GB2078843A - Improvements relating to locks and keys - Google Patents

Abstract

A lock and key are disclosed; the lock is a rotary cylinder lock having mounted therein spring-loaded two- part tumbler pins (6, A to K) extending radially of the cylinder core (2) and cylinder housing (1). The tumbler pins (6, A to K) are axially movable by the action of a key (4) in a key channel (3) to an unlocked position whereby the core (2) may be rotated relative to said housing (1). The key (4) has recesses (e.g. 9, 10, 11) formed therein, at least one (10) of which comprises two or more different control surfaces (10a, 10b, 10c) which cooperate with the head (B) of a tumbler pin (6, B) during an unlocking operation; and each head (A to K) of the tumbler pins is adapted to engage a predetermined one, or several or all of said control surfaces (10a, 10b, 10c) of the respective recess (10) so as to locate the tumbler (6, B) in a position at which the relative rotation of the core (2) and housing (1) is permitted. <IMAGE>

Description

SPECIFICATION Improvements relating to locks and keys This invention relates to rotary cylinder locks and keys therefor.

Rotary cylinder locks having spring-loaded twopart tumbler pins mounted therein and extending radially of the cylinder housing and cylinder core, which pins are movable axially by the action of a key in a key channel in the core to an unlocked position whereby the core can be rotated relative to said housing, are known. In certain locks of this kind the different locking configurations are obtained primarily by arranging the recesses in the side surfaces of the keys with different depths and the inner pins of the two-part tumbler pins with different lengths.

The number of locking configurations can be further increased by making the distances between the individual tumbler pins of different lengths.

Moreover, the axial spacing of the first tumbler pin from the key stop on the end face of the inner cylinder can be varied.

From CH-PS 432 279, it is also known to increase the number of locking configurations still further by varying the radial spacing of the key channel from the outer surface of the cylinder core.

In locking systems for large buildings such as factories, hotels or banks, in which all or the majority of the locks are unlocked by master keys and wherein individual groups of locks and/or individual locks are opened using the master key and subsidiary keys or individual keys which differ from one another, the number of locking configurations which can be obtained by the known methods referred to hereinbefore is often insufficient.

Therefore, in locking systems of this kind, it is often necessary to omit tumbler pins in some of the locks, i.e. to provide only some of the axial holes with tumbler pins. However, this considerably reduces the degree of security of a lock.

According to one aspect of the present invention I provide, in combination, a rotary cylinder lock having mounted therein spring-loaded two-part tumbler pins extending radially of the cylinder core and cylinder housing, the tumbler pins being axially movable by the action of a key in a key channel in the core to an unlocked position whereby the core may be rotated relative to said housing; and a key insertable in said key channel and adapted to move said tumblers axially to said unlocked position; wherein said key has recesses formed therein, at least one of which recesses comprises two or more different control surfaces which cooperate with the head of a tumbler pin during an unlocking operation; and wherein each head of the tumbler pins are adapted to engage a predetermined one or several or all of the said control surfaces of the respective recess thereby to locate said tumbler in a position at which the relative rotation of the core and housing is permitted.

It is, indeed, already proposed from CH-PS 524749 to provide the recesses in the side surfaces of flat keys from the inside to the outside with a plurality of tumbler control stages located side by side. However, this construction is for an entirely different purpose. The different tumbler control stages are intended to cooperte with tumblers which each consist of a plurality of individually sprung individual pins mounted coaxially inside one another.

The previous proposal does not envisage the use of different tumbler pins whose heads cooperate only with, for example, one of the control stages.

In order that the invention may be more fully understood, embodiments in accordance therewith will now be described, by way of example only, with reference to the accompanying drawings, in which: Figure 1 is a longitudinal section through a rotary cylinder lock with the key inserted, in which some of the recesses in the key comprise a number of different control surfaces for the associated tumbler pins; Figure 2 shows the tips of a variety of tumbler pins which are adapted to cooperate with a recess in the key shown in Figure 1; Figure 3 shows a portion of a key with a modified recess adapted to cooperate with some of the tumbler pins according to Figure 2; Figure 4 shows the tips of a variety of tumbler pins which cooperate with another recess in the key shown in Figure 1; Figure 5 shows a portion of a key with a modified recess for some of the tumbler bolts shown in Figure 4;; Figures 6a, 6b are respectively a plan view and a longitudinal section through a portion of a key with recesses of different configurations; Figure 7 shows a perspective view of the blade of a flat key with recesses of different configurations; and Figure 8 is a cross section through a key with recesses for tumblers extending perpendicularly and diagonally relative to the key surfaces.

The cylinder lock shown in Figure 1 comprises a stationary cylinder housing 1 in which a cylinder core 2 is rotatably mounted. A key 4 is shown already inserted in the key channel 3 of the cylinder core. The parts 1 and 2 have radial bores 5 in which two-part tumbler pins are mounted for axial displacement. The inner pins are marked with the letters A - K. The outer pins 6 differ from one another only in their differing lengths. Also located in the bores 5 are springs 7 which rest against a sleeve 8 and urge the sleeve 8 against the outer pins 6 which in turn urge the inner pins A - K radially inwards against the surfaces of the key 4.

