JP2018128052A - Frictional engagement device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce an axial size of a frictional engagement device.SOLUTION: A frictional engagement device comprises: an inside member 22; an outside member 21b for covering an external periphery of the inside member coaxially with the inside member; a plurality of first engagement carriers 23 which are radially aligned in a direction around an axis in a region being an internal periphery of the outside member and being an external periphery of the inside member, and which include wedge parts attached to either of the inside member or the outside member so as to be displaceable in a direction orthogonal to an axial direction, gradually thinned in axial thicknesses toward the other of the inside member and the outside member, and have wedge parts which are protruded in substantially-V shapes; second engagement carriers 24 which are arranged at the other of the inside member and the outside member, gradually thinned in thicknesses in the axial direction toward protrusion directions of the wedge parts, and have recesses which are recessed in substantially-V shapes; and engagement drive parts 22a, 25 for causing the wedge parts to be friction-engaged with the second engagement carriers in the recesses by pressurizing the first engagement carriers to a direction orthogonal to the axial direction.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a friction engagement device in a vehicle such as a multi-plate clutch.

Some vehicles include a friction engagement device such as a forward clutch in a forward / reverse switching mechanism.
As a friction engagement device, for example, as known as a multi-plate clutch, a plurality of internal friction plates that are spline-engaged with an inner member as a clutch hub or the like and are axially displaceable, Some of them have a plurality of outer friction plates that are alternately arranged with the friction plates and are spline-engaged with an outer member such as a clutch drum so as to be displaceable in the axial direction. In this type of friction engagement device, a configuration is adopted in which the piston is hydraulically driven in the axial direction to frictionally engage the inner friction plate and the outer friction plate. The piston is urged by the return spring in the direction opposite to the hydraulic drive direction, and the piston is displaced in the reverse direction by lowering the drive hydraulic pressure to release the engaged state.

  In addition, about the related prior art, the following patent documents can be mentioned.

Japanese Utility Model Publication No. 62-81731 Japanese Patent Laid-Open No. 1-6520

  In the friction engagement device as described above, since the piston is driven in the axial direction when the friction plate is frictionally engaged, a space for reciprocating the piston in the axial direction is required. This leads to an increase in size in the axial direction.

  The present invention has been made in view of the above-described problems, and an object thereof is to reduce the size of the friction engagement device in the axial direction.

  A friction engagement device according to the present invention is a friction engagement device in a vehicle, and is an inner member, an outer member that covers an outer periphery of the inner member coaxially with the inner member, and an outer periphery of the inner member. The outer member is radially arranged in the direction around the axis in a region that is the inner periphery of the outer member, and is attached to either the inner member or the outer member so as to be displaceable in the direction perpendicular to the axis. A plurality of first engagement carriers having wedge portions that are gradually reduced in thickness in the axial direction toward any one of the members and project in a substantially V shape, and either one of the inner member or the outer member And a second engagement carrier having a recess that is gradually reduced in the axial direction toward the protruding direction of the wedge portion and is recessed in a substantially V shape, and the first engagement carriers are orthogonal to each other. The wedge portion is pushed in the direction Engaging driving section for frictionally engaged with the second engagement carrier in parts, but with a.

  According to the above configuration, the piston that is displaced in the axial direction is not necessary when the first engagement carrier and the second engagement carrier are frictionally engaged.

  In the above-described friction engagement device according to the present invention, the engagement driving unit can be configured to press the first engagement carrier based on hydraulic pressure.

  As a result, it is not necessary to add an electromagnetic actuator such as a motor or a solenoid as driving means for the first engagement carrier.

  In the above-described friction engagement device according to the present invention, the first engagement carrier is attached to the inner member, and the engagement driving portion has an engagement oil passage formed in the inner member. And it can be set as the structure which presses said 1st engagement carrier to an outer peripheral direction based on the oil_pressure | hydraulic of the said oil path for engagement.

  Since the inner member is smaller in diameter than the outer member, the first engagement carrier is attached to the inner member as described above, and the engagement oil passage is provided in the inner member. It becomes easy to reduce the volume.

  In the friction engagement device according to the present invention, the biasing member that biases the first engagement carrier in the inner circumferential direction is provided, and the inner member is a rotatable member, and the biasing member Has an urging force that counteracts the centrifugal force acting on the first engagement carrier by rotating integrally with the inner member and the pressing force applied to the first engagement carrier due to the centrifugal hydraulic pressure. It can be configured.

  As a result, the first engagement carrier and the second engagement carrier are not engaged unless the hydraulic pressure is supplied to the engagement oil passage at a predetermined pressure.

  In the above-described friction engagement device according to the present invention, a plurality of wedge rows in which the first engagement carriers are arranged in the radial direction are arranged in the axial direction, and the first wedge carriers are arranged between the adjacent wedge rows. The centers of the engagement carriers in the direction around the axis can be separated from each other in the direction around the axis.

  Thereby, when each first engagement carrier has a pedestal portion protruding in the axial direction from the wedge portion, the arrangement interval in the axial direction of the wedge row is reduced while preventing the pedestal portions from being buffered. Is possible.

  In the friction engagement device according to the present invention described above, in the first engagement carrier, the tip of the wedge portion is formed from an intersection line formed by intersecting the pair of inclined surfaces having the substantially V shape. Also, it is possible to adopt a configuration that is positioned on either one of the inner member and the outer member.

  Thereby, it is possible to reduce the depth of the recess in the second engagement carrier.

  According to the present invention, the size of the friction engagement device in the axial direction can be reduced.

