Hydraulic and pneumatic cylinder construction

A fluid actuator, including:

• a cylindrical housing defining a chamber including a first region adjacent an open end of the housing, and a second region adjacent an opposite end of the housing;
• wherein the first region, at least along a portion thereof near the open end, has a first diameter, and the second region of the chamber has a second diameter less than the first diameter;
• wherein the housing incorporates a transition region extending from the second region to said portion of the first region to provide a gradual transition from the second diameter to the first diameter;
• a first end closure member insertable in a first axial direction into the chamber through the open end, and shaped for a conforming and contiguous surface engagement with the housing along the first region and along the transition region to position the first end closure member at a first predetermined location with respect to the cylindrical housing;
• and
• a closure structure for closing the housing at said opposite end thereof;
• where and the closure structure includes an opening there through.

A process for assembling a fluid actuator, including:

• providing a cylinder having first and second opposite open ends, a first diameter over a majority of its length including said first end, a second diameter larger than the first diameter along an end region of the cylinder including the second end, and a transition region providing a gradual transition between the First diameter and the second diameter;
• securing an end cap containment feature proximate the first end of the cylinder;
• inserting a first end cap into the cylinder through the second end, and moving the first end cap in a first axial direction along the cylinder until it contacts the containment feature and substantially closes the first end upon reaching a first predetermined location;
• after so inserting the first end cap, inserting a piston into the cylinder through the second end, and moving the piston in said first axial direction to a location beyond said transition region;
• after so inserting the piston, inserting a second end cap into the cylinder through the second end to a second predetermined location to substantially close said second end;
• and
• extending the piston rod from the piston, through an opening provided through a selected one of the end caps, to a piston rod termination outside of the cylinder.

A fluid actuator, including:

• a cylindrical housing defining a chamber including a first region adjacent an open end of the housing, a second region adjacent an opposite end of the housing, and a medial region between the first and second regions;
• a closure structure for closing the housing at said opposite end thereof;
• a first end closure member insertable in a first axial direction into the chamber through the open end, and shaped for a conforming and contiguous surface engagement with the housing;
• and
• a closure member mounting device for releasably securing the first end closure member with respect to the housing at a first predetermined location along the first region, including a first opening formed into the first end closure member, at least one second opening formed through the housing along the first region and positioned for an alignment with the first opening when the first end closure member is at the first predetermined location, and a pin insertable through the first and second openings for maintaining said alignment.

An actuator enclosure for containing a reciprocating piston, including:

• a cylindrical housing defining a chamber including a first end region, a second end region opposite the first end region and including an open end of the housing, and a medial region between the first and second end regions;
• a first end closure member insertable in a first axial direction into the chamber through the open end, and shaped for a conforming and contiguous surface engagement with the housing at a first predetermined location along the first end region;
• a second end closure member insertable in the first axial direction into the chamber through the open end, and shaped for a conforming and contiguous surface engagement with the housing at a second predetermined location along the second end region;
• and
• a closure member containing structure non-removably fixed with respect to the housing and positioned to engage the first closure member substantially upon a complete insertion thereof to the first predetermined location, thereby to prevent further travel of the first closure member in the first axial direction;
• wherein the housing is adapted to accommodate a piston for reciprocation along the medial region of the chamber, and a selected one of the first and second closure members includes an opening adapted to slideably support a piston rod coupled to the piston.

A fluid actuator including:

• a cylindrical housing defining a chamber including a first end region, a second end region opposite the first end region and including an open end of the housing, and a medial region between the first and second end regions;
• a first end closure member insertable in a first axial direction into the chamber through the open end, and shaped for a conforming and contiguous surface engagement with the housing at a first predetermined location along the first end region;
• an annular flexible first seal surrounding the first end closure member and adapted to be compressed between the first end closure member and the housing when the first end closure member is at the first predetermined location;
• a piston insertable in the first axial direction into the chamber through the open end for reciprocation along the medial region;
• an annular flexible piston seal surrounding the piston and adapted to be compressed between the piston and the cylindrical housing when the piston is disposed in the medial region;
• a second end closure member insertable in the first axial direction into the chamber through the open end, and shaped for a conforming and contiguous surface engagement with the housing at a second predetermined location along the second end region;
• an annular flexible second seal surrounding the second end closure member and adapted to be compressed between the cylindrical housing and the second end closure member when the second end closure member is at the second predetermined location;
• and
• a first fluid passage formed through a selected one of the end closure members and open to the medial region between the selected end closure member and the piston.