JP2013002522A - Driving force transmission apparatus - Google Patents

Abstract

An object of the present invention is to reduce drag torque between clutch plates when a clutch having a high relative rotational difference is released.
A dry multi-plate clutch that connects and disconnects transmission of driving force is provided. In this hybrid driving force transmission device, the dry multi-plate clutch 7 includes a drive plate 71 that is spline-fitted to the clutch hub 3, a driven plate 72 that is spline-fitted to the clutch drum 6, and an airflow diverting radiation groove 791. . The airflow diverting radiating groove 791 is provided on the plate surface of the driven plate 72, and the direction of the centrifugal airflow E generated in the outer diameter direction by the plate rotation is determined in the axial direction (axial airflow H at the position between adjacent clutch plates. ).
[Selection] Figure 8

Description

  The present invention relates to a driving force transmission device that is applied to a vehicle driving system and includes a dry multi-plate clutch that connects and disconnects transmission of driving force.

  Conventionally, as a multi-plate clutch, the tooth portion of the clutch plate is divided into a plurality of divided pieces in the circumferential direction, and the divided pieces of the same phase of adjacent clutch plates protrude toward each other, One in which the divided pieces protrude alternately in the axial direction is known (for example, see Patent Document 1).

  In this conventional multi-plate clutch, a clearance between adjacent clutch plates is maintained by applying a divided piece of a tooth portion to prevent dragging of the clutch plate when the clutch is released.

JP 2009-216159 A

  However, in the conventional multi-plate clutch, a part of the clutch plate (a divided piece of the tooth portion) is in contact when the clutch is released. For this reason, the generation of drag torque cannot be avoided, and the drag torque increases as the relative rotational difference between the clutch plates increases.

  In the case of a multi-plate clutch applied to a driving force transmission device, if drag torque is increased, fuel consumption is deteriorated. Also, heat is generated by dragging at the contact portion of the clutch plate, leading to a reduction in the life of the multi-plate clutch. In other words, the higher the relative rotation difference, the larger the energy loss. Therefore, it is particularly important to reduce the drag torque at the high relative rotation difference in order to suppress the energy loss.

  The present invention has been made paying attention to the above problems, and an object of the present invention is to provide a driving force transmission device capable of reducing drag torque between clutch plates when a clutch having a high relative rotational difference is released. .

In order to achieve the above object, in the present invention, in a driving force transmission device including a dry multi-plate clutch that connects and disconnects transmission of driving force,
The dry multi-plate clutch is a means including a first clutch plate, a second clutch plate, and an airflow turning structure.
The first clutch plate is splined to the clutch hub.
The second clutch plate is splined to the clutch drum.
The airflow diverting structure is provided on a plate surface of at least one of the first clutch plate and the second clutch plate, and the direction of the centrifugal airflow generated in the outer diameter direction by rotating the plate is set to the adjacent clutch. Change axially between the plates.

As described above, the plate surface of the dry multi-plate clutch has an airflow diverting structure that changes the direction of the centrifugal airflow generated in the outer diameter direction by rotating the plate in the axial direction at the position between adjacent clutch plates.
Therefore, when the clutch is released, a centrifugal air flow is generated in which air moves in the outer diameter direction due to the centrifugal pressure effect caused by the plate rotation. This centrifugal airflow tends to flow between adjacent clutch plates in the outer diameter direction, but the direction is changed in the axial direction at an intermediate position by the airflow diverting structure to become an axial airflow. With the airflow pressure of the axial airflow whose direction is changed, the adjacent clutch plates are separated, and the plates are kept apart.
In this way, by controlling the direction of the centrifugal air flow, a plate separation state is realized as if an air spring is interposed between adjacent clutch plates, and drag torque caused by partial contact or full contact of adjacent clutch plates. Is reduced.
The centrifugal air flow in which air moves in the outer diameter direction has a larger flow rate as the relative rotational difference between the first clutch plate and the second clutch plate is higher. For this reason, the airflow pressure of the centrifugal airflow whose direction is changed in the axial direction by the airflow diverting structure increases as the relative rotational difference increases, ensuring a stronger plate pulling action when the clutch with a higher relative rotational difference is released. Is done.
As a result, the drag torque between the clutch plates can be reduced when the clutch having a high relative rotational difference is released.

1 is an overall schematic diagram showing a hybrid driving force transmission device (an example of a driving force transmission device) of Example 1. FIG. It is principal part sectional drawing which shows the structure of the motor & clutch unit in the hybrid driving force transmission apparatus of Example 1. FIG. It is a disassembled side view which shows the piston assembly of the dry multi-plate clutch in the hybrid driving force transmission device of Example 1. It is a disassembled perspective view which shows the piston assembly of the dry multi-plate clutch in the hybrid driving force transmission device of Example 1. It is a front view which shows the drive plate of the dry multi-plate clutch in the hybrid drive force transmission device of Example 1. They are the AA sectional view (a) and the front view (b) which show the driven plate of the dry multi-plate clutch in the hybrid driving force transmission apparatus of Example 1. FIG. FIG. 3 is an operation explanatory diagram illustrating an abrasion powder discharging operation in the hybrid driving force transmission device according to the first embodiment. It is an effect explanatory view showing the direction control action of centrifugal air current at the time of clutch release of the hybrid driving force transmission device of Example 1. It is an effect explanatory view showing drag torque reduction effect at the time of clutch release of the hybrid driving force transmission device of Example 1. It is a figure which shows the structure of the driven plate of the dry multi-plate clutch in the hybrid driving force transmission apparatus of Example 2, and the direction control effect | action of centrifugal airflow. It is a figure which shows the structure of the driven plate of the dry multi-plate clutch in the hybrid driving force transmission apparatus of Example 3, and the direction control effect | action of centrifugal airflow. It is a figure which shows the structure of the driven plate of the dry type multi-plate clutch in the hybrid drive force transmission device of Example 4, and the direction control action / wear powder discharge action of centrifugal airflow.

  Hereinafter, the best mode for realizing the driving force transmission device of the present invention will be described based on Examples 1 to 4 shown in the drawings.

