Patents Assigned to P. L. Porter Company
  • Patent number: 5219045
    Abstract: Simplified assembly and reduced parts count in a linear mechanical lock assembly of the type where a rod is normally gripped against axial translation through a housing by a coil spring and released by unwinding the spring, is achieved by a one piece housing with integrally formed spring containment and rod bearing elements.
    Type: Grant
    Filed: October 19, 1992
    Date of Patent: June 15, 1993
    Assignee: P. L. Porter Company
    Inventors: Clyde R. Porter, George V. Babiciuc
  • Patent number: 5217195
    Abstract: A support mechanism for 6-way adjustable automotive seats has a base and a seat support mounted on the base by mechanical locks telescopable for adjusting the height and tilt of the seat support. The mechanism is improved in that spring biased levers compensate for variable spring force to apply an approximately constant seat lifting force throughout the adjustment range of the mechanism.
    Type: Grant
    Filed: February 16, 1989
    Date of Patent: June 8, 1993
    Assignee: P. L. Porter Company
    Inventors: Aki Tanaka, David E. Landis
  • Patent number: 5211379
    Abstract: A hydraulic positioner for seats includes a cylinder and piston structure with a piston rod secured to the piston and extending from the cylinder. A reservoir is provided in the cylinder by a gland jointly biased by a first spring located within the cylinder and a second spring which also urges the piston rod to an extended position. A sleeve is movable by the gland for visual indication of the hydraulic fluid in the cylinder.
    Type: Grant
    Filed: December 18, 1991
    Date of Patent: May 18, 1993
    Assignee: P. L. Porter Company
    Inventor: Clyde R. Porter
  • Patent number: 5157826
    Abstract: A mechanical lock where a rod axially translatable through a lock housing is normally gripped by a clutch spring axially fixed to the housing, and a lever is actuated for unwinding the spring to release the rod. The lock housing is formed in a single piece by die cutting and stamping from flat sheet stock in a sequence which can be carried out in a single progressive die, to minimize the parts count and simplify assembly of the lock.
    Type: Grant
    Filed: June 19, 1991
    Date of Patent: October 27, 1992
    Assignee: P. L. Porter Company
    Inventors: Clyde R. Porter, George V. Babiciuc
  • Patent number: 5150771
    Abstract: A mechanical lock of the type where as spring wound about a rod normally grips the rod against axial movement through a lock housing is improved by providing a lightly scored surface finish on contacting surfaces of the rod and the spring, the scoring being transverse to the rod and excluding contacting surfaces of adjacent coils of the spring for enhanced frictional resistance to axial sliding displacement of the rod through the spring while maintaining low friction unwinding of the spring.
    Type: Grant
    Filed: May 11, 1990
    Date of Patent: September 29, 1992
    Assignee: P. L. Porter Company
    Inventor: Clyde R. Porter
  • Patent number: 5133245
    Abstract: The stroke length in a positioner of the type having a piston rod movable through a cylinder can be preset through a continuous range of adjustment. A first detent element provided at the end of the cylinder engages another detent element positionable along the rod to limit stroke length. Spacing between the two detents is continuously adjustable by rotation of a threaded sleeve coaxial with the rod. Once installed in a recliner seat or the like, the device is secure against accidental changes in the stroke setting.
    Type: Grant
    Filed: April 12, 1991
    Date of Patent: July 28, 1992
    Assignee: P. L. Porter Company
    Inventors: Jimmy C. Lee, Calvin R. Stringer
  • Patent number: 5002172
    Abstract: An electrically driven lockable actuator for an airline seat assembly is provided with an extendable and retractable actuator arm driven through a gear train by an electric motor. The actuator arm can be locked or unlocked through the gear train to the electric motor by manual activation of a clutch mechanism. Regardless of whether the actuator arm is locked or unlocked, the position of the actuator arm is copied by a follower extending exterior to the actuator. The follower is adjustable to selectively activate limit switches to disconnect power to the driving motor. The switch arm is compact and mounted on the actuator so that electrical control of the motor relative to the operation of the lockable actuator is realized without reference to the nature of the design of the seat assembly.
