WO2000057006A1

WO2000057006A1 - Key blank with resiliently protruding pins

Info

Publication number: WO2000057006A1
Application number: PCT/IL2000/000164
Authority: WO
Inventors: Yoav Wienberger
Original assignee: HAMAFTEAH HAMISTOVEV Ltd
Current assignee: HAMAFTEAH HAMISTOVEV Ltd
Priority date: 1999-03-22
Filing date: 2000-03-16
Publication date: 2000-09-28
Anticipated expiration: 2001-09-22
Also published as: AU3320400A; IL129097A

Abstract

A key blank (10) comprising a body (12) and a head (11) connected to the body, the body designated to include key combination elements (14) so as to facilitate the operation of a lock when inserted in a keyway of the lock. At least one resiliently protruding pin element (16) is provided on said body (12), mounted inside a cavity (24), said resiliently protruding pin element (16) partially protruding from the cavity (24) when no external force is exerted on it, and retracts inwardly into the cavity, when a predetermined force is exerted on it, whereby the resiliently protruding pin (16) may actuate internal mechanism provided within the lock.

Description

KEY BLANK WITH RESILIENTLY PROTRUDING PINS

FIELD OF THE INVENTION

The present invention relates to keys and key blanks, more particularly it relates to a key blank with resiliently protruding pins.

BACKGROUND OF THE INVENTION

Many types of keys, key blanks and their associated locks are known in the art. Generally a key comprises an elongated shaft that has a combination portion. The combination portion provides varying elevations of the key surface, in a unique combination that matches corresponding pins in the lock, so that when the key is fully inserted inside the keyway the rotor in the lock cylinder may be turned to lock or unlock the lock. By providing different combinations of elevations key manufacturers are capable of supplying many different locks and matching keys that are uniquely associated and therefore not interchangeable, thus preventing opening a lock with a key that is not originally designed for the same lock.

In order to increase the number of combinations available for keys, the addition of a protrusion instead of a cut on the combination surface was suggested. This new concept adds another dimension to the combination surface of the key. By adding protrusions above the key level instead of the usual cuts that differ in height below the key level, the number of elevation combinations is significantly increased. An example is disclosed in US patent no. 4,377,082 titled "CYLINDER-LOCK WITH FLAT KEY" by Wolter filed in 1980. This 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.

Improved key blanks, keys and locks having additional pins on the combination surface are also available. En example for a key blank with movable pin shown in IL patent no. 104349 "LOCKING APPARATUS" disclosed by MUL-T-LOCK LTD. in 1993. This patent provides a key blank that includes a generally elongated shaft portion defining a key combination surface adapted to have formed thereon key cuts which define a key combination, the key blank including a movable pin element retained within the elongated shaft portion, the movable pin element being displaceable in a single direction, outwardly from the key combination surface.

The disadvantage of these types of key blanks is in the necessity to modify the lock's cylinder by grafting another resiliently protruding pin beside the set of the cotter pins provided in the stator of the lock's cylinder. This additional pin has a strong spring that pushes the movable pin in the key blank so that the opposite cotter pin is pushed, enabling the lock to open up. Grafting a resiliently protruding pin in the lock's cylinder is a relatively complicated task and the elimination of the need to modify the lock is strongly desired. The existence of the additional cotter pin, which interacts with the floating pin in the lock's cylinder is detrimental to the safety of the lock. A simple visual examination of the keyway enables burglars to learn of the location of the cotter pin, which sticks into the keyway, and helps them crack the lock. BRIEF DESCRIPTION OF THE INVENTION

It is an object of the present invention to provide a key blank with resiliently protruding pins that provide a wider range of elevation combinations in the key combination surface.

It is another object of the present invention to provide a key blank with resiliently protruding pins that incorporates the action of the resiliently protruding pin in the lock's cylinder and the action of a movable floating pin, eliminating the need to graft an additional resiliently protruding pin in the lock's cylinder.

It is yet another object of the present invention to provide a key blank with resiliently protruding pins that make it harder for burglars to crack the lock when using burglary tools such as picking tools for impression. There is thus provided, in accordance with a preferred embodiment of the present invention, a key blank comprising: a body and a head connected to said body, the body designated to include key combination elements so as to facilitate the operation of a lock when inserted in a keyway of the lock; at least one resiliently protruding pin element provided on said body, mounted inside a cavity, said resiliently protruding pin element partially protruding from the cavity when no external force is exerted on it, and retracts inwardly into the cavity, when a predetermined force is exerted on it; whereby the resiliently protruding pin may actuate internal mechanism provided within the lock.

