US140377A - Improvement in locks for doors - Google Patents

Description

T. KRO M EB. Locks, for Doors, &c.

Patented July 1, 1873.

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UNITED STATES A LPrrrrnv'r OFFICE.

THEODORE KROMER, OF FREIBURG, GRAND DUCHY OF BADEN IMPROVEMENT IN LOCKS FOR DOORS, &c.

Specification forming part of Letters Patent N 0. 140,377, dated July 1, 1873; application led April 17, 1873.

To all whom it may concern:

Be it known that 1,'1HE0D0RE KROMER, of Freiburg, in the Grand Duchy of Baden, have invented an Improvement in Locks; and do hereby declare that the following description, taken in connection with the accompanying sheet ot' drawings hereinafterreferred to, forms a full and exact specification of the same, wherein I have set forth the nature and principles of my said improvement, by which my invention may be distinguished from others of a similar class, together with such parts as I claim and desire to secure by Letters Patent,

that is to say- My invention has reference to the construction of locks for which Letters Patent of the United States of America were granted to me' on the 19th of September 1871, No. 119,036.

My present improvement on such locks is represented on the accompanying drawings, in which Figure 1 shows a front view of the lock with the cover-plates removed, showing the sliding bolt in the unlocked position. Fig. 2 shows the sliding bolt and latch in the locked position. Fig. 3 shows a section on line X X, Fig. 1. Fig. 4 shows a section on line Y Y, Fig. 1. Figs. 5 and 6 show respectively a plan and a section of the key; and Fig. 7 is a similar section to Fig. 4, showing a modified construction of the notched or grooved sliding pins to adapt the lock for use as a combination lock without a key.

One part of my invention has reference to the construction of the notched sliding pins and key. The sliding pins a (Figs. 3 and 4) are formed with a tapering or conical projection, a, on their front ends, which, when the pins are in the forward or locked position vare situated in holes b1 ot' small diameter formed in the projection b2 of the casing b, as shown at Fig. 3. The pins c of the key c (Figs. 5 and 6) are formed with tapering or conical recesses at their front ends, as shown, which, when the key is inserted into the lock for pushing back the sliding pins t onto the tapering ends a of the latter. The recess of each key-pin is made of a different depth and taper, so that the ends of the sliding pins (which are all made of the same length and taper for one lock) enter the recesses of their respective key-pins to varying depths. By this arrangement it is rendered very difficult to ascertain the distance to which the sliding pins have to be pushed in, in order to brin gall the deep or real grooves or notches thereof into position for unlocking, and it is also rendered very difficult to take a proper impression of the key for the purpose of making a false key, andgthus the probability of the lock being pickedis rendered very remote. Another part of my invention consists in providing in the casing of the lock, below each sliding pin, a pin, d, (Fig. 4,) fitting into a recess in the casin g and pressed upward by a spring, d', so as to catch with Aits upper end into the false or real grooves or notches of the sliding pin a. By the action of these spring-pins in catching into and pressing against each groove of the sliding pin as this is slid back for the purpose of bringing the real groove into the position for unlocking, it is rendered very difficult, if not impossible, to feel when the hinged latch e falls with itsvknifeedgesc1 into the real groove of the sliding pin in attempting to pick the lock. Another part of my invention has reference to the sliding 'boltf (Figs. 1 and 2) ot' the lock and its mode of operating in combination with the hinged latch e. The latch, instead ot' having the projections upon its outer end, described in my beforementioned patent, is simply provided with an inclined face, e2. The sliding bolt f has on its lower face a spring-stud, j", which when the latch e is in the raised or locked position and the bolt f is also in the locked position, as atFig. 2, projects in front of the inclined face of the latch, and thus prevents the bolt f from being slid back from its locked position.

Ou the latch c falling into the unlocked position (shown in dotted lines at Fig. 2) by the introduction of the key, its upper face is just below the spring-stud f1, and the sliding boltf can consequently be slid back into the unlocked position by means ot' the lever and handle at g. The sliding bolt j' is furthermore provided with a stud or projection, f2, which, on the backward motion of the bolt, presses against the inclined end face c2 ot' the latch, and thus raises the same up so as to allow the sliding pins a to spring forward into the locked position. As the latch is thus raised up the spring-stud f of the bolt f is pressed upward thereby, as shown in Fig. 1,

and on the boltfbeing again slid forward into the locking position the spring stud, after passing the end of the latch e, again springs down in front of the same, thus locking the bolt, as before described.

In order to keep the knife-edge el of the latch c raised out of the false notches of the sliding pins, when in the locked position, so as to facilitate the pushing back of the sliding pins by means of the key for unlocking, the springstud f1 is, by preference, formed with an inclined face, as shown, which is made to press against the inclined face e2 of the latch e, so as to raise it, by means of a spring, h, fixed to the casing of the lock, which tends to press the bolt f backward, when in the locked position, as shown in Fig. 2. In this case, after the introduction of the key for unlocking, the bolt f must first be pressed slightly forward against the action of the spring h by means of the handle at g, in order to free the latch e from the pressure of the stud f1, whereupon the latch will fall into the unlocked position, and the bolt f can then be slid back.

The above-described lock may be adapted to act as a combination lock, and opened Without the use of a key. For this purpose the springs to the grooved sliding pins a are dispensed with, and the front ends of the sliding pins are extended so as to project through the `holes b1 of the casing, as shown at c2, Fig. 7, and the projecting ends are provided with knobs whereby the pins a can be slid back-- ward and forward by hand. As the springpins d, by springing into the grooves or notches of the sliding pins c, will act as ratchets in retaining them in any position into which they are moved by hand, it will be seen that the operator, knowing the position of the real groove or notch relative to the false grooves in each of the pins a, can readily bring each of the latter successively with their real grooves in correct position for the knife-edge of thel latch e to enter thein for unlocking, by counting thc number of times that the spring-pin catches into the grooves while he is moving the sliding pins. The relative positions of the sliding pins a, (the real grooves or notches of which have a dii'erent position in each pin, as described in my before-mentioned patent,) may be changed at will by removing the back plate z' of the casing, so that a number of different combinations, depending on the number of sliding pins in the lock, may be obtained, whereby the picking of the lock will be rendered as difcult as in any other known construction of combination locks.

Having thus described the nature of my invention, and in what manner the same is to be performed, I claiml. The notched or grooved sliding pins a, with tapering or conical ends al, operating in combination with the key c, with pins cl having conical or tapering recesses, substantially as and for the purposes hereinbefore described.

2. The spring-pins d operating in combination with the sliding pins a, substantially as and for the purposes hereinbefore described.

3. The sliding boltf with spring-stud f1, and stud or projection f2, operating in combination with the hinged latch e with inclined face e2, substantially as and for the purposes hereinbefore described.

4. The spring l1., operating in combination with the sliding bolt f, spring-stud f1, and hinged latch e, substantially as and for the purposes hereinbefore described.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses this 29th day of January, 1873.

'IHEODORE KROMER.

Witnesses HEINRICH SPITZ, ERNST SCHMITT.

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