Four-mode switchable ratcheting clutch

The present disclosure relates to a ratcheting clutch using same sets of pawls and resilient elements to switch among four operating modes.

Known ratcheting one-way clutches generally have a single engaging side, provide ratcheting (free-wheel) function in only one circumferential direction, and cannot provide full lock or full free-wheel functionality. Known one-way ratcheting clutches designed to provide ratcheting in two circumferential directions require separate ratcheting elements, for example different sets pawls and ancillary components, for each circumferential direction, increasing the size, weight, complexity, and cost of the clutch.

According to aspects illustrated herein, there is provided a switchable clutch, including: a housing defining a pocket; a race arranged to receive rotational torque; a pawl including a portion disposed in the pocket; a spring ring located radially outward of the race and rotatable by a first actuator to a first circumferential position with respect to the pawl; a ramp ring located radially outward of the race; and a first resilient element fixedly connected to the spring ring and in contact with the pawl. In a free-wheel mode of the switchable clutch: the race is rotatable, with respect to the housing, in a first circumferential direction and in a second circumferential direction, opposite the first circumferential direction; and the first resilient element urges the pawl radially outwardly out of contact with the race. In a first one-way mode of the switchable clutch: the spring ring is in the first circumferential position with respect to the pawl; the first resilient element urges the pawl into contact with the race; and the pawl blocks rotation of the race, with respect to the housing, only in the first circumferential direction. In a locked mode of the switchable clutch, the ramp ring, the pawl, and the race are non-rotatably connected.

According to aspects illustrated herein, there is provided a switchable clutch, including: a housing; a race arranged to receive rotational torque and at least a portion of which is enclosed by the housing; a pawl; a spring ring located radially outward of the race; a ramp ring located radially outward of the race; and a first resilient element fixedly connected to the spring ring and in contact with the pawl. In a free-wheel mode of the switchable clutch: the race is rotatable, with respect to the housing, in a first circumferential direction and in a second circumferential direction, opposite the first circumferential direction; and the pawl is free of contact with the race. In a first one-way mode of the switchable clutch, the race is rotatable, with respect to the housing, only in the second circumferential direction. To transition from the free-wheel mode to the first one-way mode, the spring ring is arranged to be rotated, by a first actuator, in the first circumferential direction, and the first resilient element is arranged to displace the pawl into contact with the race. In a locked mode of the switchable clutch, the race is non-rotatably connected to the pawl. To transition to the locked mode from the free-wheel mode or from the first one-way mode: the ramp ring is arranged to be rotated, by the first actuator, in the first circumferential direction or in the second circumferential direction, and the ramp ring is arranged non-rotatably connect the pawl and the race; or the ramp ring is arranged to be rotated, by a second actuator, in the first circumferential direction or in the second circumferential direction, and the ramp ring is arranged non-rotatably connect the pawl and the race.

According to aspects illustrated herein, there is provided a method of operating a switchable clutch including a housing defining a pocket, a race, a pawl including a portion disposed in the pocket, a spring ring located radially outward of the race, a ramp ring located radially outward of the race, and a first resilient element fixedly connected to the spring ring, the method including: urging, with the first resilient element, the pawl radially outwardly and out of contact with the race for a free-wheel mode of the switchable clutch; enabling rotation of the race, with respect to the housing, in a first circumferential direction and in a second circumferential direction, opposite the first circumferential direction; rotating the spring ring, with a first actuator and with respect to the housing, in the first circumferential direction; tipping, with the first resilient element, a first distal end of the pawl into contact with the race; blocking, with the pawl and for a first one-way mode of the switchable clutch, rotation of the race, with respect to the housing, only in the first circumferential direction; rotating the spring ring, with the first actuator and with respect to the housing, in the second circumferential direction; tipping, with the first resilient element, a second distal end of the pawl into contact with the race; blocking, with the pawl and for a second one-way mode of the switchable clutch, rotation of the race, with respect to the housing, only in the second circumferential direction; and to transition to a locked mode of the switchable clutch from the free-wheel mode, the first one-way mode, or the second one-way mode: rotating, with respect to the housing and with the first actuator or with a second actuator, the ramp ring in the first circumferential direction or in the second circumferential direction, displacing, with the ramp ring, the pawl radially inwardly, and non-rotatably connecting the housing, the pawl, and the race.

