JP6094110B2 - Vehicle power transmission device - Google Patents

Description

  The present invention relates to a power transmission device for a vehicle equipped with a dry friction clutch, and more particularly to a dust discharge structure for discharging dust such as wear powder of the dry friction clutch.

  For example, there is a hybrid vehicle power transmission device that employs a dry friction clutch to switch connection / disconnection between an internal combustion engine and a motor. Such dry friction clutches have the advantage of less friction loss when the clutch is disengaged than wet friction clutches. However, dust such as wear powder generated from the friction material (facing lining) is transferred to some means. It is necessary to discharge.

  As such a dust discharge structure, Patent Document 1 discloses an outside air that allows a sealed space in which a dry friction clutch is accommodated and a damper side space to communicate with each other in a housing cover that partitions between the dry friction clutch and the damper on the engine side. A configuration in which a suction hole and an outside air discharge hole are formed is disclosed.

  In this case, a pressure difference is generated between the outside air suction hole located on the inner periphery side of the dry friction clutch and the outside air discharge hole located on the outer periphery side due to the centrifugal force caused by the rotation of the dry friction clutch itself, and from the outside air suction hole. Since the airflow flows to the outside air discharge hole, dust such as wear powder is discharged to the outside.

JP 2012-52570 A

  However, in the above configuration, since the outside air suction hole opens directly into the space in which the damper is accommodated, if the air in the space is disturbed as the damper rotates at high speed, the outside air is sucked from this space. There was still room for improvement, as air could not sufficiently flow into the holes.

  In this invention, a dry friction clutch comprising a hub side friction plate engaged with a clutch hub and a drum side friction plate engaged with a clutch drum is disposed in a sealed space partitioned by a cover member, It is premised on a vehicle power transmission device in which a rotating body that rotates coaxially with the dry friction clutch is disposed adjacent to the dry friction clutch via the cover member.

  Here, the cover member is formed with an intake hole for taking air into the sealed space and an exhaust hole for discharging air from the sealed space.

An outside air introduction passage isolated from the second space in which the rotating body is accommodated is formed along the cover member, and one end of the outside air introduction passage is sealed so as to take in the vehicle traveling wind. An opening is formed outside the space and the second space, and the other end is connected to the intake hole.
In one embodiment, the outside air introduction passage is configured by attaching a duct member to the cover member. In another aspect, the outside air introduction passage is formed as an internal passage in the cover member.

  A positive pressure due to vehicle traveling wind acts on one end of the outside air introduction passage, whereby outside air, that is, air is introduced into the intake hole of the cover member. This air flows through the dry friction clutch and is discharged through the exhaust hole together with dust such as wear powder. Since the outside air introduction passage is isolated from the second space in which the rotating body rotates at high speed, it is not affected by the air flow accompanying the rotation of the rotating body. It is definitely introduced.

  According to this invention, the outside air is guided to the air intake hole of the cover member without being affected by the airflow caused by the rotation of the rotating body adjacent to the dry friction clutch, and the dust around the dry friction clutch can be more reliably discharged. it can.

Sectional drawing of the principal part (part corresponding to the area | region (alpha) of FIG. 5) of the power transmission device which is one Example of this invention. Sectional drawing in the cross section along an exhaust hole. The cross-sectional view of a single clutch drum. Explanatory drawing which shows typically the intake duct member and exhaust duct member which were attached to the housing cover. The block diagram which shows simply the power transmission mechanism of the hybrid vehicle to which the said Example is applied. Sectional drawing of the principal part of the power transmission device which shows the 2nd Example of this invention. Explanatory drawing which shows typically the intake duct member and exhaust duct member in this 2nd Example. Sectional drawing which shows an example of the labyrinth structure provided in an external air intake part. Sectional drawing which shows the other example of the labyrinth structure provided in an external air intake part.

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

  FIG. 5 schematically shows a power train of a hybrid vehicle to which a power transmission device according to an embodiment of the present invention is applied. This vehicle is a front-wheel drive type 1-motor 2-clutch parallel hybrid vehicle, and includes an engine 1 and a motor generator 2 as vehicle drive sources. The engine 1 includes a known spark ignition gasoline engine, a compression self-ignition diesel engine, or the like. The motor generator 2 has both a function as an electric motor that rotates by receiving power supplied from a battery (not shown) and a function as a generator that regenerates rotational power and charges the battery.

