Abstract: An impressioning key for making an impression of the tumblers of a lock comprises a key blank having a main portion of relatively hard material with a recess in an upper forward edge portion. A tumbler engaging portion consisting substantially wholly of lead is secured to the main portion in the recess, the tumbler engaging portion being a solid pre-shaped body of lead filling the recess.

Abstract: For increased security the key (2; 40; 44) has one or more blade portions (43; 45; 46; 5, 6). The longitudinal central plane (A, B) of the or each blade portion is offset from the guide region (42; 7) running along the back edge of the key shaft (3). Furthermore, the or each blade portion is connected to the guide region by means of a bridging portion (14, 14') which forms an obtuse angle (alpha) with the guide region, as well as forming an obtuse angle with the blade portion. In one preferred embodiment two blade portions (45, 46; 5, 6) are provided; they may be of the same cross-sectional shape (FIG. 2) or symmetrical (FIG. 11). The blade portions and guide region may be divided into two portions to provide partner keys (FIG. 12).

Abstract: An ignition key consists of two structural units which are detachably connected to each other. One of the structural units contains the transmitter electronics and the key shank, while the other structural unit contains the battery and a button for connecting the battery to the transmitter electronics. The attachment of the two structural parts to each other is effected by means of dovetail guides.

Abstract: A key for a lock of the plunger operated type in which an elongated housing has an internal axially movable plunger which releases locking elements when moved toward the open end of the housing, said key having a body with elongated fingers extending forwardly from the housing and an elongated mandrel disposed between the fingers. A finger depth limiter or spacer is disposed at the rear end of the fingers and protrudes forwardly from the foremost face of the key housing for abutting a portion of the lock to limit the distance the fingers can extend into the lock. In one embodiment of the invention an axially adjustable cap is mounted on the forward end of the housing to allow adjustment of the amount the spacer projects from the housing.In one embodiment of the invention internal structure is provided that allows the fingers to shift forwardly a predetermined distance if the forward end of the housing is removed by grinding in an effort to modify the key for use in locks with which it is not intended for use.

Abstract: A combination key includes a hollow head, a hollow stem connected to the head and a plurality of teeth mounted on racks longitudinally movable in the head and stem. The racks are in meshed engagement with toothed control wheels which are mounted in the head and emerge partially to the outside. The control wheels are located in the head next adjacent the stem. The length of the head is at least equal to the length of the stem so that the racks can be accommodated in the head when the teeth are in a position of maximum retraction.

Abstract: A locking key, designed to preserve an indication of the lock-shifting (opening or closing) operation last performed, has a shank with an extension shaft rotatably received in an adjoining head, the relative rotation of the shank and the head being limited to 90.degree. or 180.degree. by a retaining pin in the head coacting with a part-circular recess on the shaft. The pin and the recess also serve to hold the head in a fixed axial position with reference to the shank. A spring-loaded detent in the shaft or elsewhere inside the head serves to index the two key portions in either of their limiting relative positions.

Abstract: A key assembly which can be assembled to a specific code by snapping together the different parts of the key assembly. The key assembly includes a tubular, cylindrical barrel which has a plurality of spaced apart elongated grooves formed in the exterior surface of the barrel. A hole connects with each groove. A pin is to be mountable within each hole. An insert selected from a grouping of a plurality of different lengths of inserts is to be mounted within each groove with the pin for that groove being located within an appropriate opening formed within the insert thereby longitudinally fixing in position the insert with respect to the groove. A collar is then exteriorly mounted on the barrel about the inserts and fixed in position thereby preventing disengagement of the inserts from their respective grooves. A handle is mounted on the barrel.

Abstract: A plunger type lock comprising a barrel with an axial bore, locking members in the form of balls housed in the barrel wall and extensible outwardly from the barrel by a plunger axially slidable within the barrel bore, at least one further ball housed in an opening in the wall of the plunger and extensible outwardly therefrom and a peripheral groove on the inner wall surface of the barrel for receiving the further ball, the further ball being forceably moved and held in the barrel's groove by an incorrect key, instrument or an implement to prevent and resist movement of the plunger whenever an unauthorized attempt to operate and open the lock is made.

Abstract: A key with key bit and separate handle, the end of the key bit extending form-lockingly into a channel in the handle, the channel being directed towards a narrow side of the handle. A disengageable insertion detent is provided for locking a bit to the handle, wherein a construction is provided which is simple to manufacture, advantageous for assembly and stable in use.