It is the figure which showed the structure outline | summary of the vehicle provided with the friction engagement apparatus as embodiment which concerns on this invention. It is the longitudinal cross-sectional view which showed typically the structure of the friction engagement apparatus as a prior art example. It is the longitudinal cross-sectional view which showed typically the structure of the friction engagement apparatus as embodiment. It is a figure for demonstrating the inclination-angle of the slope in a wedge part. It is explanatory drawing about the example of arrangement | positioning of a 1st engagement carrier. It is explanatory drawing about the other example of arrangement | positioning of a 1st engagement carrier. It is the external view which looked at the 1st engagement carrier in an embodiment from the side facing the tip of a wedge part. It is the external view which looked at the 1st engagement carrier in an embodiment from the front side. It is a side view of the 1st engagement carrier in an embodiment. It is sectional drawing which cut | disconnected the 1st engagement carrier in embodiment by the A-A 'line | wire shown in FIG. It is the external view which looked at the attaching part with which the friction engagement apparatus as embodiment is provided from the front side. FIG. 9 is a diagram illustrating an exploded cross section of the first engagement carrier and a cross section of the attachment portion taken along line A-A ′ illustrated in FIG. 8. It is the figure which represented the state by which the 1st engagement carrier in the embodiment was hydraulically driven as sectional drawing by the A-A 'line of FIG. It is a figure for demonstrating the front-end | tip shape of a wedge part.

<1. Overview of vehicle configuration>
FIG. 1 is a diagram showing a configuration outline of a vehicle 1 as an embodiment according to the present invention. In FIG. 1, only the configuration of the main part according to the present invention is extracted from the configuration of the vehicle 1.
The vehicle 1 of the present embodiment is configured as a four-wheeled vehicle by two-wheel drive, and includes an engine 2 as a traveling power source, a power converter mechanism 3 including a torque converter 4, a forward / reverse switching mechanism 5, and a continuously variable transmission 6. , A hydraulic control unit 7 that controls hydraulic pressure of hydraulic oil in the power transmission mechanism 3, a gear 8 and a gear 9, a differential gear 10, a drive wheel 11a and a drive wheel 11b, an engine control unit 12, and a transmission mechanism control unit. 13 and a bus 14.

  The engine 2 is a traveling power source (prime mover) that causes the vehicle 1 to travel, and generates power that consumes fuel and acts on the drive wheels 11 a and 11 b of the vehicle 1. The engine 2 burns fuel to generate mechanical power (engine torque) on a crankshaft 2a that is an engine output shaft, and the mechanical power can be output from the crankshaft 2a toward the drive wheels 11a and 11b. Has been.

The power transmission mechanism 3 is provided in a power transmission path from the engine 2 to the drive wheels 11a and 11b, and transmits power from the engine 2 to the drive wheels 11a and 11b. However, it can be operated as lubricating oil or cooling oil).
In the power transmission mechanism 3, the crankshaft 2 a of the engine 2 and the primary shaft Ps of the continuously variable transmission 6 are connected via the torque converter 4, the forward / reverse switching mechanism 5, and the like, and the secondary shaft Ss of the continuously variable transmission mechanism 6. Are connected to the drive wheels 11a and 11b via the gear 8, the gear 9, the differential gear 10 and the like.

  The torque converter 4 is disposed between the engine 2 and the forward / reverse switching mechanism 5 and is configured to amplify (or maintain) the power torque transmitted from the engine 2 and transmit the torque to the forward / reverse switching mechanism 5. Has been. The torque converter 4 includes a pump impeller 4a and a turbine runner 4b that are rotatably arranged opposite to each other, and the pump impeller 4a is coupled to the crankshaft 2a via the front cover 4c so as to be rotatable together with the turbine runner 4b. It is configured to be connected to the mechanism 5. Along with the rotation of the pump impeller 4a and the turbine runner 4b, a viscous fluid such as hydraulic fluid interposed between the pump impeller 4a and the turbine runner 4b circulates to allow a differential between the input and output. However, the torque can be amplified and transmitted.

  The torque converter 4 further includes a lock-up clutch 4d provided between the turbine runner 4b and the front cover 4c and connected to the turbine runner 4b so as to be integrally rotatable. The lock-up clutch 4d is operated by the pressure of hydraulic oil supplied from the hydraulic control unit 7, and is switched between an engaged state (lock-up ON) and an open state (lock-up OFF) with the front cover 4c. In a state where the lock-up clutch 4d is engaged with the front cover 4c, the front cover 4c (that is, the pump impeller 4a) and the turbine runner 4b are engaged, and the relative rotation between the pump impeller 4a and the turbine runner 4b is restricted, Since the differential between the input and the output is prohibited, the torque converter 4 transmits the torque transmitted from the engine 2 to the forward / reverse switching mechanism 5 as it is.

The forward / reverse switching mechanism 5 is configured to be able to change the power (rotational output) from the engine 2 and to switch the rotational direction of the power (finally the rotational direction of the drive wheels 11a and 11b). . The forward / reverse switching mechanism 5 includes a planetary gear mechanism 5a, a forward clutch (forward clutch) CL, a reverse brake (reverse brake) BR, and the like. The planetary gear mechanism 5a is a differential mechanism that includes a sun gear, a ring gear, a carrier, and the like as a plurality of rotational elements that can be differentially rotated with each other, and the forward clutch CL and the reverse brake BR are included in the planetary gear mechanism 5a. The friction engagement device is used for switching the operation state. In this example, the forward clutch CL is configured by a frictional engagement device (friction engagement device) as a multi-plate clutch, and specifically, a hydraulic wet multi-plate clutch.
The configuration of the forward clutch CL will be described later.

In the forward / reverse switching mechanism 5, the forward clutch CL and the reverse brake BR are operated by the pressure of the hydraulic oil supplied from the hydraulic control unit 7, and the operating state is switched. Specifically, the forward / reverse switching mechanism 5 is configured to rotate the power from the engine 2 in the forward rotation (the vehicle 1 is turned on) when the forward clutch CL is in an engaged state (ON state) and the reverse brake BR is in a released state (OFF state). (The direction in which the primary shaft Ps rotates when moving forward) is transmitted to the primary shaft Ps. On the other hand, the forward / reverse switching mechanism 5 reversely rotates the power from the engine 2 when the forward clutch CL is disengaged and the reverse brake BR is engaged (the direction in which the primary shaft Ps rotates when the vehicle 1 moves backward). ) To the primary shaft Ps. In the forward / reverse switching mechanism 5, both the forward clutch CL and the reverse brake BR are in a released state at the neutral time.
Hereinafter, the control system for controlling the engagement / release of the forward clutch CL and the reverse brake BR as described above will be collectively referred to as “CB control system 5b”.