  A damper 3 is provided between the engine 1 and the motor generator 2 to absorb vibrations in the rotational direction of the engine 1, and a first clutch 4 that switches between connection and disconnection of power transmission between the engine 1 and the motor generator 2 is provided. Is provided. The motor generator 2 is connected to a pair of drive wheels 7 via, for example, an automatic transmission 5 formed of a belt-type continuously variable transmission and a differential gear 6, and between the motor generator 2 and the automatic transmission 5, A two-clutch 8 is interposed. The second clutch 8 may be interposed between the automatic transmission 5 and the differential gear 6, and when the automatic transmission 5 is a stepped type, The clutch may also be used as the second clutch 8.

  The first clutch 4 is interposed between a clutch input shaft 4 </ b> A connected to the damper 3 and a clutch output shaft 4 </ b> B connected to the motor generator 2, and switches between disconnection and connection therebetween. For example, in the “electric vehicle running mode” in which only the motor generator 2 is the driving source, the first clutch 4 is released and the engine 1 is disconnected. Further, in the “hybrid vehicle travel mode” in which the engine 1 and the motor generator 2 are used together as a drive source, the engine 1 and the motor generator 2 are connected by fastening the first clutch 4. The second clutch 8 is engaged or semi-engaged during traveling, and is in an open state when the shift range is an N (neutral) range or a P (parking) range.

  FIG. 1 is a cross-sectional view showing details of a portion corresponding to a region α in FIG. The damper 3 is attached to an end portion of a crankshaft (not shown) of the engine 1, has a substantially disc shape arranged coaxially with the clutch input shaft 4 </ b> A, and has a plurality of vibration absorbing components. A damper spring 3A is provided along the circumferential direction, and the rotational power of the engine 1 is transmitted to the clutch side plate 3B via the damper spring 3A. The clutch side plate 3B is coupled to the clutch input shaft 4A, and rotates around the shaft integrally with the clutch input shaft 4A. The damper 3 is accommodated in a space 10A at the end of the engine block 10 that opens in a bell mouth shape.

  The motor generator 2 and the first clutch 4 are accommodated in the clutch housing 11 made of a metal casting part adjacent to the damper 3 in the axial direction with a predetermined gap. The clutch housing 11 is roughly constituted by a housing main body 12 and a housing cover 13 which is attached to an opening of the housing main body 12 on the damper 3 side and closes the opening, and is supported outside the vehicle compartment. It is fixed to the end of the engine block 10. In the clutch housing 11, the clutch input shaft 4 </ b> A and the clutch output shaft 4 </ b> B are rotatably penetrated and supported via bearings 15 and 16.

  The motor generator 2 is a synchronous AC motor, and includes a rotor 18 in which a permanent magnet 17 is embedded, a stator 20 disposed so as to face the rotor 18 via an air gap 19, and the stator 20. Stator coil 21. The stator 20 is fixed to the housing body 12 described above. The rotor 18 is connected to the clutch output shaft 4B via a clutch drum 23 and a ring member 24, which will be described later, and rotates around the shaft integrally with the clutch output shaft 4B. The first clutch 4 is accommodated in the inner peripheral side of the motor generator 2, specifically, in the radial gap between the rotor 18 of the motor generator 2 and the clutch input shaft 4 </ b> A.

  The first clutch 4 is a normally open dry multi-plate friction clutch that forms a main part of the present embodiment, and is hereinafter referred to as “dry clutch 4”. The dry clutch 4 is fixed to the outer periphery of the clutch input shaft 4A and rotates integrally with the clutch input shaft 4A. The dry clutch 4 is provided on the outer periphery of the clutch hub 22 so as to be coaxial and relatively rotatable. And a clutch drum 23. The clutch drum 23 is fixed to the clutch output shaft 4B via the ring member 24, and rotates integrally with the clutch output shaft 4B. The rotor 18 of the motor generator 2 described above is fixed to the outer peripheral side of the clutch drum 23.