Various embodiments are disclosed, by way of example only, with reference to the accompanying schematic drawings in which corresponding reference symbols indicate corresponding parts, in which:

FIG. 1 is a front isometric view of a switchable ratcheting clutch in a free-wheel mode;

FIG. 2 is a front view of the switchable ratcheting clutch shown in FIG. 1 ;

FIG. 3 is a side view of the switchable ratcheting clutch shown in FIG. 1 in an unspecified mode;

FIG. 4 is a cross-sectional view generally along line 4 , 8 , 10 , 12 , 13 - 4 , 8 , 10 , 12 , 13 in FIG. 3 ;

FIG. 5 is a cross-sectional view generally along line 5 - 5 in FIG. 2 ;

FIG. 6 is a detail of area 6 in FIG. 4 ;

FIG. 7 is a front view of the switchable ratcheting clutch shown in FIG. 1 in a first one-way mode;

FIG. 8 is a cross-sectional view generally along line 4 , 8 , 10 , 12 , 13 - 4 , 8 , 10 , 12 , 13 in FIG. 3 , with the switchable ratcheting clutch in the first one-way mode;

FIG. 9 is a front view of the switchable ratcheting clutch shown in FIG. 1 in a first aspect of a locked mode;

FIG. 10 is a cross-sectional view generally along line 4 , 8 , 10 , 12 , 13 - 4 , 8 , 10 , 12 , 13 in FIG. 3 , with the switchable ratcheting clutch in the first aspect of the locked mode;

FIG. 11 is a front view of the switchable ratcheting clutch shown in FIG. 1 in a second one-way mode;

FIG. 12 is a cross-sectional view generally along line 4 , 8 , 10 , 12 , 13 - 4 , 8 , 10 , 12 , 13 in FIG. 3 , with the switchable ratcheting clutch in the second one-way mode;

FIG. 13 is a cross-sectional view generally along line 4 , 8 , 10 , 12 , 13 - 4 , 8 , 10 , 12 , 13 in FIG. 3 , with the switchable ratcheting clutch in a second aspect of the locked mode; and,

FIG. 14 has two views 14 A and 14 B and is a schematic block diagram of the switchable clutch shown in FIG. 1 with two actuator configurations.

At the outset, it should be appreciated that like drawing numbers on different drawing views identify identical, or functionally similar, structural elements of the disclosure. It is to be understood that the disclosure as claimed is not limited to the disclosed aspects.

Furthermore, it is understood that this disclosure is not limited to the particular methodology, materials and modifications described and as such may, of course, vary. It is also understood that the terminology used herein is for the purpose of describing particular aspects only, and is not intended to limit the scope of the present disclosure.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood to one of ordinary skill in the art to which this disclosure belongs. It should be understood that any methods, devices or materials similar or equivalent to those described herein can be used in the practice or testing of the disclosure.

FIG. 1 is a front isometric view of switchable ratcheting clutch 100 in a free-wheel mode.

FIG. 2 is a front view of switchable ratcheting clutch 100 shown in FIG. 1 .

FIG. 3 is a side view of switchable ratcheting clutch 100 shown in FIG. 1 in an unspecified mode.

FIG. 4 is a cross-sectional view generally along line 4 , 8 , 10 , 12 , 13 - 4 , 8 , 10 , 12 , 13 in FIG. 3 .

