US3495425A - Magnetically operating lock - Google Patents

Description

United States Patent l Int. Cl. E05b 19/2 6, 33/00, 47/00 US. Cl. 70276 4 Claims ABSTRACT OF THE DISCLOSURE A key cylinder and a coupling cylinder are each retained in a housing, the key cylinder being freely rotatable therein, and the coupling cylinder being connected to a locking element; both cylinders have matching chambers, and coupling elements are located in the chambers, which are magnetic; upon placement of a key having predetermined zones of magnetization thereon in the key cylinder, the magnetic element will move, if the zones of magnetization on the key match the zones of magnetization on the element, to partly span the two chambers, thus interconnecting the coupling cylinder and the key cylinder to permit operation of the locking bail by the key; various embodiments are disclosed illustrating various structures of intercoupling the key cylinder and the coupling cylinder.

The present invention relates to a magnetic lock and more particularly to a cylinder lock containing therein movable magnetic elements.

Magnetic locks have previously been proposed in which the locking tumblers consist of magnetic pins, movable in radial bores within a housing and a key, or inner cylinder. In the locking position, these pins engage both parts and are retained in their locking position by further magnets, which close off the bores of the housing towards the outside. In order to close such a lock, a key is inserted into the inner cylinder which is arranged to be permanently magnetized, or have permanent magnets supplied thereto. The location of these permanent magnets is such that they are opposite to the locking pins in order to attract the pins into the unlocked position. This requires that the force of the magnets closing off the housing must be overcome by the magnetic force of the key, in turn requiring substantial strength on the key magnets. Further, it is possible to break these pins when using the wrong key, or a screwdriver for example, since the magnetic material usually is brittle.

It is an object of the present invention to provide a magnetic lock which is simple to build, resistant against destruction or forcing, and can be used with an easily magnetized key.

Briefly, in accordance with the present invention, a magnetic lock is provided which consists of a rotatable key cylinder located Within a housing cylinder, separated from the housing by an intermediate cylinder to which the locking bolt is attached. At least one magnetic element, and preferably a plurality of magnetic elements, are movable between a locking and an unlocking position to couple the intermediate cylinder to the key. When the key is removed the intermediate cylinder and the key cylinder are uncoupled so that the key cylinder may rotate freely. Coupling between the intermediate cylinder and the key cylinder is effected by the magnetic elements. These elements are preferably a single body of magnetic material having impressed thereon different zones of magnetization. The zones of magnetization are arranged to match zones of magnetization on the key, In some embodiments the polarity of adjacent zones on the magnetic 3,495,425 Patented Feb. 17, 1970 element and on the key will be similar, so that the magnetic elements are repelled. In the other embodiments, .the zones are dissimilar so that the magnetic elements wil be attracted. The magnetic elements themselves can move within the lock in chambers, cut into at least two of the three cylinders in the lock: the housing cylinder, the key (or inner) cylinder, and the coupling (or intermediate) cylinder. The chamber (or chambers, if provided) in one of the cylinders is large enough to accommodate the entire magnetic elementthe chamber in the other, or matching cylinder, is of sma ler size. When in the freely rotatable (i.e. uncoupled cylinders), or locked position, these elements are all contained within the chamber, or chambers of one cylinder; when in the coupled position in which the key operates the bolt of the lock, the elements project from one chamber into the other and interconnect the two adjacent cylinders together.

If there should be non-coincidence of the predetermined pattern of zones of magnetization of the key with the pattern of magnetization of the magnetic elements-or total absence of the key which is the equivalent of noncoincidence-then the key cylinder will be movable freely without permitting engagement of the key cylinder to the coupling cylinder, and thus to the locking elements which operate the lock bolt.

The magnetic elements may be slidable axially of the cylinder, radially of the cylinder, directly engage the intermediate or coupling cylinder, or engage additional coupling rings. Various internal arrangement of the lock is possible.

The principle of the present invention may be applied not only to cylinder locks, but also to other locks, such as for example sliding locks, and the term cylinder as used herein is intended to cover not only a rotatable unit, but also relatively slidable units having a shape other than round. Ordinarily, the cylinders will be co-axial and rotate one within the other; the cylinders may, however, also be arranged to be axially slidable. And while the key would ordinarily be inserted within the cylinder along the axis thereof, the lock can also be arranged such that the magnetic field of the key influences the locking elements from a different position.

