Actuator

Claim 2

An actuating device comprising: a ball-screw arrangement having a screw with external thread grooves and a nut with internal thread grooves engageable with said screw through ball bearings cooperatively received within said external and internal thread grooves, said nut being longitudinally movable along said screw on rotation of said screw relative thereto; support means on which said screw is mounted for rotation only; power means connected to said screw for rotation thereof to drive said nut longitudinally thereon from a first to a second position; a rotatable member mounted on said support means adapted for attachment to apparatus to be actuated; a mechanism connecting said nut and said rotating member adapted to convert longitudinal movement of said nut to rotary motion of said rotatable member; spring means mounted so as to bias said nut toward said first position; said power means being connected to said screw through clutch means, said clutch means being disengageable to allow rotation of said screw, said spring means being adapted to force said nut along said screw from said second position toward said first position when said clutch is disengaged.

Claim 3

An actuating device comprising: a ball-screw arrangement having a screw with external thread grooves and a nut with internal thread grooves engageable with said screw through ball bearings cooperatively received within said external and internal thread grooves, said nut being longitudinally movable along said screw on rotation of said screw relative thereto; support means on which said screw is mounted for rotation only; power means connected to said screw for rotation thereof to drive said nut longitudinally thereon from a first position to a second position; a rotatable member mounted on said support means adapted for attachment to apparatus to be actuated; a mechanism connecting said nut and said rotating member adapted to convert longitudinal movement of said nut to rotary motion of said rotatable member; spring means mounted so as to bias said nut toward said first position; said spring means comprises a cylindrical housing attached to said support means and a helical spring mounted in said housing, one end of said spring bearing against a pressure plate, said pressure plate being connected to said nut by shaft means so that on movement of said nut from said first position to said second position said pressure plate moves longitudinally within said housing to compress said spring.

Claim 4

An actuating device comprising: a ball-screw arrangement having a screw with external thread grooves and a nut with internal thread grooves engageable with said screw through ball bearings cooperatively received within said external and internal thread grooves, said nut being longitudinally movable along said screw on rotation of said screw relative thereto; support means on which said screw is mounted for rotation only; power means connected to said screw for rotation thereof to drive said nut longitudinally thereon from a first position to a second position; a rotatable member mounted on said support means adapted for attachment to apparatus to be actuated; a mechanism connecting said nut and said rotating member adapted to convert longitudinal movement of said nut to rotary motion of said rotatable member; spring means mounted so as to bias said nut toward said first position; said spring means comprises a cylindrical housing attached to said support means and a helical spring mounted in said housing, one end of said spring bearing against a pressure plate, said pressure plate being connected to said nut by shaft means so that on movement of said nut from said first position to said second position said pressure plate moves longitudinally within said housing to compress said spring.

Claim 5

An actuating device as set forth in claim 2, characterized by a pair of rods fixedly and longitudinally mounted within said housing, said pressure plate having a pair of holes through which said rods pass in sliding engagement.

Claim 6

An actuating device as set forth in claim 2 characterized in that said shaft means comprises a hollow tube surrounding a portion of said screw and longitudinally movable thereon with said nut.

Claim 7

An actuating device comprising: body means, a ball-screw mechanism having a screw mounted longitudinally within said body for rotation only and a nut engageable with said screw through ball bearing means and longitudinally movable along said screw on rotation of said screw; yoke means mounted in said body means for rotation on an axis substantially perpendicular to said screw and adapted for attachment to apparatus to be actuated; a mechanism coNnecting said nut and said yoke adapted to convert longitudinal movement of said nut to rotary movement of said yoke; power means connected to said screw for rotation thereof to cause said nut to move longitudinally therealong from a first position to a second position; spring means mounted on said body adapted to bias said nut toward said first position, said power means being connected to said screw by clutch means, said clutch means being disengageable when said nut is in said second position to allow said spring means to return said nut toward said first position.

Claim 8

An actuating device comprising: body means, a ball-screw mechanism having a screw mounted longitudinally within said body for rotation only and a nut engageable with said screw through ball bearing means and longitudinally movable along said screw on rotation of said screw; yoke means mounted in said body means for rotation on an axis substantially perpendicular to said screw and adapted for attachment to apparatus to be actuated; a mechanism coNnecting said nut and said yoke adapted to convert longitudinal movement of said nut to rotary movement of said yoke; power means connected to said screw for rotation thereof to cause said nut to move longitudinally therealong from a first position to a second position; spring means mounted on said body adapted to bias said nut toward said first position, said power means being connected to said screw by clutch means, said clutch means being disengageable when said nut is in said second position to allow said spring means to return said nut toward said first position.