FIG. 5 is a cross-sectional view generally along line 5 - 5 in FIG. 2 . The following should be viewed in light of FIGS. 1 through 5 . Switchable clutch 100 includes: housing 102 forming pockets 104 ; and race 106 . Race 106 : is arranged to receive one or both of rotational torque T 1 and T 2 in circumferential direction CD 1 and circumferential direction CD 2 , respectively; and is supported for rotation around axis of rotation AR. Circumferential directions CD 1 and CD 2 are with respect to a radius centered on axis AR and swept around axis AR. Line L 1 , described infra includes such a radius. Circumferential direction CD 2 is opposite circumferential direction CD 1 . Clutch 100 includes pawls 108 . Each pawl 108 includes: portion 110 disposed in a respective pocket 104 ; and portion 111 radially disposed between housing 102 and race 106 . Clutch 100 includes: spring ring 112 located radially outward of race 106 ; ramp ring 114 located radially outward of race 106 ; and resilient elements 116 fixedly connected to ring 112 . Each element 116 is in contact with a respective pawl 108 .

In an example embodiment, an entirety of race 106 is enclosed by housing 102 in radially outer direction RD 1 , orthogonal to axis AR. In an example embodiment, portion 117 of ring 112 is enclosed by housing 102 in direction RD 1 . In an example embodiment, an entirety of ring 114 is enclosed by housing 102 in radially outer direction RD 1 .

Ring 112 is rotatable with respect to housing 102 , pawls 108 , and ring 114 by actuator A. For example, ring 112 is rotatable in directions CD 1 and CD 2 with respect to housing 102 , pawls 108 , and ring 114 by actuator A. Ring 114 is rotatable with respect to housing 102 , pawls 108 , and ring 112 by actuator A. For example, ring 114 is rotatable in directions CD 1 and CD 2 with respect to housing 102 , pawls 108 , and ring 112 by actuator A. In an example embodiment, ring 112 and ring 114 are off-set and overlap in axial direction AD 1 , parallel to axis AR. Pawls 108 overlap rings 112 and ring 114 in radially outer direction RD 1 . In an example embodiment, clutch 100 includes actuator A.

In a free-wheel mode of switchable clutch 100 : resilient elements 116 urge at least portions, for example portions 111 , of the respective pawls 108 radially outwardly, in radially outer direction RD 1 , and out of contact with race 106 ; and race 106 is rotatable, with respect to housing 102 , in circumferential direction CD 1 and in circumferential direction CD 2 . In an example embodiment, in the free-wheel mode of switchable clutch 100 , resilient elements 116 urge respective entireties of the respective pawls 108 radially outwardly, in radially outer direction RD 1 , and out of contact with race 106 . In the free-wheel mode of switchable clutch 100 : ring 112 is in a first circumferential position with respect to housing 102 and pawls 108 ; and ring 114 is in a first circumferential position with respect to housing 102 and pawls 108 .

By “circumferential position” of one component to another, we mean a position of the component defined by directions CD 1 and CD 2 with respect to the other component. Stationary straight line L, orthogonal to axis AR, is used as a benchmark for the circumferential positions of ring 112 and ring 114 . By ‘stationary” we mean that: a rotational position of line L, with respect to axis AR, is fixed; or a circumferential position of line L, with respect to housing 102 , is fixed.

FIG. 6 is a detail of area 6 in FIG. 4 . The following should be viewed in light of FIGS. 1 through 6 . In an example embodiment, ring 112 includes brackets 118 , extending radially inwardly from annular portion 120 of ring 112 and in axial direction AD 2 with respect to portion 120 . In an example embodiment, annular portion 120 is unbroken, that is continuous, in directions CD 1 and CD 2 . Each pawl 108 : is partially enclosed by a respective bracket 118 , or overlaps a respective bracket 118 in direction RD 1 .

