Mobile boom-mounted shop light

Claim 1

A mobile shop light comprising (a) A base having means to provide mobility; (b) A stand vertically attached to said base; (c) A boom assembly comprising an arm, a light fixture attached to one end of said arm and a counterweight attached to an opposite end of said arm; and (d) Attaching means connected to an upper end of said stand which attach said stand to said boom assembly, said attaching means allowing said boom assembly to rotate in a horizontal plane, to rotate in a vertical plane, and to be positioned firmly at various angles with respect to said stand, said attaching means comprising (i) A bearing sleeve nested within the upper end of said stand and rotatable with respect thereto, (ii) A U-bracket rigidly attached to said bearing sleeve and rotatably attached to said boom assembly, (iii) A transverse friction plate rigidly attached to said bearing sleeve in a horizontal plane, (iv) Transverse braking means rigidly attached to the upper end of said stand such that a braking action may be applied to said transverse friction plate allowing the relative rotation between said stand and said boom assembly to be arrested, (v) A vertical friction plate rigidly attached to said boom assembly, and (vi) Vertical braking means rigidly attached to said U-bracket such that a braking action may be applied to said vertical friction plate allowing the relative rotation between said U-bracket and said boom assembly to be arrested; (e) Said arm of said boom assembly further comprising an outer sleeve pivotally affixed to said U-bracket such that said outer sleeve is vertically rotatable with respect to said U-bracket, said outer sleeve being sized to receive a portion of an inner rod which is rotatable about a longitudinal axis of said outer sleeve and which extends outward of said outer sleeve, and said light fixture is pivotally attached to an outward end of said fixture is pivotally attached to an outward end of said inner rod; (f) Said mobile shop light further comprising a rotational friction plate rigidly attached to said inner rod, rotational braking means rigidly attached to said outer sleeve such that a braking action may be applied to said rotational friction plate allowing the relative rotation between said outer sleeve and said inner rod to be arrested, a light fixture pivot friction plate rigidly attached to said light fixture, and a light fixture pivot braking means rigidly affixed to said inner rod such that a braking action may be applied to said light fixture pivot friction plate allowing the relative rotation between said light fixture and said inner rod to be arrested; (g) Each said braking means comprising: (i) A cylinder having a partially threaded inner surface, (ii) A biasing screw engaging said threads and having means for manually adjusting the depth of penetration of said screw into said cylinder, (iii) A piston slidably within said cylinder having a bearing surface disposed toward said biasing screw and a disc disposed outward of said cylinder, (iv) A biasing spring disposed within said cylinder between said biasing screw and said bearing surface of said piston, and (v) A braking pad rigidly affixed to said disc and composed of any of the class of materials suitable for producing a frictional effect when forced into contact with a solid surface.