Furthermore in accordance with yet another preferred embodiment of the present invention, there is provided a key blank comprising: a body and a head connected to said body, the body having at least one external surface designated to include key combination elements so as to facilitate the operation of a lock when inserted in a keyway of the lock; at least one resiliently protruding pin element provided on said at least one external surface, mounted inside a cavity, said resiliently protruding pin element partially protruding from the cavity when no external force is exerted on it, and retracts inwardly into the cavity, when a predetermined force is exerted on it; whereby the resiliently protruding pin may actuate internal mechanism provided within the lock.

Furthermore in accordance with yet another preferred embodiment of the present invention, said body is an elongated shaft having two opposite surfaces joined by edge surfaces, at least one of the two opposite surfaces defining a first key combination surface; and at least one of the resiliently protruding pin elements provided on said first combination surface

Furthermore in accordance with yet another preferred embodiment of the present invention, on each of the two opposite surfaces there is located at least one resiliently protruding pin element.

Furthermore in accordance with yet another preferred embodiment of the present invention, at least one of said resiliently protruding pin element is provided on at least one of said edge surfaces.

Furthermore in accordance with yet another preferred embodiment of the present invention, at least one longitudinal groove in the direction of the elongated axis of the shaft is engraved on said first key combination surface.

Furthermore in accordance with yet another preferred embodiment of the present invention, two grooves are engraved on said first key combination surface. Furthermore in accordance with yet another preferred embodiment of the present invention, said cavity is provided with an annular shoulder on which a rim that is provided on the bottom of the resiliently protruding pin element may rest, preventing the pin from ejecting out of the cavity.

Furthermore in accordance with yet another preferred embodiment of the present invention, a spring element is provided below the resiliently protruding pin element. Furthermore in accordance with yet another preferred embodiment of the present invention, at least one internal cavity is provided on the side of the pin facing the spring element allowing a portion of the spring to be parked inside.

Furthermore in accordance with yet another preferred embodiment of the present invention, two internal cavities are provided on the side of the pin facing the bottom of said cavity, and two springs provided below the pin so as to allow a portion of the springs to be parked inside the cavities.

Furthermore in accordance with yet another preferred embodiment of the present invention, an elastic block is provided below the pin. Furthermore in accordance with yet another preferred embodiment of the present invention, said elastic block is made from a material selected from the group of materials such as rubber or plastic.

Furthermore in accordance with yet another preferred embodiment of the present invention, said resiliently protruding pin element has a circular lateral cross-section.

Furthermore in accordance with yet another preferred embodiment of the present invention, said resiliently protruding pin element has a rectangular lateral cross-section.

Furthermore in accordance with yet another preferred embodiment of the present invention, said resiliently protruding pin element has a square lateral cross-section.

Furthermore in accordance with yet another preferred embodiment of the present invention, the portion of the resiliently protruding pin that protrudes from said cavity is provided with a circumferential inclination. Furthermore in accordance with yet another preferred embodiment of the present invention, the portion of the resiliently protruding pin that protrudes from said cavity is provided with inclinations on the sides of the pin that face the direction in which said body is inserted into a keyway.

Furthermore in accordance with yet another preferred embodiment of the present invention, the surface of the protruded portion of the resiliently protruding pin is provided with a conic protrusion. Furthermore in accordance with yet another preferred embodiment of the present invention, the surface of the protruded portion of the resiliently protruding pin is provided with a conic recess.

Furthermore in accordance with yet another preferred embodiment of the present invention, the surface of the protruded portion of the resiliently protruding pin is substantially semispherical.

Furthermore in accordance with yet another preferred embodiment of the present invention, a resilient bar is attached at one end to the pin, and at the other end to said body, said resilient bar is given free space in the form of a slot in the body to move inwardly as to allow insertion of the pin into said cavity.

Furthermore in accordance with yet another preferred embodiment of the present invention, the resiliently protruding pin is a flat resilient platform attached at the edges of said cavity and covers the cavity. Furthermore in accordance with yet another preferred embodiment of the present invention, the cavity and the platform are both elongated in the direction in which said key blank is inserted into or removed from a keyway.

Furthermore in accordance with yet another preferred embodiment of the present invention, the resiliently protruding pin is made from an elastic material selected from the group of materials such as rubber or plastic.

Furthermore in accordance with yet another preferred embodiment of the present invention, the resiliently protruding pin is attached to the bottom of said cavity.

Furthermore in accordance with yet another preferred embodiment of the present invention, said body is elongated.

Furthermore in accordance with yet another preferred embodiment of the present invention, said body has a rectangular lateral cross-section.

Furthermore in accordance with yet another preferred embodiment of the present invention, said body has a circular lateral cross-section. Furthermore in accordance with yet another preferred embodiment of the present invention, the key blank is provided with key combination elements so as to facilitate the operation of the lock.

