JP5869255B2 - Driving force connection / disconnection device - Google Patents

Description

The present invention relates to a driving force connecting / disconnecting device for connecting / disconnecting driving force by arranging it in a driving force transmitting device for a four-wheel driving vehicle capable of switching between two-wheel driving and four-wheel driving, and in particular, driving force with small power. The present invention relates to a driving force connecting / disconnecting device capable of connecting / disconnecting.

  As a conventional driving force connecting / disconnecting device that is arranged in a driving force transmission device for a four-wheel drive vehicle and switches between two-wheel driving and four-wheel driving by connecting / disconnecting driving force, for example, 2 described in Patent Document 1 There is a wheel / four wheel drive switching device.

  Such a switching device is provided with a waiting mechanism using a spring, and when the driving force is connected, if the phase of the main driving side and the driven side of the connecting / disconnecting mechanism does not match, the actuator accumulates the spring by the actuator such as a motor. When it is right, the accumulated power is released and the connection / disconnection mechanism is connected.

  In Patent Document 1, when switching from two-wheel drive to four-wheel drive, if the phase of the spline of the transmission side output shaft and the spline of the driven wheel side output shaft does not match, When the spline is in phase, the slider that has stopped on the transmission side output shaft engages with the spline of the driven wheel side output shaft by the accumulated torsion spring, and the transmission side output shaft and the driven wheel side output shaft Is connected.

  Further, as a driving force connecting / disconnecting device for switching between two-wheel driving and four-wheel driving by connecting / disconnecting transmission of driving force between the axle and the wheel hub, for example, an actuator such as a motor described in Patent Document 2 is incorporated. There is an electric freewheel hub device.

  Such an electric freewheel hub device connects the connection / disconnection mechanism with a built-in motor when switching from two-wheel drive to four-wheel drive, but the rotational speed between the axle and the wheel hub, that is, the front wheel and the rear wheel. Can be connected only when the rotational speeds coincide with each other. Therefore, it is impossible to reliably switch from the two-wheel drive to the four-wheel drive while the vehicle is running.

Therefore, in Patent Document 2, the driving force transmission device is provided with a synchronizing means for synchronizing the rotation of the front and rear wheels, and the electric freewheel hub device is provided with a delay means for energizing the actuator after the rotation of the front and rear wheels is synchronized. It is possible to reliably switch from 2-wheel drive to 4-wheel drive while the vehicle is running.

JP 63-87317 A Japanese Utility Model Publication No. 03-53640

  However, in the conventional driving force connecting / disconnecting devices as described in Patent Documents 1 and 2, when switching from four-wheel drive to two-wheel driving, an actuator is operated to disconnect the driving force connecting / disconnecting device. However, when torque is applied between the input and output shafts of the driving force connecting / disconnecting device (torque is accumulated), it cannot be disconnected, and the four-wheel drive state is maintained until the torque does not operate (torque is released). There is a problem that it will remain.

  In addition, as a countermeasure to this problem, if the driving force connecting / disconnecting device is forcibly disconnected without waiting for the torque transmission between the input / output shafts of the driving force connecting / disconnecting device to be lost, the connecting / disconnecting mechanism is operated. Therefore, since a large amount of power is required, there is a problem that the actuator is increased in size and cost.

The present invention is a low-cost driving force connecting / disconnecting device that can cut a driving force with a small amount of power by connecting / disconnecting the input / output shaft using the driving force transmitted between the input / output shafts of the driving force connecting / disconnecting device. The purpose is to provide.

In order to achieve this object, the driving force connecting / disconnecting device according to the present invention is configured as follows. The present invention relates to a driving force connecting / disconnecting device in which a first shaft for inputting / outputting a driving force and a second shaft are arranged coaxially to be connected and released, and a first cam member rotatably supported by the first shaft; A second cam member that rotates with the second shaft and is movable between a position where the first cam member is cut and connected with the first shaft, and the second cam member is connected to the first shaft. An urging member that presses in the direction to rotate, a brake mechanism that brakes rotation of the first cam member and relatively rotates the first cam member and the second cam member, and operates when the first cam member is rotating And a check mechanism for restricting the range of relative rotation.

Here, when the second cam member is in a position where the second cam member is cut or connected to the first shaft, the first cam member is relatively stationary with respect to the second cam member by pressing of the biasing member , and the second cam member is When the brake mechanism is actuated when it is in a position to be disconnected from the first shaft, it is pressed by the urging member to move to a position to be connected to the first shaft, and is in a position to be connected to the first shaft When the brake mechanism is actuated, it moves to a position where it is disconnected from the first shaft against the pressing of the urging member, and the check mechanism is moved to a position where the second cam member is disconnected from the position where it is connected to the first shaft. When moved, the relative rotation is restricted and the second cam member is held at the cutting position . The check mechanism is operated by a centrifugal force acting on the first cam member.

According to the present invention, the cam member provided on each of the input / output shafts of the driving force connecting / disconnecting device is rotated relative to each other by operating the brake mechanism, thereby utilizing the driving force transmitted between the input / output shafts. The input / output shaft can be connected or disconnected. Therefore, the driving force can be connected / disconnected with a small amount of power for operating the brake mechanism, and the driving force connecting / disconnecting device for switching between two-wheel drive and four-wheel drive can be reduced in size and cost.

