36B is smaller than that of the second embodiment, and the number of connecting members 36B is four each. Further, the first rod-shaped connecting member 36A and the second rod-shaped connecting member 36B do not intersect in a plane between the first annular portion 31 and the second annular portion 32. That is, the first rod-shaped connecting member 36A and the second rod-shaped connecting member 36B are alternately provided in the drum circumferential direction. Other configurations are the same as those in the second embodiment.

In the present embodiment, although the truss structure is not as in the second embodiment, the torque acting state on the first annular portion 31 and the second annular portion 32 is the first, as in the second embodiment. The rod-shaped connecting member 36 (first rod-shaped connecting member 36A and second rod-shaped connecting member 36B) due to the torque acting on the first annular portion 31 and the second annular portion 32 regardless of the state or the second state. ) Can be effectively prevented from being damaged. Further, the intermediate member 37 can prevent the rod-shaped connecting member 36 from being damaged by centrifugal force.

The present invention is not limited to the above embodiment, and can be substituted as long as it does not deviate from the gist of the claims.

For example, in the above embodiment, the configuration of the drum 30 (particularly the drum 30 according to the first embodiment) is applied to the clutch drum 6 of the second clutch 21 and the clutch drum 7 of the third clutch 22 in the automatic transmission 1. As shown, the configuration of the drum 30 can be applied to any drum as long as it is a cylindrical drum that transmits power in the rotational direction, including a drum (brake drum or clutch drum) of a friction fastening element. can. For example, the connecting member 5 of the automatic transmission 1 is also composed of a drum, and the axial length of the drum is longer than that of the clutch drums 6 and 7, so that the drum (connecting member 5) can be made lighter and less inertial. Therefore, the configuration of the drum 30 may be applied to the drum. Further, the configuration of the drum 30 can be applied to the drum of the power transmission device for a vehicle other than the automatic transmission 1.

The above embodiments are merely examples, and the scope of the present invention should not be construed in a limited manner. The scope of the present invention is defined by the scope of the claims, and all modifications and modifications belonging to the equivalent scope of the claims are within the scope of the present invention.

INDUSTRIAL APPLICABILITY The present invention is useful for a vehicle power transmission device provided with a cylindrical drum for transmitting power in the rotational direction, and particularly useful for an automatic transmission equipped with a clutch drum and / or a brake drum having a large diameter and weight. be.

1 Automatic transmission (power transmission device for vehicles)
6 Clutch drum of the 2nd clutch 7 Clutch drum of the 3rd clutch 30 Drum 31 1st annular part 32 2nd annular part 35 Power transmission part 36 Rod-shaped connecting member 37 Intermediate member 41 Corner R part (reinforcing part)
42 Corner R part (reinforcing part)

Claims (3)

A power transmission device for vehicles equipped with a cylindrical drum that transmits power in the direction of rotation.
The drum has the first annular portion and the second annular portion located at two positions apart from each other in the axial direction of the drum, and the first annular portion and the second annular portion between the first annular portion and the second annular portion. It has a power transmission unit for transmitting the above-mentioned power input to the unit or the second annular portion, and has a power transmission unit.
The power transmission unit is composed of a plurality of rod-shaped connecting members arranged around the central axis of the drum and connecting the first annular portion and the second annular portion.
The plurality of rod-shaped connecting members are
All the rod-shaped connecting members are provided in the first form in which the rod-shaped connecting member is inclined and extends from the first annular portion side in the axial direction toward the second annular portion side in the same side in the circumferential direction of the drum.
In the middle of the power transmission unit in the axial direction, an annular intermediate member that suppresses the displacement of the plurality of rod-shaped connecting members to the outside in the radial direction when the drum is rotated is formed in the entire circumferential direction of the drum. It is provided so as to extend to
When the power is transmitted by the power transmission unit, torque acts on the first annular portion in one direction in the circumferential direction and torque acts on the second annular portion in the other direction in the circumferential direction. Is supposed to
All of the plurality of rod-shaped connecting members are inclined from the first annular portion side in the axial direction toward the second annular portion side in the circumferential direction toward the same side as the direction of the torque acting on the first annular portion. A power transmission device for vehicles, which is characterized by being extended . In the vehicle power transmission device according to claim 1,
The intermediate member is a power transmission device for a vehicle, characterized in that it is integrally formed with the plurality of rod-shaped connecting members. In the vehicle power transmission device according to claim 1 or 2 .
Each of the rod-shaped connecting members is connected to the facing surfaces of the first annular portion and the second annular portion facing each other in the axial direction.
Of the surfaces on one side and the other side of each rod-shaped connecting member in the circumferential direction, the surface on the side where the angle formed with the facing surface of the first annular portion is an acute angle is between the facing surface of the first annular portion. The corner portion and / or the surface of each of the rod-shaped connecting members on one side and the other side in the circumferential direction where the angle formed with the facing surface of the second annular portion is an acute angle and the second annular portion. A power transmission device for a vehicle, characterized in that a reinforcing portion is provided at an acute angle between the facing surfaces of the vehicle.

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