First, the configuration will be described.
The configuration of the hybrid driving force transmission device according to the first embodiment will be described by being divided into “overall configuration”, “configuration of motor & clutch unit”, and “plate arrangement configuration of dry multi-plate clutch”.

[overall structure]
FIG. 1 is an overall schematic diagram illustrating a hybrid driving force transmission device (an example of a driving force transmission device) according to a first embodiment. Hereinafter, the overall configuration of the hybrid driving force transmission device will be described with reference to FIG.

  As shown in FIG. 1, the hybrid driving force transmission device of the first embodiment includes an engine Eng, a motor & clutch unit M / C, a transmission unit T / M, an engine output shaft 1, a clutch hub shaft 2, The clutch hub 3, the clutch drum shaft 4, the transmission input shaft 5, the clutch drum 6, the dry multi-plate clutch 7, the slave cylinder 8, and the motor / generator 9 are provided. The slave cylinder 8 that hydraulically controls engagement / release of the dry multi-plate clutch 7 is generally called “CSC” (concentric slave cylinder).

  The hybrid driving force transmission device of the first embodiment connects the motor / generator 9 and the transmission input shaft 5 via the clutch drum 6 and the clutch drum shaft 4 when the dry multi-plate clutch 7 that is normally open is opened. “Electric vehicle travel mode”. Then, when the dry multi-plate clutch 7 is hydraulically engaged by the slave cylinder 8, the engine Eng and the motor / generator 9 are connected, and the engine output shaft 1 and the clutch hub shaft 2 are connected via the damper 21. Then, the clutch hub 3 and the clutch drum 6 are connected via the fastened dry multi-plate clutch 7 to set the “hybrid vehicle travel mode”.

  The motor & clutch unit M / C includes a dry multi-plate clutch 7, a slave cylinder 8, and a motor / generator 9. The dry multi-plate clutch 7 is connected to the engine Eng to connect and disconnect the driving force transmitted from the engine Eng. The slave cylinder 8 hydraulically controls engagement / release of the dry multi-plate clutch 7. The motor / generator 9 is disposed at the outer peripheral position of the clutch drum 6 of the dry multi-plate clutch 7 and transmits power to the transmission input shaft 5. The motor & clutch unit M / C is provided with a cylinder housing 81 having a first clutch pressure oil passage 85 to the slave cylinder 8 while maintaining the sealing performance by the O-ring 10.

  The motor / generator 9 is a synchronous AC motor, and includes a rotor support frame 91 provided integrally with the clutch drum 6, and a rotor 92 supported and fixed to the rotor support frame 91 and embedded with permanent magnets. The rotor 92 includes a stator 94 that is disposed via the air gap 93 and is fixed to the cylinder housing 81, and a stator coil 95 that is wound around the stator 94. The cylinder housing 81 is formed with a water jacket 96 for circulating cooling water.

  The transmission unit T / M is connected to the motor & clutch unit M / C and includes a transmission housing 41, a V-belt continuously variable transmission mechanism 42, and an oil pump O / P. The V-belt type continuously variable transmission mechanism 42 is built in the transmission housing 41, spans a V-belt between two pulleys, and changes the belt contact diameter to obtain a continuously variable transmission ratio. The oil pump O / P is a hydraulic pressure source that produces the hydraulic pressure to the necessary part. The oil pump pressure is used as the original pressure, and the oil pressure from the control valve (not shown) that regulates the shift hydraulic pressure, clutch / brake hydraulic pressure, etc. to the pulley chamber. Guide the hydraulic pressure to the required part. The transmission unit T / M is further provided with a forward / reverse switching mechanism 43, an oil tank 44, and an end plate 45. The end plate 45 has a second clutch pressure oil passage 47 (FIG. 2).

  The oil pump O / P drives the pump by transmitting the rotational drive torque of the transmission input shaft 5 via a chain drive mechanism. The chain drive mechanism includes a drive-side sprocket 51 that rotates as the transmission input shaft 5 rotates, a driven-side sprocket 52 that rotates the pump shaft 57, and a chain 53 that spans both the sprockets 51 and 52. Have. The drive-side sprocket 51 is interposed between the transmission input shaft 5 and the end plate 45, and is rotatably supported via a bush 55 with respect to a stator shaft 54 fixed to the transmission housing 41. Then, the rotational input torque from the transmission input shaft 5 is transmitted through the first adapter 56 that is engaged with the transmission input shaft 5 by spline fitting and the driving sprocket 51.

[Configuration of motor & clutch unit]
FIG. 2 is a cross-sectional view of a main part illustrating the configuration of the motor and clutch unit in the hybrid driving force transmission device according to the first embodiment. 3 and 4 are views showing a piston assembly of the dry multi-plate clutch 7. FIG. Hereinafter, the configuration of the motor and clutch unit M / C will be described with reference to FIGS.

  The clutch hub 3 is connected to the engine output shaft 1 of the engine Eng. As shown in FIG. 2, a drive plate 71 (first clutch plate) of the dry multi-plate clutch 7 is held on the clutch hub 3 so as to be movable in the axial direction by spline fitting.

  The clutch drum 6 is connected to the transmission input shaft 5 of the transmission unit T / M. As shown in FIG. 2, a driven plate 72 (second clutch plate) of the dry multi-plate clutch 7 is held on the clutch drum 6 so as to be movable in the axial direction by spline fitting.

  The dry-type multi-plate clutch 7 is interposed between the clutch hub 3 and the clutch drum 6 by alternately arranging a plurality of drive plates 71 and driven plates 72 with friction facings 73 and 73 attached on both sides. Be dressed. That is, when the dry multi-plate clutch 7 is fastened, torque can be transmitted between the clutch hub 3 and the clutch drum 6, and by opening the dry multi-plate clutch 7, between the clutch hub 3 and the clutch drum 6. Shut off torque transmission.

