Abstract A linear actuator according to the present disclosure includes an axially reciprocable piston having means controlling the radial position of the piston. Means is provided for imparting fluid pressure to opposite sides of the piston causing the piston to move axially. The piston is threadably engaged to a drive means so that axial movement of the piston imparts rotation movement to the drive means. An axially moveable thrust rod is threadably assembled to the drive means so that rotation of the drive means imparts axial motion to the thrust rod. In one form of the device, the piston is threadably engaged to the thrust rod which in turn is restrained from rotational movement. The piston is also threadably engaged to a sleeve which rotates with the piston, the sleeve being threadably engaged to the thrust rod so that radial movement of the sleeve drives the thrust rod axially. In another form of the device the piston is keyed to a key slot in a cylindrical bore, the key slot being helically wound so that the advance of the thrust rod is dependent upon the algebraic sum of the advance of the threaded assembly and the advance of the helical key slot.
A fluid-operable linear actuator comprising housing means having a bore and an axis; a sleeve journaled to said housing means within said bore for rotational movement about said axis, said sleeve having an internally threaded portion; an internally threaded piston means disposed within said sleeve; means for coupling said piston means to said sleeve; thrust rod means threadably assembled to said sleeve and said piston means; means for controlling the radial position of said thrust rod means; and means in said housing for selectively applying fluid pressure to opposite sides of said piston means, whereby fluid pressure applied to one side of said piston means causes said piston means to rotate about said axis to rotate said sleeve thereby urging said thrust rod means in an axial direction.
Claim 2
Dependent Claim
128 words
A fluid-operable linear actuator comprising housing means having a bore and an axis; a sleeve journaled to said housing means within said bore for rotational movement about said axis, said sleeve having an internally threaded portion; an internally threaded piston means disposed within said sleeve; means for coupling said piston means to said sleeve; thrust rod means threadably assembled to said sleeve and said piston means; means for controlling the radial position of said thrust rod means; and means in said housing for selectively applying fluid pressure to opposite sides of said piston means, whereby fluid pressure applied to one side of said piston means causes said piston means to rotate about said axis to rotate said sleeve thereby urging said thrust rod means in an axial direction.
Claim 3
Dependent Claim
43 words
Apparatus according to claim 1 wherein said first means comprises a key engaged to a key slot, one of said key and key slots being carried by said piston and the other of said key and key slots being carried by said sleeve.