In an example embodiment, ring 114 includes: ramps 122 , sloping radially inwardly in direction CD 1 ; and ramps 124 sloping radially inwardly in direction CD 2 . Ramps 122 and 124 are grouped in pairs. In the example of FIG. 1 in the free-wheel mode, line L: passes through circumferential center point 126 of bracket 118 A to define the first circumferential position of ring 112 ; bisects pawl 108 A in directions CD 1 and CD 2 ; and is circumferentially centered between ramps 122 A and 124 A to define the first circumferential position of ring 114 . It is understood that the discussion for pawl 108 A, bracket 118 A, and ramps 122 A and 124 A is applicable to the remaining pawls 108 , brackets 118 , and ramps 122 and 124 of clutch 100 . In the discussion above and the discussion that follows, capital letters are used to designate a specific component from a group of components otherwise designated by a three digit number, for example, pawl 108 A is a specific pawl from among pawls 108 .

FIG. 7 is a front view of switchable clutch 100 shown in FIG. 1 in a first one-way mode.

FIG. 8 is a cross-sectional view generally along line 4 , 8 , 10 , 12 , 13 - 4 , 8 , 10 , 12 , 13 in FIG. 3 , with switchable clutch 100 in the first one-way mode. The following should be viewed in light of FIGS. 1 through 8 . In the first one-way mode: spring ring 112 is in a second circumferential position with respect to housing 102 and pawls 108 ; and, resilient elements 116 hold pawls 108 in contact with race 106 . In the first one-way mode, pawls 108 : block rotation of race 106 , with respect to housing 102 and pawls 108 , in direction CD 1 ; and enable rotation (ratcheting) of race 106 , with respect to housing 102 and pawls 108 , in direction CD 2 . In the second circumferential position of ring 112 , ring 112 , brackets 118 and center points 126 are shifted in direction CD 1 with respect to stationary line L 1 . In the first one-way mode, ring 114 remains in the first circumferential position of ring 114 .

In an example embodiment, each pawl 108 includes: protrusion 128 extending in circumferential direction CD 1 , and protrusion 130 extending in circumferential direction CD 2 . In an example embodiment, protrusion 128 and protrusion 130 form respective portions of each pawl 108 extending furthest in directions CD 1 and CD 2 , respectively. In the first one-way mode: protrusions 130 are in contact with race 106 ; protrusions 130 block rotation of race 106 , with respect to housing 102 , in circumferential direction CD 1 ; and for torque T 2 , protrusions 130 slide or ratchet along race 106 , enabling rotation of race 106 , with respect to housing 102 , in circumferential direction CD 2 .

FIG. 9 is a front view of switchable clutch 100 shown in FIG. 1 in a first aspect of a locked mode.

FIG. 10 is a cross-sectional view generally along line 4 , 8 , 10 , 12 , 13 - 4 , 8 , 10 , 12 , 13 in FIG. 3 , with switchable clutch 100 in the first aspect of the locked mode. The following should be viewed in light of FIGS. 1 through 10 . In the first aspect of the locked mode of switchable clutch 100 : pawls 108 are non-rotatably connected to race 106 to non-rotatably connect race 106 and housing 102 for torque T 1 and T 2 . In the first aspect of the locked mode: ring 112 is in the first circumferential position of ring 112 ; ring 114 is in a second circumferential position with respect to housing 102 and pawls 108 ; and ring 114 , in particular ramps 124 , is in contact with pawls 108 . Ring 114 and ramps 124 push at least respective portions, for example respective entireties, of pawls 108 radially inwardly, in radial direction RD 2 , into contact with race 106 , and against the urging of resilient elements 116 in direction RD 1 . For example, protrusions 128 and 130 are each pushed into non-rotatable contact with race 106 .

By “non-rotatably connected” components, we mean that components are connected so that whenever one of the components rotates, all the components rotate; and relative rotation between the components is precluded. Radial and/or axial movement of non-rotatably connected components with respect to each other is possible. Components connected by tabs, gears, teeth, or splines are considered as non-rotatably connected despite possible lash inherent in the connection. The input and output elements of a closed clutch are considered non-rotatably connected despite possible slip in the clutch. The input and output parts of a vibration damper, engaged/in contact with springs for the vibration damper, are not considered non-rotatably connected, due to the compression and unwinding of the springs.