BRIEF DESCRIPTION OF THE FIGURES

In order to better understand the present invention, and appreciate its practical applications, the following Figures are provided and referenced hereafter. It should be noted that the Figures are given as examples only and in no way limit the scope of the invention as defined in the appending Claims.

Like components are denoted by like reference numerals.

Figure 1 illustrates an isometric view of a key with resiliently protruding pins in accordance with a preferred embodiment of the present invention. Figure 2A illustrates a side cross sectional view of a key shaft with a resiliently protruding pin in accordance with a preferred embodiment of the present invention. Figure 2B illustrates a side cross sectional view of a key shaft with a resiliently protruding pin in accordance with another preferred embodiment of the present invention. Figure 2C illustrates a side cross sectional view of another preferred embodiment of a resiliently protruding pin engaged in the key shaft shown in Figure 2B.

Figure 2D illustrates a side cross sectional view of yet another preferred embodiment of a resiliently protruding pin engaged in the key shaft shown in Figure 2B.

Figure 2E illustrates a side cross sectional view of yet another preferred embodiment of a resiliently protruding pin engaged in the key shaft shown in Figure 2B. Figure 2F illustrates a side cross sectional view of yet another preferred embodiment of a resiliently protruding pin engaged in the key shaft shown in Figure 2B, resting on two springs. Figure 3 illustrates a lateral cross sectional view of the key shaft showed in Figure 2A. The cross section is in the center of the floating pins.

Figure 4A illustrates a side cross sectional view of a lock's cylinder that matched a key such as the one illustrated in Figure 1 . Figure 4B illustrates a side cross sectional view of a lock's cylinder with a corresponding key such as the key illustrated in Figure 1 fully inserted inside the keyway.

Figure 4C illustrates a side cross sectional view of a lock's cylinder with a corresponding key having a different combination from the combination of the lock shown in Figure 4B, fully inserted inside the keyway. Figure 5A illustrates a side cross sectional view of a key shaft with a resiliently protruding pin in accordance with yet another preferred embodiment of the present invention. Figure 5B illustrates an elevated view of a key shaft in accordance with the embodiment shown in Figure 5A. Figure 6A illustrates a side cross sectional view of a key shaft with a resiliently protruding pin in accordance with yet another preferred embodiment of the present invention. Figure 6B illustrates an elevated view of a key shaft in accordance with the embodiment shown in Figure 6A. Figure 7 illustrates a side cross sectional view of a key shaft in accordance with yet another preferred embodiment of the present invention. Figure 8 illustrates a side cross sectional view of a key shaft with a resiliently protruding pin in accordance with yet another preferred embodiment of the present invention. Figure 9A illustrates a side cross sectional view of a key shaft with a resiliently protruding pin in accordance with yet another preferred embodiment of the present invention. Figure 9B illustrates an elevated view of a key shaft in accordance with the embodiment shown in Figure 9A.

Figure 10 illustrates a side cross sectional view of a key shaft with a resiliently protruding pin in accordance with yet another preferred embodiment of the present invention. The cavity in the shaft is provided with a seal. Figure 1 1 illustrates an isometric view of a key with several resiliently protruding pins in accordance with yet another preferred embodiment of the present invention. Figure 12A illustrates a lateral cross sectional view of a key shaft having a rectangular cross section with several resiliently protruding pins in accordance with yet another preferred embodiment of the present invention. Figure 12B illustrates a lateral cross sectional view of a key shaft having a circular cross section with several resiliently protruding pins in accordance with yet another preferred embodiment of the present invention.

DETAILED DESCRIPTION OF THE PRESENT INVENTION AND FIGURES

In general, the key or key blank of the present invention comprises a body which carries on it the combination surface for the operation of a corresponding lock, and a head attached to it to be held by the user. Commonly a key or key blank would comprise an elongated shaft and a key- head, although the body may possess different shapes or cross-sections, such as a cylindrical body, spherical or semispherical body, etc. The shaft has at least one combination surface, on which a resiliently protruding pin is positioned. It is possible to place more than one resiliently protruding pin on each combination surface of the shaft. It is also possible to provide the key blank with two identical opposite surfaces bearing the combination elements. The objective of the identical opposite surfaces on the key shaft is to allow the insertion of the key to the keyway with either one of the surfaces up.

Reference is now made to Figure 1 illustrating an isometric view of a key with resiliently protruding pins in accordance with a preferred embodiment of the present invention. Key 10 comprises a key-head 11 , from which an elongated shaft 12 is extended. A portion of shaft 12 designed to be inserted into the keyway of the lock has two grooves 13 engraved on one surface 15 of the shaft, on which the cuts defining a part of the key combination are carved in. Grooves 13 on the shaft's surface match the lock's rotor internal surfaces defining the keyway of a certain corresponding lock. A row of cuts 14 having different elevations are carved in the grooved portion of the shaft. Aligned to cuts 14, a resiliently protruding pin 16 is positioned. Cuts 14 and resiliently protruding pin 16 define the complete combination of the key. It should be mentioned that the opposite surface of shaft 12 (not shown in the figure) is identical to surface 12 with its features. It is noted that the present invention is not limited to key blanks having two longitudinal grooves, as any number of grooves may be provided, or no grooves at all. In fact the key blank may have any shape or profile, and still fall within the scope of the present invention.

