Apparatus and method for ratchet actuator

A ratchet actuator comprising:

• a housing;
• a pulley in rotating communication with said housing, said pulley being adapted to draw a traction element;
• a locking clutch encapsulated by said housing and disposed to control rotation of said pulley;
• a drive gear in rotationally driving communication with said pulley and said clutch;
• a ratchet in driving communication with said drive gear;
• and
• a lever in driving communication with said ratchet and rotationally fixed to said housing.

A ratchet actuator comprising:

• a lever housing having a drive axis and a ratchet axis;
• a lever, being fixed to said lever housing at said drive axis;
• a ratchet comprising:
• a ratchet post, said ratchet post being coaxial with and fixed to said lever housing ratchet axis;
• a first pawl having a first end in rotating communication with said ratchet post and having a second end, said second end having teeth and a pin;
• at least one second pawl having a first end in rotating communication with said ratchet post and having a second end, said second end having teeth and a pin;
• a pawl spring biasing said first pawl second end towards said second pawl second end;
• a drive gear having teeth, said drive gear teeth being dimensioned to mesh with said first and second pawl teeth and said drive gear being disposed to engage said pawls;
• and
• a second housing having a high step and at least one low step;
• each of said steps being disposed to mediate said pawl spring biasing of each of said pawls towards the other of each of said pawls by sliding contact with said pins;
• such that when one of said first or second pawl pins is in contact with said at least one low step, the other of said pins remains in contact with said high step;
• said low step being dimensioned to mesh said teeth of said one of said pawl ends having said pin contacting said low step with said teeth of said drive gear;
• and
• said high step being dimensioned to keep said teeth of said other pawl ends having said pin contacting said high step disengaged from said drive gear teeth;
• a locking clutch;
• in driven communication with said drive gear;
• a pulley for anchoring a traction element, said pulley being rotationally anchored in said second housing and being rotationally mediated by said locking clutch;

A ratchet actuator comprising:

• a housing;
• a lever rotationally fixed to said housing;
• a ratchet being in driving engagement with said lever;
• a drive disk being in driven engagement with said ratchet, said drive disk having fingers projecting perpendicular to the plane of the disk;
• a hub having at least two bosses defining at least two spaces between said bosses, said hub having at least two edges forming one side of each of said spaces and said each of said edges being dimensioned with a first hub distance and a second hub distance from a center of said hub with said edge being graduated from said first distance to said second distance;
• a ring surrounding said hub, said ring having an inner surface, said inner surface being in sliding rotational communication with said bosses, and said inner surface defining another side of each of said spaces;
• at least two locking rollers, disposed in said spaces said locking rollers being narrower in diameter than a distance between said ring inner surface and said hub edge first distance and said rollers being wider in diameter than a distance between said ring inner surface and said hub edge second distance;
• and
• at least two springs disposed between said bosses and said locking rollers such that said springs bias said locking rollers from said first distance and toward said second distance;
• a pulley for anchoring a traction element.

A ratchet actuator comprising:

• a lever;
• a lever housing having a drive axis and a ratchet axis;
• a ratchet comprising:
• a ratchet post, said ratchet post being coaxial with and fixed to said lever housing ratchet axis;
• a first pawl having a first end in rotating communication with said ratchet post and having a second end, said second end having teeth and a pin;
• at least one second pawl having a first end in rotating communication with said ratchet post and having a second end, said second end having teeth and a pin;
• a pawl spring biasing said first pawl second end towards said second pawl second end;
• a drive gear having teeth, said drive gear teeth being dimensioned to mesh with said first and second pawl teeth and said drive gear being disposed to engage said pawls;
• a second housing having a high step and at least one low step;
• each of said steps being disposed to mediate said pawl spring biasing of each of said pawls towards the other of each of said pawls by sliding contact with said pins;
• such that when one of said first or second pawl pins is in contact with said at least one low step, the other of said pins remains in contact with said high step;
• said low step being dimensioned to mesh said teeth of said one of said pawl ends having said pin contacting said low step with said teeth of said drive gear;
• and
• said high step being dimensioned to keep said teeth of said other pawl end having said pin contacting said high step disengaged from said drive gear teeth;
• a drive disk being engaged with said drive gear, said drive disk having fingers projecting perpendicular to the plane of the disk;
• a hub having at least two bosses defining at least two spaces between said bosses, said hub having at least two edges forming one side of each of said spaces and said each of said edges being dimensioned with a first hub distance and a second hub distance from
• a center of said hub with said edge being graduated from said first distance to said second distance;
• a ring surrounding said hub, said ring having an inner surface, said inner surface being in sliding rotational communication with said bosses, and said inner surface defining another side of each of said spaces;
• at least two locking rollers, disposed in said spaces said locking rollers being narrower in diameter than a distance between said ring inner surface and said hub edge first distance and said rollers being wider in diameter than a distance between said ring inner surface and said edge second distance;
• and
• at least two springs disposed between said bosses and said locking rollers such that said springs bias said locking rollers from said first distance and toward said second distance;
• a pulley for anchoring a traction element.