FIG. 11 is a front view of switchable clutch 100 shown in FIG. 1 in a second one-way mode.

FIG. 12 is a cross-sectional view generally along line 4 , 8 , 10 , 12 , 13 - 4 , 8 , 10 , 12 , 13 in FIG. 3 , with switchable clutch 100 in the second one-way mode. The following should be viewed in light of FIGS. 1 through 12 . In the second one-way mode: spring ring 112 is in a third circumferential position with respect to housing 102 and pawls 108 ; and, resilient elements 116 hold pawls 108 in contact with race 106 . Pawls 108 : block rotation of race 106 , with respect to housing 102 and pawls 108 , in direction CD 2 ; and enable rotation, ratcheting, of race 106 , with respect to housing 102 and pawls 108 , in direction CD 1 . In the third circumferential position of ring 112 , center point 126 is shifted in direction CD 2 with respect to stationary line L 1 . In the second one-way mode, ring 114 remains in the first circumferential position of ring 114 .

For example, in the second one-way mode: protrusions 128 are in contact with race 106 ; protrusions 128 block rotation of race 106 , with respect to housing 102 , in circumferential direction CD 2 ; and for torque T 1 , protrusions 128 slide or ratchet along race 106 , enabling rotation of race 106 , with respect to housing 102 , in circumferential direction CD 1 .

In an example embodiment, clutch 100 includes resilient element 132 and resilient element 134 disposed in slot 136 defined by ring 114 . Radially outwardly extending protrusion 138 of housing 102 is circumferentially located between resilient element 132 and resilient element 134 in slot 136 . For the first circumferential position of ring 114 : element 132 reacts against fixed protrusion 138 to urge ring 114 in direction CD 2 ; element 134 reacts against fixed protrusion 138 to urge ring 114 in direction CD 1 ; and the respective spring forces from elements 132 and 134 equilibrate to hold ring 114 in the first circumferential position without the use of an actuator.

FIG. 13 is a cross-sectional view generally along line 4 , 8 , 10 , 12 , 13 - 4 , 8 , 10 , 12 , 13 in FIG. 3 , with switchable clutch 100 in a second aspect of the locked mode. The following should be viewed in light of FIGS. 1 through 13 . In the second aspect of the locked mode of switchable clutch 100 : pawls 108 are non-rotatably connected to race 106 to non-rotatably connect race 106 and housing 102 for torque T 1 and T 2 . In the second aspect of the locked mode: ring 112 is in the first circumferential position of ring 112 ; ring 114 is in a third circumferential position with respect to housing 102 and pawls 108 ; and ring 114 , in particular ramps 122 , is in contact with pawls 108 . The third circumferential position of ring 114 is shifted in direction CD 2 with respect to the first circumferential position of ring 114 . Ring 114 and ramps 122 push at least respective portions, for example respective entireties, of pawls 108 radially inwardly, in radial direction RD 2 , into contact with race 106 , and against the urging of resilient elements 116 in direction RD 1 . For example, protrusions 128 and 130 are each pushed into non-rotatable contact with race 106 .

The following provides further detail regarding example structure and operation of clutch 100 . Actuator A is used to rotate ring 112 and ring 114 among the various circumferential positions noted above. In the example of FIG. 1 , actuator A is an electric motor with an axially displaceable pinion gear PG. The following is directed to an example configuration of actuator A.

For the free-wheel, first one-way, and second one-way modes, a solenoid (not visible in the drawings) of actuator A is activated to displace gear PG in direction AD 1 to engage ring 112 . In the example of FIG. 1 , clutch 100 includes toothing 140 , fixedly connected to ring 112 , and extending radially outwardly from circumferentially continuous annular portion 120 of ring 112 . Actuator A displaces gear PG in direction AD 1 to mesh with toothing 140 . In an example embodiment (not shown), toothing 140 is integral to ring 112 .