Reference is now made to Figure 2A that illustrates a side cross sectional view of a key shaft with a resiliently protruding pin in accordance with a preferred embodiment of the present invention. A shaft 20 having two opposite key combination surfaces 21 and 22, joined by edge surfaces 17 is shown. Each surface is designed to bear the cuts and the resiliently protruding pin defining the key combination. A pin 23 is placed in a cavity 24 provided in shaft 20. The cavity is provided with annular shoulder 25 on which a rim 26 that is provided on the bottom of pin 23 may rest, preventing pin 23 from ejecting out of the cavity. Below pin 23, a spring element 28 is provided, confined in cavity 24 between the bottom of the cavity and pin 23. Upon inserting shaft 20 to the matching keyway (of a lock), pin 23 sinks into cavity 24 while depressing spring element 28. Withdrawal of shaft 20 from the keyway releases the spring while causing pin 23 to go back to a protruded position.

The portion of pin 23 that protrudes from cavity 24 is provided with a circumferential inclination 27 that enables a smooth entry of shaft 20 to the lock's keyway. The key is inserted into or removed from the keyway while surfaces 21 and 22 slide parallel and adjacent to the internal surfaces of the lock's rotor, which defines the keyway of the lock. Upon inserting the key into the keyway, pin 23 that protrudes above the level of surface 21 collides into the perpendicular external surface of the lock's rotor. Circumference inclination 27 allows a smooth insertion of shaft 20 through the rotor's external surface, and as a consequence, pin 23 sinks into cavity 24. In order to understand better how a key with resiliently protruding pins in accordance with the present invention cooperates with a matching lock's cylinder, reference is now made to Figure 4A illustrating a side cross sectional view of a lock's cylinder that matches a key such as the one illustrated in Figure 1. A lock's cylinder 30 comprises a rotor 32 and a stator 31. Rotor 32 is adapted to rotate about its longitudinal axis and activate a mechanism that eventually opens up the lock. The internal surfaces of rotor 32 define the keyway 33. Stator 31 encloses rotor 32 and accommodates cotter pins that match the key combination of a specific key. Two cotter pins 34 and 35 that correspond to cuts on the combination surface, and an additional cotter pin 36 that corresponds to the resiliently protruding pin, are positioned in bores 43 provided inside the lock's body extending from stator 31 into rotor 32, substantially perpendicular to the keyway, and pushed towards keyway 33 by springs 37 placed underneath them. Each cotter pin is made from two pieces of different lengths. In order to allow the rotor to rotate, the cotter pins have to move and reposition perpendicularly to the longitudinal axis of rotor 32 so that the contact point 38 between the two pieces of each cotter pin levels with the contact surface between the rotor and the stator. In the situation shown in Figure 4A, rotor 32 can not rotate since the cotter pins do not allow relative movement between the rotor and the stator. The position in which contact points 38 level with the contact surface between the rotor and the stator can be achieved only by fully inserting a matching key into the keyway.

