Fluid actuator construction

Claim 2

In a fluid actuator having a tubular body portion, a reciprocable piston within the body, an end plate at one end of the tubular body, an aperture through said end plate, a piston rod secured to said piston and extending through said aperture, a retaining plate against an outer face of said end plate, a bearing sleeve surrounding said piston rod adjacent said end plate and retained adjacent said end plate by said retaining plate, tie rods along said tubular body portion securing said end plate thereto, the improvement comprising aligned throughbores through said end plate and retaining plate through which said tie rods extend with a clearance fit, a recess at each throughbore at the interface between said retaining face and outer face of said end plate, external threads on said tie rods along portions extending within said recesses and along portions beyond said retaining plate, nuts threaded on said tie rods and located in said recess acting against said end plate to secure said end plate against the tubular body, and additional nuts threaded on said tie rods, located beyond said retaining plate, and acting against the retaining plate to secure it against said end plate, whereby said retaining plate and bearing sleeve can be removed without disassociating said end plate from the tubular body and the retaining plate and additional nuts aid the recessed nuts in holding said end plate against the tubular body.

Claim 3

In a fluid actuator having a tubular body portion, a reciprocable piston within the body, an end plate at one end of the tubular body, an aperture through said end plate, a piston rod secured to said piston and extending through said aperture, an externally removable cartridge at least partially received in said end plate, a central aperture through said cartridge through which said piston rod extends, tie rods along said tubular body portion secuRing said end plate thereto, and a retaining plate face-to-face against the end plate retaining the cartridge in the end plate, the improvement comprising throughbores in said end plate through which said tie rods extend in nonthreaded relationship with a clearance fit, throughbores in said retaining plate aligned with the throughbores in the end plate and through which said tie rods extend in nonthreaded relationship with a clearance fit, recesses in at least one of the facing surfaces of said end plate and retaining plate at the openings of the throughbores, external threads on portions of said tie rods including those portions located within said recesses and beyond the external surface of the retaining plate, said recesses being of sufficient depth to fully receive a nut between said plates and threaded on a tie rod, first nuts within the recesses on threaded portions of the tie rods and acting against the end plate, and second nuts on threaded portions of the tie rods beyond the retaining plate and acting against the retaining plate.

Claim 4

In a fluid actuator having a tubular body portion, a reciprocable piston within the body, an end plate at one end of the tubular body, an aperture through said end plate, a piston rod secured to said piston and extending through said aperture, an externally removable cartridge at least partially received in said end plate, a central aperture through said cartridge through which said piston rod extends, tie rods along said tubular body portion secuRing said end plate thereto, and a retaining plate face-to-face against the end plate retaining the cartridge in the end plate, the improvement comprising throughbores in said end plate through which said tie rods extend in nonthreaded relationship with a clearance fit, throughbores in said retaining plate aligned with the throughbores in the end plate and through which said tie rods extend in nonthreaded relationship with a clearance fit, recesses in at least one of the facing surfaces of said end plate and retaining plate at the openings of the throughbores, external threads on portions of said tie rods including those portions located within said recesses and beyond the external surface of the retaining plate, said recesses being of sufficient depth to fully receive a nut between said plates and threaded on a tie rod, first nuts within the recesses on threaded portions of the tie rods and acting against the end plate, and second nuts on threaded portions of the tie rods beyond the retaining plate and acting against the retaining plate.

Claim 5

In a fluid actuator having a tubular body, a reciprocable piston within the body, end plates at opposite ends of the tubular body, an aperture through one of said end plates, an externally removable cartridge at least partially received in a portion of said aperture, a piston rod secured to said piston and extending through said cartridge, tie rods securing said end plates together and against opposite ends of the tubular body and a retaining plate held against said one of said end plates to retain the cartridge in said aperture, the improvement comprising a plurality of nonthreaded throughbores in said one end plate for receiving the tie rods, said throughbores being counterbored at the surface against which the retaining plate is held, a plurality of nonthreaded throughbores in said retaining plate aligned with the throughbores of said one end plate, said tie rods extending through the aligned throughbores of said one end plate and said retaining plate, external threads on said tie rods at least along portions of each tie rod within said counterbores and beyond said retaining plate, a first nut on a threaded portion of each tie rod within each said counterbore and seated against said one end plate to tension the associated tie rod, and a second nut on a threaded portion of each said tie rod that extends beyond the retaining plate securing said retaining plate to said one end plate.

Claim 6

In a fluid actuator having a tubular body, a reciprocable piston within the body, end plates at opposite ends of the tubular body, an aperture through one of said end plates, an externally removable cartridge at least partially received in a portion of said aperture, a piston rod secured to said piston and extending through said cartridge, tie rods securing said end plates together and against opposite ends of the tubular body and a retaining plate held against said one of said end plates to retain the cartridge in said aperture, the improvement comprising a plurality of nonthreaded throughbores in said one end plate for receiving the tie rods, said throughbores being counterbored at the surface against which the retaining plate is held, a plurality of nonthreaded throughbores in said retaining plate aligned with the throughbores of said one end plate, said tie rods extending through the aligned throughbores of said one end plate and said retaining plate, external threads on said tie rods at least along portions of each tie rod within said counterbores and beyond said retaining plate, a first nut on a threaded portion of each tie rod within each said counterbore and seated against said one end plate to tension the associated tie rod, and a second nut on a threaded portion of each said tie rod that extends beyond the retaining plate securing said retaining plate to said one end plate.