Mounting Clamp

Abstract

This mounting clamp is used as a truss adapter for support of fixtures, electrical and otherwise, from a truss ceiling. The clamp comprises a plate suspended by a pair of upstanding arms, each of which is formed by a bolt connected to an inverted U-shaped rectangular hanger member. The hangers and their associated bolts are inserted upwardly between the spaced beams of a bar joist from below and then the hangers are rotated 90 degrees before they are lowered into place to rest on both of the spaced beams, spreading the load, as the hanger arms are tightened to the plate. The plate carries a connector for mating to the object to be mounted. Leveling screws provide adjustment for orienting the mounted object. A vibration damping pad is included when appropriate. Variations of the clamp may be used in wall or parapet mount configurations.

1 . A mounting clamp for securing an object to a mounting surface of a structure, comprising: 
 (a) a rigid flat plate having a multiplicity of apertures to receive fasteners to accommodate attachment of said plate to said structure;    (b) a flange centrally located on a proximal surface of said plate for reception of said object, wherein said flange is flanked by two apertures of a first kind from the multiplicity of apertures, the apertures of a first kind being non-threaded and lying upon a longitudinal centerline of said plate; and    (c) two threaded fasteners of a first kind, each having a head broader than its body, engaging said plate at one of the apertures of a first kind with the head disposed at the proximal surface of said plate.    
   
   
       2 . The mounting clamp of  claim 1 , further comprising two brackets, wherein: 
 (a) each of said brackets comprises a rigid rectangular channel having a threaded aperture centrally located on a first longer side of the rectangular channel with an opposite longer side of the rectangular channel being open, and the threaded aperture being threadably compatible with the threaded fastener of a first kind; and    (b) each of said brackets is attached to and supported by an instance of the threaded fastener of a first kind in such manner that an end of the threaded fastener of a first kind, opposite the head, threadably engages said bracket with the open side of said bracket facing the distal surface of said plate.    
   
   
       3 . The mounting clamp of  claim 1 , further comprising, from the multiplicity of apertures, at least three apertures of a second kind disposed near the perimeter of said plate and threaded so as to cooperate in threadable engagement with threaded fasteners of a second kind for the purpose of using the threaded fasteners of a second kind to accomplish an adjustable offset between said plate and said mounting surface.  
   
   
       4 . The mounting clamp of  claim 3  comprising exactly four apertures of a second kind disposed one each near corners of said plate.  
   
   
       5 . The mounting clamp of  claim 1  further comprising a pad of resilient material disposed between said plate and said mounting surface.  
   
   
       6 . The mounting clamp of  claim 1  wherein the two threaded fasteners of a first kind are lag screws for threadable insertion into construction materials such as lumber, concrete or gypsum products.  
   
   
       7 . The mounting clamp of  claim 1  further comprising a pad of weatherproofing gasket material disposed between said plate and said mounting surface.  
   
   
       8 . A method of installing a mounting clamp to support an object from a joist of a building, 
 said joist including a pair of parallel beams having a space therebetween, each of said beams having substantially horizontal upper and lower surfaces; and    said mounting clamp comprising a pair of rigid brackets, a pair of bolts each having a head broader than its body, a rigid mounting plate having a multiplicity of apertures and a mounting flange, wherein:    said mounting flange is attached to said plate near the center of a proximal surface of said plate;    said pair of bolts respectively engage, from the multiplicity of apertures, a pair of apertures of a first kind lying on a longitudinal centerline of said plate flanking said mounting flange, said bolts entering said apertures from the proximal surface of said plate; and    each bracket from the pair of rigid brackets has a rectangular broad shallow inverted U-shape, and central to its broader side each said bracket is threadably engaged respectively by a corresponding one of said pair of bolts such that an open side of said bracket faces a distal surface of said plate;    wherein said method comprises the steps of:    aligning the broader sides of the pair of brackets to be parallel to the longitudinal centerline of said plate of said mounting clamp;    orienting said mounting clamp so that the pair of brackets can be pressed into said space at the lower surface of said joist;    pressing each of said bolts and said brackets into said space until said brackets are completely disposed above the upper surface of said joist;    rotating the head of each of said bolts so as to cause each of said brackets to rotate to a position transverse to said beams;    lowering said mounting clamp to allow said brackets to capture the upper surface of said beams; and    tightening said bolts into said brackets so as to draw said plate toward the lower surface of said beams securing said mounting clamp to said joist.    
   
   
       9 . The method of  claim 8  wherein, from the multiplicity of apertures, at least three apertures of a second kind are disposed one each near the corners of said plate and threaded for reception of adjustment screws to allow adjustment of said object to a desired orientation, said method further comprising the additional steps of: 
 threading, from a multiplicity of adjustment screws, one adjustment screw into each of the apertures of a second kind;    loosening said bolts sufficiently to allow said plate to be tilted to achieve the desired orientation of said object;    tightening each of the adjustment screws to make contact with the lower surface of said joist; and    making a final adjustment of said bolts and the adjustment screws to achieve the desired orientation of said object and to stabilize said mounting clamp to said joist.