To transition from the free-wheel mode to the first one-way mode, actuator A rotates gear PG in direction RTD 1 to rotate ring 112 in direction CD 1 . To transition from the free-wheel mode to the second one-way mode, actuator A rotates gear PG in direction RTD 2 to rotate ring 112 in direction CD 2 . To transition from the first one-way mode to the free-wheel mode or the second one-way mode, actuator A rotates gear PG in direction RTD 2 to rotate ring 112 in direction CD 2 . To transition from the second one-way mode to the free-wheel mode or the first one-way mode, actuator A rotates gear PG in direction RTD 1 to rotate ring 112 in direction CD 1 .

In the example of FIG. 1 , for the free-wheel, first one-way mode, and second one-way mode, actuator A is disengaged from ring 114 and resilient elements 132 and 134 hold ring 114 in the first circumferential position of ring 114 . Thus, ring 114 is free of contact with pawls 108 for the free-wheel, first one-way, and second one-way modes.

In an example embodiment, ring 114 includes teeth 144 . In the example of FIG. 1 , for the locked mode, the solenoid (not shown) of actuator A is de-energized so that gear PG retracts in direction AD 2 , opposite direction AD 1 , to disengage from ring 112 and mesh with teeth 144 of ring 114 . Prior to de-energizing the solenoid: actuator A displaces ring 112 to the first circumferential position (the free-wheel mode position) of ring 112 ; or extracting gear PG from ring 112 enables ring 112 to circumferentially displace, in response to the operation of ring 114 described below, to the first circumferential position of ring 112 .

To transition to the first aspect of the locked mode, with ring 114 in the first circumferential position, actuator A is arranged to pivot gear PG in direction RTD 1 to: displace ring 114 in direction CD 1 ; compress resilient element 132 against protrusion 138 ; and slide pawls 108 along radially inwardly sloping ramps 124 to displace at least respective portions of pawls 108 radially inwardly into non-rotatable contact with race 106 .

To transition to the second aspect of the locked mode, with ring 114 in the first circumferential position, actuator A is arranged to pivot gear PG in direction RTD 2 to: displace ring 114 in direction CD 2 ; compress resilient element 134 against protrusion 138 ; and slide pawls 108 along radially inwardly sloping ramps 122 to displace at least respective portions of pawls 108 radially inwardly into non-rotatable contact with race 106 .

Each resilient element 116 includes: distal end 146 in contact with distal end 128 of a respective pawl 108 ; and distal end 148 in contact with distal end 130 of a respective pawl 108 . Distal ends 146 and 148 urge protrusions 128 and 130 , respectively, radially outwardly with forces F 1 and F 2 , respectively. To transition from the locked mode, the free-wheel mode or the second one-way mode to the first one-way mode: actuator A is arranged to slide elements 116 along radially inwardly facing surfaces 150 of pawls 108 in direction CD 1 , increasing force F 1 , while decreasing force F 2 ; and ends 146 tip protrusions 130 into contact with race 106 . In an example embodiment, race 106 includes radially outwardly extending teeth 152 and teeth 152 define slots 154 . In the first one-way mode, protrusions 130 displace into respective slots 154 and contact respective walls 156 of teeth 152 to prevent rotation of race 106 , with respect to housing 102 , in direction CD 1 .

To transition from the locked mode, the free-wheel mode or the first one-way mode to the second one-way mode: actuator A is arranged to slide elements 116 along radially inwardly facing surfaces 150 of pawls 108 in direction CD 2 , increasing force F 2 , while decreasing force F 1 ; and ends 148 tip protrusions 128 into contact with race 106 . In the second one-way mode, protrusions 128 displace into respective slots 154 and contact respective walls 158 of teeth 152 to prevent rotation of race 106 , with respect to housing 102 , in direction CD 2 .