  A plurality of ring-shaped hub-side friction plates 25 extending radially outward are attached to the outer peripheral side of the clutch hub 22 so as to be movable in the axial direction. Specifically, a plurality of spline grooves 22A extending in the axial direction are formed on the outer periphery of the clutch hub 22, and a plurality of spline teeth formed on the inner periphery of each hub side friction plate 25 are splined in the spline grooves 22A. By engaging, each hub-side friction plate 25 is supported in a state where it can move in the axial direction with respect to the clutch hub 22 and the movement in the circumferential direction is restricted.

  A plurality of ring-shaped drum-side friction plates 26 extending radially inward are attached to the inner peripheral side of the clutch drum 23 so as to be movable in the axial direction. Specifically, a spline groove 23A extending in the axial direction is formed on the inner periphery of the clutch drum 23, and spline teeth formed on the outer periphery of the drum side friction plate 26 are spline engaged with the spline groove 23A. Each drum-side friction plate 26 is supported in a state where it can move in the axial direction with respect to the clutch drum 23 and the movement in the circumferential direction is restricted.

  The hub-side friction plates 25 and the drum-side friction plates 26 are alternately arranged in the axial direction, and ring-shaped friction materials 27 serving as facing linings are interposed between the facing surfaces. The friction material 27 is adhered to, for example, one of the hub side friction plate 25 and the drum side friction plate 26. The hub-side friction plate 25 and the drum-side friction plate 26 are driven in the axial direction by a hydraulic actuator to be released or fastened to each other, thereby interrupting and connecting the power transmission between the clutch input shaft 4A and the clutch output shaft 4B. Can be switched.

  The hydraulic actuator includes a hydraulic piston 28 that is operated by hydraulic pressure supplied from a hydraulic circuit (not shown) to the hydraulic chamber 31, and a piston arm 28 a that moves forward and backward in the axial direction of the dry clutch 4 in conjunction with the hydraulic piston 28. And a return spring 29. By supplying hydraulic pressure to the hydraulic chamber 31, the piston arm 28 a operates together with the hydraulic piston 28 against the spring force of the return spring 29 in the right direction in FIG. 1, and is connected to the hub side friction plate 25 via the friction material 27. The drum side friction plate 26 is brought into pressure contact with each other, and the clutch is engaged. On the other hand, when the hydraulic pressure is released, the piston arm 28a moves to the left in FIG. 1 together with the hydraulic piston 28 by the spring force of the return spring 29, the hub side friction plate 25 and the drum side friction plate 26 are separated, and the clutch It becomes an open state.

  In addition to the hydraulic chamber 31 described above, a clutch chamber 30 in which the dry clutch 4 is accommodated and a motor chamber 32 in which the motor generator 2 is accommodated are formed in the clutch housing 11. A plurality of seal members 33 to 37 are provided so that hydraulic oil, dust and the like do not enter and move between. In particular, the clutch chamber 30 is partitioned from the hydraulic actuator by two oil seals 33 and 34 and is a sealed space partitioned from the motor chamber 32 by a seal member 35.

  Here, in the present embodiment, the clutch drum 23 includes an inner cylindrical portion 51 with which the drum-side friction plate 26 engages, and a predetermined outside of the inner cylindrical portion 51 in the radial direction, as shown in FIG. A so-called double drum structure having an outer cylindrical portion 52 fixed with a gap 50 and rotating integrally with the inner cylindrical portion 51 is formed. A plurality of spline grooves 23 </ b> A extending in the axial direction are formed on the inner peripheral surface side of the inner cylindrical portion 51 by stepping the concave and convex portions by pressing the relatively thin cylindrical member. Each spline groove 23A has a wide structure in which two adjacent spline teeth 26A formed on the outer periphery of the drum-side friction plate 26 are fitted, and a space 26B between the two spline teeth 26A is in the axial direction. It also functions as a passage through which air flows. The outer cylindrical portion 52 is a cast part having a substantially cylindrical shape that is thicker than the inner cylindrical portion 51, and is fixed to the inner cylindrical portion 51 by welding or the like. A rotor mounting surface 53 which is a cylindrical surface to which the rotor 18 is fixed is formed by machining such as grinding.

  Thus, the clutch drum 23 has a double drum structure, so that the motor mounting surface 53 with high surface accuracy is formed on the outer peripheral surface of the outer cylindrical portion 52, which is a cast part, by machining, while the spline The groove 23A can be easily formed by press working, and is easy to manufacture and excellent in productivity.