Abstract: A slide action key shield to hide and protect a key's tumbler cuts and then, on demand, retract to fully expose the tumbler cuts when opening a lock is disclosed. A double capped pin is fixed through the key near the midpoint along the key's length such that each capped end protrudes through a respective longitudinal face slot on the shield to allow the shield to movably cover one half of the shaft of the key or the other. The shield resembles a longitudinally extended sheath open at both ends which conforms to the shape of the key. One end of the shield is flat so that the shield may be easily pushed back by the lock face while the other end is rounded and given side openings to fully retract over the key head without any sharp edges protruding. If the key head is held by a key ring, the retracted shield will be returned by the force of gravity to cover the tumbler cuts when the key is left to hang after use.

Abstract: A key for a lock of the plunger operated type in which an elongated housing has an internal axially movable plunger which releases locking elements when moved toward the open end of the housing, said key having a body with elongated fingers forwardly from the housing and an elongated mandrel disposed between the fingers. A spacer is disposed at the rear end of the fingers and protrudes forwardly from the foremost face of the key housing for abutting a portion of the lock to limit the distance the fingers can extend into the lock. The housing has a head portion which is axially adjustable in relation to the spacer to vary the amount the spacer projects forwardly from the housing.In one embodiment of the invention internal structure is provided that allows the fingers to shift forwardly a predetermined distance if the forward end of the housing is removed by grinding in an effort to modify the key for use in locks with which it is not intended for use.

Abstract: A locking key, designed to retain an indication of the lock-shifting (opening or closing) operation last performed, has a head and a shank interconnected by a screw coupling with limited axial play enabling their relative rotation through 90.degree. or 180.degree.. The shank and its bit can thus be positively entrained for a lock-opening or a lock-closing motion only after the head has arrived in one or the other limiting angular position relative thereto. When the idle rotation of the head is 180.degree., the relative angular position of the two parts can be indicated by special markings thereon.

Abstract: A bilateral key for a cylinder lock which has more than one row of tumbler pins thereby requiring a key having a number of generally parallel tumbler activation edges corresponding to the number of rows of tumbler pins. The key is formed of blade components having an exterior end and an operative end with an edge containing projections and depressions and a means for attaching the blade components securely together so that the edges are aligned to cooperatively form the lock combination of the cylinder lock.

Abstract: A magneto-electronic lock includes a key body having a magnetic combination. In the interior of a receiver of the key body are arranged magnetic detectors, a bolt, and an electronic circuit device connected between the bolt and the detectors. Positive and negative magnetization devices cooperate, depending on the position thereof, in opening, closing or blocking an electronic circuit including an electric opening pulse of a gate. A device determines the electric continuity both in the key and in the receiver thereof. An electric derivation device opens a code. Passive positive and negative relays are in combination with positive and negative magnetic elements. Positive and negative magnetic devices have potentials to act on the passive relays in the contact threshold.

Abstract: The invention is a unibody key with lateral grooves on one side or both sides of the shank of the key. The lateral grooves are of an irregular pattern and are cut at a depth such that the key can be snapped off along the lateral groove. The snapped-off portion ofthe key can be inserted in a lock. By inserting the snapped-off portion in the lock, only a key which will mate with the irregular pattern of the snapped-off portion will give proper alignment for a key to open such lock. By such operation, the key necessary to open the lock is easily, quickly and effectively changed.

Abstract: A key kit for opening tumbler locks has a key member with a shaft insertable into a tumbler lock, the shaft having a series of longitudinally-spaced recesses into which the tumblers in the lock can respectively enter. A foil of impressionable material is removably positionable on the shaft over the recesses, and a tumbler displacing member is insertable into the lock with the shaft and foil to displace the tumblers without the tumblers engaging the foil. The tumbler displacing member being removable from the lock after the shaft and foil have been inserted therein to enable the key member to be manipulated to cause the tumblers to make impressions in the foil corresponding to the key shape required to open the lock.

Abstract: A lock of the type having an elongated housing open at the rear end with internal operating mechanism to release locking means, in which the mechanism comprises a collar which is spring biased forwardly and a locking stem mounted in the collar and spring biased rearwardly in relation thereto. The insertion of an operating tool causes movement of the stem forwardly a predetermined amount, allowing the tool to engage the collar. However, the insertion of a picking tool into the collar forces the stem forwardly in relation to the collar, a greater distance increasing the overall length of the mechanism to an extent that even when the collar is moved rearwardly as far as possible, the forward end of the stem does not move rearwardly far enough to release the locking means. In one embodiment of the invention, the end of the stem protrudes far enough that operating tools normally used for this type of lock cannot be used to open the lock.

