Reciprocating linear fluid motor

A linear reciprocating motor comprising:

• a housing including a longitudinal cavity defined in part by a transverse wall;
• an elongated member including an upper end, and a piston portion having a pressure surface which, when the motor is operating, is spaced longitudinally from said transverse wall and in fluid communication therewith, said upper end and said piston portion being confined in the longitudinal cavity;
• drive means exerting a force on said upper end tending to forcibly move the elongated member endwise through the longitudinal cavity and said pressure surface toward said transverse wall;
• said drive means including an expansible fluid chamber formed by one end of the longitudinal cavity adjacent to the upper end of the elongated member, and spring means in pressure communication with the fluid chamber, said spring means being compressed when pressure is applied to an incompressible hydraulic fluid in the fluid chamber;
• hydraulic means for driving the elongated member endwise through the longitudinal cavity toward the fluid chamber in opposition to the force of the drive means;
• said hydraulic means including regulating means for regulating flow of a hydraulic fluid to and away from the pressure surface, said regulating means including control valve means movable between a first position in which the hydraulic fluid is admitted to the pressure surface for moving said upper end against the drive means and compressing the spring means, and a second position in which the hydraulic fluid is exhausted from the pressure surface, resulting in the elongated member being forcibly moved by the drive means endwise through the longitudinal cavity with the pressure surface moving toward the transverse wall;
• and
• limit means for diverting the force of the drive means away from the elongated member before the pressure surface reaches the transverse wall, so that the pressure surface is not driven hard against the transverse wall by the drive means and the elongated member free travels before coming to a stop and reversing its direction of movement;
• said limit means comprising a fluid outlet, and passageway means which, when open, communicates the fluid chamber with the fluid outlet and which closes in response to movement of the elongated member in opposition to the force of the drive means and opens in response to movement of said member in the direction of said force.

A linear reciprocating motor comprising:

• a housing including a longitudinal cavity defined in part by a transverse wall, a fluid inlet, a guide cavity spaced from the longitudinal cavity, and at least one pressure passageway communicating with the fluid inlet;
• an elongated member including an upper end, a galley portion, a land portion adjacent to said galley portion, and a piston portion having a pressure surface which, when the motor is operating, is spaced longitudinally from said transverse wall and in fluid communication therewith, said upper end and said piston portion being confined in the longitudinal cavity;
• drive means exerting a force on said upper end tending to forcibly move the elongated member endwise through the longitudinal cavity and said pressure surface toward said transverse wall;
• said drive means including an expansible fluid chamber formed by one end of the longitudinal cavity adjacent to the upper end of the elongated member, and spring means in pressure communication with the fluid chamber, said spring means being compressed when pressure is applied to an incompressible hydraulic fluid in the fluid chamber;
• hydraulic means for driving the elongated member endwise through the longitudinal cavity toward the fluid chamber in opposition to the force of the drive means;
• said hydraulic means including regulating means for regulating flow of a hydraulic fluid to and away from the pressure surface;
• said regulating means including control valve means movable between a first position in which the hydraulic fluid is admitted to the pressure surface for moving said upper end against the drive means and compressing the spring means, and a second position in which the hydraulic fluid is exhausted from the pressure surface, resulting in the elongated member being forcibly moved by the drive means endwise through the longitudinal cavity with the pressure surface moving toward the transverse wall;
• said control valve means reciprocating linearly and having a first end surface which is in pressure communication with the fluid inlet and receives an endwise force from inflowing hydraulic fluid tending to move the control valve means into its first position;
• said control valve means comprising a valve spool which reciprocates linearly in the guide cavity, and said first end surface of the control valve means comprising a first end surface of the valve spool;
• said regulating means including conduit means for delivering hydraulic fluid pressure to the control valve means to move the control valve means into its second position and hold it there until the pressure surface has moved a predetermined distance toward the transverse wall;
• and said conduit means including a transmitting galley defined by said galley portion and the longitudinal cavity and in pressure communication with the fluid inlet, and a first sidewall passageway with a first end directed toward the valve spool and a second end ported on the longitudinal cavity, said second end being closed when said land portion is adjacent to and in sliding contact with it and open when said land portion moves past it as the upper end of the elongated member moves against the drive means bringing said second end into communication with the transmitting galley and resulting in the delivery of hydraulic fluid pressure from the fluid inlet to the valve spool;
• at least one pin having a pressure end which is closely received in the pressure passageway, and a contact end which makes contact with said first end surface of the valve spool;
• and
• limit means for diverting the force of the drive means away from the elongated member before the pressure surface reaches the transverse wall, so that the pressure surface is not driven hard against the transverse wall by the drive means and the elongated member free travels before coming to a stop and reversing its direction of movement;
• said limit means comprising a fluid outlet, and passageway means which, when open, communicates the fluid chamber with the fluid outlet and which closes in response to movement of the elongated member in opposition to the force of the drive means and opens in response to movement of said member in the direction of said force.

