bias the hinge assembly to a closed position application_number US 4575193 A description reference is first made to fig1 which shows a shower stall generally indicated at 10 the shower stall 10 has a front bottom wall 12 front side walls 14 and a front upper glass wall 16 extending between the side walls 14 the walls 12 14 16 define an opening 18 which receives a shower door 20 the shower door 20 is pivotally mounted in the opening 18 by a bottom hinge 22 and a top hinge 24 hinges 22 24 both employ the features of the invention and hinge 22 will next be described with reference to fig2 to 5 hinge 22 includes a fixed hinge member 26 in the form of a flat relatively thin rectangular bar hinge member 26 includes a pair of screw holes 28 adapted to receive downwardly extending screws 30 fig1 to secure hinge member 26 to the upper surface 7 of bottom wall 12 hinge member 26 also includes fig2 a central bore 34 extending from a rear surface 36 toward the front surface 38 of the hinge member 26 the bore 34 opens into a square recess 40 sunk into the center of the front surface 38 of the hinge member 26 as best shown in fig2 the square recess 40 snugly accepts the square end 42 of a pivot pin.