Explanatory drawing which shows 1st Embodiment of the driving force transmission device for four-wheel drive vehicles which has arrange | positioned the driving force connection / disconnection apparatus by this invention. Sectional drawing which shows embodiment of the front-wheel drive part of FIG. Explanatory drawing which takes out the driving force connection / disconnection device of FIG. 2 and shows in detail Explanatory drawing which takes out the check mechanism of FIG. 3, and shows it in detail Sectional drawing which shows embodiment of the rear-wheel drive part of FIG. 1, and a rotation difference sensitive type coupling Explanatory drawing which shows the state at the time of two-wheel drive mode of the driving force connection / disconnection apparatus of FIG. Explanatory drawing which shows the state at the time of switching from 2 wheel drive mode to 4 wheel drive mode of the driving force connection / disconnection apparatus of FIG. Explanatory drawing which shows the state at the time of switching from 2 wheel drive mode to 4 wheel drive mode of the driving force connection / disconnection apparatus of FIG. Explanatory drawing which shows the state at the time of four-wheel drive mode of the driving force connection / disconnection apparatus of FIG. Explanatory drawing which shows the state at the time of switching from the four-wheel drive mode to the two-wheel drive mode of the driving force connection / disconnection device of FIG. Explanatory drawing which shows the state at the time of the switching from the four-wheel drive mode to the two-wheel drive mode of the driving force connection / disconnection device of FIG. Explanatory drawing which shows 2nd Embodiment of the driving force transmission device for four-wheel drive vehicles which has arrange | positioned the driving force connection / disconnection apparatus by this invention. Explanatory drawing which shows 3rd Embodiment of the driving force transmission apparatus for four-wheel drive vehicles which has arrange | positioned the driving force connection / disconnection apparatus by this invention.

  Hereinafter, the driving force connecting / disconnecting device of the present invention will be described in detail with reference to the drawings showing embodiments. In the following embodiments, an on-demand full-time mode capable of switching between a two-wheel drive mode in which only the main drive wheel is driven and a four-wheel drive mode in which the main drive wheel is always driven and the auxiliary drive wheel is driven as necessary. A four-wheel drive vehicle is shown as an example.

  Each embodiment is a four-wheel drive vehicle based on an FF (Front-engine Front-drive) vehicle that drives the front wheels in the two-wheel drive mode, or an FR (Front-engine Rear-drive) that drives the rear wheels in the two-wheel drive mode. ) A vehicle-based four-wheel drive vehicle, and at least the engine and the driving force transmission device are controlled by an ECU (Electronic Control Unit) based on detection values of various vehicle state detection sensors.

  FIG. 1 is an explanatory view showing a first embodiment of a driving force transmission device for a four-wheel drive vehicle in which a driving force connecting / disconnecting device according to the present invention is arranged, and is applied to a four-wheel drive vehicle based on an FF vehicle. is there.

  In FIG. 1, the driving force transmission device 12 of this embodiment is provided in a four-wheel drive vehicle 10 and includes a front wheel driving unit 14, a driving force transmission unit 16, and a rear wheel driving unit 18. The driving device 20 and the driving force transmission unit 16 are provided with a rotation-sensitive coupling 28, and the rear wheel driving unit 18 is provided with a rear wheel differential device 22.

  A first switching device 24 is provided between the front wheel differential device 20 and the driving force transmission unit 16, and a second switching device 26 is provided between the rear wheel differential device 22 and the right rear wheel 86. The first switching device 24 includes a driving force connecting / disconnecting device 54 according to the present invention, and the second switching device 26 includes a synchronization mechanism 78 and a meshing clutch mechanism 80, and includes a first actuator 56 and a second actuator 82, respectively. Can be switched between a disconnected state in which the two-wheel drive mode is set and a connected state in which the four-wheel drive mode is set.

  Control signals E 1 and E 2 from the ECU 30 are given to the first actuator 56 of the first switching device 24 and the second actuator 82 of the second switching device 26. The driving force from the engine 32 is shifted by the transmission 34 and then input from the drive gear 36 of the transmission 34 to the ring gear 38 of the front wheel differential 20, and the front wheel differential 20 is driven from the transmission 34. The force is transmitted to the left front wheel 46 and the right front wheel 48.

  The front wheel differential device 20 absorbs the rotational speed difference and generates a torque equal to the left front wheel 46 and the right front wheel 48 when a difference in rotational speed occurs between the left front wheel 46 and the right front wheel 48 during cornering or due to a change in road surface condition. To rotate.

  The driving force from the drive gear 36 is also input to the first switching device 24 via the ring gear 38 and the differential case 40 of the front wheel differential device 20, and the first switching device 24 from the ECU 30 in the two-wheel drive mode. The first actuator 56 is actuated by the control signal E1 to disconnect the driving force transmission unit 16, and the driving force for the rear wheel side is disconnected.

  For this reason, the driving force from the transmission 34 is transmitted to the differential case shaft 50 via the ring gear 38 and the differential case 40 of the front wheel differential device 20, but the ring gear shaft 52 because the first switching device 24 is in a disconnected state. Is not output.

  On the other hand, since the second switching device 26 is also disconnected by the control signal E2 from the ECU 30, the ring gear 70 of the rear wheel differential 22 is rotated even if the left rear wheel 84 and the right rear wheel 86 are rotating. do not do.