Abstract: The invention relates to a cylinder-lock having a flat key comprising a shank having at least one profile longitudinal groove extending from the end thereof to accommodate a rib in the key-channel of the cylinder-lock, said shank including fixed key bits adapted to index pin-tumblers in the cylinder-lock, said key including in the area of the wide side of the shank an additional movable key bit, said movable key bit being adapted to be controlled by a shoulder in the key-channel such that when the key is inserted it induces an auxiliary tumbler into a position which allows the cylinder core of the lock to be rotated.

Abstract: A key rotatably supported in a mounting and capable of being brought into engagement with a lock is held in the correct orientation for engaging the lock by being locked to the mounting by a retractable sleeve. Only when the mounting is brought into engagement with the lock does a portion of the lock engage the sleeve and push it back relative to the mounting to free the key for rotation. The mounting may be on a moveable part of a machine guard with the lock on a fixed part and controlling operation of the machine.

Abstract: A keying process is provided for use in hotels or motels in conjunction with resettable room locks, so that an immediate indication is provided by the key itself as to whether it is the current key for the lock of a particular room. The key is provided with a serial number which identifies the key so that it may be grouped with its duplicates. The key is also provided with a removable plug which identifies the particular room whose lock has been set currently to accept the key. Two, or more, differently colored plugs are provided for each room, and each time the lock of a particular room is reset to accept a new key, the new key is provided with a room-identifying plug of a different color from the previous key. The key slots at the hotel or motel desk may be provided with correspondingly colored lights, or other color indicators, and the color indicator corresponding to the color of the current plug is activated for each slot.

Abstract: A mechanical magnetic key operated door lock structure particularly adapted for use in hotel locksets. An occupancy indicator is incorporated in the lock structure to indicate that the lockset is locked from the inside, thus insuring privacy for the hotel guest. In addition, means operable from outside the lock structure is provided for changing the combination of the lock so that a newly arriving guest may be provided with a key having a different combination from that used by the previous guest.

Abstract: Exchangeable key covers, and a related system and method, each key cover at least partially enclosing the proximal end of a hotel or like key, each cover being preferably formed of synthetic resinous material, such as polyethylene, and removably force-fit over the proximal end of the key to display room identification indicia and, if desired, other indicia, whereby no key interconnecting chains, tags or the like are required and the key covers are easily and accurately exchanged between keys in correspondence with rotation of the locks.

Abstract: A flat strip section fits in width and height into a keyhole and has non-operable teeth extending from the top and from the bottom. One end of the flat strip section is anchored in one part of a two part gripping stud. The second part is separably connectable to the first part by a detent connection.

Abstract: An adaptor for attachment to a plunger lock unlocking tool of a type which grasps the external surface of the unlocking pin of a plunger-type lock and pulls the pin to the unlocking position, said adaptor enabling the tool to be used to unlock a plunger lock of the type in which the unlocking member is a hollow pin which is grasped internally for pulling to the unlocking position.

Abstract: A key assembly for operating a coded security system is structured with a plurality of information carrier members mounted on a longitudinal member of the key assembly and angularly arranged thereon to define a code for a security system operated by the key. Alteration of the code is effected by changing the relative orientation of the information carrier members by threadedly loosening the longitudinal member upon which the carrier members are held, readjusting the position of the carrier members and tightening the longitudinal member to hold the information carrier members fixed in a desired relative position defining the code.

Abstract: A lock system has an elongated key provided with a plurality of permanent magnets spaced axially and angularly apart along the key in a predetermined magnet array. A cylinder having no moving parts defines a passage generally complementary to this key and provided with a plurality of magnetic-field detectors at least some of which are arrayed to be in line with the magnets of the key when it is inserted into the passage. An electronic circuit is connected to these detectors and to an electrically operable latch and is programmed to open the latch when those detectors that are in line with the permanent magnets change state in a manner indicating that they are juxtaposed with the respective magnets, but not when one or more detectors out of line with the magnet array are similarly subjected to a magnetic field.

Abstract: A cylinder (10) which is highly pick-resistant and also highly resistant to other means of forced entry is provided. The cylinder is of a unique hemispherical construction, involving a hemispherical shell (12), hemispherical plug (13) and hemispherical plug insert (14). In a preferred embodiment, the keyway (28) includes two keyways (23, 25). The key is of a correspondingly complex configuration including a generally circular handle portion (28) and two generally semicircular tumbler pin actuating portions (36 and 37). The hemispherical configuration and the multiplicity of keyways renders it particularly difficult to pick the lock.

