Patents by Inventor Patrick Y. Williams

Patrick Y. Williams has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 4770275
    Abstract: A leveller for a ladder has a pair of sliding legs telescopically engagable in respective up-right tubes (which may constitute the stiles of the ladder or separate tubes to be fixed to the stile of a ladder), and a substantially uniform continuous flexible ligament such as a wire rope fixed to upper regions of the legs and extending between the tubes and engaging with a support guide means which is fixed relative to the ladder structure or relative to the other apparatus on which the levelling device is mounted. When loaded, the ladder transmits its load through the support guide means to tension the ligament but when the load is removed (for example by subsidence of the ground beneath one of the legs) tension is released from the ligament allowing it to slide over the support guide means to cause rapid readjustment of the relative vertical positions of the ladder to compensate for variations in ground level, whereby the ladder is maintained in its desired attitude.
    Type: Grant
    Filed: January 29, 1987
    Date of Patent: September 13, 1988
    Inventor: Patrick Y. Williams
  • Patent number: 4665584
    Abstract: A door closing device has an upright tube closed at the bottom and containing a damping liquid, a sinker weight being arranged in the tube and connected to a flexible cord which extends out of the top of the tube for connection to a door so that a door is automatically closed when released, the sinker weight falling under gravity to pull the door closed. The device includes a passage extending through the sinker weight with a valve seat formed at the lower end of the passage and co-operating with a buoyant self-seating valve member (preferably a plastic ball which is not captive relative to the weight) which controls liquid flow through the passage when the weight sinks. As the door is opened, the weight is pulled rapidly upwards and lifts off the buoyant valve member. Preferably, the valve member substantially seals the passage in the weight and there is a clearance around the weight for passage of the damping liquid during closing of the door.
    Type: Grant
    Filed: June 5, 1986
    Date of Patent: May 19, 1987
    Inventor: Patrick Y. Williams
  • Patent number: 4323133
    Abstract: A folding framework for a wheelchair has side frames interconnected by front and rear toggle braces each preferably formed from a pair of U-shaped arms of spring wire and a linkage extends between the hinges of the toggle braces. A securing arm is latchable with the linkage to hold the structure in an erected condition, the arrangement being such that the side frames are maintained parallel to one another. Direct drive motors may be mounted on wheels and to facilitate folding the hinges of the toggle brace may be offset relative to the fore and aft line of the vehicle so that when folded the side frames are offset relative to one another and the motors overlap. Preferably a diagonal brace extends below the folding framework to maintain parallel alignment of the side frames and a latching arm co-operates with the linkage between the toggle braces so that on lifting the latching arm, the linkage and the toggle braces are displaced in the closing direction.
    Type: Grant
    Filed: February 29, 1980
    Date of Patent: April 6, 1982
    Inventor: Patrick Y. Williams
  • Patent number: 4273350
    Abstract: A folding wheelchair has side frames connected by front, rear and bottom toggle braces which in the folded position permit the side frames to come together. Each toggle brace is preferably formed from a pair of U-shaped elements hingeably connected at the base of the U, the toggle braces co-operating with the framework such that folding is initiated by lifting upwardly of the bottom toggle brace. This is best achieved by a rigid rod linking the front and rear toggle braces and carrying abutment element for engaging with the bottom toggle brace so that folding of the front and rear toggle braces cannot occur until the bottom toggle brace is lifted. The wheelchair may have at least one toggle brace of U-shaped members with the base of each U divided transversely to provide for relative rotational motion between the portions of each U-shaped member. The wheelchair may also have a novel folding footrest.
    Type: Grant
    Filed: March 5, 1979
    Date of Patent: June 16, 1981
    Inventor: Patrick Y. Williams