GB592984A - Spring catches - Google Patents

Abstract

592,984. Catches. WHEELER, A. F. March 19, 1945, No. 6876. [Class 44] A catch bolt of the spring-pressed ball or plunger type which can be locked comprises a two-part bolt separated by the spring, and locked by a cam turned about its axis by an actuating knob so that it engages the rear abutment member of the two-part bolt and moves it up to the front part. For example, a cylindrical casing 2, which houses a bolt, spring, abutment member and rotary locking member, is fitted into a mortice in a door ; a front plate 1, with a hole for the bolt, is secured to the door by screws ; a recessed keeper-plate is screwed to the jamb. A bolt 6 with a retaining shoulder 12 has a domed head 7 and is recessed at the back to receive a spring 9 ; the other end of this spring is housed in a recess 10 in an abutment member 11. An actuating knob 13 is mounted on a shaft 14 which passes through a plate 15 let into the door ; the bottom end 16 of the shaft is square, and passes through the casing 2 into a square recess 17 in a rotary locking member 18 which has a cam groove 19 in it into which passes a tongue 20 on the abutment member 11. If the knob 13 is turned through 180 degrees in either direction, the abutment member 11 is driven up against the bolt which is thus locked.