The structure, organization and operation of the invention will now be described more specifically in the following detailed description with reference to the accompanying drawings, in which:

FIGS. 1a and 1b are a schematic cross-sectional view of the magnetic lock in accordance with the present invention, FIG. la being in the uncoupled (locked) and FIG. lb in the coupled (unlocking) position with a key inserted;

FIG. 2 illustrates in schematic form an arrangement of permanent magnets for a key and magnetic elements, and an arrangement of polarity;

FIGS. 3a and 3b are a longitudinal and a crosssectional view, respectively, of an embodiment of the present invention;

Referring now to the drawings: an inner, or key cylinder 6 has a central opening 6a therein, to form a guideway or keyway for the key 1 fitting therein. The circumference of the cylirder 6 is formed with a pair of recesses 6b, located opposite each other. These recesses, or chamber 6b, are large enough to wholly accommodate a magnetic element 2a, 2b therein. Magnetic elements 2a, 2b are in forms of axially extending, elongated longitudinal bars. The magnetic coupling elements 2a, 2b are magnetized to have poles as shown, with opposite poles adjacent each other. The inner cylinder 6 is surrounded by an intermediate, or coupling cylinder 7, which in turn is rotatable within a housing, not shown in FIG. 1. The locking element L (FIGS. 37) which operates the key bolt, or itself forms part of the bolting arrangement of the lock, is attached to this intermediate or coupling cylinder 7. Coupling cylinder 7 is formed with oppositely located chambers, or recesses 7a, matching the chambers 6b in the key cylinder, but of smaller size. They are of such depth that the magnetic elements 2a, 2b can enter into the recesses or chambers 7a only to a limited extent.

FIG. 2 illustrates a longitudinal view of magnetization arrangements for the key 1 and locking elements 2a, 2b. The key may consist of a fiat elongated surface of magnetic material, magnetized as shown in FIG. 2, or of a strip of support material to which permanent magnets are attached. The key is subdivided, artificially, into predetermined zones which are magnetized to have their magnetic orientation in a predetermined pattern. As shown, the pattern alternates, but adjacent zones may have the same magnetic orientation, that is a pole may extend over more than one zone length of the key. Thus, a large variety of combinations can be obtained. The pattern of magnetic orientation of the key is matched by the pattern of magnetic orientation of the locking elements 2a, 2b.

Referring again to FIGS. 1a and 1b, as seen in FIG. 1, opposite poles of the magnetic elements 2a, 2b attract each other. Thus, the magnetic elements 2a, 2b will lie wholly Within the key cylinder 6, which can rotate freely Within coupling cylinder 7 and the lock cannot be operated. If key 1 is inserted up to its end in keyway 6a (FIG. 1b) the magnetic coupling elements 2a, 2b are urged towards the outside, forming a coupling connection between the key cylinder 6 and the coupling cylinder 7. Rotation of the key will thus cause rotation of locking element L, not shown in FIG. 1. Upon removal of the key, the inner elements again attract each other and lock cannot be operated since key cylinder 6 will again rotate freely.

If a key is inserted which has a pattern of magnetization Which does not match that of the lockthat is if an incorrect key is used, some of the zones of magnetization of elements 2a, 2b will be positively attracted to the key, thus overcoming any repelling force and again preventing engagement of the magnetic elements 2a, 2b with a chamber 7a of the coupling cylinder 7. The repulsion of like poles opposite each other upon insertion of a key is illustrated by arrows in FIG. 2; the attraction of unlike poles upon removal of the key by arrows 4 in FIG. 2. Repulsion of the magnetic elements 2a, 2b will occur only when there is exact coincidence of the pattern of magnetization of the key and the pattern of magnetization of the movable magnetic elements 2a, 2b. To obtain proper orientation, a pre-formed keyway, as is customary in locks, can be used. The key 1 itself can be polarized as shown; polarization diagonally, point polarization and circular polarization may also be used, provided that the pattern of magnetic orientation on the key matches the pattern of magnetic orientation on the elements of the lock.

Manufacture of the key itself is simple, particularly if it is made flat as shown in cross-section in FIG. 1b, and magnetized across so that the poles appear on the flat surfaces of the key, providing large magnetic surfaces and a magnetic field of sufiicient strength. The inner cylinder, as well as the coupling cylinder, may be made of any non-magnetic material including plastics.

The invention permits a large number of different construction arrangements internally of the lock, and thus provides good variety and a large number of possible combinations.

Embodiment of FIG. 3: Housing 23 retains a coupling cylinder 27 and a key cylinder 26. A key 20 can be inserted in a keyway formed in inner, or key cylinder 26. The intermediate, or coupling cylinder 27 reaches around the key cylinder 26 and is connected to locking element L. Key cylinder 26 is formed with chambers 21 on either side thereof, in which plate-like, or strip-like magnetic elements 22 are slidable in axial direction. The magnetic elements 22 are formed, on their top, with a bearing surface 22. Magnetic elements 22 are magnetized in such a manner that the magnetic zones of the key 20 coincide with the pattern of magnetization of the magnetic elements 22.