  The slave cylinder 8 is a hydraulic actuator that controls the engagement and release of the dry multi-plate clutch 7, and is disposed at a position between the transmission unit T / M side and the clutch drum 6. As shown in FIG. 2, the slave cylinder 8 has a piston 82 slidably provided in the cylinder hole 80 of the cylinder housing 81 and a clutch pressure formed by the transmission housing unit T / M. A first clutch pressure oil passage 85 that leads and a cylinder oil chamber 86 that communicates with the first clutch pressure oil passage 85 are provided. As shown in FIG. 2, a needle bearing 87, a piston arm 83, a return spring 84, and an arm press-fitting plate 88 are interposed between the piston 82 and the dry multi-plate clutch 7.

  The piston arm 83 generates a pressing force of the dry multi-plate clutch 7 by a pressing force from the slave cylinder 8, and is slidably provided in a through hole 61 formed in the clutch drum 6. The return spring 84 is interposed between the piston arm 83 and the clutch drum 6. The needle bearing 87 is interposed between the piston 82 and the piston arm 83, and suppresses the piston 82 from being rotated with the rotation of the piston arm 83. The arm press-fitting plate 88 is provided integrally with the bellows elastic support members 89 and 89, and the inner peripheral portion and the outer peripheral portion of the bellows elastic support members 89 and 89 are press-fitted and fixed to the clutch drum 6. The arm press-fit plate 88 and the bellows elastic support members 89 and 89 block leakage oil from the piston arm 83 from flowing into the dry multi-plate clutch 7. In other words, the arm press-fit plate 88 and the bellows elastic support member 89 hermetically sealed at the piston arm mounting position of the clutch drum 6 divide the wet space in which the slave cylinder 8 is arranged from the dry space in which the dry multi-plate clutch 7 is arranged. It has a function.

  As shown in FIGS. 3 and 4, the piston arm 83 includes an arm body 83a formed in a ring shape, and arm protrusions 83b protruding from the arm body 83a at four locations.

  As shown in FIGS. 3 and 4, the return spring 84 includes a spring support plate 84a formed in a ring shape and a plurality of coil springs 84b fixed to the spring support plate 84a.

  The arm press-fitting plate 88 is press-fitted and fixed to the arm protrusion 83b of the piston arm 83, as shown in FIG. As shown in FIGS. 3 and 4, bellows elastic support members 89 and 89 are integrally provided on the inner side and the outer side of the arm press-fitting plate 88.

  As shown in FIG. 2, the leak oil recovery oil passage of the first embodiment includes a first bearing 12, a first seal member 31, a leak oil passage 32, a first recovery oil passage 33, and a second recovery oil passage. 34. In other words, the leak oil from the sliding portion of the piston 82 passes through the first recovery oil passage 33 and the second recovery oil passage 34 sealed by the first seal member 31 and returns to the transmission unit T / M. is there. In addition to this, the leak oil passage 32 in which leak oil from the sliding portion of the piston arm 83 is sealed by a partition elastic member (arm press-fit plate 88, bellows elastic support members 89, 89), and the first seal member 31. This is a circuit that passes through the first recovery oil passage 33 and the second recovery oil passage 34 that are sealed with each other and returns to the transmission unit T / M.

  As shown in FIG. 2, the bearing lubricating oil passage of the first embodiment includes a needle bearing 20, a second seal member 14, a first axial oil passage 19, a second axial oil passage 18, and a lubricating oil passage. 16 and a gap 17. The bearing lubricating oil path includes a bearing lubricant from the transmission unit T / M, a needle bearing 20, a first bearing 12 that rotatably supports the clutch drum 6 with respect to the cylinder housing 81, a piston 82, and a piston arm. The bearing is lubricated by a path that passes through the needle bearing 87 interposed between the two and 83 and returns to the transmission unit T / M.

  As shown in FIG. 2, the second seal member 14 is interposed between the clutch hub 3 and the clutch drum 6. The second seal member 14 seals the bearing lubricant from flowing from the wet space in which the slave cylinder 8 is disposed into the dry space in which the dry multi-plate clutch 7 is disposed.

[Plate layout of dry multi-plate clutch]
FIG. 5 shows the drive plate 71 of the dry multi-plate clutch 7 in the hybrid driving force transmission device of the first embodiment, and FIG. 6 shows the driven plate 72 of the dry multi-plate clutch 7 in the hybrid driving force transmission device of the first embodiment. Show. Hereinafter, the plate arrangement configuration of the dry multi-plate clutch 7 will be described with reference to FIGS. 2, 5, and 6.

  The dry multi-plate clutch 7 according to the first embodiment is a clutch for connecting and disconnecting transmission of driving force from the engine Eng. As shown in FIG. 2, the dry multi-plate clutch 7 has a closed space surrounded by the clutch hub 3, the clutch cover 6, and the housing cover 60. Arranged in the clutch chamber 64.

  The housing cover 60 is integrally fixed to the cylinder housing 81 and covers the motor / generator 9 and the dry multi-plate clutch 7. Of the internal space formed by covering the housing cover 60 and the cylinder housing 81, the space on the clutch rotating shaft CL (= rotor shaft) side is defined as a clutch chamber 64 that houses the dry multi-plate clutch 7, and the clutch chamber 64 The outer space is a motor chamber 65 that houses the motor / generator 9. The clutch chamber 64 and the motor chamber 65 divided by the dust seal member 62 are dry spaces that block oil from entering. The cylinder housing 81 is a stationary member that is supported by the first bearing 12 with respect to the clutch drum shaft 4, and the housing cover 60 is supported by the second bearing 13 with respect to the clutch hub shaft 2 and the cover seal 15. It is the stationary member sealed by.

  As shown in FIG. 2, the dry multi-plate clutch 7 includes a drive plate 71, a driven plate 72, a friction facing 73, and a housing cover 60.

  The drive plate 71 is spline-fitted to the clutch hub 3 and has a vent hole 74 through which the airflow flowing in the axial direction passes through the spline-fitting portion with the clutch hub 3. As shown in FIG. 5, the drive plate 71 is a position of a spline tooth projecting portion 75 projecting to the inner diameter side among spline teeth meshing with the spline portion of the clutch hub 3, and is formed on the friction facing 73. A ventilation hole 74 is provided at an inner position of the facing groove 76. As shown in FIG. 2, the drive plate 71 is set so that a plurality of (four in the first embodiment) vent holes 74 communicate in the axial direction.