Claim 9

An actuating device as set forth in claim 5, characterized in that said power means comprises an electric motor and said clutch means comprises sleeve means, mounted on the end of said screw for limited longitudinal movement, and a solenoid, said sleeve means being connected to said solenoid by a pivoting link, said solenoid being adapted, when energized, to pivot said link and move said sleeve means longitudinally into engagement with a portion of said clutch connected to said electric motor.

Claim 10

An actuating device as set forth in claim 5, characterized in that said spring means comprises a spring mounted in an elongated housing attached to said body, said spring bearing against a pressure plate which is connected to said nut by a tube surrounding said screw, said tube and said pressure plate being longitudinally movable on movement of said nut from said first position to said second position to compress said spring, said spring being expandable on disengagement of said clutch means to drive said nut longitudinally along said screw to said first position.

Claim 11

An actuating device as set forth in claim 7, characterized in that a pair of guide rods are mounted longitudinally within said housing, said pressure plate being provided with holes therein through which said rods pass in sliding engagement therewith.

Claim 12

A valve actuator comprising: a body affixed to a valve; a ball-screw mechanism comprising a screw mounted within said body for rotation only and a nut engageable with said screw through ball bearing means and longitudinally movable along said screw on rotation of said screw; yoke means rotatably mounted in said body and adapted for attachment to the stem of said valve; a mechanism connecting said nut and said yoke adapted to convert longitudinal movement of said nut to rotational movement of said valve stem; an electric motor connected to said screw through disengageable clutch means for rotation of said screw to drive said nut longitudinally therealong from a first position to a second position.

Claim 13

A valve actuator comprising: a body affixed to a valve; a ball-screw mechanism comprising a screw mounted within said body for rotation only and a nut engageable with said screw through ball bearing means and longitudinally movable along said screw on rotation of said screw; yoke means rotatably mounted in said body and adapted for attachment to the stem of said valve; a mechanism connecting said nut and said yoke adapted to convert longitudinal movement of said nut to rotational movement of said valve stem; an electric motor connected to said screw through disengageable clutch means for rotation of said screw to drive said nut longitudinally therealong from a first position to a second position.

Claim 14

A valve actuator as set forth in claim 9, characterized by a spring return assembly attached to said body having a spring exerting a force biasing said nut in a direction toward said first position whereby on disengagement of said clutch said nut is driven along said screw from said second position toward said first position.

Claim 15

A valve actuator as set forth in claim 10, characterized in that said spring is compressed between one end of an elongated housing and a pressure plate, said pressure plate being connected to said nut by a tube surrounding a portion of said screw.

Claim 16

A valve actuator as set forth in claim 11, characterized in that said spring return assembly is provided with guide means in engagement with said pressure plate preventing rotation thereof but permitting longitudinal movement of said plate within said housing.

Claim 17

An actuating device comprising: a housing portion capable of being affixed to a device to be actuated, a threaded first member mounted within said housing for rotation only, and a threaded second member engageable with said first member and movable therealong on rotation of said first member; a yoke device rotatably mounted in said housing and adapted to be attached to said device to be actuated; mechanism connecting said second member with said yoke device adapted to translate longitudinal movement of said second member into rotational movemeNt of said yoke device; motor means connected to said first threaded member through disengageable clutch means for rotation of said first member and thereby causing said yoke device to rotate; and further including a spring device tending to bias said yoke device toward a first position.

Claim 18

An actuating device comprising: a housing portion capable of being affixed to a device to be actuated, a threaded first member mounted within said housing for rotation only, and a threaded second member engageable with said first member and movable therealong on rotation of said first member; a yoke device rotatably mounted in said housing and adapted to be attached to said device to be actuated; mechanism connecting said second member with said yoke device adapted to translate longitudinal movement of said second member into rotational movemeNt of said yoke device; motor means connected to said first threaded member through disengageable clutch means for rotation of said first member and thereby causing said yoke device to rotate; and further including a spring device tending to bias said yoke device toward a first position.

Claim 19

The device of claim 13 and including combination means to cause connection and disconnection of said motor means through said clutch means, said clutch means including a pair of interlocking jaws with teeth of such configuration as to permit rotation of said first member by said motor means in only one direction.

Claim 20

The device of claim 14 wherein on said combination means being activated, and said motor means deactivated, the force exerted by said spring device is insufficient to cause rotation of said first member.

Claim 21

The device of claim 14, wherein said combination means, on activation, causes movement of one of said clutch jaws into interlocking connection with other jaw, and, on deactivation of such combination means, causes said one jaw to move out of such engagement.

Claim 22

The device of claim 16 wherein said combination means includes a solenoid.