Reference is now made to Figure 4B illustrating a side cross sectional view of a lock's cylinder and a corresponding key such as the key illustrated in Figure 1 , fully inserted in the keyway. When a key 39 is fully inserted in keyway 33 of cylinder 30, cuts 40 and resiliently protruding pin 41 defining the key combination, are positioned opposite the corresponding cotter pins 34, 35 and 36 in the lock's stator. A portion of cotter pins 34 and 35 spring into the corresponding cuts 40 as a result of the force of springs 37 underneath them. The depth of cuts 40 in the matching key is predetermined so that the distance that contact points 38 between the two pieces of the cotter pins travel is exactly the distance that is needed for contact points 38 to move to the contact surface between rotor 32 and stator 31. On the other hand, when resiliently protruding pin 41 is positioned opposite the corresponding cotter pin 36 in the stator, resiliently protruding pin 41 is free to spring out of its cavity, pushing cotter pin 36 backwards, and realigning contact point 38 with the contact surface between the stator and the rotor. The force (i.e. the spring coefficient) of spring element 42 has to be greater than the force of spring 37 so as facilitate pushing of cotter pin 36 backwards. Cotter pin 36 is designed to move in the opposite direction of cotter pins 34 and 35 while contact point 38 moves and levels also with the contact surface between the rotor and the stator. Leveling all contact points 38 with the contact surface between rotor 32 and stator 31 is a necessary condition for the rotation of the rotor. Only in the situation shown in Figure 4B, rotor 32 can rotate as the bottom parts of cotter pins 34, 35 and 36 stay in the stator while the upper parts of the cotter pins rotate with rotor 32 and the key. The rotation of the rotor activates a mechanism that eventually opens up or closes (depending on the direction of rotation) the lock. In the embodiment of the key with a resiliently protruding pin shown in Figure 1 , resiliently protruding pin 16 is aligned with cuts 14. This type of keys matches a lock that resembles the lock shown in Figure 4A. Resiliently protruding pin 41 may by positioned in any combination between cuts 40 as shown in Figure 4C illustrating a side cross sectional view of a lock's cylinder with a corresponding key having a different combination, fully inserted inside the keyway. One or more resiliently protruding pins may be combined between the cuts as long as they are aligned with the cuts the still be covered by the scope of the present invention. Both surfaces (21 , 22) of the shaft have identical key combination surfaces so as to allow insertion of the key with either surface up. This means that the combination surface on either side is identical. Hence, a resiliently protruding pin is located on each surface as shown in Figure 3, illustrating a lateral cross sectional view of the key blank shown in Figure 2A. Pin 23 is located in cavity 24 on surface 21 of shaft 20, with spring element 28 positioned beneath it. An identical resiliently protruding pin 45 is located in corresponding cavity 46 on the opposite surface 22, with spring element 47.

The resiliently protruding pin may have different cross sections. Reference is made to Figure 2B that illustrates a side cross sectional view of a key shaft with a resiliently protruding pin in accordance with another preferred embodiment of the present invention. Key shaft 50 has a similar structure as the shaft in Figure 2A. Shaft 20 has a cavity 24 in surface 21. The edge of cavity 24 is provided with an annular shoulder 25 on which a rim 55 that is provided on the bottom of pin 51 may rest, preventing pin 51 from ejecting out of the cavity.

On the portion of pin 51 that protrudes above the level of surface 21 , a circumferential inclination 53 is provided adapted to facilitate a smooth insertion of shaft 20 to the keyway as explained earlier.

An internal cavity 52 is provided on the side of the pin facing the spring element allowing a portion of the spring to be parked inside. This allows spring 54 to be longer with respect to spring 28 in Figure 2A. Since the force of the resiliently protruding pin's spring should be greater than the force of the lock's cotter pin spring, the additional spring length provided by using a cavity in the pin adds more strength to the resiliently protruding pin without the need to change the type of spring used (i.e. greater spring coefficient). In an optional embodiment it is possible to provide the resiliently protruding pin with two springs in order to increase the force that pushes the pin towards the cotter pin. Reference is now made to Figure 2F illustrating a side cross sectional view of yet another preferred embodiment of a resiliently protruding pin engaged in the key shaft shown in Figure 2B, resting on two springs. A pin 56 is provided with two internal cavities 57, in which two springs 58 are accommodated.

In order to increase the number of combinations available by the combination surface of the key, different structures of resiliently protruding pins may be provided. Reference is now made to Figures 2C, 2D and 2E that illustrate side cross sectional views of other preferred embodiments of resiliently protruding pins engaged in a key blank. The changes in the structure of the resiliently protruding pin are made at the protruded portion of the resiliently protruding pin. Figure 2C illustrates a resiliently protruding pin 60 resting on a spring element 61. The surface of the protruded portion of resiliently protruding pin 60 may be preferably modified by an addition of a conic protrusion 62. On the other hand, it is possible to carve a recess into the protruded surface. Figure 2D illustrates a preferable resiliently protruding pin 65 resting on a spring element 66 having a conic recess 67. This is applicable in cases where the cotter pins themselves have additional internal shaft that may relocate within the outer shaft. Figure 2E illustrates a resiliently protruding pin 68 having a semispherical top 69. Semispherical top 69 facilitates also the smooth insertion of the key into the lock's keyway and acts similarly to the circumferential inclinations in the above mentioned types of pins. Other structures of a resiliently protruding pin may be provided in order to increase the number of combinations available by the combination surface of the key blank. It is noted that any other structures of a resiliently protruding pin would be covered by the scope of the present invention.

Resiliency can be rendered to the resiliently protruding pin also by other mechanisms that do not involve a spring element beneath the pin. Reference is now made to Figure 5A that illustrates a side cross sectional view of a key shaft with a resiliently protruding pin in accordance with yet another preferred embodiment of the present invention. A key shaft 70 having two surfaces 71 and 72 is provided with a cavity 73. A resilient bar 75 is attached at one end to pin 76 (inserted in bore 77), and at the other end to shaft 70, and given free space, in the form of slot 74 in shaft 70, to move inwardly as to allow insertion of pin 76 into cavity 73, while pressing the resilient bar down.

