Patent GB-892860-A (GB)
Title: Tubular lock
IPC: E05B63/04
Filed: 1960-04-05
Abstract: 892,860. Tubular locks. YALE & TOWNE MANUFACTURING CO. April 5, 1960 [April 13, 1959], No. 11961/60. Class 44. A tubular mortice lock for a door D, Fig. 4, having a bolt 14, Figs. 1, 3, withdrawable against a spring 36 by a key applied to a socket 34 comprises a housing 17 having ears 19 at its forward end, a base-plate 12 lying rearwardly of said ears and rotatably mounted on said housing, a decorative front plate 11 of said housing lying forwardly of said ears, the plates having openings 22, 21 for fastening members 23, and means whereby the drawing together of the plates by the members 23 secures said housing to the plates against relative rotation. Such rotation is prevented by engagement of projections 20 on the plate 12 with the ears 19. Prior to the installation in a door the plates 11, 12 are held apart as far as' is allowed by sleeves 24 by the spring 36 so that the ears and projections 19, 20 may disengage to allow relative rotation through 180 degrees between the plates and the housing 17  should the hand of the lock require alteration. The plate 11 may be tilted or pivotally adjusted to fit on bevelled doors. The latch bolt 14. which has a tubular extension 28 receiving one end of a spring 26 normally holding the bolt in an extended position, is adapted to be withdrawn against the spring 26 by a channelshaped retractor bar 31 connected at one end to the extension 28 by means of a bifurcated end each finger 31d, Fig. 5, of which extends around the extension and into an annular groove 28a formed in the extension and which permits relative rotation between the bolt and the bar. The other end of the spring 26 is received in a guide 29 which telescopes in the extension 28 as the bolt is withdrawn. The other end of the bar 31 is bifurcated and pivotally attached by a pin 32 to a pair of crankarms 33 which are formed as integral parts of a U-shaped lever and are adapted to be turned by a spindle (not shown) inserted through the socket 34 in one of the arms. Rotation of the arms 33 in the direction of the arrow, Fig. 3, which arms are pivotally attached to an extension 35 of the housing 17, retracts the bolt. A trigger bolt 15 has an end 15a surrounding and slidable on the housing 29 of the spring 26. When the door on which the lock is mounted is closed the outer end of the bolt 15 is moved inwardly against the spring 36, by engaging the strike plate on the door jamb, such that the end 15a moves towards the rear of the housing 17 permitting a spring (36a) biased finger 31a on the bar 31 to drop down behind a shoulder 28b on the extension 28. Simultaneously the pin 32 drops into a recess 35a formed in the extension 35 thereby deadlocking the bolt 14 against backward movement. The upper surfaces of cam slots 33a in which the pin 32 operates aid in seating the pin in the recess 35a by camming the pin towards the recess. On rotation of the arms 33 in the direction of the arrow, Fig. 3. the pin 32 is cammed out of the recesses 35a by the lower surface of the cam slots 33a to thereby allow the bar 31 to retract the bolt 14 Release of the bolt 15 from the strike plate of the door jamb allows the end 15a thereof to move forward under the influence of spring 36 thereby camming the finger 31a up into the position as shown in Fig. 3 away from the shoulder 28b. The spring 36a fits between two bars 31b, Fig. 3, and 31c which extend between the fingers 31d of the bar 31. Bar 31c projects beyond the end of the fingers 31 d and extends loosely into an annular groove 14a formed in the bolt 14 to provide a pivot for the bar 31 when the bolt is not retracted. The spring 36a is compressed against an annular skirt 14b of the bolt 14. The engagement of bar 31c in the groove 14a provides an auxiliary deadlocking action for the bolt 14 when the pin 32 drops into the recess 35a inasmuch as the simultaneous engagement of bar 31c and the pin 32, in the groove 14a and the recess 35a, respectively, prevents rearward movement of the bolt 14 by force applied to the outer end of the bolt. Thus a second deadlocking action is provided in addition to that provided by the engagement of finger 31a behind shoulder 28b.