  As shown in FIG. 1, the inner cylindrical portion 51 is formed with a plurality of through holes 54 penetrating in the radial direction as part of the air flow path. Each through-hole 54 is in an axial position that generally corresponds between two adjacent drum-side friction plates 26, and the central passage portion, the inner cylindrical portion 51, and the outer cylindrical portion 52 of each spline groove 23 </ b> A described above. And the gap 50 between them.

  Next, a basic dust discharge structure of the dry clutch 4 will be described with reference to FIG. A substantially disc-shaped housing cover 13 constituting one wall portion of the clutch housing 11 is interposed in the axial gap 40 between the damper 3 rotating around the shaft and the dry clutch 4, and accommodates the dry clutch 4. The clutch chamber 30 corresponding to the “sealed space” and the space 10A corresponding to the “second space” where the damper 3 is located are partitioned from each other. The housing cover 13 is formed with an intake hole 41 for taking air into the clutch chamber 30 and an exhaust hole 42 for discharging air from the clutch chamber 30. The intake hole 41 is opened in the vicinity of the engaging portion between the spline groove 22A of the clutch hub 22 and the spline teeth of the hub side friction plate 25, that is, in the radial position slightly closer to the inner peripheral side than the friction material 27 or in the vicinity thereof. doing. As shown in FIG. 2, the exhaust hole 42 is located on the outer peripheral side relative to the intake hole 41, and is located at or near the radial position corresponding to the gap 50 of the clutch drum 23 having a double drum structure. It is open.

  Due to the centrifugal force accompanying the rotation of the dry clutch 4, a pressure difference is produced in the radial direction in the clutch chamber 30. That is, the pressure on the outer peripheral side in which the exhaust hole 42 is formed is relatively higher than the pressure on the inner peripheral side in which the intake hole 41 is formed. Basically, this pressure difference in FIG. As shown by arrows K1 to K3, air is introduced into the clutch chamber 30 through the intake hole 41 (K1), flows in the dry clutch 4 radially outward (K2), and then from the exhaust hole 42. It is discharged to the outside of the clutch chamber 30 (K3). Specifically, the air supplied into the clutch chamber 30 through the intake hole 41 flows along the axial direction through the clearance of the spline engaging portion between the clutch hub 22 and the hub side friction plate 25 to the left side in FIG. After that, the gap between the hub side friction plate 25 and the drum side friction plate 26 in which the friction material 27 is interposed flows along the radial direction to the outer peripheral side as indicated by the arrow K2, and through the plurality of through holes 54. It flows into the gap 50 of the clutch drum 23 having a double drum structure, flows through the gap 50 to the right side in FIG. 1, and then is discharged to the outside through the exhaust hole 42. As described above, when air flows through the dry clutch 4, dust such as wear powder in the dry clutch 4 flows along with the air and is discharged from the exhaust hole 42 to the outside of the clutch chamber 30 together with the air flow.

  A groove extending in the radial direction may be provided in the friction material 27 and the friction plates 25 and 26 so as to promote the flow of air and dust in the dry clutch 4, and the spline engagement of the friction plates 25 and 26 is also possible. You may make it provide the hole penetrated to an axial direction in the vicinity of a part.

  In the basic dust discharge structure as described above, if the intake hole 41 opens directly into the space 10A in which the damper 3 is accommodated, the damper 3 rotates at high speed and the air in the space 10A is agitated. Therefore, the inflow of air from the space 10A to the intake hole 41 tends to be unstable.

  Therefore, in this embodiment, a tubular intake duct member 43 is attached to the side surface of the housing cover 13 on the damper 3 side in order to obtain the air flows K1 to K3 in the clutch chamber 30 more reliably. Thus, an outside air introduction passage 45 that is isolated from the space 10 </ b> A is formed along the housing cover 13. As shown in FIGS. 1 and 4, the intake duct member 43 is positioned above the hole 13A in the center of the shaft of the housing cover 13 through which the clutch input shaft 4A passes and is substantially vertically oriented in the on-vehicle state. It extends linearly. The intake duct member 43 is made of, for example, a synthetic resin molded product, and is fixed to the housing cover 13 using a fixing tool such as a bolt or an adhesive.