  The continuously variable transmission 6 is provided between the forward / reverse switching mechanism 5 and the drive wheels 11a and 11b in the power transmission path from the engine 2 to the drive wheels 11a and 11b, and continuously powers the engine 2 (continuously). This is a transmission device that can output at a variable speed. Specifically, the continuously variable transmission 6 changes the rotational power (rotational output) from the engine 2 transmitted (input) to the primary shaft Ps at a predetermined gear ratio to the secondary shaft Ss that is the transmission output shaft. The power transmitted from the secondary shaft Ss toward the drive wheels 11a and 11b is output.

  The continuously variable transmission 6 is spanned between a primary pulley 61 provided for the primary shaft Ps, a secondary pulley 64 provided for the secondary shaft Ss, and between the primary pulley 61 and the secondary pulley 64 (winding). It is configured as a continuously variable transmission (Continuously Variable Transmission = CVT) including a winding member 67 such as a belt or a chain.

  The primary pulley 61 is coaxially opposed to a primary-side fixed sheave 62 that is fixed in position relative to the primary shaft Ps and rotates integrally with the primary shaft Ps, and a primary-side movable sheave 63 that can be displaced in the axial direction of the primary shaft Ps. It is formed by arranging. The secondary pulley 64 is coaxial with a secondary-side fixed sheave 65 that is fixed in position relative to the secondary shaft Ss and rotates integrally with the secondary shaft Ss, and a secondary-side movable sheave 66 that can be displaced in the axial direction of the secondary shaft Ss. Are formed so as to face each other. The winding member 67 is a substantially V-shaped groove (hereinafter referred to as “V-groove”) formed between the fixed sheave 62 on the primary side and the movable sheave 63 and between the fixed sheave 65 on the secondary side and the movable sheave 66. To be).

  In the continuously variable transmission 6, the hydraulic pressure control unit 7 supplies the hydraulic chamber of the primary pulley 61 (primary hydraulic chamber 68 and clamping hydraulic chamber 69 described later) and the hydraulic chamber of the secondary pulley 64 (secondary hydraulic chamber 71 described later). The primary side movable sheave 63 and the secondary side movable sheave 66 sandwich the winding member 67 between the primary side fixed sheave 62 and the secondary side fixed sheave 65 according to the hydraulic pressure (primary pressure, secondary pressure) It is possible to control (clamping pressure: clamping force). Thereby, in each of the primary pulley 61 and the secondary pulley 64, the width of the V groove can be changed to adjust the rotation radius (wrapping diameter) of the winding member 67, which corresponds to the input rotation speed of the primary pulley 61. The gear ratio, which is the ratio between the input rotational speed (primary rotational speed) and the output shaft rotational speed (secondary rotational speed) corresponding to the output rotational speed of the secondary pulley 64, can be changed steplessly. Further, by adjusting the clamping pressure of the winding member 67 of the primary pulley 61 and the secondary pulley 64, it is possible to transmit power with a torque capacity corresponding to this.

  The specific configuration of continuously variable transmission 6 in the present embodiment will be described later.

  The power transmitted to the secondary shaft Ss in the continuously variable transmission 6 is transmitted to the differential gear 10 via the gear 8 and the gear 9. The differential gear 10 transmits the transmitted power to the drive wheels 11a and 11b via each drive shaft. The differential gear 10 absorbs the rotational speed difference between the drive wheels 11a and 11b that occurs when the vehicle 1 turns.

  With the configuration described above, in the vehicle 1, the power generated by the engine 2 is transmitted to the drive wheels 11 a and 11 b via the torque converter 4, the forward / reverse switching mechanism 5, the continuously variable transmission 6, the differential gear 10, and the like. Can do. As a result, the vehicle 1 can travel by driving force [N] generated on the contact surface with the road surface of the drive wheels 11a and 11b.

The hydraulic control unit 7 uses the hydraulic oil pressure to lock the clutch 4d of the torque converter 4, the forward clutch CL and the reverse brake BR of the forward / reverse switching mechanism 5, the primary movable sheave 63 and the secondary movable sieve of the continuously variable transmission 6. The power transmission mechanism 3 including 66 and the like is operated.
The hydraulic control unit 7 includes a plurality of oil passages, an oil reservoir, an oil pump, a plurality of electromagnetic valves, and the like, and is supplied to each part of the power transmission mechanism 3 according to a signal from the transmission mechanism control unit 13. Control hydraulic oil flow rate and hydraulic pressure. The hydraulic control unit 7 also functions as a lubrication / cooling oil supply device that lubricates and cools a predetermined portion of the power transmission mechanism 3.

  The engine control unit 12 and the transmission mechanism control unit 13 include a microcomputer including a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), and the like, and a CAN (Controller Area Network). Are connected to each other via a bus 14 corresponding to a predetermined in-vehicle network communication standard.

The engine control unit 12 performs various operation controls such as fuel injection control, ignition control, and intake air amount adjustment control for the engine 2. Specifically, various operation controls for the engine 2 are performed by controlling various actuators (for example, a throttle actuator that drives a throttle valve, an injector that performs fuel injection, etc.) provided in the engine 2.
The engine control unit 12 communicates with the transmission mechanism control unit 13 and outputs data relating to the operating state of the engine 2 to the transmission mechanism control unit 13 as necessary. Further, if necessary, the operation control of the engine 2 is performed based on various signals from the transmission mechanism control unit 13.