The key 4 partly comprises conventionally drilled recesses which are designated 9 and may each comprise a control surface at different depths. The inner pins A, C, H and K engage in the drilled recesses 9.

Reference numeral 10 denotes a recess in the key 4 which has three different control surfaces 10, 1 Ob, 1 Oc for inner pins.

Figure 2 shows the heads of seven different inner pins B1-B7, all of which are cooperable with recess 10 so that the respective tumbler pins are displaced to an unlocking position. The pin B5 corresponds to the pin B in Figure 1. However, if the recess 10 in the key 4 is altered to adapt the configuration shown in Figure 3 by omitting the control surface 1 0c, the key is only able to cooperate successfully with the inner pins B2, B3 and B4 (that is can be displaced to the unlocking position). Thus, locks which are provided with inner pins B1, B5, B6 and B7 cannot be opened by keys 4 which have a recess 10 in the appropriate position(s) as illustrated in Figure 3.

If a recess in the key 4 is constructed like the recess designated 11, pin D the head of which may have e.g. any one of the ten different forms D1-D1, shown in Figure 4, can cooperate successfully with this recess 11. The bolt D2 corresponds to the inner bolt designated Din Figure 1. If the recess 11 in the key 4 is altered, to the form shown in Figure 5, for example, such a key can only cooperate successfully with the inner bolts D5 and D6. By making other corresponding alterations to the recesses 10 and 11 and the heads of the corresponding inner bolts, it is possible to provide a very large number of additional locking configurations. It will be apparent that, the other side of the key may also be provided with recesses having different control surfaces. The recess cooperating with the pin G corresponds, for example, to the recess 11 (Figure 1).

The construction of the recesses can be further modified if the bores 5 in the cylinder are not circular but angular, e.g. rectangularortriangularforexam- ple, and the tumbler pins are constructed accordingly so that they cannot rotate in the axial bores provided therefor. The recesses in the keys 4 may then take the form shown in Figures 6a and 6b.

Admittedly, the provision of recesses of this kind in the keys would be a complicated operation, as they cannot be drilled or milled but would have to be broached or pressed. Figure 7 shows a key which comprises a plurality of different recesses which are also provided on the surfaces of the narrow side. The cross section of a key in Figure 8 shows that it is also possible to provide recesses 12 fortumbler bolts which are directed diagonally relative to the side wall of the key.

Where a plurality of locks and keys, in accordance with the invention are provided, the recesses of the individual keys may be identical in construction but the lengths and heads of individual tumbler pins may be different. On the other hand, the recesses in the individual keys may be of different depths and shapes.

It should be apparent that keys with a plurality of control surfaces, particularly with those shown in Figures 6,7 and 8, would be difficult to copy by unauthorised persons, and this again increases the security of the cylinder considerably.

Claims (9)

1. In combination: a rotary cylinder lock having mounted therein spring-loaded two-part tumbler pins extending radially of the cylinder core and cylinder housing, the tumbler pins being axially movable by the action of a key in a key channel in the core to an unlocked position whereby the core may be rotated relative to said housing; and a key insertable in said key channel and adapted to move said tumblers axially to said unlocked position; wherein said key has recesses formed therein, at least one of which recesses comprises two or more different control surfaces which cooperate with the head of a tumbler pin during an unlocking operation and wherein each head of the tumbler pins are adapted to engage a predetermined one or several or all of the said control surfaces of the respective recess thereby to locate said tumbler in a position at which the relative rotation of the core and housing is permitted.

2. The combination of Claim 1, wherein the key comprises also at least one recessed bore with a single control surface.

3. The combination of Claim 1 or 2, wherein at least one recess in the key comprises concentrically arranged control surfaces.

4. The combination of Claim 1,2 or 3, in which at least one of the tumbler pins is of angular cross section(s), and wherein the respective recess(es) in the key is/are constructed with correspondingly angular cross section(s) with stepped control surfaces or as parallel elongate recesses.

5. A key for a combination as set forth in Claim 1, comprising a blade portion for insertion into a key channel of a lock, and recesses formed in said blade portion for cooperation with respective tumblers of the lock, at least one of said recesses having two or more different control surfaces adapted to cooperate with the head of a tumbler pin.

6. A rotary cylinder lock for a combination according to Claim 1, said lock having mounted therein spring-loaded two-part tumbler pins extending radially of the cylinder core and cylinder housing, the tumbler pins being axially movable by the action of a key as defined in Claim 5, into a key channel in the core to an unlocked position whereby the core may be moved relative to said housing; each head of the tumbler pins being adapted to engage a predetermined one, or several or all of the said control surfaces of the respective recess during an unlocking operation thereby to cause the tumbler pins to be located in a position at which the relative rotation of the core and housing is permitted.

7. A combination according to Claim 1,substan- tially as described herein in the accompanying drawings.

8. A key, substantially as described herein in any one of Figures 1,3,5,6,7 and 8 of the accompanying drawings.

9. A lock, substantially as described herein with reference to any one of Figures 1, 2 and 4 of the accompanying drawings.