US1960032A - Security lock - Google Patents

Description

2 Sheets-Sheet 1 May '22 w34 E. scHMm-r SECURITY LOCK Filed sept. 17. 1952 2 sheets-sheen 2 INVENTQR DMD SCM/wim Patented May 22, 1934 UNITED STATES PATENT OFFICE 2 Claims.

This invention relates to locks and more particularly to locks of the lever tumbler type adapted for doors and like objects whereby they may be securely held when in closed position.

One of the objects of the invention is to provide a lock which can be operated from both sides by a key having two diierent kinds of bits on the same stem.

A further feature is in the provision of means within the lock casing which prevents opening oi the lock with a false key.

Another purpose is to produce a lock operable from one side by a key incapable of operating from the other side.

These important purposes are accomplished by the novel construction and combination of parts hereinafter described and illustrated in the accompanying drawings, constituting a material component of this disclosure, and in which:

Figure 1 is a side elevational view of an embodiment of the invention, the cover plate being omitted.

Figure 2 is a similar view from the opposite side of the lock.

Figure 3 is a side elevational View of a specic form of the key used in connection with the lock.

Figure 4 is a transverse sectional View taken on line 4 4 of Fig. 3.

Figure 5 is a similar sectional View taken on line 5 5 of Fig. 3.

Figure 6 is an enlarged transverse sectional view of the lock taken on line 6 6 of Fig. 1.

Fi/gure 7 is a longitudinal sectional View taken on line 7 7 of Fig. 1.

Figure 8 is a fragmentary sectional view oi the lock casing showing the bolt in a retracted position, the section being taken on line 8 8 of Fig. 6.

Figure 9 is a similar View taken on line 9 9 of Fig. 6, showing the opposite side of the bolt.

Figure 10 is another like View looking on line 10-10 of Fig. 6.

Figure 11 is a View similar to Fig. 9, but showing the bolt in an outward position.

Referring in greater detail to the drawings the lock casing is shown to be comprised of a back plate 15, generally rectangular in profile.

A face plate 17 connects between side walls 18 l9 integral with a rear-wall 20, these walls being of materially lesser height than the face 17.

A cover plate 21 completely covers the walls 18-19 and is secured by screws in the usual manner to studs projecting inwardly from the plate 15.

A bolt 22, slidable in the casing to be projected through an opening in the face plate 17 is provided with a ledge 23 limiting its outward movement by contact with the plate.

The shank of the bolt contains a central longitudinal recess 24 in which operates a pivoted plate 25 pivoted on a stud 26 set in upper and lower elements respectively 27 28 of the shank, and through which are formed longitudinal registering slots, 29-30.

A rectangular stud 31, fixed in the back plate 15, engages the side edges of the slots to act as a guide for the bolt, and also extends upwardly through the cover plate 21.

The stud 31 also passes through a corresponding slot 32 in the pivoted plate 25, this latter slot being straight at its rear edge which is maintained normally against the stud by a flat spring 52 iiXed in plate 25, which is further provided with three spaced notches 33-34 35 in its front edge, these notches being curved with a radius struck from the stud 26, permitting the plate 25 to swing in the manner indicated in Figs. l0 and Plugs 36 are fixed in pivoted plate 25 to extend 'equally through both sides, to maintain the pivoted plate centrally of the bolt shank elements 27 28 and tend to prevent sticking by contact of the superiicial areas.

In the rear edge of the shank element 27 are three notches 37 38 39, and in the mating element 28, are similar notches, 37 38 39, all corresponding in distances apart to the wing notches 33 34-35.

Engageable in the notches of the lower bolt shank element 28 is the hooked end of a tumbler 40, its opposite end being looped around a post 41 Xed in the front portion of the casing, the turnbler being pressed into engaging position by a flat spring 42 coiled about a rectangular stud 43 iiXed in the casing, see Fig. l.

In a similar manner an opposed tumbler 44 has a hooked end to engage the notches 37 38 39 in the shank element 27, the opposite end of the tumbler being looped around a post 45 xed in the rear portion of the casing and pressed into engagement by a iiat spring 46 coiled about a square stud 47 ixed in the casing.

Carried by the tumbler 40 is an inreaching flat plate 48, disposed betweenvthe lower surface of the shank element 27 and casing back plate 15, and having a cam-like opening 49.

A similar flat plate 50 is carried in a like manner by the tumbler 44 to be disposed between the upper surface of the shank element 27 and under side of the partial cover plate 2l, the

`to the tumbler plate 48, spring 42 plate 50 having an elliptical cam-like opening 51.

The width of the bolt shank element 28 is materially less than that of the mating element 27 and formed in its edge, opposite the notches 37-38'-39' are ward recesses 55-56 having angularly bevelled entrances.