Slot 74 can also be seen in Figure 5B that illustrates an upper view of a key shaft in accordance with the embodiment shown in Figure 5A. The attachment can be performed by nailing, squeezing or tightening the end of bar 75 to the bottom surface of slot 74 provided the upper surface of the bar is aligned with surface 71. The alignment of the bar 75 and surface 71 is necessary so that the key can be smoothly inserted in the keyway.

Pin 76 is held only by bar 75. When the key is not inserted in a keyway, pin 76 protrudes above the level of surface 71. When the key is inserted into the keyway and pin 76 is pressed into cavity 73, the bar's resiliency allows it to bend inwardly. The bar's resiliency also causes the pin to spring back into its original position (protruding position) when the key is fully inserted in the keyway and the pin is opposite a cotter pin in the lock. As mentioned earlier, the condition for the ability of the resiliently protruding pin to push the cotter pin in the stator is that the force of the bar is greater than the force of the cotter pin's spring. Upon withdrawal of the key out from the keyway, the pin sinks again into cavity 73 when it encounters the internal surface of the keyway, and protrudes again upon a full withdrawal of the key. Pin 76 is provided with a circumferential inclination 77 on the upper edge of the pin so that a smooth insertion and withdrawal of the key to and from the keyway can be performed.

In accordance with yet another preferred embodiment of the present invention, a flat type of resiliently protruding pin is provided. Reference is now made to Figures 6A and 6B illustrating a side cross sectional view and an upper view of a key shaft with a resiliently protruding pin. Surface 84 of a key's shaft 80 is provided with an elongated and inclined cavity 81 having a flat surface 82 at the bottom of the cavity. Cavity 81 is elongated in the direction of the shaft's longitudinal axis, as clearly shown in Figure 6B. A flat resilient platform 83 is attached at both sides to the edged of cavity 81 by nailing, squeezing or tightening, so that platform 83 covers cavity 81. Platform 83 protrudes above the level of surface 84 and has inclinations 85 on both sides of the platform. When the key is inserted into a keyway, the protruding portion of platform 83 is resiliently pressed into cavity 81 that has a similar yet opposite profile. When the key is withdrawn from the keyway, the platform springs back into its protruded position. Again, inclinations 85 facilitate a smooth insertion and withdrawal of the key into and out from the lock's keyway. Another type of resiliently protruding pin is provided in yet another embodiment of the present invention. Reference is made to Figure 7, illustrating a side cross sectional view of a key shaft in accordance with yet another preferred embodiment of the present invention. The shaft 90 and the cavity 91 correspondingly resemble shaft 20 and cavity 24 in the preferred embodiment shown in Figure 2A. Pin 92 is provided with a rim 93 at the bottom portion and the edge of cavity 91 is also provided with an annular shoulder 94, so that the pin that is placed in cavity 91 can not eject out of the cavity. The profile of the pin's top surface is inclined for the same reasons as explained earlier. Resiliently protruding pin 92 rests on an elastic block 95 made from a rubbery or plastic material that may be pressed inwardly and recover when released. When only the weight of the pin itself rests on block 95 pin 92 protrudes above the level of surface 96 of shaft 90. When an additional force is applied on pin 92 the pin is pressed inwardly towards the bottom of cavity 91 , causing block 95 to squeeze. This happens whenever the key is inserted in the keyway. It should be mentioned again that the resilient force of block 95 must be greater than the force of the corresponding cotter pin's spring in the lock's stator.

In yet another preferred embodiment of the present invention, the pin and the resilient element is made as one unit. Reference is now made to Figure 8 that illustrates a side cross sectional view of a key shaft with a resiliently protruding pin in accordance with yet another preferred embodiment of the present invention.

Shaft 100 is provided with a cavity 101. A pin 102 made of a resilient and elastic material such as rubber or plastic is attached to the bottom of cavity 101. The attachment of the bottom part of pin 102 to cavity 101 may be intensified by using strengtheners 103. The upper part of pin 102 protrudes above the level of surface 104. Pin 102 is provided with a circumferencial inclination 105 that enables smooth insertion of the key with the resiliently protruding pin to a keyway. When force is applied on pin 102 perpendicularly to the shaft's longitudinal axis and towards the bottom of cavity 101 , the pin squeezes inwardly and the upper surface 106 of the pin is aligned with surface 104. This happens when the key is inserted into the keyway and the internal surface of the keyway exerts force on the pin in a direction perpendicular to the shaft's axis. When the key is fully inserted and the pin is positioned opposite the corresponding cotter pin, the resiliently protruding pin protrudes from its cavity while pushing the cotter pin and its corresponding spring backwards.