    Type: Grant
    Filed: June 7, 1989
    Date of Patent: March 26, 1991
    Assignee: P. L. Porter Company
    Inventor: Calvin R. Stringer
  • Patent number: 4880084
    Abstract: A linear friction lock mechanism of the type having a rod axially translatable through a lock housing, at least one locking coil spring axially fixed to the housing and having an inner coil diameter such that the coil spring normally grips the rod against such axial movement, and a lock release mechanism actuatable for unwinding the locking coil spring thereby to free the rod for movement through the housing. This linear lock is improved by providing a backup latch element mounted to the housing and spring loaded towards interlocking engagement with the rod redundantly holds the rod against axial movement through the lock housing independently of the locking coil spring to eliminate creeping of the rod through the spring. Manual and remote cable release mechanisms are optional.
    Type: Grant
    Filed: July 5, 1988
    Date of Patent: November 14, 1989
    Assignee: P. L. Porter Company
    Inventors: Akira Tanaka, Jimmy C.-M. Lee
  • Patent number: 4759587
    Abstract: A power driven screw jack with manual override for adjusting the inclination of a pivotable backrest in a recliner seat has a housing attachable to the stationary portion of the seat and a screw attachable to the backrest. A nut threaded on the screw is normally fixed to the housing such that the screw may be motor driven to obtain axial displacement of the screw through the housing. A nut release is manually actuatable for freeing the nut from the housing, whereby the inclination of the backrest is adjustable by either turning the motor driven screw with the nut locked to the housing, or by linearly moving screw through the housing together with the nut released from the housing as by pushing on the backrest in case of power failure to the screw motor.
    Type: Grant
    Filed: August 27, 1987
    Date of Patent: July 26, 1988
    Assignee: P. L. Porter Company
    Inventor: David J. Bucka
  • Patent number: 4685736
    Abstract: An infinitely positionable backrest lock for a recliner seat has an upper plate hinged to a lower frame, and a gear train mounted to the lower frame and drivingly engaging the upper plate. The gear train includes a drum surface on which is wound a brake spring normally gripping the drum against rotation for locking the upper plate against pivotal movement. Positive locking of the drum and gear train is assured by an auxiliary spring and associated lever mechanism acting on the brake spring for increasing the frictional engagement between the brake spring and drum surface by more tightly winding the brake spring about the drum. Fail safe operation is assured by a bolt element spring loaded towards interlocking engagement with a toothed periphery of the drum wheel in the event of slippage between the drum surface and brake spring.
    Type: Grant
    Filed: April 30, 1986
    Date of Patent: August 11, 1987
    Assignee: P. L. Porter Company
    Inventors: Aki Tanaka, David E. Landis
  • Patent number: 4577730
    Abstract: An infinitely positionable mechanical lock having a housing and at least one bushing fixed to the housing, the bushing having an inclined spring abutment surface. A rod is axially slidable through the bushing relative to the housing. A coil spring is wound about the rod, the spring having a normal inner diameter smaller than the diameter of the rod such that the coil spring grips the rod against translational motion within the housing. The spring is prebiased against the inclined surface of the bushing into normal locking engagement with the rod absent an axial load on the rod relative to the housing. A release assembly is actuatable for partly unwinding the coil spring to thereby release the rod for movement relative to the housing.
    Type: Grant
    Filed: August 30, 1983
    Date of Patent: March 25, 1986
    Assignee: P. L. Porter Company
    Inventor: Clyde R. Porter
  • Patent number: 4480729
    Abstract: An anti-surge valve for installation in a cylindrical chamber permits a fluid to flow at low velocity into and out of a port that opens into the cylindrical chamber and is located on the concave wall of the cylindrical chamber, the valve preventing a high velocity flow of the fluid from the cylindrical chamber into the port. The valve includes a sealing tube that is positioned within the cylindrical chamber in juxtaposition with the port and coaxial with but spaced radially inward from the portions of the concave wall that surround the port. The sealing tube is maintained in this position by spacers surrounding the sealing tube and extending radially outwardly to the inner surface of the cylindrical chamber. The anti-surge valve is a unitary structure molded of rubber.