To transition to the locked mode from the free-wheel mode, the first one-way mode, or the second one-way mode, actuator A is arranged to slide elements 116 along radially inwardly facing surfaces 150 of pawls 108 in direction CD 1 or CD 2 to place ring 112 in the first circumferential position of ring 112 and substantially equalize force F 1 and force F 2 .

In the locked mode, for each pawl 108 : end 128 and end 130 are disposed in respective slots 154 ; and contact of end 128 and end 130 with wall 158 and 156 of the respective slots 154 prevents rotation of race 106 with respect to pawls 108 and housing 102 . In an example embodiment, clutch 100 includes plate 160 axially disposed between ring 112 and ring 114 and in contact with ring 112 and ring 114 .

FIG. 14 is a schematic block diagram of switchable clutch 100 with two actuator configurations. Unless stated otherwise, the structure and operation of clutch 100 depicted in FIG. 14 is the same as the structure and operation of clutch 100 depicted in FIGS. 1 through 13 . FIG. 14 depicts two example configurations of actuators. The first configuration uses actuator A as described in the discussion for FIGS. 1 through 13 . The second configuration uses separate actuators ACT 1 and ACT 2 to rotate ring 112 and ring 114 , respectively. Both configurations are shown in FIG. 14 with the understanding that the configurations are alternatives and are not meant to be implemented concurrently. Actuators ACT 1 and ACT 2 can be part of clutch 100 or can be separate from clutch 100 .

Actuator ACT 1 performs the operations on ring 112 described for actuator A in the discussion for FIGS. 1 through 13 . For example, actuator ACT 1 engages with ring 112 and rotates ring 112 among the respective circumferential positions of ring 112 associated with the locked mode, the free-wheel mode, the first one-way mode, and the second one-way mode of clutch 100 . Actuator ACT 2 performs the operations on ring 114 described for actuator A in the discussion for FIGS. 1 through 13 . For example, actuator ACT 2 rotates ring 114 among the respective circumferential positions of ring 114 associated with the locked mode, the free-wheel mode, the first one-way mode, and the second one-way mode of clutch 100 . In an example embodiment, actuators ACT 1 and ACT 2 engage structure similar to toothing 140 and teeth 144 , respectively.

For the example configuration with actuators ACT 1 and ACT 2 , actuators ACT 1 and ACT 2 can remain engaged with ring 112 and ring 114 , respectively, for all the operating modes of clutch 100 , since actuators ACT 1 and ACT 2 rotate ring 112 and ring 114 , respectively, independent of each other. Since actuators ACT 1 and ACT 2 rotate ring 112 and ring 114 , respectively, independent of each other, resilient elements 132 and 134 are not necessary to position ring 114 for the free-wheel mode, the first one-way mode, and the second one-way mode, and in an example embodiment, are not included in clutch 100 .

The following should be viewed in light of FIGS. 1 through 14 and describes a method of operating switchable clutch 100 . Although the method is presented as a sequence of steps for clarity, no order should be inferred from the sequence unless explicitly stated. A first step, urges, with a resilient element 116 , a pawl 108 radially outwardly and out of contact with race 106 for a free-wheel mode of switchable clutch 100 . A second step enables rotation of race 106 , with respect to housing 102 , in circumferential direction CD 1 and in circumferential direction CD 2 . A third step rotates spring ring 112 , with actuator A or actuator A 1 and with respect to housing 102 , in circumferential direction CD 1 . A fourth step tips, with resilient element 116 , distal end 130 of the pawl 108 into contact with race 106 . A fifth step, for a first one-way mode of switchable clutch 100 : blocks, with the pawl 108 , rotation of race 106 , with respect to housing 102 , only in circumferential direction CD 1 ; and enables rotation of race 106 , with respect to housing 102 , only in circumferential direction CD 2 .