  The transmission mechanism control unit 13 controls the operation of each part of the power transmission mechanism 3 such as the torque converter 4, the forward / reverse switching mechanism 5, and the continuously variable transmission 6 by controlling the hydraulic control unit 7.

Here, the vehicle 1 of the present example switches the range in the power transmission mechanism 3, specifically, a parking range (hereinafter referred to as “P range”), a reverse range (hereinafter referred to as “R range”), a neutral range ( Hereinafter, it is configured to be able to switch between “N range” and drive range (hereinafter referred to as “D range”).
The above range is switched in response to an operation via a range selection operator such as a shift lever (not shown) provided in the vehicle 1, and the P range is a range for stopping the vehicle 1, R The range is a range for causing the vehicle 1 to travel backward (reverse), the N range is a range for interrupting transmission of power to the continuously variable transmission 6, and the D range is a range for causing the vehicle 1 to travel forward. The P range and the N range correspond to the non-traveling range, and the R range and the D range correspond to the traveling range.

Engagement / release of the forward clutch CL and the reverse brake BR in the forward / reverse switching mechanism 5 is selected as an engagement oil path for the forward clutch CL and an engagement oil path for the reverse brake BR in conjunction with the operation of the range selection operator. It is controlled by a manual valve that supplies hydraulic pressure.
Specifically, in the P range and the N range, the manual valve sets both the engagement oil passages to the hydraulic pressure supply stop state, and sets both the forward clutch CL and the reverse brake BR to the released state. Further, in the R range, the forward passage CL is disengaged by engaging the oil passage for engaging the forward clutch CL, the hydraulic passage is engaged for the oil passage for engaging the reverse brake BR, and the reverse brake BR is engaged. Let me. Further, in the D range, the forward passage CL is engaged and the forward brake CL is disengaged by setting the oil passage for engagement of the forward clutch CL to the hydraulic supply state and the engagement oil passage of the reverse brake BR to the hydraulic supply stop state. Let me.

<2. Configuration of forward clutch as conventional example>
First, prior to the description of the forward clutch CL, which is a friction engagement device as an embodiment according to the present invention, the forward clutch CL ′ treated as a conventional example in the present invention will be described with reference to the schematic diagram of FIG. In FIG. 2, the configuration of the forward clutch CL ′ is schematically represented by a longitudinal sectional view cut along the rotational axis of the forward clutch CL ′. The configuration below the rotational shaft is the same as the configuration shown in the figure. The illustration is omitted because it is an axis object.
Note that the axial direction of the forward clutch CL ′ coincides with the longitudinal direction of the vehicle.

  The conventional forward clutch CL ′ includes a friction portion 101 having a plurality of friction plates as a drive plate 102 and a driven plate 103, a piston 104 that is hydraulically driven to engage the plurality of friction plates, and a hydraulic drive of the piston 104. The return spring 105 urged in the direction opposite to the direction, the clutch drum 107 as an outer member for connecting the input shaft 106 and the drive plate 102, and the driven plate 103 are connected, and the friction portion 101 is engaged. A clutch hub 108 for transmitting the power input via the friction part 101 to the subsequent stage, a retaining plate 109 disposed behind the friction part 101, and a snap ring 110 disposed behind the retaining plate 109, And is configured as a wet multi-plate clutch.

In the friction part 101, the drive plates 102 and the driven plates 103 are alternately arranged in the axial direction of the forward clutch CL.
The drive plate 102 is spline engaged with the clutch drum 107 so as to be displaceable in the axial direction. The clutch drum 107 is coupled to the input shaft 106 so as to be integrally rotatable, and is connected to the first cylindrical portion 107a protruding from the input shaft 106 in the direction orthogonal to the axis and the rear end of the first cylindrical portion 107a. The drive plate 102 is spline-engaged with the inner circumferential surface of the second cylindrical portion 107b and can rotate in conjunction with the clutch drum 107. It is said.
A retaining plate 109 and a snap ring 110 are fixed in order from the front to the rear at a position behind the friction portion 101 in the second cylindrical portion 107b. The snap ring 110 restricts the rearward movement of the drive plate 102 and the driven plate 103.
The driven plate 103 is spline-engaged with the clutch hub 9 so as to be axially displaceable, and is rotatable in conjunction with the clutch hub 103.

  The piston 104 has a cylindrical portion 104a at least partially positioned in the first cylindrical portion 107a of the clutch drum 107, and extends from the rear end of the cylindrical portion 104a in a flange shape in the direction perpendicular to the axis. And a pressing portion 104b positioned in the two cylindrical portions 107b. The outer diameter of the cylindrical portion 104a of the piston 104 is slightly smaller than the inner diameter of the first cylindrical portion 107a, and the outer peripheral surface can slide on the inner surface of the first cylindrical portion 107a.

  The return spring 105 is positioned in the cylindrical portion 104a of the piston 104, and one end thereof is supported from the input shaft 106 side so that the biasing direction is directed forward, and biases the piston 104 forward.

The first cylindrical portion 107a of the clutch drum 107 is configured as a hydraulic chamber for hydraulically driving the piston 104, and the piston 104 resists the biasing force of the return spring 104 by supplying a predetermined hydraulic pressure to the hydraulic chamber. And pushed backwards.
As a result, the drive plate 102 and the driven plate 103 are frictionally engaged with each other in the friction portion 101, and the forward clutch CL ′ is engaged.
On the other hand, when the hydraulic pressure supply is stopped, the piston 104 is returned to the front by the urging force of the return spring 105, the friction engagement state between the drive plate 102 and the driven plate 103 is released in the friction portion 101, and the forward clutch CL ' Released state.

<3. Configuration of forward clutch as embodiment>
As described above, in the conventional forward clutch CL ′, it is necessary to displace the piston 104 in the axial direction of the forward clutch CL ′ for engagement / release. Therefore, an axial space for reciprocating the piston 104 is required, which leads to an increase in size in the axial direction.