  The friction facings 73 are provided on both surfaces of the drive plate 71, and the friction surface presses against the plate surface of the driven plate 72 when the clutch is engaged. As shown in FIG. 5, the friction facing 73 is an annular plate member, and has a facing groove 76 formed by a radial radial straight line from the inner diameter position toward the outer diameter position. The facing groove 76 has a depth that maintains the shape of the concave groove even if the facing wear proceeds to some extent.

  As shown in FIG. 2, the housing cover 60 includes an outside air suction hole 66 for taking outside air into the clutch chamber 64 defined by the closed space, and an outside air discharge hole 67 for discharging airflow from the clutch chamber 64 defined by the closed space to the outside air. Have.

  As shown in FIG. 2, the outside air suction hole 66 corresponds to the axial position of the ventilation hole 74, and is provided at an inner diameter side position for taking in outside air toward the ventilation hole 74.

  As shown in FIG. 2, the outside air discharge hole 67 is located at an outer diameter side position for discharging the airflow moving through the spline fitting portion of the driven plate 72 to the outside air while suppressing the flow toward the outside air suction hole 66 by the labyrinth structure. Have.

  The labyrinth structure will be described. On the clutch drum 6 side, the tip end portion is extended in the axial direction to form the axial tip portion 6a. On the other hand, on the housing cover 60 side, an inner wall recess 60a is formed at a position where the axial front end portion 6a of the clutch drum 6 enters, and an inner wall protrusion 60b is formed at a radially outer position than the inner wall recess 60a. The labyrinth structure is configured to suppress the flow toward the outside air suction hole 66 by setting the outside air discharge hole 67 at a position radially outside the clutch drum 6 and at a position radially inside the dust seal member 62.

The driven plate 72 is spline-fitted to the clutch drum 6 and has a vent opening 77 through which the airflow flowing in the axial direction passes through the spline fitting portion with the clutch drum 6. As shown in FIG. 6, the ventilation opening 77 is set by a space that is formed when a concave portion 78 is formed at the center position of the spline tooth protrusion projecting to the outer diameter side and is connected to the spline tooth of the clutch drum 6. is doing.
On the plate surface of the driven plate 72, an airflow diverting radiation groove that changes the direction of the centrifugal airflow generated in the outer diameter direction by rotating the plate in the axial direction at a position between the adjacent drive plate 71 and the driven plate 72. 791 (airflow diverting structure) is provided. As shown in FIG. 6 (b), the airflow diverting radiating groove 791 opens an inner peripheral end 791a into which the centrifugal airflow flows in the outer diameter direction, and an outer peripheral end 791b that changes the direction of the centrifugal airflow in the axial direction. The shape of the radiation groove is closed by the surface. As the airflow diverting radiating groove 791, four grooves are provided on the surface of the driven plate 72 at intervals of 90 degrees, and at the positions on the back surface of the driven plate 72 that are shifted from the grooves on the surface by 45 degrees at intervals of 90 degrees. Four grooves are provided. Note that the driven plate 72 disposed at both ends of the dry multi-plate clutch 7 may be provided with the airflow diverting radiation groove 791 only on one side facing the drive plate 71.

Next, the operation will be described.
The operation of the hybrid driving force transmission device of the first embodiment is divided into “clutch engagement / release operation by slave cylinder”, “wear powder discharge operation of dry multi-plate clutch”, and “pulling torque reduction operation when clutch is released”. To do.

[Clutch engagement / release action by slave cylinder]
In the case of the hybrid driving force transmission device, the dry multi-plate clutch 7 is engaged when the mode is changed from the “electric vehicle traveling mode” to the “hybrid vehicle traveling mode”. Then, when the mode transition is made from the “hybrid vehicle travel mode” to the “electric vehicle travel mode”, the dry multi-plate clutch 7 is released. Hereinafter, a clutch fastening / releasing action for fastening / releasing the dry multi-plate clutch 7 by the slave cylinder 8 will be described with reference to FIG.

  When the open multi-plate clutch 7 is engaged, the clutch hydraulic pressure produced by the transmission unit T / M is supplied to the cylinder oil chamber 86 through the first clutch pressure oil passage 85 formed in the cylinder housing 81. To do. As a result, the hydraulic pressure obtained by multiplying the hydraulic pressure and the pressure receiving area acts on the piston 82, and the piston 82 is pressed against the urging force of the return spring 84 interposed between the piston arm 83 and the clutch drum 6. Stroke to the right. Then, the fastening force due to the difference between the oil pressure and the urging force is transmitted from the piston 82 → the needle bearing 87 → the piston arm 83 → the arm press-fitting plate 88, pressing the drive plate 71 and the driven plate 72, and the dry multi-plate clutch 7 It is concluded.

  When the dry multi-plate clutch 7 in the engaged state is released, the hydraulic oil supplied to the cylinder oil chamber 86 passes through the clutch pressure oil passage 85 to the transmission unit T / M and acts on the piston 82. When the oil pressure is lowered, the urging force of the return spring 84 exceeds the oil pressure, and the piston arm 83 and the arm press-fit plate 88 that are integrally formed are stroked in the left direction in FIG. As a result, the fastening force transmitted to the arm press-fitting plate 88 is released, and the dry multi-plate clutch 7 is released.

[Abrasive powder discharging action of dry multi-plate clutch]
In the hybrid driving force transmission device provided with the dry multi-plate clutch 7, if wear powder accumulates between the drive plate 71 and the driven plate 72, it causes plate dragging and clutch engagement / release failure. Therefore, it is necessary to discharge the wear powder from between the plates 71 and 72. Hereinafter, based on FIG. 7, the abrasion powder discharge | emission effect | action of the dry-type multi-plate clutch 7 reflecting this is demonstrated.

  The friction facing 73 of the drive plate 71 of the dry multi-plate clutch 7 of the first embodiment has facing grooves 76 radially. For this reason, when at least one of the clutch hub 3 and the clutch drum 6 rotates around the clutch rotation axis CL, a centrifugal fan effect using the clutch hub 3 having the friction facings 73 on both sides as blades occurs.