Withdrawal of the key from the forces the pin to squeeze back into cavity 101 due to the force exerted by the internal surface of the keyway. When the key is fully withdrawn, the resiliently protruding pin is free to bulge again and protrudes above the level of surface 104. Reference is now made to Figures 9A and 9B illustrating a side cross sectional view and an elevated view, respectively, of a key shaft with a resiliently protruding pin in accordance with yet another preferred embodiment of the present invention. A resiliently protruding pin 110 protrudes from a cavity 111 in a key shaft 112. Resiliently protruding pin 110 rests on a spring 113 that pushes resiliently protruding pin 110 outwardly from cavity 111. Pin

110 is provided with a rim 114 at the bottom portion and the edge of cavity

111 is also provided with a shoulder 115, so that the pin that is placed in cavity 111 can not eject out of the cavity. The lateral square shape of the pin 110 is shown in the elevated view in Figure 9B. The top of pin 110 is provided with inclinations 116 on four sides of the square, from the same reasons that were mentioned earlier.

It is possible to provide the top of a resiliently protruding pin, which is square or rectangular, with only two opposite inclinations on both sides of the pin, facing the direction in which the key is inserted into or withdrawn from the keyway.

It may be preferable, from manufacturers point of view, to drill a bore through the entire body of the key, instead of providing a cavity for the accommodation of the pin, in which case a sealing plate would be required to close the bore on one side. Reference is now made to Figure 10 illustrating a side cross sectional view of a key shaft with a resiliently protruding pin in accordance with yet another preferred embodiment of the present invention. A bore 121 is provided in a key's shaft 120. Bore 121 is than closed with a sealing plate 122 that is aligned with surface 123 of the shaft, so as to present a substantially uniform surface. A resiliently protruding pin 124 that rests on spring 125 is accommodated in bore 121. The resiliently protruding pin may be any resiliently protruding pin, such as the ones described earlier, or others.

Resiliently protruding pins are not necessarily located on the combination surface or aligned with the cuts, if there are any cuts. Reference is now made to Figure 11 illustrating an isometric view of a key with several resiliently protruding pins in accordance with yet another preferred embodiment of the present invention Key 10 comprises a key-head 11 , from which an elongated shaft 12 is extended A portion of shaft 12 designed to be inserted into the keyway of a lock has two grooves 13 engraved on one surface 15 of the shaft, on which the cuts defining a part of the key combination are carved in A row of cuts 14 having different elevations are carved in the grooved portion of the shaft Surface 15 of shaft 12 is provided with a rectangular resiliently protruding pin 130 The edge surface 131 that joins surfaces 15 and 16 is further provided with a resiliently protruding pin 132 Cuts 14 and resiliently protruding pins 130 and 131 define the complete combination surface of the key It should be noted that pins 130 and 131 are both provided with inclinations 133 only on the sides of the pins that face the direction of insertion of shaft 12 in the keyway

When a key having resiliently protruding pins that are not aligned with the cuts is used, bores for cotter pins have to be grafted in the lock's cylinder opposite the anticipated location of the resiliently protruding pins when the key is fully inserted in the keyway

Adding resiliently protruding pins in unexpected locations on the key and using pins instead of cuts in general promote significantly the resistance of the lock against burglar attempts to crack it Locks having a combination based only on cuts are relatively easy to crack using picking tools used for impression, since the cotter pins have to be arranged in different heights within the keyway in order to unlock the key Instead, in order to crack a lock matching to a key having resiliently protruding pins, the cotter pins have to be arranged in specific heights inside the cylinder's bores that accommodate the cotter pins (i e out of the keyway) Forcing the cotter pins that match the resiliently protruding pins to be arranged in the specific height inside the bore in the cylinder is much more a difficult task

Reference is now made to Figure 12 illustrating a lateral cross sectional view of a key shaft having a rectangular cross section with several resiliently protruding pins in accordance with yet another preferred embodiment of the present invention The key's shaft 140 has a rectangular cross section and is provided with different types of resiliently protruding pins 141 , 142, 143 and 144, each pin is provided on each side of shaft 140. Again, the shape of the resiliently protruding pins may vary, presenting different cross-sections or shapes (see, for example, Figure 2A-2F). The matching lock that corresponds to the key shown in Figure 12A has to be provided with matching cotter pins on four sides of the keyway.

The key shaft may be a shaft having any cross-section as long as it matches the corresponding keyway. Reference is now made to Figure 12B illustrating a lateral cross sectional view of a key shaft having a circular cross section with several resiliently protruding pins in accordance with yet another preferred embodiment of the present invention. Shaft 150 has a circular cross- section and is provided with three resiliently protruding pins 151 on the shaft's circumference. It should be noted that the shaft of the key may be a body having any cross-section such as rectangular, square, triangular, circular etc. Any possible shape of the shaft's body is covered by the scope of the present invention.