  One end of the intake duct member 43, that is, one end of the outside air introduction passage 45 communicates with the intake hole 41 of the housing cover 13. The other end extends to the outside of the engine block 10 and is opened as an outside air inlet 46 in a predetermined direction so that vehicle traveling wind can be taken in. For example, since the power train of the embodiment is mounted on the vehicle body in a so-called horizontal type, the outside air is directed toward the circumferential direction of the dry clutch 4 as shown in FIG. An intake 46 is provided. It should be noted that the outside air intake 46 can be provided in any other suitable position and direction as long as the position and direction are positive when the vehicle is traveling.

  Further, as shown in FIGS. 2 and 4, a small exhaust duct member 44 having one end opened is attached to the exhaust hole 42 of the housing cover 13, and the exhaust discharge direction in the space 10 </ b> A is The damper 3 is arranged along the rotation direction (clockwise direction in FIG. 4). The exhaust duct member 44 is made of a synthetic resin molded product or the like, and is fixed to the housing cover 13 using a fixture such as a bolt or an adhesive. The exhaust duct member 44 is not essential in the present invention, and the exhaust hole 42 may be configured to open directly toward the space 10A.

  As shown in FIG. 4, in the present embodiment, the intake hole 41 and the exhaust hole 42 each have an elliptical shape extending in the tangential direction of the dry clutch 4, and the intake duct member 43 and the exhaust duct member 44. Are arranged at positions slightly offset in the circumferential direction of the dry clutch 4 so that they do not interfere with each other.

  In the configuration of the embodiment as described above, the vehicle traveling wind acts on the outside air intake 46 while the vehicle is running, and this portion becomes a positive pressure, so that the space between the outside air intake 46 and the exhaust hole 42 is increased. As a result, a large pressure difference is obtained. As a result, as shown by an arrow K4 in FIG. 1, the outside air, that is, the air surely flows into the outside air introduction passage 45, and the air flow along the arrows K1, K2, and K3 is strengthened. The In particular, since the outside air introduction passage 45 is isolated from the space 10A in which the damper 3 is accommodated, air is stably introduced into the clutch chamber 30 without being affected by air turbulence due to the rotation of the damper 3, and more reliably. A good dust discharge effect.

  In addition, since relatively low temperature outside air is introduced into the clutch chamber 30, it is advantageous for cooling the dry clutch 4.

  Further, in the above embodiment, the intake hole 41 and the exhaust hole 42 are positioned above the rotation center of the dry clutch 4 and the outside air introduction passage 45 extends upward from the intake hole 41 in the vehicle-mounted state. Even when the vehicle enters a flooded road surface, it does not flood into the clutch chamber 30 until the water level becomes high.

  Further, in the above embodiment, since the outside air introduction passage 45 is configured by using the intake duct member 43 which is a separate part from the housing cover 13 of the clutch housing 11, the shape of the housing cover 13 cast from a metal material. The outside air introduction passage 45 along the housing cover 13 can be provided without changing the above. In addition, since the intake duct member 43 is not required to have particularly high strength and rigidity, it can be easily formed even if it has a complicated tube shape by forming a mold with, for example, a synthetic resin material. In addition, weight reduction and cost reduction can be achieved.

  An external air introduction passage may be formed in the housing cover 13 itself as an internal passage. In this case, although the shape of the housing cover 13 is complicated, the number of parts and the number of assembly steps are reduced.

  Next, FIGS. 6 and 7 show a second embodiment in which the outside air introduction passage 45 is extended downward from the intake hole 41 in the vertical direction. The outside air introduction passage 45 is configured by attaching an intake duct member 43 made of a synthetic resin molded product or the like to the housing cover 13 as in the above-described embodiment, and one end communicates with the intake hole 41 of the housing cover 13. Yes. Further, the other end extends to the outside of the engine block 10 and is also opened as a position and direction where the vehicle running wind can be taken in as the outside air intake 46.

  Also in this embodiment, in order to reduce the risk of water intrusion into the clutch chamber 30, the intake hole 41 and the exhaust hole 42 are located above the rotational center of the dry clutch 4, and therefore the intake duct member 43. As shown in FIG. 7, it extends downward through the side of the center of rotation.

  The outside air introduction passage 45 may be formed in the housing cover 13 itself without using the separate intake duct member 43.