Key cylinder 26 is formed with a radial cavity, in which a coupling element 24 is slidably arranged. Element 24 can slide up and down with respect to FIGS. 3a, 3b. The upper part of coupling element 24 is preferably rounded and a spring 29 presses the coupling element 24 downwardly. Coupling element 24 is further formed with a shoulder 28, matching the bearing surface 22' on the slidable magnetic element 22. The lower part (with respect to FIGS 3a, 3b) of the coupling element 24 engages a recess 27' formed in coupling cylinder 27 when the key cylinder are intended to be locked together. Coupling element 24 is arranged to embrace the key so that it can be operated when the key is inserted.

The key itself is formed with a camming surface 20', forming a depression therein, into which the coupling member 24 can engage, when the key cylinder and the intermediate cylinder are to be coupled together. The camming surface 20 lifts up the coupling element 24 upon withdrawal of the key, and effects disengagement of the coupling cylinder 27 and the key cylinder 26.

Upon insertion of key 20 into the lock, magnetic elements or plates 22 will slide along the axial cavity 21 until the pattern of magnetic orientation of the key and the pattern of magnetization of the magnetic elements 22 match, and the magnetic elements 22 are opposite the proper places of magnetic orientation on the key, and in their proper coupling position. Further, when the key has been completely inserted, the depression formed by camming surface 20' will be opposite the coupling member 24. If the key 20 is the correct one for the lock, magnetic elements 22 will have their engagement surfaces 22' opposite the projection 28 on the operating member 24, permitting the spring 29 to press the operating member 24 downwardly so that it can engage in recess 27' of the intermediate, or coupling cylinder 27, and permit rotation of the cylinder 27 upon rotation of the key 20. Upon removal of the key 20, camming surface 20 lifts operating member 24, engagement of shoulder 28 with the matching surfaces 22' of the magnetic elements 22 bends, and the slidable magnetic elements 22 slide forwardly together with the moving magnetic field of the key. The magnetic elements, now no longer aligned, hold the operating element 24 out of engagement with recess 27'. Coupling of intermediate cylinder 27 with key cylinder 26 is thus interrupted and the keying cylinder turns freely without operation of the coupling cylinder and thus locking element L.

The present invention thus provides a magnetically operating lock for use with a key having zones of magnetization which are oriented in a predetermined pattern. The lock is contained within a housing and is provided with a locking element which operates a bolt, latch or the like. The portions which determine the combination of the lock consist of one or more magnetic elements, or single structural elements such as a bar having predetermined zones of magnetization impressed thereon, matching the zones of magnetization of the key for the lock. These elements do not prevent rotation, or other motion of the key cylinder, but rather, when the key is engaged in the lock, couple the key cylinder, or a portion associated therewith, to an intermediate or coupling cylinder. It is this coupling cylinder which operates the locking element. When the key is removed, or when a wrong key is inserted into the lock, the key cylinder turns freely and there is no engagement by the magnetic element, or elements with the coupling cylinder.

The lock has been described in connection with a cylinder lock, but it may have other Shapes. Thus, while the key may be of the conventional form, that is have a small grip and an elongated flat keying surface, it can have different forms as well, such as a flat strip of material having magnetic zones affixed, or impressed thereon. Such a flat strip of material, rather than being inserted into a keyway or bore within a cylinder, may be placed against a holding element having the same function as the ordinary cylinder in a cylinder lock, namely to retain the magnetic elements; these magnetic elements, by being selectively attracted, or repelled by the magnetic zones on the strip of the key, then can release and oppose element, corresponding to the coupling cylinder.

What is claimed is:

1. Magnetically operating lock for use with a key having zones of magnetization oriented in a predetermined pattern, comprising:

a housing;

a movable key cylinder located in said housing to receive a key;

a coupling cylinder and a locking element associated therewith, said coupling cylinder and said key cylinder being each formed with a matching recess;

a connecting member located in said recess and movable from an uncoupled position wholly within the recess of one of said cylinders to a coupling position wherein said connecting member is partly within the recess of both said cylinders to couple said cylinders together; and

a plurality of magnetic elements, slidable axially parallel to the axis of said key cylinder, said magnetic elements engaging said connecting member to retain said connecting member wholly in one of said recesses when said elements are positioned in the uncoupling position and permitting movement of said connecting member to the coupling position when said elements are out of engagement with said locking member under influence of the magnetic field of the key.

2. Lock as claimed in claim 1 including spring means biasing said connecting member to move into coupling position; said connecting member being arranged transverse to said cylinder and embracing said key.

3. Lock as claimed in claim 2 in combination with a key having a camming surface, said camming surface lifting said embracing connecting member against the pressure of said biasing spring to permit said magnetic plates to move into engagement with said connecting member as the plates slide within the lock under the influence of the magnetic field from the key upon withdrawal of said key from said key cylinder.

4. Lock as claimed in claim 1 wherein said lock has a key side and a rear side, said coupling cylinder embracing said key cylinder from the rear side of the lock.

References Cited UNITED STATES PATENTS 1/ 1946 Stroud -276 1/1961 Hall 70--276 US. Cl. X.R. 70363, 413

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