Automatic friction shoe
AssigneeCaldwell Manufacturing Company
InventorNorman R. Westfall
Life of this patent
Estimating the term…
Abstract
A sash platform for an automatic friction shoe connects to the shoe by means of a curved arm that fits into a correspondingly curved recess molded into the shoe body. An abutment limits the insertion of the curved arm into the shoe and holds a sash support blade at an operating level, and a curved holder surface supports the platform against the downward force of a sash. The shoe connects to a spring or counterbalance element and runs frictionally in a jamb liner channel.
Claims31
In a window sash friction shoe connectable to a counterbalance element for running vertically in a jamb liner channel to support a sash on a platform having a connector portion mounted within a recess of said shoe and a sash support portion extending from said shoe through a slot in said jamb liner channel, the improvement comprising:
- a. said connector portion of said platform having an arm curved around a point located on a sash side of said arm;
- b. said shoe having an arm holder surface bordering said recess for engaging a radially inside surface of said curved arm;
- and
- c. said shoe having an abutment surface engaging a side of said connector portion opposite to said arm holder surface.
In a sash friction shoe connected to a counterbalance element and having an offset sash platform creating a moment arm between the downward force on said platform of the weight of said sash and the upward force on said shoe of said counterbalance element, for torquing said shoe frictionally in a jamb liner channel in which said shoe runs, the improvement comprising:
- a. said platform having a connector with a curved arm insertable into a correspondingly curved recess of said shoe, for holding said platform on said shoe;
- b. the curvature of said connector arm and said recess being arranged so that downward force on said platform torquing said shoe frictionally in said jamb liner channel also urges said connector arm into said recess;
- and
- c. an abutment arranged on a lower region of said shoe for limiting downward movement of said platform.
A two-piece sash shoe having a resin body connected to a counterbalance element and slideable in a jamb liner channel and a sash platform connected to said body and extending from said body through a slot in said jamb liner channel to engage and support a lower corner of a sash, said sash shoe comprising:
- a. a sash support blade of said platform extending from a bottom region of said shoe, and a curved connector arm of said platform extending upward into a recess molded in said shoe;
- b. an abutment surface of said recess engaging said platform in a position limiting downward movement of said sash support blade;
- c. a holding surface of said recess engaging a radially inner surface of said curved connector arm of said platform to hold said platform in an operating position on said shoe;
- and
- d. said recess being formed with openings on a front side of said shoe facing said sash and on a rear side of said shoe opposite said sash.
Dependencies are inferred from the claim text.