Deadbolt Backset Latch With Interlock

Adjustment of the backset of latches have included slot and pin arrangements in which the latch components are rotated and reciprocated to accomplish backset adjustment (U.S. Pat. Nos. 1,661,454 and 4,372,594) and backset adjustment has also been accomplished using movable pin and spring-loaded pins and pin-receiving recesses (U.S. Pat. Nos. 4,653,787 and 4,602,490).

Broadly, the present invention comprises an adjustable deadbolt latch in which, as a movable housing section is adjustable to various lengths and the bolt train is simultaneously adjustable using a slot and pin arrangement and in which a turnable shuttle element engages and holds a portion of the bolt train in fixed relationship with the stationary housing section during adjustment.

It is a feature of the invention that the turnable shuttle operates only when the bolt train is extended to its lock position and a housing portion turned.

FIG. 1 is a plan view of the deadbolt backset latch mechanism;

FIG. 2 is an exploded perspective view of the mechanism;

FIG. 3 is a partial sectional view through plug and deadbolt showing the 23/8" backset position;

FIG. 4 is a partial sectional view through plug and deadbolt showing the mechanism being adjusted to the 23/4" position;

FIG. 5 is a sectional view along line 5--5 of FIG. 3;

FIG. 6 is a sectional view along line 6--6 of FIG. 4;

FIG. 7 is a partially cutaway side view of the mechanism showing the shuttle disengaged from the bolt;

FIG. 8 is a partially cutaway side view of the mechanism showing the shuttle engaged with the bolt;

FIG. 9 is an end elevational view of the mechanism with the shuttle shown disengaged from the bolt;

FIG. 10 is an end elevational view of the mechanism with the shuttle engaged to the bolt;

FIG. 11 is a plan view of a second embodiment of the invention;

FIG. 12 is an exploded perspective view of the second embodiment mechanism;

FIG. 13 is a longitudinal sectional view through the mechanism with the bolt retracted;

FIG. 14 is a transverse sectional view through the mechanism showing the shuttle disengaged;

FIG. 15 is a partial longitudinal sectional view showing the shuttle engaging the depressible ball; and

FIG. 16 is a transverse sectional view showing the shuttle and ball in contact.

In FIGS. 1-4, backset mechanism 10 includes housing case halves 11a, 11b comprising casing housing 11 connected together through crosspiece 12 projecting from half 11b and located in slot 13 of half 11a. Case halves 11a, 11b which include flat side portions 11c and opening 11d, as assembled are slidably positioned in cylindrical housing 16 with two (2) raised followers 17u and 17l (not shown), each positioned 180.degree. apart in a configured opening 18 u and 18l which are also spaced 180.degree. apart. Opening 18u includes slant side 18s and guide sides 20a, 20b. Also shown is swivel H and back plate l6a and fore plate A.

Turning particularly to FIG. 2, bolt train 19 includes flat-sided deadbolt 21; adjustable bolt adjustment plug 22 and L-shaped bolt train driver 23. Driver tongs 23a, 23b grip ring groove 22a of plug 22 so that plug 22 turns when driver 23 turns. Since driver 23 is housed in housing 11, the turning of housing 11 causes plug 22 to turn. Deadbolt 21 of bolt train 19 is located in housing 16 leaving, due to the flat-sided configuration of bolt 21, spaces 21g and 21h on either side (FIG. 9). Deadbolt 21 includes bolt groove 21a. The effective length of bolt train 19 is changed by axially moving the bolt plug 22 within recess 26 of deadbolt 21 and thereafter locking bolt 21 to plug 22 as hereafter further described.

Deadbolt plug pin 24 projects through bolt hole 24a into bolt internal recess 26 and engages in U-shaped bolt plug track 27. Track 27 includes remote cross groove 27a, near cross groove 27b and longitudinal notch 27c defined by cross walls 27d, 27c and transverse wall 27f. Turnable shuttle 32 includes curved body 33, anchor extension 32a and a deadbolt arrestor piece 32b. Pin 24 rides in grooves 27a, 27b and notch 27c to accomplish backset adjustment. Also shown in FIG. 2 is shuttle 32 which is, at all times, held against axial movement by anchor extension 32a positioned between plates A and 16a (FIGS. 1 and 2).

Backset adjustment is accomplished by first placing deadbolt 21 in its extended position (FIG. 1) through rotating handle H to its forward position (handle H is shown in its retracted position in FIGS. 11 and 13). In its extended position, deadbolt 21 is sufficiently forward to permit casing housing 11 to be partially turned with flat-sided bolt 21 (which is not rotated) entering into housing openings 11d as housing 11 turns (FIG. 10). Cylindrical housing 16 remains fixed, as casing housing 11 including halves 11a, 11b, is turned to rotate shuttle 32 to cause shuttle arrestor piece 32b to move into deadbolt groove 21a (FIGS. 2, 9 and 10). In this position, deadbolt 21 is held against longitudinal movement in either the forward or backward direction. In this housing-rotated position, bolt plug 22 is rotated so that deadbolt pin 24 is positioned in lateral notch 27c permitting bolt plug 22 to be movable axially to either 23/8 or the 23/4 position as desired. To complete adjustment, case halves 11a, 11b are rotated back to their normal position causing shuttle arrestor piece 32b to withdraw from deadbolt slot 21a and pin 24, held by bolt 21, to enter into cross groove 27a or 27b as plug 22 is turned.