  Therefore, in this embodiment, the forward clutch CL is configured as follows to reduce the size in the axial direction.

FIG. 3 schematically shows the outline of the configuration of the forward clutch CL by a cross-sectional view similar to FIG.
In this example, the axial direction of the forward clutch CL coincides with the longitudinal direction of the vehicle 1.
The forward clutch CL includes a clutch drum 21 that rotates integrally with an input shaft 20 to which power from the engine 2 is transmitted via the torque converter 4, and a clutch hub 22 that is at least partially located on the front end side. And a wedge portion that is located in a region that is the outer periphery of the clutch hub 22 and that is the inner periphery of the clutch drum 21, and that is gradually reduced in thickness in the axial direction toward the outer periphery and protrudes in a substantially V-shape. A plurality of first engagement carriers 23 having 23a, and a recess 24a which is provided on the clutch drum 21 and is gradually reduced in thickness in the axial direction toward the protruding direction of the wedge portion 23a and is recessed in a substantially V shape. A second engagement carrier 24, a plurality of pistons 25 for pressing each first engagement carrier 23 in the direction perpendicular to the axis, and a retainer fixed to the rear end of the clutch drum 21 And a training plate 26 and the snap ring 27.
Here, the input shaft 20, the clutch drum 21, and the clutch hub 22 have coaxial rotation axes, and these rotation axes serve as the rotation axis Ax of the forward clutch CL. The expression “axis” refers to the rotation axis Ax unless otherwise specified.

  The clutch drum 21 has a flange portion 21a extending in a flange shape from the input shaft 20 in the outer peripheral direction, and an extended portion 21b extending rearward from the outer peripheral end of the flange portion 21a. The extending part 21b covers the clutch hub 22 arranged on the inner side over the entire circumference in the axial direction, and the clutch hub 22 and the extending part 21b have a relationship between the “inner member” and the “outer member” in the claims. It is in.

  The first engagement carriers 23 are radially arranged around the rotation axis Ax in the direction around the axis. In this example, a plurality of sets of the first engagement carriers 23 arranged in this manner are arranged in the axial direction. Has been. Hereinafter, the set of the first engagement carriers 23 arranged radially is referred to as “wedge row Kr”. FIG. 3 shows an example in which four wedge rows Kr are arranged in the axial direction.

  In the wedge portion 23a of the first engagement carrier 23, the front slope S1 is inclined forward and the rear slope S2 is inclined backward.

Further, the first engagement carrier 23 of the present example has a pedestal portion 23 b as a portion that receives the pressing force from the piston 25. The pedestal portion 23b is formed at an end opposite to the protruding direction of the wedge portion 23a, is a substantially disk-shaped portion whose thickness direction coincides with the axial orthogonal direction, and protrudes at least in the axial direction from the wedge portion 23a. (In this example, it protrudes in both the forward direction and the backward direction).
The pedestal portion 23b of this example has a function of restricting the movement of the first engagement carrier 23 in the inner peripheral direction when it is brought into contact with the outer peripheral surface of the clutch hub 22.

  The first engagement carrier 23 is attached to the clutch hub 22 so as to be displaceable in the direction perpendicular to the axis via a biasing member 42 (not shown in FIG. 3), which will be described later.

The second engagement carrier 24 includes a plurality of friction plates 24 b that protrude inward from the inner peripheral surface of the extending portion 21 b of the clutch drum 21. In this example, the friction plate 24b is formed in a ring shape coaxial with the rotation axis Ax.
In the second engagement carrier 24, the plurality of friction plates 24b are alternately arranged with the wedge portions 23a of the first engagement carrier 23 in the axial direction. At this time, the foremost friction plate 24b is positioned in front of the foremost first engagement carrier 21, and the foremost friction plate 24b is in the rear of the foremost first engagement carrier 21. Is located. In this example, there are four wedge plates Kr of the first engagement carrier 21, and therefore five friction plates 24b are provided.

In the second engagement carrier 24, the rear surface facing the slope S1 of the first engagement carrier 21 is a slope S3 inclined downward and the front surface facing the slope S2 is a slope S4 inclined downward. ing. Between the friction plates 24b adjacent to each other in the axial direction, a space is formed between the slope S3 of the front friction plate 24b and the slope S4 of the rear friction plate 24b, and the space is recessed in a substantially V shape. 24a.
The friction plate 24b positioned at the foremost end does not need to have the slope S3, and the friction plate 24b positioned at the rearmost end does not need to have the slope S4.

As shown in FIG. 4 as an angle θ, in this example, the slopes S1 and S2 of the wedge portion 23a and the slopes S3 and S4 of the friction plate 24b are all matched.
In addition, it is not necessary for all the inclination angles of the slopes S1 to S4 to coincide with each other, and it is sufficient that the inclination angles coincide with each other at least in the pair of the slope S1 and the slope S3 and the pair of the slope S2 and the slope S4.

In FIG. 3, a hydraulic cylinder 22a extending in the direction perpendicular to the axis is provided for each first engagement carrier 23 in the front end portion of the clutch hub 22, and in the vicinity of the outer peripheral end portion in the hydraulic cylinder 22a. Substantially cylindrical pistons 25 are respectively disposed.
In addition, it is not essential to provide the hydraulic cylinder 22a for each first engagement carrier 23, and a configuration in which a common hydraulic cylinder 22a is provided for the plurality of first engagement carriers 23 may be employed.

  The hydraulic cylinder 22a is supplied with an engagement hydraulic pressure for the forward clutch CL via an engagement oil passage yo formed inside the clutch hub 22. When the hydraulic pressure for engagement with a predetermined pressure is supplied to each hydraulic cylinder 22a, each piston 25 presses the corresponding first engagement carrier 23 in the outer peripheral direction (outward direction in the axis orthogonal direction). Thereby, the wedge part 23a of each 1st engagement carrier 23 engages with the corresponding recessed part 24a in the 2nd engagement carrier 24, and it frictionally engages with the friction plate 24b arrange | positioned each front and back.