A sixth step rotates spring ring 112 , with actuator A or actuator A 1 and with respect to housing 102 , in circumferential direction CD 2 . A seventh step tips, with the resilient element 116 , distal end 128 of the pawl 108 into contact with race 106 . An eighth step, for a second one-way mode of switchable clutch 100 : blocks, with the pawl 108 , rotation of race 106 , with respect to housing 102 , only in circumferential direction CD 2 ; and enables rotation of race 106 , with respect to housing 102 , only in circumferential direction CD 1 .

To transition to a locked mode of switchable clutch 100 from the free-wheel mode, the first one-way mode, or the second one-way mode, a ninth step: rotates, with respect to housing 102 and with actuator A or with actuator A 2 , ramp ring 114 in circumferential direction CD 1 or in circumferential direction CD 2 ; displaces, with ramp ring 114 , the pawl 108 radially inwardly against the urging of the resilient element 116 ; and non-rotatably connects housing 102 , the pawl 108 , and race 106 .

The ramp ring includes: ramp 122 sloping radially inwardly in direction CD 1 ; and ramp 124 sloping radially inwardly in direction CD 2 . In an example embodiment, rotating, with respect to housing 102 and with actuator A or with actuator A 2 , ramp ring 114 in circumferential direction CD 1 or in circumferential direction CD 2 includes sliding ramp 124 along the pawl 108 or sliding ramp 122 along the pawl 108 , respectively.

A tenth step, from the locked mode: urges, with resilient element 132 or resilient element 134 , ramp ring 114 out of contact with ramp 122 or with ramp 124 ; displaces, with actuator A or actuator A 1 and with respect to housing 102 , spring ring 112 ; and transitions to the free-wheel mode, the first one-way mode, or the second one-way mode.

Switchable ratcheting clutch 100 provides a four-mode clutch solution (the first one-way mode, the second one-way mode, the free-wheel mode, and the locked mode), using the same sets of pawls 108 and resilient elements 116 for each mode. Thus, the same pairs of pawls 108 and resilient elements 116 replace the known use of separate sets of components, for example sets of pawls and ancillary components, for each mode of a ratcheting clutch. As a result, clutch 100 reduces the parts count, complexity, weight, and production costs associated with dual one-way mode functionality. In addition, clutch 100 provides a free-wheel mode and a locked mode using the same sets of pawls 108 and resilient elements 116 .

It will be appreciated that various of the above-disclosed and other features and functions, or alternatives thereof, may be desirably combined into many other different systems or applications. Various presently unforeseen or unanticipated alternatives, modifications, variations, or improvements therein may be subsequently made by those skilled in the art which are also intended to be encompassed by the following claims.

A actuator

ACT 1 actuator

ACT 2 actuator

AD 1 axial direction

AD 2 axial direction

AR axis of rotation

CD 1 circumferential direction

CD 2 circumferential direction

F 1 force

F 2 force

L 1 line

PG pinion gear, actuator

RD 1 radially outer direction

RD 2 radially inner direction

RTD 1 rotational direction, pinion gear

RTD 2 rotational direction, pinion gear

100 switchable ratcheting clutch

102 housing

104 pocket

106 race

108 pawl

108 A pawl

110 portion, pawl

111 portion, pawl

112 ring

114 ring

116 resilient element

117 portion, ring 112

118 bracket, ring 112

118 A bracket, ring 112

120 annular portion, ring 112

122 ramp, ring 114

122 A ramp, ring 114

124 ramp, ring 114

124 A ramp, ring 114

126 center point bracket

128 distal end, pawl

130 distal end, pawl

132 resilient element

134 resilient element

136 slot, ring 114

138 protrusion, housing

140 toothing, ring 112

144 tooth, ring 114

146 distal end, element 116

148 distal end, element 116

150 radially inward surface, pawl 108

152 tooth, inner race

154 slot, inner race

156 wall, tooth 152

158 wall, tooth 152

160 plate