A ratchet actuated ergonomic device comprising:

• a housing;
• a pulley in rotating communication with said housing, said pulley being adapted to draw a traction element;
• a locking clutch encapsulated by said housing and disposed to control rotation of said pulley;
• a drive gear in rotationally driving communication with said pulley and said clutch;
• a ratchet in driving communication with said drive gear;
• a lever in driving communication with said ratchet and rotationally fixed to said housing;
• a traction cable having a first end and a second end, said first end being fixed to said pulley;
• and
• an ergonomic device being fixed to said traction cable second end and being actuatable by traction.

A method of actuating an ergonomic device comprising:

• rotating a pulley via a lever, ratchet and drive gear;
• controlling said rotating step by a clutch interaction step comprising:
• freewheeling of said rotation in a selected first rotational direction upon application of rotational force in said selected first direction;
• locking said pulley from rotating in a second rotational direction opposite said selected first direction upon removal of said rotational force in said first direction;
• selectively releasing said locking of said clutch upon application of rotational force in said second rotational direction;
• selectively applying rotational force in said first direction or said second direction with a lever and ratchet by moving a first of two pawls into driving engagement with said drive gear in said first rotational direction while disengaging a second of said two pawls from said drive gear and by moving a second of said two pawls into driving engagement with said drive gear in said second rotational direction while disengaging said first of said two pawls from said drive gear;
• returning said lever to a neutral position via a spring when rotational force is released;
• transferring said rotational force to tractive force via a cable end attached to said pulley;
• and
• actuating said ergonomic device via a second cable end attached to said ergonomic device.

A method of assembling an actuator comprising:

• enclosing in a housing a pulley and an overrunning clutch such that said clutch mediates driving said pulley in a first rotational direction, locking said pulley in a selected position when a force in said first rotational direction is released, and releasing said locking when a second force in an opposite rotational direction is applied;
• connecting said pulley and said overrunning clutch to a toothed drive gear via a shaft through said housing;
• engaging said toothed drive gear with a ratchet having two toothed pawls such that only one of said toothed pawls at a time meshes with said toothed drive gear;
• and
• maintaining said ratchet in said engagement via a lever having a fulcrum and a ratchet post, said ratchet post holding said pawls and said ratchet post being moveable along an arc, said arc being divided between a first section meshing a first of said two pawls with said drive gear in a direction corresponding to application of force in said first direction, and said arc having a second section meshing a second of said two pawls with said drive gear in a direction corresponding to said opposite direction.

A method of assembling an ergonomic device actuator comprising:

• enclosing in a housing a pulley and an overrunning clutch such that said clutch mediates driving said pulley in a first rotational direction, locking said pulley in a selected position when a force in said first rotational direction is released, and releasing said locking when a second force in an opposite rotational direction is applied;
• connecting said pulley and said overrunning clutch to a toothed drive gear via a shaft through said housing;
• engaging said toothed drive gear with a ratchet having two toothed pawls such that only one of said toothed pawls at a time meshes with said toothed drive gear;
• maintaining said ratchet in said engagement via a lever having a fulcrum and a ratchet post, said ratchet post holding said pawls and said ratchet post being moveable along an arc, said arc being divided between a first section meshing a first of said two pawls with said drive gear in a direction corresponding to application of force in said first direction, and said arc having a second section meshing a second of said two pawls with said drive gear in a direction corresponding to said opposite direction;
• attaching a first end of a traction element to said pulley;
• and
• attaching a second end of said traction element to said ergonomic device.