  Thus, in the two-wheel drive mode, the ring gear 58, the output pinion 60, the universal joint 62, the propeller shaft 64, the universal joint 66, the rotation-sensitive coupling 28, the drive pinion 68, and the ring of the rear wheel differential 22 The driving force transmission unit 16 including the gear 70 stops rotating, and the problem that the fuel consumption is reduced due to friction loss caused by the rotation of the driving force transmission unit 16 in the two-wheel drive mode can be solved.

  On the other hand, in the four-wheel drive mode, the first switching device 24 is connected to the driving force transmission unit 16 by operating the first actuator 56 in response to the control signal E1 from the ECU 30. Therefore, the driving force input to the first switching device 24 is transmitted from the differential case shaft 50 rotating integrally with the differential case 40 to the ring gear shaft 52, and the ring gear 58 and output pinion 60 rotating integrally with the ring gear shaft 52. And the direction of transmission is changed.

  The driving force output from the output pinion 60 is transmitted to the drive pinion 68 via the universal joint 62, the propeller shaft 64, the universal joint 66, and the rotation-sensitive coupling 28, and from the drive pinion 68 to the rear wheel differential device 22. The direction is transmitted to the ring gear 70.

  Here, the rotation-difference type coupling does not transmit torque when there is no difference in rotational speed between the input side and the output side, but torque according to the rotational speed difference when there is a difference in rotational speed. In this embodiment, a viscous coupling is used.

  In the four-wheel drive mode, when there is no difference in rotational speed between the front wheels 46 and 48 and the rear wheels 84 and 86, the rotation-sensitive coupling 28 does not distribute the driving force to the rear wheel drive unit 18, When there is a difference in the rotational speed between the front wheels 46 and 48 and the rear wheels 84 and 86, such as when the wheel slips, that is, the driving force transmission portion 16 side of the rotation-sensitive coupling 28 and the opposite side thereof. When a rotational speed difference occurs between the rear wheel drive unit 18 and the rotation difference sensitive coupling 28, the driving force corresponding to the rotational speed difference is distributed to the rear wheel drive unit 18.

  In the two-wheel drive mode, the second switching device 26 is controlled to be disconnected by operating the second actuator 82 by the control signal E2 from the ECU 30, and the driving force between the right rear wheel 86 and the rear wheel differential device 22 is controlled. In the four-wheel drive mode, the second actuator 82 is operated by the control signal E2 from the ECU 30 to be controlled to be in the connected state, via the rotation difference sensitive coupling 28 and the rear wheel differential device 22. The driving force from the engine 32 is transmitted to the right rear wheel 86.

  In the present embodiment, as will be described with reference to FIGS. 2 and 3, the driving force connecting / disconnecting device 54 of the present invention is provided in the first switching device 24, and the synchronization mechanism 78 is provided in the second switching device 26. The mesh clutch mechanism 80 is used, and the first actuator 56 and the second actuator 82 can be operated to switch between the disconnected state in the two-wheel drive mode and the connected state in the four-wheel drive mode.

  FIG. 2 is a cross-sectional view showing the front wheel drive section 14 of FIG. In FIG. 2, the front wheel differential device 20, the first switching device 24, the ring gear 58 and the output pinion 60 are accommodated in a housing 88 connected to the transmission 34. The housing 88 is divided into a plurality of parts, each of which is fastened with a bolt.

  The front wheel differential device 20 located on the left side of the housing 88 is rotatably supported by the housing 88 on both the left front wheel drive shaft 42 side and the right front wheel drive shaft 44 side of the differential case 40 by tapered roller bearings 90 and 92, respectively. ing. A ring gear 38 that engages with the drive gear 36 of the transmission 34 is fixed to the differential case 40.

  On the right side of the housing 88, a ring gear gear shaft 52 is provided, which is non-rotatably fitted to the ring gear 58 coaxially with the differential case 40. The ring gear shaft 52 has an end on the ring gear 58 side by a double row angular bearing 94. The housing 88 is rotatably supported.

  An output pinion 60 that engages with the ring gear 58 is disposed on the lower right side of the housing 88, and the output pinion 60 is coupled to the propeller shaft 64 via a universal joint 62 that is connected to the lower side.

  Between the front wheel differential device 20 and the ring gear gear shaft 52, both sides of the front wheel differential device 20 side and the ring gear gear shaft 52 side are supported by ball bearings 96 and 98, respectively, and are connected to the differential case shaft 50 by spline. An intermediate shaft 100 that rotates integrally is provided.

  The driving force connecting / disconnecting device 54 of the present invention is provided on the outer peripheral portion of the intermediate shaft 100 and the inner peripheral portion of the ring gear shaft 52 on the front wheel differential device 20 side, and the first actuator 56 is provided above the intermediate shaft 100. Is fixed to the housing 88. The driving force connecting / disconnecting device 54 and the first actuator 56 constitute the first switching device 24.

  FIG. 3 is an explanatory view showing the driving force connecting / disconnecting device 54 of FIG. 2 in detail, and FIG. 3A is a cross-sectional view showing the connected state on the upper side of the center line of the intermediate shaft 100 and the cut state on the lower side. 3B, the upper side is in the connected state in the AA cross-sectional direction in FIG. 3A, and the lower side is in the cut state in the BB cross-sectional direction in FIG. 3A. Further, FIG. 3A shows the CC cross-sectional direction of FIG.