  As illustrated in this embodiment, in the present invention, the outside air introduction passage 45 can be extended to an arbitrary position suitable for taking in vehicle traveling wind.

  Next, FIG. 8 and FIG. 9 each show an embodiment in which a labyrinth structure for suppressing intrusion of rainwater is provided at the end of the outside air introduction passage 45 opened outside the engine block 10.

  In the embodiment of FIG. 8, three partition walls 61 are provided between the outside air inlet 46 and the upper end of the outside air introduction passage 45, and the air flow is approximately 90 ° downward from the outside air inlet 46. After being bent, it makes a 180 ° U-turn and then makes another 180 ° U-turn, and then flows downward through the outside air introduction passage 45. Therefore, rainwater contained in the outside air is separated, and entry into the clutch chamber 30 is suppressed. In addition, you may make it provide a drain hole in the bottom face of the center U-turn part.

  The embodiment of FIG. 9 is basically the same, but in this embodiment, the flow path itself of the outside air introduction passage 45 is folded back as shown in the example of FIG. 8 by three partition walls 61A having a thickness. ing.

  8 and 9, the outside air inlet 46 is configured to open obliquely downward, thereby suppressing the inflow of rainwater from above.

  As mentioned above, although one Example of this invention was described in detail, this invention is not limited to these Examples, A various change is possible. For example, in the above embodiment, the present invention is applied to the power transmission device of a front wheel drive type hybrid vehicle, but various vehicles provided with a dry friction clutch in the power transmission path, such as a rear wheel drive type hybrid vehicle, The present invention can also be applied to an electric vehicle that does not include an engine or a vehicle that uses only an engine as a drive source. Further, the dry friction clutch is not limited to the multi-plate type as in the above embodiment, but may be a single-plate type.

3 ... Damper 4 ... First clutch (dry clutch)
4A ... Clutch input shaft 4B ... Clutch output shaft 11 ... Clutch housing 13 ... Housing cover 22 ... Clutch hub 23 ... Clutch drum 25 ... Hub side friction plate 26 ... Drum side friction plate 27 ... Friction material 28 ... Hydraulic piston 30 ... Clutch chamber DESCRIPTION OF SYMBOLS 41 ... Intake hole 42 ... Exhaust hole 43 ... Intake duct member 44 ... Exhaust duct member 45 ... Outside air introduction passage 46 ... Outside air intake

Claims (4)

A dry friction clutch comprising a hub side friction plate engaged with a clutch hub and a drum side friction plate engaged with a clutch drum is disposed in a sealed space partitioned by a cover member, and the dry friction clutch In a vehicle power transmission device in which a rotating body that rotates coaxially with the dry friction clutch is disposed through the cover member,
The cover member is formed with an intake hole for taking air into the sealed space and an exhaust hole for discharging air from the sealed space.
An outside air introduction passage that is isolated from the second space in which the rotating body is accommodated is formed along the cover member, and one end of the outside air introduction passage includes the sealed space and the sealed space so as to take in the vehicle traveling wind. Opening outside the second space, and the other end is connected to the intake hole ,
The power transmission device for a vehicle, wherein the outside air introduction passage is configured by attaching a duct member to the cover member . A dry friction clutch comprising a hub side friction plate engaged with a clutch hub and a drum side friction plate engaged with a clutch drum is disposed in a sealed space partitioned by a cover member, and the dry friction clutch In a vehicle power transmission device in which a rotating body that rotates coaxially with the dry friction clutch is disposed through the cover member,
  The cover member is formed with an intake hole for taking air into the sealed space and an exhaust hole for discharging air from the sealed space.
  An outside air introduction passage that is isolated from the second space in which the rotating body is accommodated is formed along the cover member, and one end of the outside air introduction passage includes the sealed space and the sealed space so as to take in the vehicle traveling wind. Opening outside the second space, and the other end is connected to the intake hole,
  The power transmission device for a vehicle, wherein the outside air introduction passage is formed as an internal passage in the cover member. The power transmission device for a vehicle according to claim 1 or 2 , wherein the intake hole is formed to open toward an engagement portion between the clutch hub and the hub-side friction plate.   The vehicle power transmission device according to any one of claims 1 to 3, wherein an outside air intake portion at one end of the outside air introduction passage has a labyrinth structure.

Images