Adjustable door hinge containing coil spring

Claim 1

A spring hinge comprising a pair of hinge leaves disposed side by side and provided with hollow knuckles disposed in axial alignment with one another to form a cylindrical barrel having a knuckle of one hinge leaf at one end and a knuckle of the other hinge leaf at the opposite end, a tubular pivot pin inside the barrel in engagement therewith for holding the knuckles in alignment, plugs rigidly mounted in the opposite ends of the barrel, one of the plugs being provided with an axial passage therethrough, an adjustment member having an outer portion rotatably mounted in said passage and an inner portion projecting from the inner end of said plug, the plug and adjustment member having normally abutting surfaces limiting outward movement of said member in said passage, a coil spring inside said tubular pin with one end connected to said inner portion of the adjustment member and with its opposite end connected to the plug at the opposite end of the pin, the spring pressing said member outwardly against the adjoining plug, and releasable interengaging means normally preventing rotation of said adjustment member in said plug passage, the outer end of said member being provided with means for receiving a tool for turning it in said passage to adjust the tension on said spring when said interengaging means are disengaged.