  As shown in FIG. 3A, the driving force connecting / disconnecting device 54 is rotatably inserted into the intermediate shaft 100 and the intermediate shaft 100 to which the driving force from the engine 32 is input via the transmission 34 and the differential case 40. The first cam member 102 having a cylindrical portion and a flange portion, the outer peripheral side is splined to the inner peripheral portion of the ring gear shaft 52 and moved in the axial direction, whereby the inner peripheral spline is engaged with the spline of the intermediate shaft 100. A removable ring-shaped second cam member 104 is provided.

  The driving force connecting / disconnecting device 54 further brakes the rotation of the coil spring (biasing member) 106 that presses the second cam member 104 against the first cam member 102 and the first cam member 102, and the first cam member 102 and the first cam member 102. A brake mechanism 108 that relatively rotates the two cam members 104 and a check mechanism 116 that regulates a range of relative rotation between the first cam member 102 and the second cam member 104 are provided.

  As shown in FIG. 3B, the first cam member 102 has a plurality of convex portions 102a arranged at equal intervals in the circumferential direction on the end surface of the flange portion on the second cam member 104 side. The cam surface is constituted by the top surface 102b, the inclined surface 102c, and the bottom surface 102d of 102a.

  The second cam member 104 has the same number of convex portions 104a arranged on the end face on the first cam member 102 side so as to face the convex portion 102a of the first cam member 102. The convex portion 104a Functions as a follower.

  Here, the top surface 104b (see FIG. 6) of the convex portion 104a contacts the bottom surface 102d of the first cam member 102 on the upper side of FIG. 3B, and the first surface on the lower side of FIG. 3B. The cam member 102 is in contact with the top surface 102b.

  The brake mechanism 108 is slidable on a plurality of friction plates 112 disposed between the outer peripheral portion of the first cam member 102 and the inner peripheral portion of the drum 110 fixed to the housing 88 and the inner peripheral portion of the drum 110. And a piston 114 that presses the friction plate 112 in conjunction with the first actuator 56. The upper side of FIG. 3A is a state where the brake mechanism 108 is operated, and the lower side of FIG. 3A is a state where the brake mechanism 108 is not operated.

  In the present embodiment, the convex portion 102a of the first cam member 102 and the convex portion 104a of the second cam member 104 are each composed of four, but the number may be other than four. The brake mechanism 108 has a configuration similar to that of a so-called multi-plate clutch mechanism, and uses an electromagnetic solenoid as the first actuator 56. However, any other system such as a single-plate clutch mechanism or a hydraulic plunger is used. It doesn't matter.

  FIG. 4 is an explanatory view showing the check mechanism 116 of FIG. 3 in detail, and shows a state where the first cam member 102 is rotated and the check mechanism 116 is operated by centrifugal force. Further, the intermediate shaft 100 and the second cam member 104 are indicated by imaginary lines.

  As shown in FIG. 4, the check mechanism 116 is provided in the lower part of the convex part 102a of the 1st cam member 102, and is comprised by the spring 120 which urges | biases the stopper pin 118 and the direction which does not protrude the stopper pin 118. Yes.

  As will be described in detail later, the first cam member 102 may or may not rotate with respect to the housing 88. When the first cam member 102 does not rotate, the stopper pin 118 biases the spring 120. The stopper pin 118 protrudes from the surface 102e when the centrifugal force due to the rotation exceeds the urging force of the spring 120, and the locking portion 104c formed below the convex portion 104a of the second cam member 104 By engaging, relative rotation between the first cam member 102 and the second cam member 104 can be restricted.

  FIG. 5 is a cross-sectional view showing the rear wheel drive unit 18 and the rotation difference sensitive coupling 28 in FIG. 1, and the upper side of the figure is the front side (forward direction) of the four-wheel drive vehicle 10. In FIG. 5, the rotation difference sensitive coupling 28, the drive pinion 68, the rear wheel differential device 22 and the second switching device 26 are accommodated in a housing 122. The housing 122 is divided into a plurality of parts, each of which is fastened with a bolt.

  In the present embodiment, a viscous coupling is used as the rotation-sensitive coupling 28. Viscous coupling is a well-known technology as a fluid clutch that utilizes the shear resistance of oil when a plurality of clutch plates provided on each of the input and output shafts rotate relative to each other in a case filled with oil. A detailed description of the configuration and operation of the differential-sensitive coupling 28 is omitted.

  In the rear wheel differential 22 located on the left side of the housing 122, both the left rear wheel drive shaft 74 side and the right rear wheel drive shaft 76 side of the differential case 72 are rotatable to the housing 122 by taper roller bearings 124 and 126, respectively. It is supported by. A ring gear 70 that is engaged with a drive pinion 68 connected to the rotation-difference-sensitive coupling 28 is fixed to the differential case 72.

  A second switching device 26 is provided on the right side of the housing 122. The second switching device 26 is engaged with the synchronization mechanism 78, a clutch mechanism 80, a shift fork 128, a shift rod 130, a pinion 132, and a servo motor (not shown). It is configured.

  In this embodiment, the meshing clutch mechanism 80 of the second switching device 26 shown in FIG. 5 uses a dog clutch system, but a spline clutch system can also be used, and other systems other than this can be used. Absent. Further, the synchronization mechanism 78 of the second switching device 26 uses a conical friction clutch system, but other systems may be used.