  Due to this centrifugal fan effect, as shown in FIG. 7, air is sent from the B region on the clutch hub 3 side to the C region on the clutch drum 6 side in the outer diameter direction, the pressure on the clutch drum 6 side increases, and the clutch hub 3 The pressure on the side decreases. Due to this pressure difference, a centrifugal airflow E is generated in which air moves in the outer diameter direction from the clutch hub 3 side to the clutch drum 6 side.

  Due to the generation of the centrifugal air flow E, the pressure on the clutch hub 3 side is lowered, so that a pressure difference is generated with the outside air having a high pressure. Therefore, as shown in FIG. 7, the outside air taken in from the outside air suction hole 66 passes through each ventilation hole 74 and generates an inner diameter side axial airflow F that flows into the clutch hub 3 side where the atmospheric pressure is lowered.

  Further, the spline fitting portion of the driven plate 72 has a low airflow resistance by having a clearance margin in order to ensure plate movement. In addition, since the spline fitting portion between the driven plate 72 and the clutch drum 6 has a ventilation opening 77 through which an airflow flowing in the axial direction passes, the ventilation resistance is further reduced. Then, since the atmospheric pressure on the clutch drum 6 side is increased due to the generation of the centrifugal airflow E, an atmospheric pressure difference is generated with the outside air. Therefore, as shown in FIG. 7, the airflow that has changed the direction from the inner diameter side axial direction to the outer diameter direction and has flowed into the clutch drum 6 side passes through the outside air discharge hole 67 from the vent opening 77 of the spline fitting portion. An outer-diameter axial airflow G that is discharged to the outside air is generated.

  As shown by the arrow in FIG. 7, an air flow (F → E → G) is generated by the air flow generating action, which draws a flow line of outside air → inner diameter side axial direction → radial direction → outer diameter side axial direction → outside air. The Here, FIG. 7 shows only the centrifugal airflow E on the most piston side, but a plurality of centrifugal airflows E are generated at the locations having the facing grooves 76. For this reason, the abrasion powder peeled off from the surface of the friction facing 73 due to repeated clutch connection / disconnection moves on the airflow (F → E → G) and is discharged to the outside.

As described above, the dry multi-plate clutch 7 according to the first embodiment has the outside air suction hole 66, the outside air discharge hole 67, and the drive plate 71 so as to generate an air flow (F → E → G) due to a pressure difference. And a vent hole 74 through which an airflow flowing in the axial direction is passed (FIG. 7).
Therefore, dragging due to wear powder between the drive plate 71 and the driven plate 72 is suppressed, and the dry multi-plate clutch 7 is prevented from being poorly engaged / released.

The drive plate 71 according to the first embodiment employs a configuration in which, among the spline teeth that mesh with the spline portion of the clutch hub 3, a vent hole 74 is provided at the position of the spline tooth protrusion 75 that protrudes toward the inner diameter side (FIG. 5).
Therefore, as compared with the case where a hole is formed in the spline tooth recess, a large opening area of the vent hole 74 is ensured, so that an inner diameter side axial airflow F is generated by an orderly flow.

The friction facing 73 according to the first embodiment has a facing groove 76 formed in the outer diameter direction from the inner diameter position toward the outer diameter position, and the drive plate 71 has a configuration having a vent hole 74 at an inner position of the facing groove 76. Adopted (Figure 5).
Therefore, the airflow resistance when the airflow exiting the airflow hole 74 flows into the facing groove 76 is kept low, and the direction change of the airflow from the inner diameter side axial airflow F to the centrifugal airflow E is performed smoothly.

The driven plate 72 according to the first embodiment employs a configuration in which a spline fitting portion with the clutch drum 6 has a ventilation opening 77 through which an airflow flowing in the axial direction passes (FIG. 6).
Therefore, the airflow resistance generated when the airflow from the facing groove 76 flows along the spline fitting portion with the clutch drum 6 is suppressed to a low level, so that the outer diameter side axial airflow G is generated by an orderly flow.

The housing cover 60 of the first embodiment corresponds to the axial position of the vent hole 74 and has an outside air suction hole 66 at an inner diameter side position for taking in outside air toward the vent hole 74. And the structure which has the outside air discharge hole 67 in the outer-diameter side position which discharges | emits the airflow which moves the spline fitting part of the driven plate 72 to outside air by suppressing the flow which goes to the outside air suction hole 66 with a labyrinth structure (FIG. 5).
Therefore, the flow of the airflow that attempts to circulate in the clutch chamber 64 is suppressed by the labyrinth structure, so that the flow of the airflow that draws a streamline of outside air → inner diameter side axial direction → radial direction → outer diameter side axial direction → outside air is orderly. Generated.

[Drag torque reduction when the clutch is released]
In the hybrid driving force transmission device including the dry multi-plate clutch 7, drag torque is generated when the drive plate 71 and the driven plate 72 are in contact with each other when the clutch is released. Therefore, when the clutch is released, it is necessary to avoid the contact between the drive plate 71 and the driven plate 72 as much as possible and reduce the drag torque. Hereinafter, based on FIG.8 and FIG.9, the drag torque reduction effect | action at the time of clutch release which reflects this is demonstrated.

  On the plate surface of the driven plate 72 of the dry multi-plate clutch 7 of the first embodiment, the direction of the centrifugal air flow generated in the outer diameter direction due to the plate rotation is changed to the axial direction at the position between the adjacent clutch plates. A radiation groove 791 is provided.

  Accordingly, when the clutch is disengaged, as described in the wear powder discharging action, when at least one of the clutch hub 3 and the clutch drum 6 rotates around the clutch rotation axis CL, the centrifugal fan having the clutch hub 3 as a blade is used. An effect is produced. Due to this centrifugal fan effect, air is sent from the clutch hub 3 side to the clutch drum 6 side in the outer diameter direction, the pressure on the clutch drum 6 side increases, and the pressure on the clutch hub 3 side decreases. Due to this pressure difference, a centrifugal airflow E is generated in which air moves in the outer diameter direction from the clutch hub 3 side to the clutch drum 6 side.