At this time, the contact angle between the slope S1 and the slope S3, the slope S2 and the slope S4 can be increased and the engagement force can be increased by matching the slope angles of the slope S1 and the slope S3 and the slope S2 and the slope S4. Can be increased.
When the supply of the engagement hydraulic pressure to the engagement oil passage yo is stopped to release the forward clutch CL, the first engagement carrier 23 is moved in the inner circumferential direction by an urging member 42 described later. Returned.

  In the forward clutch CL of the embodiment, since the driving / urging direction of the first engagement carrier 23 is the axial orthogonal direction, an element that reciprocates in the axial direction such as the piston 104 in the forward clutch CL ′ is provided. There is no need to reduce the size of the forward clutch CL in the front-rear direction.

Here, FIG. 3 shows an example in which the centers of the first engagement carriers 23 in the direction around the axis coincide with each other between adjacent wedge rows Kr.
FIG. 5 schematically shows the state of the wedge row Kr corresponding to FIG. 3 with the left-right direction on the paper as the axial direction and the vertical direction on the paper as the front-rear direction (axial direction). In the drawing, a vertical broken line shown for each first engagement member 23 represents the center of the first engagement carrier 23 in the direction around the axis.

  When the centers of the first engagement carriers 23 are made to coincide with each other between the adjacent wedge rows Kr as shown in FIG. 5, the first engagement in the front-rear direction is performed in order to prevent buffering between the base portions 23 b. It is necessary to relatively widen the arrangement interval between the carriers 23.

Therefore, as shown in FIG. 6, it is possible to adopt a configuration in which the centers of the first engagement carriers 23 in the axial direction between the adjacent wedge rows Kr are separated in the axial direction.
Thereby, even if the arrangement interval of the wedge row Kr is narrower than in the case of FIG. 5, it is possible to prevent the pedestal portions 23b from buffering. That is, the arrangement interval of the wedge rows Kr can be easily narrowed, and thereby the size of the forward clutch CL in the axial direction can be further reduced.

With reference to FIG. 7 thru | or FIG. 13, the structure which concerns on the attachment to the clutch hub 22 of the 1st engagement carrier 23 is demonstrated.
7 and 8 are an external view of the first engagement carrier 23 as viewed from the side facing the tip of the wedge portion 23a, and an external view of the first engagement carrier 23 as viewed from the front side. FIG.
7 to 9, the two attachment portions 41 provided on the clutch hub 22 side, the hydraulic cylinder 22a, and the piston 25 are shown together by broken lines.

The first engagement carrier 23 includes a front member 31 having a slope S1, a rear member 32 having a slope S2, and a front member 31 and a rear member 32 that are inserted in the front-rear direction of the first engagement carrier 23. It has a rod-shaped locking member 33 that locks, for example, with a rivet (see FIGS. 7 and 9).
In addition to the rivets, other rod-shaped locking members such as bolts and knock pins can be used as the rod-shaped locking members 33.

The front member 31 is formed with a slope S1 and forms a half wedge 31a that forms the front half of the wedge 23a, a half pedestal 31b that forms the front half of the pedestal 23b, and a half wedge 31a in the direction perpendicular to the axis. A semi-intermediate portion 31c is formed which is located in the middle of the half pedestal portion 31b and whose length in the axial direction is shorter than the half wedge portion 31a (see FIGS. 8 and 9).
The rear member 32 is formed with a slope S2 and has a half wedge portion 32a constituting the rear half of the wedge portion 23a, a half pedestal portion 32b constituting the rear half of the pedestal portion 23b, and a half wedge portion 32a in the direction perpendicular to the axis. And a half-intermediate portion 32c that is located in the middle of the half pedestal portion 32b and has a shorter length in the axial direction than the half-wedge portion 32a.
In the first engagement carrier 23, a portion formed by the half-intermediate portion 31c and the half-intermediate portion 32c is hereinafter referred to as “intermediate portion 23c”.

  Here, two attachment portions 41 are formed on the outer peripheral surface of the clutch hub 22 for each first engagement carrier 23. These attachment portions 41 are arranged on both sides of the piston 25 in the direction around the axis, and are positioned in the first engagement carrier 23 when the first engagement carrier 23 is attached to the clutch hub 22 via the attachment portion 41. ing.

FIG. 10 is a cross-sectional view of the first engagement carrier 23 attached to the clutch hub 22 via the attachment portion 41, taken along the line AA ′ shown in FIG. FIG. 12 is an exploded cross-sectional view of the first engagement carrier 23 and a cross-section of the mounting portion 41 taken along line AA ′.
In FIG. 10, the positions of the hydraulic cylinder 22a and the piston 25 in the front-rear direction are indicated by broken lines. In FIG. 11, the urging member 42 positioned inside the mounting portion 41 is represented by a broken line, and the rod-like locking member 33 is not illustrated in FIG. 12.

The front member 31 and the rear member 32 are respectively formed with a storage recess 31e recessed toward the front of the contact surface between the front member 31 and the rear member 32, and a storage recess 32e recessed toward the rear. When the combined carrier 23 is attached to the clutch hub 22, the entire attachment portion 41 is accommodated in a space formed inside the first engagement carrier 23 by the storage recess 31 e and the storage recess 32 e.
Further, the front member 31 has an insertion hole 31d penetrating from the front surface of the semi-intermediate portion 31c to the storage recess 31e in the front-rear direction, and the rear member 32 is extended from the rear surface of the semi-intermediate portion 32c to the storage recess 32e in the front-rear direction. An insertion hole 32d penetrating therethrough is formed.

  The attachment portion 41 is formed with a storage hole 41a for storing the biasing member 42 therein, and a through hole 41b penetrating in the front-rear direction. The storage hole 41a is located closer to the clutch hub 22 than the through hole 41b, and penetrates from the end of the mounting portion 41 on the clutch hub 22 side to the through hole 41b.