  Further, the shift rod 130 shown in FIG. 5 is operated by the pinion 132 engaged with the rack being driven by the servo motor, but the actuator for driving the shift rod 130 can be of any type, other than the servo motor. This method is also acceptable.

  FIG. 5 shows a state in which the second switching device 26 is connected in the four-wheel drive mode, and the meshing clutch mechanism 80 is in a meshed state, and the rear wheel differential device 22 and the right rear wheel drive shaft 76 are connected. It is in the position to do. In this state, the driving force from the drive pinion 68 engaged with the ring gear 70 can be transmitted to the left rear wheel 84 and the right rear wheel 86 via the left rear wheel drive shaft 74 and the right rear wheel drive shaft 76.

  In the two-wheel drive mode, the shift fork 128 and the shift rod 130 move to the right and the meshing clutch mechanism 80 is disengaged (illustrated by an imaginary line), and the second switching device 26 is disconnected.

  Next, switching control from the two-wheel drive mode to the four-wheel drive mode and from the four-wheel drive mode to the two-wheel drive mode in the first embodiment will be described with reference to FIGS.

  When switching from the two-wheel drive mode to the four-wheel drive mode, first, the second actuator 82 is actuated by the control signal E2 of the ECU 30, and the second switch device 26 is synchronized, that is, the rear wheel actuating device 22 side having a different rotational direction is Synchronization on the right rear wheel drive shaft 76 side is started.

  Thereafter, the first actuator 56 is actuated by the control signal E1 of the ECU 30 so that the driving force connecting / disconnecting device 54 of the first switching device 24 can be connected, and the spline phases of the differential case shaft 50 and the ring gear shaft 52 coincide. At this time, the first switching device 24 is connected and the four-wheel drive mode is set.

  When switching from the four-wheel drive mode to the two-wheel drive mode, first, the second actuator 82 is actuated by the control signal E2 of the ECU 30 to disconnect the second switching device 26. Further, the first actuator 56 is operated by the control signal E1 of the ECU 30 to forcibly disconnect the driving force connecting / disconnecting device 54 of the first switching device 24, and the connection between the differential case shaft 50 and the side gear shaft 52 is released. Thus, the two-wheel drive mode is set.

  Next, the connecting / disconnecting operation of the driving force connecting / disconnecting device 54 in the first switching device 24 when the drive mode is switched will be described with reference to FIG. 6-11.

  FIG. 6 is an explanatory view showing a state in the two-wheel drive mode of the driving force connecting / disconnecting device 54 of FIG. 3 (cutting state of the first switching device 24), and FIG. 6 (A) shows the first cam member 102. FIG. 6B is a cross-sectional view of the driving force connecting / disconnecting device 54, and shows a DD cross-sectional direction in FIG. 6A. Is shown.

  6A, the first cam member 102 forms a cam surface with the top surface 102b, the slope 102c and the bottom surface 102d of the convex portion 102a, and the second cam member 104 has a top surface 104b of the convex portion 104a. One cam member 102 is in contact with the top surface 102b.

  In FIG. 6B, the second cam member 104 is biased in the direction of the first cam member 102 by a coil spring 106. Further, the brake mechanism 108 and the check mechanism 116 are inactive.

  In the two-wheel drive mode, the intermediate shaft 100 rotates together with the differential case 40 of the front wheel differential device 20, but the ring gear shaft 52 receives the driving force from the rear wheels 84 and 86 because the second switching device 26 is cut off. Since it is not transmitted, it stops and the second cam member 104 splined to the ring gear shaft 52 is also stopped.

  The first cam member 102 is configured such that the frictional force between the top surface 102 b of the coil spring 106 and the top surface 104 b of the second cam member 104 is greater than the frictional force of the sliding surface with the intermediate shaft 100. Therefore, even if the intermediate shaft 100 is rotating in the two-wheel drive mode, the stopped state is maintained together with the second cam member 104.

  When switching from the two-wheel drive mode to the four-wheel drive mode, first, the synchronization of the second switching device 26 is started, whereby the ring gear shaft 52 and the second cam member 104 splined to the ring gear shaft 52 rotate. In addition, the first cam member 102 also rotates with the second cam member 104 due to the frictional force between the top surface 102b and the top surface 104b by the coil spring 106.

  Thereafter, when the brake mechanism 108 is actuated by the first actuator 56 to brake the first cam member 102, the first cam member 102 and the second cam member 104 start relative rotation.

  FIG. 7 is an explanatory view showing a state when the driving force connecting / disconnecting device 54 of FIG. 3 is switched from the two-wheel drive mode to the four-wheel drive mode. As in FIG. 6, FIG. A part of the first cam member 102 and the second cam member 104 are developed on a plane to show an engaged state. FIG. 7B is a cross-sectional view of the driving force connecting / disconnecting device 54, and is shown in FIG. -D shows a cross-sectional direction.

  As shown in FIGS. 7A and 7B, the second cam member 104 is rotated at the rotational speed V1 due to the connection of the second switching device 26, but the first cam member 102 is the first actuator 56. Is braked by the brake mechanism 108 actuated by pressing the piston 114 in the F direction, and decelerates from the rotational speed V1 to the rotational speed V2.

