Pressure cylinder with low tolerance fit capable of supporting large transverse loads

A pressure cylinder comprising a housing including a rear wall and defining a blind bore having a central axis and extending forwardly from the rear wall and opening at a front end of the housing;

• and a piston having a cross-sectional configuration corresponding to the cross-sectional configuration of the cylinder bore and mounted for axial sliding movement in the cylinder bore along said axis in response to introduction of pressurized fluid between the retracted position and an extended position in which a front end of the piston extends beyond a front end of the cylinder bore, characterized in that the cylinder bore has a constant diameter throughout its length, the piston defines a hollow, the pressurized fluid is introduced into the hollow of the piston, the housing is configured such that there are no points on the housing along said axis forwardly of the piston, the piston has a constant diameter throughout its length corresponding to the diameter of the cylinder bore, the piston defines a sliding and contiguous interface with the cylinder bore over substantially the entire peripheral surface of the piston, the area between the rear wall of the piston and the rear wall of the cylinder housing is maintained at atmospheric pressure at all times, and the contiguous interface between the piston and the cylinder bore is devoid of fluid seals.

A pressure cylinder comprising a housing defining a blind bore opening in the front end of the housing and a piston having a cross-sectional configuration corresponding to the cross-sectional configuration of the bore and mounted for sliding movement in the bore in response to an introduction of pressurized fluid between a retracted position and an extended position in which a front end of the piston extends beyond the front end of the bore, characterized in that the piston defines a bore, the pressurized fluid is introduced into the piston bore through a core member extending through the rear end of the cylinder and into the cylinder bore to dispose the forward end of the core within the piston bore, and the core member is mounted in the rear end the cylinder with a loose fit so as to allow the forward end of the core member to move radially to align itself squarely with the piston bore irrespective of manufacturing tolerances.

A pressure cylinder comprising a housing having an annular side wall defining a bore and a piston having a cross-sectional configuration corresponding to a cross-sectional configuration of the bore and mounted for sliding movement in the bore in response to an introduction of pressurized fluid, characterized in that the piston defines a hollow, the pressurized fluid is introduced into the hollow of the piston, and a switch is positioned in an opening in the side wall of the housing for coaction with switch means on the piston.

A pressure cylinder comprising a housing defining a bore and a piston having a cross-sectional configuration corresponding to a cross-sectional configuration of the bore and mounted for sliding movement in the bore in response to an introduction of pressurized fluid, characterized in that the piston defines a hollow, the pressurized fluid is introduced into the hollow of the piston, a slot is provided in the housing opening in the bore and exteriorally of the housing, and a work positioning member is positioned in the slot and secured to the piston so as to move in the slot in response to sliding movement of the piston in the bore.

A pressure cylinder comprising a housing defining a bore and a piston having a cross-sectional configuration corresponding to a cross-sectional configuration of the bore and mounted for sliding movement in the bore in response to an introduction of pressurized fluid, characterized in that the piston defines a hollow, the pressurized fluid is introduced into the hollow of the piston, a slot is provided in the housing which opens in the bore and exteriorally of the housing, and a work positioning member is positioned in the slot and secured to the piston so as to move in the slot in response to sliding movement of the piston in the bore.

A pressure cylinder comprising a housing defining a blind bore opening in a front end of the housing and a piston having an outer peripheral side wall having a cross-sectional configuration corresponding to the cross-sectional configuration of the bore and mounted for axial sliding movement in the bore in response to an introduction of pressurized fluid between a retracted position and an extended position in which a front end of the piston extends beyond the front end of the bore, characterized in that the piston defines a hollow, the pressurized fluid is introduced into the hollow of the piston, a cavity is provided in the housing opening in the bore, a switch is positioned in the housing cavity in confronting relation to the outer peripheral side wall of the piston, and means on the outer peripheral side wall of the piston coact with the switch to provide an indication of the axial position of the piston in the bore.

A pressure cylinder comprising a housing defining a circular bore and a piston having an outer peripheral side wall having a circular cross-sectional configuration corresponding to a cross-sectional configuration of the bore and mounted for axial sliding movement in the bore in response to an introduction of pressurized fluid, characterized in that the piston defines a hollow, the pressurized fluid is introduced into the hollow of the piston, an area between a rear wall of the piston and a rear wall of the cylinder housing is maintained at atmospheric pressure at all times an axially extending groove is provided in the outer peripheral surface of the piston, and a guide pin is mounted in the housing and includes an inner portion extending into the piston groove to guide in the groove and preclude rotation of the piston.