  As shown in FIG. 8, the centrifugal airflow E tends to flow between the adjacent drive plate 71 and the driven plate 72 in the outer diameter direction, but is directed in the axial direction at an intermediate position by the airflow diverting radiation groove 791. Is changed to an axial airflow H. That is, the centrifugal airflow E flowing from the inner peripheral end 791a opened of the airflow diverting radiation groove 791 is changed in direction by the outer peripheral end 791b closed by the inclined step surface to become an axial airflow H.

  With the airflow pressure of the axial airflow H whose direction is changed, the drive plate 71 and the driven plate 72 adjacent to each other are separated in the axial direction, and the plate is separated. That is, when the plate surfaces of the adjacent drive plate 71 and the driven plate 72 are in contact, all of the centrifugal airflow E flowing from the inner peripheral end 791a of the airflow diverting radiation groove 791 moves in the outer diameter direction. To do. Then, in order to change the direction of the centrifugal airflow E to the axial airflow H at the outer peripheral end 791b closed by the inclined step surface, the drive plate 71 and the driven plate 72 are separated by the strong airflow pressure of the axial airflow H. Next, when the adjacent drive plate 71 and driven plate 72 are separated with a clearance, a part of the centrifugal airflow E flowing from the inner peripheral end 791a of the airflow diverting radiation groove 791 is partially axial airflow H. The rest moves in the outer diameter direction. Therefore, the airflow pressure of the axial airflow H is weaker than the airflow pressure when the plate surface is in contact, but the drive plate 71 and the driven plate 72 are kept separated by the continuously applied airflow pressure. .

  In this way, by controlling the direction of the centrifugal airflow E, as shown in FIG. 9, a plate pulling state in which an air spring is interposed between adjacent drive plates 71 and driven plates 72 is realized. For this reason, the drag torque caused by the contact between the adjacent drive plate 71 and the driven plate 72 or partial contact is reduced.

  The centrifugal airflow E in which air moves in the outer diameter direction has a larger flow rate as the relative rotational difference between the drive plate 71 and the driven plate 72 increases. For this reason, the airflow pressure of the centrifugal airflow E whose direction is changed in the axial direction by the airflow diverting radiating groove 791 increases as the relative rotational difference increases. When the clutch has a higher relative rotational difference, more powerful plate separation is achieved. The action is secured.

As described above, the first embodiment employs a configuration in which the airflow diverting radiation groove 791 that changes the direction of the centrifugal airflow E to the axial airflow H is provided on the plate surface of the driven plate 72.
Therefore, the drag torque between the drive plate 71 and the driven plate 72 can be reduced when the clutch having a high relative rotational difference is released.

  In particular, in the case of the dry multi-plate clutch 7 applied to the hybrid driving force transmission device, if the drag torque is increased, the fuel consumption is deteriorated, and heat is generated by dragging at the contact portion between the plates 71 and 72. The life of the plate clutch 7 is reduced. On the other hand, drag torque can be effectively reduced when there is a high relative rotation difference. For this reason, energy loss at the time of a high relative rotation difference is suppressed, which leads to an improvement in fuel efficiency. Further, by avoiding contact between both plates 71 and 72 as much as possible, durability of the dry multi-plate clutch 7 is improved. It also leads to improved reliability.

Next, the effect will be described.
In the hybrid driving force transmission device of the first embodiment, the effects listed below can be obtained.

(1) In the driving force transmission device having the dry multi-plate clutch 7 for connecting and disconnecting the driving force,
The dry multi-plate clutch 7 is:
A first clutch plate (drive plate 71) that is spline-fitted to the clutch hub 3,
A second clutch plate (driven plate 72) that is spline-fitted to the clutch drum 6;
Centrifugal generated on the plate surface of at least one clutch plate (driven plate 72) of the first clutch plate (drive plate 71) and the second clutch plate (driven plate 72) and generated in the outer diameter direction by plate rotation An airflow diverting structure (airflow diverting radiation groove 791) that changes the direction of the airflow E in the axial direction at a position between adjacent clutch plates;
Is provided.
For this reason, it is possible to reduce drag torque between the clutch plates when the clutch having a high relative rotational difference is released.

(2) The airflow diverting structure is provided on the plate surface of the second clutch plate (driven plate 72), and opens the inner peripheral end 791a into which the centrifugal airflow E flows in the outer diameter direction. This is an airflow diverting radiation groove 791 having a radiation groove shape with a closed outer peripheral end 791b whose direction is changed to the axial direction (FIG. 8).
For this reason, in addition to the effect of (1) above, the direction of the centrifugal air flow E is changed to the axial air flow while the cost is increased by simply providing radial grooves on the plate surface of the second clutch plate (driven plate 72). An airflow diverting structure that changes to H can be obtained.

  The second embodiment is an example in which the airflow direction changing structure provided on the driven plate is different from the first embodiment.

First, the configuration will be described.
FIG. 10 is a diagram illustrating the configuration of the driven plate of the dry multi-plate clutch and the centrifugal airflow direction control action in the hybrid driving force transmission device according to the second embodiment. Hereinafter, the configuration of the driven plate 72 of the dry multi-plate clutch 7 will be described with reference to FIG.

As shown in FIG. 10, the inner peripheral end 792a into which the centrifugal airflow E flows in the outer diameter direction is opened on the plate surface of the driven plate 72 of Example 2, and the direction of the centrifugal airflow E is changed to the axial direction (axial airflow H ) Is provided with an airflow direction changing spiral groove 792 (airflow direction changing structure) in a spiral groove shape with the outer peripheral end 792b closed. Here, the spiral groove shape is a spiral curve that is changed so that the radius of curvature gradually decreases from the inflow side toward the close side.
Since other configurations are the same as those of the first embodiment, illustration and description thereof are omitted.

Next, the operation will be described.
In the second embodiment, the centrifugal airflow E when the driven plate 72 rotates is an airflow diverting spiral groove 792 corresponding to the change in the direction of the streamline accompanying the rotation, as shown by the arrow in FIG.
Therefore, compared to the airflow diverting radiation groove 791 of the first embodiment, the groove resistance received by the flow of the centrifugal airflow E is reduced, and smoothly flows from the inner peripheral end 792a toward the closed outer peripheral end 792b. As a result, the airflow pressure can be increased as compared with the first embodiment.
Since other operations are the same as those of the first embodiment, description thereof is omitted.

