MARK A POPJOY
Engineers in Lansdale, PA

6698729, Mar 2, 2004

Jun 15, 2001

09/883050

Mark A. Popjoy - Lansdale PA 19446

F16F 902

267 6428, 267217, 267218, 188269

A gas spring for moving a load relative to a body includes a cylinder member having an axis, an inner surface forming a chamber, a rod end and a closed end, a piston rod seal/guide received in the rod end of the cylinder member, and a piston rod received in the seal/guide for movement into and out of the cylinder member. A floating piston is received in the cylinder member for movement along the axis and in sealed engagement with the inner wall to define in the chamber a gas section between the floating piston and the rod end and a closed end section between the floating piston and the closed end. A mass of gas under a pressure above atmospheric pressure is contained in the gas section. A powered drive is provided for moving the floating piston axially of the cylinder member to vary the volume of the gas section of the chamber. A sensing device senses a characteristic of the gas spring that is indicative of the force applied to the rod by the gas in the gas section and produces a signal indicative thereof. The signal generated by the sensing device is used to control the drive.

6047797, Apr 11, 2000

Mar 11, 1997

8/815423

Mark A. Popjoy - Lansdale PA

Fichtel & Sachs Industries, Inc. - Gastonia NC

F16F 906

188269

An adjustable installation includes a body and a member carried by the body for adjustment among a plurality of positions by movements substantially in tandem of two spaced-apart locations on the member. A controllable locking gas spring is coupled between the body and the member at one of the locations, and an emergency locking gas spring is coupled between the body and the member at the other of the locations. The emergency locking gas spring normally acts like a non-locking gas spring and is thus in a follower relationship to the controllable locking gas spring but is locked automatically in either of two ways, depending on its design. In some designs, the emergency locking gas spring locks when a force greater than a predetermined force is imposed on it. In other designs, the emergency locking gas spring is locked in response to a signal generated by an acceleration detector upon detection of an acceleration of the installation greater than a predetermined acceleration.

6145638, Nov 14, 2000

Dec 29, 1999

9/474228

Mark A. Popjoy - Lansdale PA

Fichtel & Sachs Industries, Inc. - Gastonia NC

F16F 934

18832213

An adjustable installation includes a body and a member carried by the body for adjustment among a plurality of positions by movements substantially in tandem of two spaced-apart locations on the member. A controllable locking gas spring is coupled between the body and the member at one of the locations, and an emergency locking gas spring is coupled between the body and the member at the other of the locations. The emergency locking gas spring normally acts like a non-locking gas spring and is thus in a follower relationship to the controllable locking gas spring but is locked automatically in either of two ways, depending on its design. In some designs, the emergency locking gas spring locks when a force greater than a predetermined force is imposed on it. In other designs, the emergency locking gas spring is locked in response to a signal generated by an acceleration detector upon detection of an acceleration of the installation greater than a predetermined acceleration.

6206153, Mar 27, 2001

Dec 29, 1999

9/474232

Mark A. Popjoy - Lansdale PA

Fichtel & Sachs Industries, Inc. - Gastonia NC

F16F9/32

188300

An adjustable installation includes a body and a member carried by the body for adjustment among a plurality of positions by movements substantially in tandem of two spaced-apart locations on the member. A controllable locking gas spring is coupled between the body and the member at one of the locations, and an emergency locking gas spring is coupled between the body and the member at the other of the locations. The emergency locking gas spring normally acts like a non-locking gas spring and is thus in a follower relationship to the controllable locking gas spring but is locked automatically in either of two ways, depending on its design. In some designs, the emergency locking gas spring locks when a force greater than a predetermined force is imposed on it. In other designs, the emergency locking gas spring is locked in response to a signal generated by an acceleration detector upon detection of an acceleration of the installation greater than a predetermined acceleration.

6092632, Jul 25, 2000

Oct 1, 1997

8/941912

Mark A. Popjoy - Lansdale PA
Robert Kopf - Sudbury MA

Fichtel and Sachs Industries, Inc. - Gastonia NC

F16F 952

188277

A gas spring has a single bypass across the piston that is controlled by a valve member of an elastomeric material, which restricts flow through the bypass when the gas spring is compressed (piston rod moving into the cylinder) and produces a pressure differential across the piston that varies inversely with temperature. The increasing force opposing compression of the gas spring due to the pressure differential across the bypass as the temperature of the gas spring, and thus the output force, decreases maintains the handle load more even over a range of temperatures. The elastomeric valve member has very little effect on the normal operation of the gas spring in the extension (rod moving out) mode.

8079310, Dec 20, 2011

Nov 25, 2009

12/625933

Mark Alexander Popjoy - Lansdale PA, US
Michael McGuinness - Warminster PA, US

LTK Consulting Services, Inc. - Ambler PA

B61F 1/14

105453, 1051991, 280 6159

A vertical position compensating device for a vehicle, a vehicle using the device, and a method for controlling the vertical position of a vehicle. The vehicle has a wheel set mounted on a chassis by a primary suspension system and a body mounted on the chassis through a secondary suspension system. The device is mounted on the body. As the vehicle is loaded or unloaded the device moves vertically with the body and also moves relative to the body in proportion to the deflection of the primary suspension system. The total motion of the device is used to adjust the vertical position of the body through the secondary suspension in a direction opposite to the deflection of the body to maintain the position of the body constant relative to a datum line.

5404972, Apr 11, 1995

Aug 17, 1994

8/291735

Mark A. Popjoy - Lansdale PA
Paul McDonnell - Warrington PA

Fichtel & Sachs Industries, Inc. - Colmar PA

F16F 952, F16F 500

188277

A gas spring comprises a first bypass with a one-way valve that allows fluid to bypass the piston when the piston moves outward and a second bypass with a temperature-compensating spring-biased one-way valve that allows fluid to bypass the piston when the piston is pushed inward with a force exceeding the total of the force due to the gas pressure of the gas spring and the force required to open the spring-biased valve. Variations due to temperature changes in the force required to retract the gas spring are minimized.

4989700, Feb 5, 1991

Dec 28, 1989

7/458306

Mark Popjoy - Lansdale PA

Fichtel & Sachs Industries, Inc. - Colmar PA

F16F 936

18832218

Rattling of the piston against the tube in a gas spring due to transient lateral loads on the piston are inhibited by engagement of the base of the piston ring groove with internal projections of a serrated inner edge of the sealing ring. Assurance against seizure of the sealing ring to the piston and preservation of a minimum width of the face seal between the sealing ring and the ringland to ensure against leakage are provided.