Stepper actuator having a breaking mechanism

A stepper actuator comprising:

• a central gear selectively rotatable in clockwise and counter-clockwise directions;
• a first actuation member selectively moveable from a retracted position through a first actuation cycle, and operative to releasably engage and incrementally rotate the central gear through a prescribed angular displacement in the clockwise direction when moved through the first actuation cycle;
• a second actuation member selectively moveable from a retracted position through a second actuation cycle, and operative to releasably engage and incrementally rotate the central gear through a prescribed angular displacement in the counter-clockwise direction when moved through the second actuation cycle;
• and
• a braking mechanism coupled to the first and second actuation members, the braking mechanism being cooperatively engaged to and operative to prevent rotation of the central gear when the first and second actuation members are each in the retracted position, and disengaged from the central when one of the first and second actuation members is moved from the retracted position into a respective one of the first and second actuation cycles, the braking mechanism comprising:
• at least one elongate brake link pivotally connected to and extending between the first and second actuation members, the brake link being in a braking position when the first and second actuation members are each in the retracted position;
• a pair of brake struts which each define opposed fist and second end portions, the first end portion of each of the brake struts being pivotally connected to the brake link;
• and
• a locking collar pivotally connected to the second end portion of each of the brake struts, the locking collar being cooperatively engaged to and operative to prevent the rotation of the central gear when the brake link is in the braking position.

A stepper actuator comprising:

• a central gear selectively rotatable in clockwise and counter-clockwise directions;
• a first actuation member selectively moveable from a retracted position through a first actuation cycle, and operative to releasably engage and incrementally rotate the central gear through a prescribed angular displacement in the clockwise direction when moved through the first actuation cycle;
• a second actuation member selectively moveable from a retracted position through a second actuation cycle, and operative to releasably engage and incrementally rotate the central gear through a prescribed angular displacement in the counter-clockwise direction when moved through the second actuation cycle;
• a brake drum cooperatively engaged to the central gear so as to be concurrently rotatable therewith, the brake drum including a peripheral brake drum wall defining an inner contact surface;
• and
• a braking assembly including:
• an elongate brake link pivotally connected to and extending between the first and second actuation members;
• and
• a brake pad connected to the brake link and defining a braking surface which is selectively engageable with the inner contact surface of the brake drum wall, the brake pad being frictionally engaged to the brake drum to prevent rotation of the brake drum and the central gear when the first and second actuation members are each in the retracted position, and disengaged from the brake drum when one of the first and second actuation members is moved from the retracted position into a respective one of the first and second actuation cycles.

A stepper actuator comprising:

• a central gear selectively rotatable in clockwise and counter-clockwise directions;
• a first actuation member selectively moveable from a retracted position through a first actuation cycle, and operative to releasably engage and incrementally rotate the central gear through a prescribed angular displacement in the clockwise direction when moved through the first actuation cycle;
• a second actuation member selectively moveable from a retracted position through a second actuation cycle, and operative to releasably engage and incrementally rotate the central gear through a prescribed angular displacement in the counter-clockwise direction when moved through the second actuation cycle;
• and
• a braking mechanism coupled to the first and second actuation members, the braking mechanism being cooperatively engaged to and operative to prevent rotation of the central gear when the first and second actuation members are each in the retracted position, and disengaged from the central gear when one of the first and second actuation members is moved from the retracted position into a respective one of the first and second actuation cycles, the braking mechanism comprising:
• at least one elongate brake link pivotally connected to and extending between the first and second actuation members, the brake link being in a braking position when the first and second actuation members are each in the retracted position;
• and
• an elongate, flexible brake belt defining opposed first and second end portions which are connected to the brake link, the brake belt being cooperatively engaged to and operative to prevent the rotation of the central gear when the brake link is in the braking position.

A stepper actuator comprising:

• a central gear selectively rotatable in clockwise and counter-clockwise directions;
• a first actuation member selectively moveable from a retracted position through a first actuation cycle, and operative to releasably engage and incrementally rotate the central gear through a prescribed angular displacement in the clockwise direction when moved through the first actuation cycle;
• a second actuation member selectively moveable from a retracted position through a second actuation cycle, and operative to releasably engage and incrementally rotate the central gear through a prescribed angular displacement in the counter-clockwise direction when moved through the second actuation cycle;
• and
• a braking mechanism coupled to the first and second actuation members, the braking mechanism being cooperatively engaged to and operative to prevent rotation of the central gear when the first and second actuation members are each in the retracted position, and disengaged from the central gear when one of the first and second actuation members is moved from the retracted position into a respective one of the first and second actuation cycles, the braking mechanism comprising:
• at least one elongate brake link pivotally connected to and extending between the first and second actuation members, the brake link being in a braking position when the first and second actuation members are each in the retracted position;
• a brake housing disposed in close proximity to the brake link;
• and
• an elongate brake arm defining a proximal end portion which is pivotally connected to the brake housing and a distal end portion which is sized to be advanceable between any adjacent pair of gear teeth defined by the central gear;
• the brake link being cooperatively engageable to the brake arm in a manner wherein the distal end portion is disposed between an adjacent pair of the gear teeth when the brake link is in the braking position thus preventing rotation of the central gear, and the distal end portion of the brake arm is removed from between an adjacent pair of gear teeth when either of the first and second actuators is moved from the retracted position.

A stepper actuator comprising:

• a central gear selectively rotatable in clockwise and counter-clockwise directions;
• a first actuation member selectively moveable from a retracted position through a first actuation cycle, and operative to releasably engage and incrementally rotate the central gear through a prescribed angular displacement in the clockwise direction when moved through the first actuation cycle;
• a second actuation member selectively moveable from a retracted position through a second actuation cycle, and operative to releasably engage and incrementally rotate the central gear through a prescribed angular displacement in the counter-clockwise direction when moved through the second actuation cycle;
• and
• a braking mechanism coupled to the first and second actuation members, the braking mechanism being cooperatively engaged to and operative to prevent rotation of the central gear when the first and second actuation members are each in the retracted position, and disengaged from the central gear when one of the first and second actuation members is moved from the retracted position into a respective one of the first and second actuation cycles, the braking mechanism comprising:
• at least one elongate brake link pivotally connected to and extending between the first and second actuation members, the brake link being in a braking position when the first and second actuation members are each in the retracted position;
• a support block disposed in close proximity to the brake link;
• an actuation link pivotally connected to the support block;
• an adapter link pivotally connected to the actuation link;
• and
• an elongate brake bar pivotally connected to the adapter link;
• the brake link being cooperatively engaged to the brake bar in a manner wherein the brake bar is cooperatively engaged to and operative to prevent the rotation of the central gear when the brake link is in the braking position.