During rotation of housing 11 which carries with driver 23, plug 22, blister 17u and its 180.degree. opposite blister 171 moves in openings 18u and 181 respectively. Follower 17u is guided by walls 20a, 20b of 18u in completing the 23/4" setting and 17l is guided by walls 20c, 20d of opening 18l completing the 23/4" setting. Movement of blisters 17u, 17l in openings 18u, 18l provides for backset adjusting of casing 16 vis-a-vis casing 11.

Turning to FIGS. 3-6, deadbolt pin 24 is secured in bolt hole 24a. Pin 24 extends down into bolt recess 26 in which plug 22 is reciprocated and turned through engaged driver 23 to allow pin 24 to reciprocate in notch 27d (FIGS. 4 and 6). Notch 27c is defined by end surfaces 27d and 27e (FIG. 2). Backset adjustment is blocked when pin 24 is in groove 27a or 27b, the two backset positions being 154 " apart.

FIGS. 7-10 illustrate the operation of shuttle 32 which is rotated by housing 11 into and out of bolt groove 21a. When shuttle arrestor 32b enters groove 21a it prevents longitudinal movement of deadbolt 21 during backset adjustment. FIGS. 7 and 9 show shuttle 32 including arrestor 32b withdrawn from bolt groove 21a while FIGS. 8 and 10 show shuttle 32 engaged with bolt 21. Flat-sided deadbolt 22 provides spaces 21g and 21f (see FIG. 9).

Turning to FIGS. 11-16 and the second embodiment, backset mechanism 10', includes housing case halves 11a', 11b' connected together through crosspiece 12' projecting from half 11b', and located in slot 13' of half 11a', Case halves 11a', 11b' as assembled are slidably positioned in cylindrical back plate outer cylindrical housing 16' with followers l7u', 18l' positioned in configured slot openings 18u', 18l'. Also shown is swivel H' and back plate l6a' and for plate A'.

Bolt train 19' includes flat-sided deadbolt 21'; adjustable bolt plug 22' and bolt train driver 23'. Deadbolt 21' of bolt train 19' is located in housing 16' leaving, due to the flat-sided configuration of bolt 21', spaces 21g' and 21h' on either side (FIG. 14). The effective length of bolt train 19' is changed by axially moving the bolt body plug 22' within recess 26' of deadbolt 21'. Adjustment of plug 22' in bolt recess 26' is accomplished by rotating the shuttle 32' to depress ball 37 to cause spring-loaded pin 38a or 38b to move against respective springs 35 and 42 to exit radial passageway 46 in bolt 21' thus allowing bolt plug 22' to clear bolt 21' and thereafter be moved axially in either direction of two-headed arrow (FIG. 13) until one of spring-loaded driver pins 38a, 38b is positioned for release and entry into passageway 46. The depression of ball 37 is accomplished by shuttle 32' (hidden in FIG. 13 but shown in FIGS. 12, 14, 15 and 16). Unlike the first embodiment, plug 22' does not rotate but moves axially as limited by plug notch 47 and pin D fixed in deadbolt 21' and extending into and across notch 47 (FIG. 12). Driver 23' fits loosely in groove 22a of plug 22' to permit rotation of driver 23' with rotation of plug 22'.

Shuttle 32' which includes curved body 33', anchor extension 32a' and a deadbolt actuator piece 32b', is located in space 21g' between flat-sided bolt 21' and cylindrical housing 16'. Shuttle 32' is locked to housing 16' and its integral plate l6a' as anchor extension 32a' engages between back plate l6' and fore plate A'. Since shuttle 32' is enclosed between case halves 11a', 11b' and the flat side of deadbolt 21', the turning of the case halves of housing 11' turns shuttle 32' to bring its indented ball actuator pieces 32b' into engagement with ball 37 and, as there is further turning of case housing 11' ball 37 is depressed to accomplish bolt train 19' adjustment as described above. Plug 22' has annular groove 22a' for receiving in clamping engagement so that rotation of driver 23' rotates plug 22'.

Turning to FIGS. 14, 15 and 16, shuttle 32' with its ball actuator 32b' is shown engaging and depressing ball 37. FIG. 16 shows the ball 37 in the process of being depressed against spring 33, 42. Since body 16 remains stationary (FIG. 16), pin 38a', as shuttle 32' turns further, will clear the shear line 50 defined by the outside cylindrical dimension of cylindrical internal bolt recess 26' and thereafter bolt 22' becomes free to reciprocate for backset adjustment in either axial direction.