Similar ward recesses 57-58 are formed in the corresponding edge of the upper element 27, these recesses registering longitudinally of the bolt but are not in lateral registration due to the different widths of the shank elements and serve a purpose later n apparent.

Formed in the back plate is a key hole 60 having a circular portion 61 from which leads a slot 62 having two lateral notches 63-64 on one side and three lateral notches 65-66-67 on the other, the foot of the key hole being arcuate.

A similar key hole 76 is formed in the partial cover plate 2l, in register with the key hole 60, as may be seen in Figs. 1 and 2.

Set rigidly in the plate 2l is a key guide 68 open at 69 to admit passage of the bits of the key by which the lock is controlled.

This key, shown in Figs. 3, 4 and 5, consists of a round shank 72, preferably having a knurled central portion, the shank being uniform in diameter and provided with ornamental rounded ends 73-74.

Adjacent to the end 73 are two spaced bits 75-76 respectively outer and inner, the outer bit 75 being in excess or the length of the inner bit. On the bit 76 is a single ward 77 midway its length adapted to pass through the recess 67 of the key hole 60, and opposed end wards 78-79 to pass the recesses 63-66.

A space C separates the bit 76 from the outer bit 75, which latter is provided with a single ward 81, registering with the ward 77 and two outer opposed wards 82-83 to pass the recesses 64-65.

At the opposite end portion of the key are two similar bits 7576 having a space 80 therebetween and arranged in a reversed position relative to the shank 72.

it will now be understood that one end of the key is used from the inner side of the lock, through the key hole 60 and the other end through the key hole as directed by the guide 68.

In operation, the bolt being in a retracted position, as shown in Figs. 8, 9 and l0, and it being desired to move the bolt into a locked position from the inner side, as represented by the key hole 60, the key end 74 is inserted and given the usual partial rotary movement.

The bit presses the tumbler plate 50 outwardly, against the spring 46, removing the turnbler a4 from the bolt notch 37; coincidently the bit 76 acts in a similar manner with respect and tumbler 40, releasing it trom the bolt notch 37', thus freeing the bolt.

rThe bit 75', during turning the key, engages the bolt recess 57, while the bit 76' engages the corresponding bolt recess 55, thereby urging the bolt outwardly.

t will be apparent that the lock may be operated irom the other side by reversing the key and inserting it into the lock through the guide 68, whereupon the bolt may be actuated a similar manner.

The use of a spurious key is prevented by the pivoted plate 25, which is moved outwardly, engages the xed post 3l in any of its several recesses, preventing movement of the bolt, while, due to the spaces fio- 662 a proper key may be used without causing movement or the plate 25.

When the bolt has been fully extended the same is positively held by re-engagement of the tumblers in the bolt shank notches. requiring the use of a proper key to unlock as well as to lock the device.

Thus it is apparent that normally the bolt bar is held against movement in the case by both of the master tumblers 48 and 50 and the anti-pick tumbler 25 is in inoperative position. It is also apparent that any instrument or key inserted into the lock from either side and so manipulated as to displace the anti-pick tumbler 25 will positively prevent the bolt bar being moved in the case even though the operator has succeeded in releasing the tumblers 48 and 56 from the bolt bar and engaging the bar.

As changes of construction could be made within the scope of the claims, is intended that all matter contained in the 'foregoing description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.

Having thus described the invention, what is claimed as new and desired to secure by Letters Patent, is:-

l. in a lock of the character described, a case, a bolt bar movable therein and having a plurality of key-engageable portions spaced diiierent distances from the longitudinal center line oi the bolt bar, whereby a certain key bit arrangement nts said key-engageable portions when presented irom one side oi the bolt bar and a reverse key bit arrangement ts said key-engageable portions when presented from the opposite side of the boit bar.

2. In a lock of the character described, a bolt bar having a shank including'two laterally spaced wall portions or unequal width, the edge of one wall portion being disposed outwardly of the corresponding edge of the other wall portion, and each having key-engageable shoulders at said edges, said wall portions at their other edges having tumbler notches, tumblersY engageable with said walls at said notches, an anti-pick tumbler disposed between said wall portions, pivoted on the bolt bar and having an edge disposed outwardly 0f the base of said key-engaging shoulders, a post secured to the case positioned to be engaged by the anti-pick tumbler, when depressed between said wall portions, to lock the bolt bar against movement, and said bolt bar being movable by means of a key adapted to be inserted into the case and having bits adapted to depress the master tumblers to release the bolt bar and t0 engage the key-engageable shoulders to move the bolt bar, and having a recess adapted to receive the anti-pick tumbler to avoid displacing the anti-pick tumbler to lock the bolt bar when the key is manipulated in the case.

EDUARD SCHMIDT.

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