    Type: Grant
    Filed: October 3, 1979
    Date of Patent: November 6, 1984
    Assignee: P. L. Porter Company
    Inventor: Clyde R. Porter
  • Patent number: 4457406
    Abstract: A mechanical lock normally preventing axial motion of a rod with respect to a housing includes a coil spring which normally encircles and grips the rod tightly. The coil spring is mounted on the rod between a fixed bushing and a rotatable bushing. The two bushings are identical and interchangeable to reduce the cost and complexity of the device. The rotatable bushing is rotated by an actuating lever to unwind the spring so as to increase its diameter and thereby to release its grip on the rod. Both the fixed bushing and the rotatable bushing include beveled faces which permit the last few turns at both ends of the spring to become cocked on the rod to provide a true locking engagement with the rod. The last few turns of the spring adjacent the rotatable bushing are immediately released by a minimum of rotation of the bushing since it is not necessary for the unwinding of the spring to be transmitted through the entire length of the spring.
    Type: Grant
    Filed: May 28, 1981
    Date of Patent: July 3, 1984
    Assignee: P. L. Porter Company
    Inventor: Clyde R. Porter
  • Patent number: 4425987
    Abstract: A mechanical lock of the type in which axial translational movement of a rod is prevented by a coil spring which encircles the rod and grips it and being readily released by application of a relatively small force through a relatively short stroke, thereby permitting the mechanical lock to be controlled by a pushbutton control. Rotating bushings adjacent the ends of the springs have beveled faces which cause the locking turns at the ends of the spring to become cocked on the rod to provide a true locking action. The device is unlocked by rotation of the rotating bushings, which unwind the locking turns of the spring, thereby releasing the grip of the spring on the rod. The rotating bushings are rotated in opposite directions by actuating levers which extend outside of the housing of the device. The actuating levers are provided with rollers and are located at the same station along the axis of the rod.
    Type: Grant
    Filed: June 16, 1980
    Date of Patent: January 17, 1984
    Assignee: P. L. Porter Company
    Inventor: Clyde R. Porter
  • Patent number: 4155433
    Abstract: A stop member for limiting the range of adjustment provided by a positioning device. The positioning device is of the type wherein a piston is adjustable to various axial positions within a cylinder. The stop member has the form of a cup, coaxial with the cylinder and affixed to a portion of the piston rod which extends beyond the end of the cylinder, with the open end of the cup facing the cylinder. The diameter of the cup is sufficient to permit the end of the cylinder to advance into the cup as the piston is moved into the cylinder. The cylindrical wall of the cup is provided with axially-spaced slots. A stop element is inserted transversely to the axis through one of the slots and extends across the space within the cup to block the advancement of the cylinder into the cup, thereby limiting the relative movement of the cylinder with respect to the piston. In one embodiment, the stop element has a U-shape with its legs passing on opposite sides of the piston rod when the stop element is inserted.
    Type: Grant
    Filed: October 4, 1977
    Date of Patent: May 22, 1979
    Assignee: P. L. Porter Company
    Inventor: Clyde R. Porter
  • Patent number: 4099602
    Abstract: A hydraulic positioner for maintaining a given separation between its attachment points and having a bidirectional detenting action whereby the given separation can be altered only by application of a sufficiently large overriding force. A closed cylinder is divided into two closed fluid-filled chambers by a slidable piston. Motion of the piston requires transfer of fluid between the chambers. The transfer flow is determined by preloaded check valves in the transfer flow path. The check valves are preloaded in opposite directions to achieve the bidirectional detenting action. A reservoir supplies fluid under a small positive pressure to one of the closed fluid-filled chambers to replace fluid lost through leakage.
    Type: Grant
    Filed: August 31, 1977
    Date of Patent: July 11, 1978
    Assignee: P. L. Porter Company
    Inventor: John Kourbetsos