A linear reciprocating motor comprising:

• a housing including a longitudinal cavity defined in part by a transverse wall;
• an elongated member including an upper end, and a piston portion having a pressure surface which, when the motor is operating, is spaced longitudinally from said transverse wall and in fluid communication therewith, said upper end and said piston portion being confined in the longitudinal cavity;
• drive means exerting a force on said upper end tending to forcibly move the elongated member endwise through the longitudinal cavity and said pressure surface toward said transverse wall;
• said drive means including an expansible fluid chamber formed by one end of the longitudinal cavity adjacent to the upper end of the elongated member, and PG,44 spring means in pressure communication with the fluid chamber, said spring means being compressed when pressure is applied to an incompressible hydraulic fluid in the fluid chamber;
• hydraulic means for driving the elongated member endwise through the longitudinal cavity toward the fluid chamber in opposition to the force of the drive means;
• said hydraulic means including regulating means for regulating flow of a hydraulic fluid to and away from the pressure surface, said regulating means including control valve means movable between a first position in which the hydraulic fluid is admitted to the pressure surface for moving said upper end against the drive means and compressing the spring means, and a second position in which the hydraulic fluid is exhausted from the pressure surface, resulting in the elongated member being forcibly moved by the drive means endwise through the longitudinal cavity with the pressure surface moving toward the transverse wall;
• limit means for diverting the force of the drive means away from the elongated member before the pressure surface reaches the transverse wall, so that the pressure surface is not driven hard against the transverse wall by the drive means and the elongated member free travels before coming to a stop and reversing its direction of movement;
• said limit means comprising a fluid outlet, and passageway means which, when open, communicates the fluid chamber with the fluid outlet and which closes in response to movement of the elongated member in opposition to the force of the drive means and opens in response to movement of said member in the direction of said force;
• an exhaust manifold in open communication with the fluid outlet;
• and
• a check valve positioned between the fluid chamber and the exhaust manifold, which check valve opens in response to a lowering of hydraulic fluid pressure in the fluid chamber below the level of hydraulic fluid pressure in the exhaust manifold to admit hydraulic fluid into the fluid chamber, and is closed when the pressure in the fluid chamber is equal to or greater than the pressure in the exhaust manifold.

A linear reciprocating motor comprising:

• a housing including a longitudinal cavity defined in part by a transverse wall, and a fluid inlet;
• an elongated member including an upper end, a galley portion, a land portion adjacent to said galley portion, and a piston portion having a pressure surface which, when the motor is operating, is spaced longitudinally from said transverse wall and in fluid communication therewith, said upper end and said piston portion being confined in the longitudinal cavity;
• drive means exerting a force on said upper end tending to forcibly move the elongated member endwise through the longitudinal cavity and said pressure surface toward said transverse wall;
• said drive means including an expansible fluid chamber formed by one end of the longitudinal cavity adjacent to the upper end of the elongated member, and spring means in pressure communication with the fluid chamber, said spring means being compressed when pressure is applied to an incompressible hydraulic fluid in the fluid chamber;
• hydraulic means for driving the elongated member endwise through the longitudinal cavity toward the fluid chamber in opposition to the force of the drive means;
• said hydraulic means including regulating means for regulating flow of a hydraulic fluid to and away from the pressure surface;
• said regulating means including control valve means movable between a first position in which the hydraulic fluid is admitted to the pressure surface for moving said upper end against the drive means and compressing the spring means, and a second position in which the hydraulic fluid is exhausted from the pressure surface, resulting in the elongated member being forcibly moved by the drive means endwise through the longitudinal cavity with the pressure surface moving toward the transverse wall;
• said control valve means reciprocating linearly and having a first end surface which is in pressure communication with the fluid inlet and receives an endwise force from inflowing hydraulic fluid tending to move the control valve means into its first position;
• said regulating means including conduit means for delivering hydraulic fluid pressure to the control valve means to move the control valve means into its second position and hold it there until the pressure surface has moved a predetermined distance toward the transverse wall;
• and said conduit means including a transmitting galley defined by said galley portion and the longitudinal cavity and in pressure communication with the fluid inlet, and a first sidewall passageway with a first end directed toward the control valve means and a second end ported on the longitudinal cavity, said second end being closed when said land portion is adjacent to and in sliding contact with it and open when said land portion moves past it as the upper end of the elongated member moves against the drive means bringing said second end into communication with the transmitting galley and resulting in the delivery of hydraulic fluid pressure from the fluid inlet to the control valve means;
• and
• limit means for diverting the force of the drive means away from the elongated member before the pressure surface reaches the transverse wall, so that the pressure surface is not driven hard against the transverse wall by the drive means and the elongated member free travels before coming to a stop and reversing its direction of movement;
• said limit means comprising a fluid outlet, and passageway means which, when open, communicates the fluid chamber with the fluid outlet and which closes in response to movement of the elongated member in opposition to the force of the drive means and opens in response to movement of said member in the direction of said force.

A spring powered impact tool comprising:

• a housing including a longitudinal cavity;
• a hammer that reciprocates linearly in the longitudinal cavity and has an upper end;
• a linear impact member in line with the hammer;
• drive means in line with the hammer for driving the hammer through a power stroke, which drive means exerts a force on said upper end tending to drive the hammer endwise through the longitudinal cavity into impacting contact with the impact member;
• said drive means including an expansible fluid chamber formed by one end of the longitudinal cavity adjacent to the upper end of the hammer, and spring means in pressure communication with the fluid chamber, said spring means being compressed when pressure is applied to an incompressible hydraulic fluid in the fluid chamber;
• a hammer return hydraulic system for moving the hammer endwise through the longitudinal cavity toward the fluid chamber in opposition to the force of the drive means;
• said hydraulic system including regulating means for alternately delivering hydraulic fluid pressure against the hammer for moving said upper end against the drive means and compressing the spring means, and exhausting hydraulic fluid pressure from the hammer to allow the drive means to forcibly move the hammer endwise through the longitudinal cavity into impacting contact with the impact member;
• and
• limit means for diverting the force of the drive means away from the hammer before the hammer reaches the end of its power stroke so that the hammer free travels before coming to a stop and reversing its direction of movement;
• said limit means comprising a fluid outlet, and passageway means which, when open, communicates the fluid chamber with the fluid outlet and which closes in response to movement of the hammer in opposition to the force of the drive means and opens in response to movement of the hammer in the direction of said force.