  When the first cam member 102 and the second cam member 104 rotate relative to each other, the engagement between the top surface 102 b and the top surface 104 b is released, and the top surface 104 b of the second cam member 104 is moved by the bias of the coil spring 106. The first cam member 102 can move in a direction in contact with the bottom surface 102d.

  In this state, if the phases of the spline 100s of the intermediate shaft 100 and the inner peripheral spline 104s of the second cam member 104 coincide with each other, the second cam member 104 moves until the top surface 104b contacts the bottom surface 102a. The inner circumferential spline 104 s of the second cam member 104 is coupled to the spline 100 s of the intermediate shaft 100.

  Further, when the spline 100s and the inner peripheral spline 104s are not in phase, the second cam member 104 is located at the position where the end of the inner peripheral spline 104s abuts the end of the spline 100s. The process waits until the phase is matched by the relative rotation of the member 102 and the second cam member 104.

  FIG. 7 shows this waiting state. In FIG. 7B, the second cam member 104 is located at the position where the end of the inner peripheral spline 104s abuts the end of the spline 100s. The movement in the direction of the member 102 stops, and in FIG. 7A, the convex portion 104a of the second cam member 104 is not in contact with the first cam member 102.

  FIG. 8 is an explanatory view showing a state when the driving force connecting / disconnecting device 54 of FIG. 3 is switched from the two-wheel drive mode to the four-wheel drive mode. As in FIG. 7, FIG. Part of the first cam member 102 and the second cam member 104 are developed on a plane to show an engaged state. FIG. 8B is a cross-sectional view of the driving force connecting / disconnecting device 54, and FIG. -D shows a cross-sectional direction.

  From the state shown in FIG. 7, when the first cam member 102 and the second cam member 104 further rotate relative to each other and the phases of the spline 100 s of the intermediate shaft 100 and the inner peripheral side spline 104 s of the second cam member 104 match, The second cam member 104 can move in the E direction approaching the first cam member 102.

  8A and 8B, the second cam member 104 is in a state where the top surface 104b reaches the bottom surface 102d of the first cam member 102, and the end of the top surface 104b contacts the inclined surface 102c. In contact therewith, the inner peripheral spline 104 s of the second cam member 104 starts to be coupled to the spline 100 s of the intermediate shaft 100.

  In this state, driving force is transmitted from the intermediate shaft 100 to the ring gear shaft 52 via the second cam member 104, and the second cam member 104 rotates at the same rotational speed V3 (≈V1) as the intermediate shaft 100, Transition to the four-wheel drive mode.

  Thereafter, the first actuator 56 retracts the piston 114 in the R direction until the top surface 104b of the second cam member 104 contacts the bottom surface 102d of the first cam member 102, whereby the first cam by the brake mechanism 108 is recovered. The braking of the member 102 is released.

  FIG. 9 is an explanatory diagram showing a state of the driving force connecting / disconnecting device 54 of FIG. 3 in the four-wheel drive mode (connection state of the first switching device 24), and FIG. 9 (A) is similar to FIG. FIG. 9B is a cross-sectional view of the driving force connecting / disconnecting device 54, showing a state in which a part of the first cam member 102 and the second cam member 104 are developed on a plane, and FIG. The DD cross-sectional direction is shown.

  As shown in FIGS. 9A and 9B, when the top surface 104b of the second cam member 104 contacts the bottom surface 102d of the first cam member 102, the inner peripheral side spline 104s of the second cam member 104 is obtained. Is completely coupled to the spline 100s of the intermediate shaft 100, and the driving force connecting / disconnecting device 54 completes the connection.

  The first cam member 102 is configured such that the frictional force between the bottom surface 102 d urged by the coil spring 106 and the top surface 104 b of the second cam member 104 is larger than the frictional force of the sliding surface with the intermediate shaft 100. Therefore, in the four-wheel drive mode, the second cam member 104 and the intermediate shaft 100 always rotate at the same rotational speed V3.

  When the torque is not applied between the intermediate shaft 100 and the ring gear shaft 52 in the two-wheel drive state, the second cam member 104 maintains the coupling state by the bias of the coil spring 106, and in the four-wheel drive state, the intermediate shaft When torque is applied between the ring gear shaft 52 and the ring gear shaft 52, the frictional force generated in the inner peripheral spline 104s and the outer peripheral spline 104t is further applied to maintain the coupled state.

  In addition, the check mechanism 116 rotates the first cam member 102 together with the second cam member 104 at the rotation speed V3, so that the centrifugal force acting on the stopper pin 118 reduces the biasing force of the spring 120 as shown in FIG. In this state, the function of restricting the range of relative rotation between the first cam member 102 and the second cam member 104 is not used.

  When switching from the four-wheel drive mode to the two-wheel drive mode, first, the second switching device 26 is disconnected, and then the first cam member 102 is actuated to brake the first cam member 102 by operating the brake mechanism 108. 102 and the second cam member 104 are relatively rotated, that is, when viewed from the second cam member 104 side, the first cam member 102 starts to rotate in the opposite direction.

  FIG. 10 is an explanatory view showing a state when the driving force connecting / disconnecting device 54 of FIG. 3 is switched from the four-wheel drive mode to the two-wheel drive mode. As in FIG. 9, FIG. Part of the first cam member 102 and the second cam member 104 are developed on a plane to show an engaged state, and FIG. 10B is a cross-sectional view of the driving force connecting / disconnecting device 54, and FIG. -D shows a cross-sectional direction.