  The urging member 42 is, for example, a coil spring, a part thereof is accommodated in the accommodation hole 41a, and one end is fixed to the clutch hub 22 side.

The rod-shaped locking member 33 is inserted through the insertion hole 31 d of the front side member 31, the through hole 41 b of the attachment portion 41, and the insertion hole 32 d of the rear side member 32.
The other end of the biasing member 42 is fixed in the through hole 41b with respect to the rod-shaped locking member 33 inserted through the insertion hole 31d, the through hole 41b, and the insertion hole 32d.

  The first engagement carrier 23 is attached to the clutch hub 22 on the other attachment portion 41 side by the same configuration as described above. At this time, the storage recess 32e and the storage recess 32e may be provided for each mounting portion 41, or each of the storage recess 32e and the storage recess 32e that can store the two mounting portions 41 may be formed.

FIG. 13 shows a state in which the first engagement carrier 23 is driven by the piston 25 as a cross-sectional view taken along the line AA ′ of FIG.
With the configuration of the first engagement carrier 23 and the mounting portion 41 described above, when the driving force by the piston 25 is applied to the first engagement carrier 23, the front side member 31 and the rear side member 32 are displaced in the outer circumferential direction. In accordance with this, the rod-like locking member 33 is displaced in the outer circumferential direction within the through hole 41b, and the biasing member 42 is also expanded in the outer circumferential direction accordingly.
When the supply of hydraulic pressure to the hydraulic cylinder 22a is stopped and the driving of the first engagement carrier 23 by the piston 25 is stopped, the urging force of the urging member 42 acts on the rod-like locking member 33, and accordingly the front side The member 31 and the rear member 32 are returned in the inner circumferential direction.

Here, in this example, since the first engagement carrier 23 is hydraulically driven from the side of the clutch hub 22 as the inner member toward the outer side, the urging member 42 has the following urging force. It is desirable. In other words, the urging member 42 generates a centrifugal force acting on the first engagement carrier 23 by rotating integrally with the clutch hub 22 and a pressing force applied to the first engagement carrier 23 due to the centrifugal hydraulic pressure. It is desirable to have a biasing force that cancels.
As a result, the first engagement carrier 23 and the second engagement carrier 24 are not engaged with each other unless hydraulic pressure is supplied to the engagement oil passage yo at a predetermined pressure.

FIG. 14 is an explanatory diagram of the tip shape of the wedge portion 23a.
In this example, the tip of the wedge portion 23a is flat. In other words, the tip of the wedge portion 23a is closer to the clutch hub 22 (inner member) than the intersection line Lc formed by intersecting the slope S1 and the slope S2, that is, a pair of slopes having a substantially V shape. Is located.
As a result, the depth of the recess 24a in the second engagement carrier 24 can be reduced, the diameter of the clutch drum 21 can be reduced, and the size of the forward clutch CL in the direction perpendicular to the axis can be reduced. Can be planned.
The tip of the wedge portion 23a is not limited to a flat shape, and other shapes such as a hemispherical shape may be employed.

<4. Modification>
In the above, an example in which the piston 25 and the first engagement carrier 23 are configured separately has been described. However, the piston 25 and the first engagement carrier 23 may be configured integrally.

  In the above description, the present invention is applied to a forward clutch of a four-wheeled vehicle. However, the clutch can be applied to a transfer clutch in a four-wheeled vehicle or a clutch in a two-wheeled vehicle. is there.

  Furthermore, in the above description, an example in which the first engagement carrier is attached to the inner member is given as an example of application to the clutch, but a configuration in which the first engagement carrier is attached to the outer member can also be adopted. In that case, at the time of friction engagement with the second engagement carrier, the first engagement carrier is pressed in the inner circumferential direction (inner direction in the direction perpendicular to the axis). Further, in the same manner as in FIG. 14, when the depth of the concave portion in the second engagement carrier is made shallow, the tip of the wedge portion is positioned closer to the inner member side than the intersection point Pc.

  The present invention is not limited to the clutch, and can be suitably applied to brake elements such as the reverse brake BR in the forward / reverse switching mechanism 5. Even in this case, the first engagement carrier can be attached to either the inner member or the outer member. In addition, when applying this invention to a brake element, either an inner side member or an outer side member is rotatable, and either one is a fixed (non-rotatable) member.

In the above description, the first engagement carrier is arranged not only in the axial direction but also in the axial direction. However, the first engagement carrier only needs to be arranged radially at least in the axial direction.
Here, the minimum arrangement number of the first engagement carrier in the direction around the axis is “2”. In the present specification, “arranged radially” can also be said to be a state in which a plurality of first engagement carriers are arranged at substantially equal intervals in the direction around the axis.
When the first engagement carriers and the second engagement carriers are frictionally engaged by pressing the first engagement carriers arranged radially to the recesses in the second engagement carrier in the direction orthogonal to the axis. The engagement force is less likely to be biased in the direction around the axis, and the stabilization of the engagement operation can be improved.

<5. Summary of Embodiment>
As described above, the friction engagement device (forward clutch CL) of the embodiment includes an inner member (clutch hub 22), an outer member (extension portion 21b) that covers the outer periphery of the inner member coaxially with the inner member, and the inner member. Are arranged radially in the direction around the axis in a region which is the outer periphery of the outer member and the inner member or the outer member. A plurality of first engaging carriers (23) having wedge portions (23a) projecting in a substantially V shape with a thickness in the axial direction gradually reduced toward either one of the outer members; Alternatively, a second engagement carrier (same as 24a) provided on either the other of the outer members and having a concave portion (24a) recessed in a substantially V shape with the thickness in the axial direction being gradually reduced toward the protruding direction of the wedge portion. 24), and each first engagement carrier is orthogonal to the axis Includes an engagement drive portion for the pressed recesses the wedge portion frictionally engaged with the second engagement carrier direction (the hydraulic cylinder 22a, a piston 25), the.