Abstract: A covered-grip key includes a flat head wherefrom extends an elongated shaft. In the head there are formed a pair of spaced apart holes interconnecting the two faces of the head and therethrough the joining portions of the two layers covering the two faces of the flat head extend.

Abstract: A cylinder which does not have a plug but has selectors and cooperating pin tumblers controlled thereby under influence of a key which is thrust rectilinearly into the key way and which selectors are actuated by a bolt or the like.

Abstract: A plunger-type (barrel) lock has a spring loaded plunger which can only be properly retracted by the use of a key having a central rod, enlarged end sliding member and outwardly moving fingers for gripping engagement within a socket (cylinder bore) of the plunger. A movable, spring-biased eyelet is positioned adjacent the socket, such that an unauthorized key or tampering tool will grip the eyelet, rather than the plunger socket, failing to open the lock. The key has a toggle type operating lever including a tension relief element in the form of a spring, coacting with an internal collar of the key to allow some axial movement of the key's operating elements. Use of the collar allowing axial movement of the key's operating elements and complementing socket diameter of the plunger within the lock can provide security lock combinations for the user(s).

Abstract: A conventional keyed, pin-tumbler lock has an abutment portion formed on the key axially adjacent one of the key notches at the side thereof axially inward of the lock cylinder which normally axially obstructs that lock pin when the key is properly inserted in the lock cylinder key slot to prevent normal withdrawal of the key from the lock cylinder while still permitting free rotation of the lock cylinder by the key in its normal locking and unlocking movements. A key removal member is axially insertable into the key slot adjacent the key within a key axial recess and has a leading angled surface portion terminating axially in a raised surface portion which progressively move and ultimately retain that particular pin from its key pin notch and the key abutment portion obstruction, thereby permitting normal key removal from the lock cylinder.

Abstract: Attempts to pick the plunger-type (barrel) lock disclosed are frustrated by the necessity of holding one axially movable part in place against the force of a spring while retracting another axially movable member to open the lock. The key that opens the lock has a central pin stationary in use for holding back a position while radially spreading fingers frictionally engage and thereby permit withdrawal of an axially movable cylinder coaxial with the piston. A frangible member is provided for installing the lock without using the special key so that the number of keys can be strictly controlled. The key will open not only the lock of this invention, but also other kinds of plunger-type locks in common use by gas and electric utility companies.

Abstract: A lock having a key-actuated rotary barrel. Said key comprises a holding head axially slidably mounted on a body which head has a radial abutment. The lock has a key entrance surface spaced from the key entrance of the barrel and said surface has a key inserting opening having at least one radial abutment cooperable with said radial abutment of the key head for an axial position of the key head with respect to the key body.

Abstract: A lock of the type having an internal plunger with a stem for being gripped by a tool to pull the stem axially to release locking means, in which said stem has a separate portion protruding from the rear end which is spring biased against the forward portion of the stem. When attempts are made by unauthorized persons to open the lock by forcing an elongated member (such as a piece of tubing) into engagement with the protruding portion, the protruding portion is driven back into the forward portion, so that the tubing cannot become engaged therewith.

Abstract: An axial tumbler lock comprises a casing and a lock cylinder mounted in a lock body and forming a shear plane. A plurality of axial tumblers normally block notation of the casing relative to the cylinder. When a key is inserted, key posts urge the tumblers into an aligned position permitting rotation of the casing and opening of the lock. The tumblers are disposed in a nonregular pattern and a plurality of dummy pins are provided indistinguishable from the tumblers making detection of the tumblers and unauthorized operation of the lock extremely difficult.

Abstract: A flat key comprises a blank cut on a copying machine to form a shank, having a shank head. An intermediate head is formed with a slot, in which the shank head is received. A key head is detachably connected with the intermediate head, with wedge action between these latter heads.

Abstract: A key locating attachment for controlling the depth of penetration of a key into a lock. This attachment is engaged with the key and a portion thereof engages the face of the lock when the key is placed therein to align the complemental parts of the key and the lock to actuate the same. The attachment is adjustably fixed to the key in order to permit adjustment thereof to compensate for wear on the bearing surfaces of the lock and key which would otherwise cause misalignment of the interengaging parts of the key and the lock.