Abstract A friction door holder having a door frame mounting bracket and a door supported channel formed with an elongated guide slot. The channel houses a self-lubricating friction assembly. A drive arm pivoted to the mounting bracket moves the friction assembly within the channel. The friction assembly comprises a slide block which has a generally U-shaped elongated body formed with generally parallel elongated depending sides positioned closely adjacent the sides of the channel and joined together by a base section located adjacent the guide slot. The slide block body includes firstly an elongated guide head projecting from the base and sandwiched between the edges of the guide slot, and secondly a plurality of projecting retainer legs depending from the corner extremities of the depending sides towards the channel bottom. A metal plate carrying a friction liner is housed within the slide block and is retained between the slide block legs; and an elongated cam spring is housed within the slide block with one end fixed to the slide block and the other end being free to move relative the slide block. An adjustment screw carried by the slide block contacts adjustably the free end of the cam spring to vary the degree of friction engagement between the friction liner and the channel. The slide block is preferably fabricated of a solid plastic, such as nylon, containing a homogeneously dispersed solid lubricant, such as molybdenum disulfide.
The combination of claim 1 in which the friction liner projects downwardly beyond the retainer legs to establish friction contact with the channel bottom with the retainer legs being the only portions of the slide block contacting the friction liner.
Claim 2
Dependent Claim
50 words
The combination of claim 2 in which the cam is part of an elongated spring fixed at one end to the base and guide head of the slide block and the other end being free to move relative the slide block in response to manual variations in the screw adjustment.
Claim 3
Dependent Claim
36 words
The combination of claim 3 in which the cam is a generally V-shaped crimp located substantially in the central portion of the elongated spring to apply a single substantially centrally located force on the friction liner.
Claim 4
Dependent Claim
238 words
In a friction door holder having a door frame mounting bracket, a door supported elongated, hollow channel formed with a pair of side walls, a bottom and a top having an elongated guide slot, with the channel housing a friction assembly, and a friction assembly drive arm coupling the mounting bracket and friction assembly to move the friction assembly relative the channel, the improved friction assembly comprising a slide block slidably movable within the channel, the slide block having a generally U-shaped elongated body formed with generally parallel elongated depending sides positioned closely adjacent the sides of the channel and joined together by a base section located adjacent the slot, with the body including firstly an elongated guide head projecting from the base and sandwiched between the edges of the guide slot and secondly a plurality of projecting retainer legs projecting from the corner extremities of the depending sides toward the channel bottom, a metal plate carrying a friction liner housed within the slide block between the slide block legs to be retained and guided thereby, an elongated cam spring housed within the slide block with one end fixed to the slide block and the other end being free to move relative the slide block, and an adjustment screw carried by the slide block to contact adjustably the free end of the cam spring to vary the degree of friction engagement between the friction liner and the channel.
Claim 5
Dependent Claim
22 words
The combination of claim 5 in which the slide block is fabricated of a solid plastic containing a homogeneously dispersed solid lubricant.
Claim 6
Dependent Claim
18 words
The combination of claim 6 in which the plastic is nylon and the solid lubricant is molybdenum disulfide.