According to the above configuration, the piston that is displaced in the axial direction is not necessary when the first engagement carrier and the second engagement carrier are frictionally engaged.
Therefore, it is possible to reduce the size of the friction engagement device in the axial direction.
Further, by engaging a plurality of first engagement carriers arranged radially in the direction around the axis in the direction perpendicular to the axis, the engagement force when the first engagement carrier and the second engagement carrier are frictionally engaged. This makes it difficult for deviation in the direction around the axis to occur, and the stabilization of the engaging operation can be improved.

  Further, in the friction engagement device of the embodiment, the engagement drive unit presses the first engagement carrier based on the hydraulic pressure.

As a result, it is not necessary to add an electromagnetic actuator such as a motor or a solenoid as driving means for the first engagement carrier.
Therefore, an increase in the number of parts can be suppressed, and the apparatus size can be reduced and the cost can be reduced.

  Furthermore, in the friction engagement device of the embodiment, the first engagement carrier is attached to the inner member, and the engagement drive unit has an engagement oil passage (same as the above) formed in the inner member. The first engagement carrier is pressed in the outer circumferential direction based on the hydraulic pressure of the engagement oil passage.

Since the inner member is smaller in diameter than the outer member, the first engagement carrier is attached to the inner member as described above, and the engagement oil passage is provided in the inner member. It becomes easy to reduce the volume.
Accordingly, the amount of hydraulic oil required for friction engagement can be reduced, the total amount of hydraulic oil in the vehicle can be reduced, and the vehicle weight associated therewith can be reduced, thereby improving fuel efficiency.

  Furthermore, the friction engagement device of the embodiment includes an urging member (42) for urging the first engagement carrier in the inner circumferential direction, and the inner member is a rotatable member. The member has a biasing force that cancels the centrifugal force acting on the first engagement carrier by rotating integrally with the inner member and the pressing force applied to the first engagement carrier due to the centrifugal hydraulic pressure. Yes.

As a result, the first engagement carrier and the second engagement carrier are not engaged unless the hydraulic pressure is supplied to the engagement oil passage at a predetermined pressure.
Therefore, it is possible to prevent erroneous engagement from occurring with the rotation of the inner member, and to improve the operational stability of the friction engagement device.

  In the friction engagement device of the embodiment, a plurality of wedge rows in which the first engagement carriers are radially arranged are arranged in the axial direction, and the first engagement carriers are arranged between adjacent wedge rows. The centers in the axial direction are spaced apart in the axial direction.

Thereby, when each first engagement carrier has a pedestal portion protruding in the axial direction from the wedge portion, the arrangement interval in the axial direction of the wedge row is reduced while preventing the pedestal portions from being buffered. Is possible.
Therefore, further size reduction in the axial direction of the friction engagement device can be achieved.

  Furthermore, in the friction engagement device of the embodiment, in the first engagement carrier, the tip of the wedge portion is an inner member or an inner line with respect to an intersection line formed by intersecting a pair of inclined surfaces having a substantially V shape. It is located on either side of the outer member.

  Thereby, since the depth of the recessed part in a 2nd engagement carrier can be made shallow, size reduction in the radial direction of a friction engagement apparatus can be achieved.

  DESCRIPTION OF SYMBOLS 1 Vehicle, 4 torque converters, 5 forward / reverse switching mechanism, Ps primary shaft, Ss secondary shaft, 20 input shaft, 21 clutch drum, 21a flange part, 21b extension part, 22 clutch hub, 22a hydraulic cylinder, yo engagement oil Road, 23 First engagement carrier, 23a Wedge part, 23b Pedestal part, 23c Intermediate part, Kr Wedge row, 24 Second engagement carrier, 24a Recessed part, 24b Friction plate, 25 Piston, S1-S4 slope, 41 Attachment part 42 Energizing member, Lc

Claims (6)

A friction engagement device in a vehicle,
An inner member;
An outer member covering the outer periphery of the inner member coaxially with the inner member;
In the region that is the outer periphery of the inner member and the inner periphery of the outer member, the inner member is radially arranged in the direction around the axis, and is attached to either the inner member or the outer member so as to be displaceable in the direction perpendicular to the axis And a plurality of first engagement carriers having wedge portions that are gradually reduced in thickness in the axial direction toward the other of the inner member or the outer member and project in a substantially V shape,
A second engagement carrier provided on either the inner member or the outer member, and having a recess recessed in a substantially V shape with a thickness in the axial direction gradually reduced toward the protruding direction of the wedge portion; ,
A friction engagement device comprising: an engagement drive unit that presses each first engagement carrier in a direction orthogonal to the axis and frictionally engages the wedge portion with the second engagement carrier in the recess. The friction engagement device according to claim 1, wherein the engagement driving unit presses the first engagement carrier based on hydraulic pressure. The first engagement carrier is attached to the inner member;
The engagement drive unit is
The friction engagement device according to claim 2, further comprising an engagement oil passage formed in the inner member and pressing the first engagement carrier in an outer peripheral direction based on a hydraulic pressure of the engagement oil passage. A biasing member for biasing the first engagement carrier in the inner circumferential direction;
The inner member is a rotatable member,
The biasing member is
The urging force that cancels out the centrifugal force acting on the first engagement carrier by rotating integrally with the inner member and the pressing force applied to the first engagement carrier due to centrifugal hydraulic pressure. 3. The friction engagement device according to 3. A plurality of wedge rows in which the first engagement carriers are arranged radially are arranged in the axial direction,
The friction engagement device according to any one of claims 1 to 4, wherein centers of the first engagement carriers in an axial direction between the adjacent wedge rows are separated in an axial direction. In the first engagement carrier,
The front end of the wedge portion is positioned on either one side of the inner member or the outer member with respect to an intersection line formed by intersecting the pair of inclined surfaces having a substantially V shape. The friction engagement device according to any one of claims 1 to 5.

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