  When the second cam member 104 is switched from the four-wheel drive mode to the two-wheel drive mode, the second cam member 104 rotates at the same rotational speed V3 as the intermediate shaft 100 even if the second switching device 26 is disconnected. As shown in (B), when the piston 114 is pressed in the F direction by the first actuator 56 to actuate the brake mechanism 108 and brake the first cam member 102, the first cam member 102 rotates from the rotational speed V3. Decelerate to speed V4.

  When the first cam member 102 and the second cam member 104 rotate relative to each other, the inclined surface 102c of the first cam member 102 presses the end of the top surface 104b of the second cam member 104, and the second cam member 104 Then, it moves in the G direction away from the first cam member 102 against the frictional force generated in the inner peripheral side spline 104 s and the outer peripheral side spline 104 t and the biasing force of the coil spring 106.

  FIG. 11 is an explanatory diagram showing a state when the switching from the four-wheel drive mode to the two-wheel drive mode of the driving force connecting / disconnecting device 54 of FIG. 3 is completed. Like FIG. 10, FIG. Part of the first cam member 102 and the second cam member 104 are developed on a plane to show an engaged state. FIG. 11B is a cross-sectional view of the driving force connecting / disconnecting device 54, and FIG. DD cross-sectional direction is shown.

  As shown in FIG. 11A, when the first cam member 102 and the second cam member 104 further rotate relative to each other from the state shown in FIG. 10, the convex portion 104 a of the second cam member 104 moves to the first cam member 102. Riding on the convex portion 102a, the top surface 104b comes into contact with the top surface 102b.

  The first cam member 102 and the second cam member 104 try to further rotate relative to each other while the top surface 102b and the top surface 104b are in contact with each other. However, as shown in FIG. Since the stopper pin 118 protrudes at this point, the stopper pin 118 engages with a locking portion 104c formed below the convex portion 104a of the second cam member 104, and the relative rotation between the first cam member 102 and the second cam member 104 is effected. regulate.

  Thereafter, the first actuator 56 retracts the piston 114 in the R direction, thereby releasing the braking of the first cam member 102 by the brake mechanism 108 and the two-wheel drive mode is set. The release of the brake mechanism 108 may be performed after the second cam member 104 starts to move until the top surface 104b engages with the top surface 102b of the first cam member 102.

  In this way, the second cam member 104 is moved using the driving force transmitted from the engine 32 transmitted to the intermediate shaft 100 to connect the intermediate shaft 100 and the ring gear shaft 52 so that torque transmission between both shafts can be performed. By forcibly releasing without waiting for disappearance, the driving force can be connected and disconnected with a small power (first actuator 54) that operates the brake mechanism 108, so that the two-wheel drive mode and the four-wheel drive mode are switched. The driving force connecting / disconnecting device 56 can be reduced in size and cost.

  In the driving force connecting / disconnecting device 54 of this embodiment shown in FIGS. 2-4 and 6-11, the first cam member 102 and the brake mechanism 108 are arranged on the driving force input side (the differential case shaft 50 and the intermediate shaft 100). However, a configuration in which it is arranged on the output side (ring gear shaft 52) is also possible.

  FIG. 12 is an explanatory view showing a second embodiment of the driving force transmission device for a four-wheel drive vehicle in which the driving force connecting / disconnecting device according to the present invention is arranged, and is a case where it is applied to a four-wheel drive vehicle based on an FF vehicle. . This embodiment is different from the first embodiment shown in FIG. 1 in that the driving force connecting / disconnecting device of the present invention is provided not in the first switching device but in the second switching device, and the first switching device includes a synchronization mechanism and a meshing clutch mechanism. Since the configuration is substantially the same except that is provided, only the portions different from FIG. 1 will be described.

  In FIG. 12, the driving force transmission device 212 of the present embodiment is provided in a four-wheel drive vehicle 210 and includes a front wheel driving unit 214, a driving force transmission unit 216, and a rear wheel driving unit 218. The driving device 220 and the driving force transmission unit 216 are provided with a rotation-sensitive coupling 228, and the rear wheel driving unit 218 is provided with a rear wheel differential device 222. A first switching device 224 is provided between the front wheel differential device 220 and the driving force transmission unit 216, and a second switching device 226 is provided between the rear wheel differential device 222 and the right rear wheel 286.

  In this embodiment, a meshing clutch mechanism 280 having a synchronization mechanism 278 is used as the first switching device 224, and the driving force connecting / disconnecting device 254 according to the present invention is used as the second switching device 226, and the first actuator 256, By operating the second actuator 282, it is possible to switch between a disconnected state in the two-wheel drive mode and a connected state in the four-wheel drive mode.

  The first switching device 224 is substantially the same as the first switching device 24 of the first embodiment except that a synchronization mechanism 278 and a meshing clutch mechanism 280 are provided instead of the driving force connecting / disconnecting device 54. Further, the synchronization mechanism 278 and the meshing clutch mechanism 280 are the same as those shown in FIG.

  Further, the second switching device 226 is substantially the same as the second switching device 26 of the first embodiment except that the driving force connecting / disconnecting device 254 of the present invention is provided in place of the synchronization mechanism 78 and the meshing clutch mechanism 80. Since the driving force connecting / disconnecting device 254 is the same as that shown in FIG. 2-4, detailed description thereof is omitted.