Next, the effect will be described.
In the hybrid driving force transmission device according to the second embodiment, the following effects can be obtained.

(3) The airflow diverting structure is provided on the plate surface of the second clutch plate (driven plate 72), and opens the inner peripheral end 792a into which the centrifugal airflow E flows in the outer diameter direction. This is an airflow diverting spiral groove 792 having a spiral groove shape with a closed outer peripheral end 792b whose direction is changed to the axial direction (FIG. 10).
For this reason, in addition to the effect (1), the groove resistance received by the centrifugal airflow E is small, and an airflow diverting structure that changes the direction of the smoothly flowing centrifugal airflow E to the axial airflow H can be obtained.

  The third embodiment is an example in which the airflow direction changing structure provided on the driven plate is different from the first and second embodiments.

First, the configuration will be described.
FIG. 11 is a diagram illustrating the configuration of the driven plate of the dry multi-plate clutch and the centrifugal airflow direction control action in the hybrid driving force transmission device according to the third embodiment. Hereinafter, the configuration of the driven plate 72 of the dry multi-plate clutch 7 will be described with reference to FIG.

As shown in FIG. 11, the inner peripheral end 793a into which the centrifugal airflow E flows in the outer diameter direction is opened on the plate surface of the driven plate 72 of Example 3, and the direction of the centrifugal airflow E is changed to the axial direction (axial airflow H The air flow redirecting rib 793 (air flow redirecting structure) is provided in the shape of a fence with the outer peripheral end 793b to be changed to (1). Here, the height of the airflow diverting rib 793 is made equal to the depth of the airflow diverting radiation groove 791 and the airflow diverting spiral groove 792 of the first and second embodiments.
Since other configurations are the same as those of the first embodiment, illustration and description thereof are omitted.

Next, the operation will be described.
In the third embodiment, the airflow diverting structure is the airflow diverting rib 793, which is different from the airflow diverting radiation groove 791. However, even if the airflow path shape that changes the direction of the centrifugal airflow E to the axial direction (axial airflow H) is the airflow diverting rib 793, the airflow diverting radiation groove 791 flows. However, since it becomes the same, the same operation as in the first embodiment is shown.
Since other operations are the same as those of the first embodiment, description thereof is omitted.

Next, the effect will be described.
In the hybrid driving force transmission device according to the third embodiment, the following effects can be obtained.

(4) The airflow diverting structure is provided on a plate surface of the second clutch plate (driven plate 72), and opens an inner peripheral end 793a into which the centrifugal airflow E flows in the outer diameter direction. This is an airflow redirecting rib 793 having an enclosure shape with a closed outer peripheral end 793b whose direction is changed to the axial direction (FIG. 11).
For this reason, in addition to the effect of (1) above, the airflow direction change that changes the direction of the centrifugal airflow E to the axial airflow H while suppressing the increase in cost to increase the rigidity of the second clutch plate (driven plate 72). A structure can be obtained.

  The fourth embodiment is an example in which the airflow direction changing structure provided on the driven plate is different from the first to third embodiments.

First, the configuration will be described.
FIG. 12 is a diagram illustrating the configuration of the driven plate of the dry multi-plate clutch and the centrifugal airflow direction control action / wear powder discharge action in the hybrid driving force transmission device of the fourth embodiment. Hereinafter, the configuration of the driven plate 72 of the dry multi-plate clutch 7 will be described with reference to FIG.

On the plate surface of the driven plate 72 of the fourth embodiment, as shown in FIG. 12, an inner peripheral end 794a into which the centrifugal airflow E flows in the outer diameter direction is opened, and a part of the direction of the centrifugal airflow E is directed in the axial direction. An airflow diverting step radiating groove 794 (airflow diverting structure) having a stepped radiating groove shape having a partially closed outer peripheral end 794b closed halfway so as to be changed is provided. Here, the depth to the partially closed outer peripheral end 794b of the airflow diverting step radiating groove 794 is equal to that of the airflow diverting radiating groove 791 of Example 1, and the groove is directed from the partially closed outer peripheral end 794b toward the outer diameter direction. This depth is suppressed to about half the depth of the airflow diverting radiation groove 791 of the first embodiment.
Since other configurations are the same as those of the first embodiment, illustration and description thereof are omitted.

Next, the operation will be described.
First, in Examples 1 to 3, the drive plate 71 shared the wear powder discharging function using the centrifugal airflow E, and the driven plate 72 shared the drag torque reduction function using the centrifugal airflow E. .

On the other hand, Example 4 is an example in which the driven plate 72 shares the two functions of the abrasion powder discharging function using the centrifugal airflow E and the drag torque reducing function.
That is, as shown in FIG. 12, the centrifugal air flow E is a partially closed outer peripheral end in which the centrifugal air flow E flowing in from the inner peripheral end 794a opened of the air flow diverting step radiation groove 794 is partially closed by the inclined step surface. When reaching 794b, a part of the flowing centrifugal airflow E becomes an axial airflow H in which the direction of the centrifugal airflow E is changed, and the rest exits in the outer diameter direction without changing the direction of the centrifugal airflow E. Therefore, the axial airflow H exhibits the drag torque reducing function as in the first embodiment, and the centrifugal airflow E that escapes in the outer diameter direction exhibits the wear powder discharging function of discharging the wear powder onto the airflow and discharging it to the outside.
Since other operations are the same as those of the first embodiment, description thereof is omitted.

Next, the effect will be described.
In the hybrid driving force transmission device according to the fourth embodiment, the following effects can be obtained.

(5) The airflow diverting structure (airflow diverting step radiating groove 794) is provided on the plate surface of the second clutch plate (driven plate 72), and the inner peripheral end where the centrifugal airflow E flows in the outer diameter direction. 794a is opened and has a partially closed outer peripheral end 794b that is closed halfway so as to change a part of the direction of the centrifugal airflow E in the axial direction (FIG. 12).
For this reason, in addition to the effect of (1) above, the wear powder discharging function and the drag torque using the centrifugal airflow E are provided while only the airflow turning structure is provided on the plate surface of the second clutch plate (driven plate 72). Two functions, a reduction function, can be achieved.
Moreover, the facing groove 76 provided in the drive plate 71 of the first to third embodiments can be omitted due to the effect of having two functions.

  As mentioned above, although the driving force transmission device of the present invention has been described based on the first to fourth embodiments, the specific configuration is not limited to these embodiments, and each claim of the claims Design changes and additions are permitted without departing from the spirit of the invention.

  In Examples 1-4, the example of the dry multi-plate clutch 7 by normal opening was shown. However, it may be an example of a dry multi-plate clutch that is normally closed using a diaphragm spring or the like.

  In the first to fourth embodiments, the drive plate 71 of the dry multi-plate clutch 7 is spline-fitted to the clutch hub 3, and the driven plate 72 of the dry multi-plate clutch 7 is spline-fitted to the clutch drum 6. However, the drive plate may be spline fitted to the clutch drum, and the driven plate may be spline fitted to the clutch hub.

  In Examples 1-4, the example which has the friction facing 73 in the drive plate 71 side of the dry type multi-plate clutch 7 was shown. However, it may be an example having a friction facing on the driven plate 72 side of the dry multi-plate clutch 7.

  In the first to fourth embodiments, there are facing grooves 76, ventilation holes 74, and ventilation openings 77, and the flow of airflow that actively draws a flow line of outside air → inner diameter side axial direction → radial direction → outer diameter side axial direction → outside air. An example in which the centrifugal airflow E is caused to flow by generating (F → E → G) has been shown. However, the present invention can also be applied to a dry multi-plate clutch that does not have a configuration that actively generates airflow. This is because the drive plate and the driven plate of the dry multi-plate clutch are spline-fitted through a gap that moves in the axial direction, thereby ensuring the flow of airflow in the axial direction. When the plate rotates, the flow in the inner diameter side axial direction is changed to the flow in the outer diameter direction (centrifugal airflow) due to the centrifugal pressure effect that increases the pressure on the outer diameter side, and a streamline that draws the flow in the outer diameter side axial direction is drawn. It depends on what you can do.

  In Examples 1-4, the example which provides an airflow direction change structure in the plate surface of the driven plate 72 of the dry multi-plate clutch 7 was shown. However, an example may be provided in which the airflow direction changing structure is provided on the plate surface of the drive plate of the dry multi-plate clutch, or an example in which an airflow direction changing structure is provided on both the plate surfaces of the drive plate and the driven plate.

  In the fourth embodiment, an example is shown in which the airflow turning step radiation groove 794 based on the first embodiment is provided as an airflow turning structure that achieves two functions of a wear powder discharging function and a drag torque reducing function. However, an example in which an airflow direction change step spiral groove based on the second embodiment may be provided, or an example in which an airflow direction change step rib based on the third embodiment may be provided.

  In the first to fourth embodiments, the application example to the hybrid driving force transmission device in which the engine Eng and the motor / generator 9 are mounted and the dry multi-plate clutch 7 is the travel mode transition clutch is shown. However, the present invention can also be applied to an engine driving force transmission device in which only an engine is mounted as a driving source for driving and a dry multi-plate clutch is a starting clutch, such as an engine vehicle. Further, the present invention can be applied to a motor driving force transmission device in which only a motor / generator is mounted as a travel drive source and a dry multi-plate clutch is a starting clutch, such as an electric vehicle and a fuel cell vehicle .

Eng Engine 9 Motor / Generator 3 Clutch hub 6 Clutch drum 7 Dry multi-plate clutch
71 Drive plate (first clutch plate)
72 Driven plate (second clutch plate)
73 Friction facing
791 Airflow diversion groove (airflow diversion mechanism)
791a Inner edge
791b Outer edge
792 Airflow turning spiral groove (airflow turning mechanism)
792a Inner edge
792b Outer edge
793 Airflow diverting rib (airflow diverting mechanism)
793a Inner edge
793b Outer edge
794 Airflow diversion step radiating groove (airflow diversion mechanism)
794a Inner peripheral edge
794b Partially closed outer peripheral edge E Centrifugal airflow F Inner diameter side axial airflow G Outer diameter side axial airflow H Axial direction airflow

Claims (5)

In a driving force transmission device having a dry multi-plate clutch that connects and disconnects transmission of driving force,
The dry multi-plate clutch is
A first clutch plate that is spline fitted to the clutch hub;
A second clutch plate splined to the clutch drum;
The direction of the centrifugal air flow that is provided on the plate surface of at least one of the first clutch plate and the second clutch plate and is generated in the outer diameter direction by rotating the plate is determined at the position between adjacent clutch plates. An airflow turning structure that changes direction,
A driving force transmission device comprising: The driving force transmission device according to claim 1,
The airflow diverting structure is provided on a plate surface of the second clutch plate, and an inner peripheral end where the centrifugal airflow flows in an outer diameter direction is opened, and an outer peripheral end which changes the direction of the centrifugal airflow in the axial direction is closed. A driving force transmission device characterized by being an airflow diverting radiating groove having a radiating groove shape. The driving force transmission device according to claim 1,
The airflow diverting structure is provided on a plate surface of the second clutch plate, and an inner peripheral end where the centrifugal airflow flows in an outer diameter direction is opened, and an outer peripheral end which changes the direction of the centrifugal airflow in the axial direction is closed. A driving force transmission device, characterized in that it is an airflow diverting spiral groove with a spiral groove shape. The driving force transmission device according to claim 1,
The airflow diverting structure is provided on a plate surface of the second clutch plate, and an inner peripheral end where the centrifugal airflow flows in an outer diameter direction is opened, and an outer peripheral end which changes the direction of the centrifugal airflow in the axial direction is closed. A driving force transmission device, characterized in that the rib is an airflow diverting rib with an enclosure shape. In the driving force transmission device according to any one of claims 2 to 4,
The airflow diverting structure is provided on a plate surface of the second clutch plate, opens an inner peripheral end where the centrifugal airflow flows in an outer diameter direction, and changes a part of the direction of the centrifugal airflow to the axial direction. And a partially closed outer peripheral end that is partially closed.