  FIG. 13 is an explanatory view showing a third embodiment of the driving force transmission device for a four-wheel drive vehicle in which the driving force connecting / disconnecting device according to the present invention is arranged, and is a case where it is applied to a four-wheel drive vehicle based on an FR vehicle. . This embodiment is substantially the same as the second embodiment shown in FIG. 12 except that the four-wheel drive vehicle is changed from the FF base to the FR base. Omitted.

  In FIG. 13, the driving force transmission device 312 of this embodiment is provided in a four-wheel drive vehicle 310 and includes a front wheel driving unit 314, a driving force transmission unit 316, and a rear wheel driving unit 318, and the front wheel driving unit 314 has a front wheel differential. The driving device 320 and the driving force transmission unit 316 are provided with a rotation difference sensitive coupling 328, and the rear wheel driving unit 218 is provided with a rear wheel differential device 322. A first switching device 324 is provided between the rear wheel drive unit 318 and the driving force transmission unit 316, and a second switching device 326 is provided between the front wheel differential device 314 and the right front wheel 348.

  In the present embodiment, as in the second embodiment shown in FIG. 12, the mesh clutch mechanism 380 having the synchronization mechanism 378 as the first switching device 324 and the driving force connecting / disconnecting device 354 according to the present invention as the second switching device 326 are used. The first actuator 356 and the second actuator 382 can be operated to switch between the disconnected state in the two-wheel drive mode and the connected state in the four-wheel drive mode.

  The synchronization mechanism 378 and the meshing clutch mechanism 380 of the first switching device 324 are the same as the configuration of the first embodiment shown in FIG. 5, and the second switching device 326 is the first embodiment shown in FIG. 2-4. Since the configuration is the same as those in FIG.

  Further, even in an FR-based four-wheel drive vehicle as shown in FIG. 13, the driving force connecting / disconnecting device according to the present invention is used for the first switching device as in the first embodiment shown in FIG. It is also possible to use a synchronization mechanism and a meshing clutch mechanism in the two-switching device.

Although the description of the embodiment is finished as described above, the present invention is not limited to the above-described embodiment, includes appropriate modifications without impairing the object and advantages thereof, and is further limited by numerical values shown in the above-described embodiment. I do not receive it.

10, 210, 310: Four-wheel drive vehicles 12, 212, 312: Driving force transmission devices 14, 214, 314: Front wheel driving unit 16, 216, 316: Driving force transmission units 18, 218, 318: Rear wheel driving unit 20 220, 320: Front wheel differential devices 22, 222, 322: Rear wheel differential devices 24, 224, 324: First switching devices 26, 226, 326: Second switching devices 28, 228, 328: Rotation difference sensitive type Coupling 30: ECU
32: Engine 34: Transmission 36: Drive gear 38, 58, 70: Ring gear 40, 72: Differential case 42: Left front wheel drive shaft 44: Right front wheel drive shaft 46: Left front wheel 48, 348: Right front wheel 50: Differential case shaft 52: Ring gear shafts 54, 254, 354: Driving force connection / disconnection devices 56, 256, 356: First actuator 60: Output pinion 62: Universal joint 64: Propeller shaft 66: Universal joint 68: Drive pinion 74: Left rear wheel Drive shaft 76: right rear wheel drive shaft 78, 278, 378: synchronization mechanism 80, 280, 380: meshing clutch mechanism 82, 282, 382: second actuator 84: left rear wheel 86, 286: right rear wheel 88, 122 : Housing 90, 92: Tapered roller bearing 94: Double row angular bearing 96, 98: Ball bearing 10 : Intermediate shaft 102: first cam member 104: second cam member 106: coil spring (biasing member)
108: Brake mechanism 110: Drum 112: Friction plate 114: Piston 116: Check mechanism 118: Stopper pin 120: Spring 124, 126: Taper roller bearing 128: Shift fork 130: Shift rod 132: Pinion

Claims (3)

In the driving force connecting / disconnecting device that coaxially arranges and connects and releases the first shaft and the second shaft that input and output the driving force,
A first cam member rotatably supported on the first shaft;
A second cam member that rotates with the second shaft and is movable between a position to be disconnected from the first shaft by being driven by the first cam member;
An urging member that presses the second cam member in a direction to connect to the first shaft ;
A brake mechanism that brakes rotation of the first cam member and relatively rotates the first cam member and the second cam member;
A check mechanism that operates when the first cam member is rotating and restricts the range of the relative rotation;
A driving force connecting / disconnecting device characterized by comprising:
The driving force connecting / disconnecting device according to claim 1.
The first cam member is relatively stationary with the second cam member by the pressing of the biasing member when the second cam member is at a position where the second cam member is cut or connected to the first shaft .
Said second cam member,
When the brake mechanism is operated when in a position to be disconnected from the first shaft, the biasing member is pressed to move to a position to be connected to the first shaft,
When the brake mechanism is operated when in a position to be connected to the first shaft, it moves to a position to be disconnected from the first shaft against the pressing of the biasing member,
The check mechanism restricts the relative rotation and holds the second cam member at the cutting position when the second cam member moves from the position connecting to the first shaft to the cutting position. A driving force connecting / disconnecting device.
  The driving force connecting / disconnecting device according to claim 1, wherein the check mechanism is operated by a centrifugal force acting on the first cam member.

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