The resiliently protruding pin of the present invention may be provided in a range of sizes. The pin may also be assigned other tasks, such as acting as an electrical circuit switch. It should be clear that the description of the embodiments and attached

Figures set forth in this specification serves only for a better understanding of the invention, without limiting its scope as covered by the following Claims.

It should also be clear that a person in the art, after reading the present specification could make adjustments or amendments to the attached Figures and above described embodiments that would still be covered by the following Claims.

Claims

C L A I M S

1. A key blank comprising: a body and a head connected to said body, the body designated to include key combination elements so as to facilitate the operation of a lock when inserted in a keyway of the lock; at least one resiliently protruding pin element provided on said body, mounted inside a cavity, said resiliently protruding pin element partially protruding from the cavity when no external force is exerted on it, and retracts inwardly into the cavity, when a predetermined force is exerted on it; whereby the resiliently protruding pin may actuate internal mechanism provided within the lock.

2. A key blank comprising: a body and a head connected to said body, the body having at least one external surface designated to include key combination elements so as to facilitate the operation of a lock when inserted in a keyway of the lock; at least one resiliently protruding pin element provided on said at least one external surface, mounted inside a cavity, said resiliently protruding pin element partially protruding from the cavity when no external force is exerted on it, and retracts inwardly into the cavity, when a predetermined force is exerted on it; whereby the resiliently protruding pin may actuate internal mechanism provided within the lock.

3. The key blank according to Claim 2, wherein said body is an elongated shaft having two opposite surfaces joined by edge surfaces, at least one of the two opposite surfaces defining a first key combination surface; and at least one of the resiliently protruding pin elements provided on said first combination surface

4. The key blank according to Claim 3, wherein a on each of the two opposite surfaces there is located at least one resiliently protruding pin element.

5. The key blank according to Claim 3, wherein at least one resiliently protruding pin element is provided on at least one of said edge surfaces.

6. The key blank according to Claim 3, wherein at least one longitudinal groove in the direction of the elongated axis of the shaft is engraved on said first key combination surface.

7. The key blank according to Claim 5, wherein two grooves are engraved on said first key combination surface.

8. The key blank according to Claim 2, wherein said cavity is provided with an annular shoulder on which a rim that is provided on the bottom of the resiliently protruding pin element may rest, preventing the pin from ejecting out of the cavity.

9. The key blank according to Claim 2, wherein a spring element is provided below the resiliently protruding pin.

10. The key blank according to Claim 9, wherein at least one internal cavity is provided on the side of the pin facing the spring element allowing a portion of the spring to be parked inside.

11. The key blank according to Claim 9, wherein two internal cavities are provided on the side of the pin facing the bottom of said cavity, and two springs provided below the pin so as to allow a portion of the springs to be parked inside the cavities.

12. The key blank according to Claim 2, wherein an elastic block is provided below the pin.

13. The key blank according to Claim 12, wherein said elastic block is made from a material selected from the group of materials such as rubber or plastic.

14. The key blank according to Claim 2, wherein said resiliently protruding pin element has a circular lateral cross-section.

15. The key blank according to Claim 2, wherein said resiliently protruding pin element has a rectangular lateral cross-section.

16. The key blank according to Claim 2, wherein said resiliently protruding pin element has a square lateral cross-section.

17. The key blank according to Claims 14 or 15 or 16, wherein the portion of the resiliently protruding pin that protrudes from said cavity is provided with a circumferential inclination.

18. The key blank according to Claims 15 or 16, wherein the portion of the resiliently protruding pin that protrudes from said cavity is provided with inclinations on the sides of the pin that face the direction in which said body is inserted into or removed from a keyway.

19. The key blank according to Claim 2, wherein the surface of the protruded portion of the resiliently protruding pin is provided with a conic protrusion.

20. The key blank according to Claim 2, wherein the surface of the protruded portion of the resiliently protruding pin is provided with a conic recess.

21. The key blank according to Claim 2, wherein the surface of the protruded portion of the resiliently protruding pin is substantially semispherical.

22. The key blank according to Claim 2, wherein a resilient bar is attached at one end to the pin, and at the other end to said body, said resilient bar is given free space in the form of a slot in the body to move inwardly as to allow insertion of the pin into said cavity.

23. The key blank according to Claim 2, wherein the resiliently protruding pin is a flat resilient platform attached at the edges of said cavity and covers the cavity.

24. The key blank according to Claim 23, wherein the cavity and the platform are both elongated in the direction in which said key blank is inserted into or removed from a keyway.

25. The key blank according to Claim 2, wherein the resiliently protruding pin is made from an elastic material selected from the group of materials such as rubber or plastic.

26. The key blank according to Claim 25, wherein the resiliently protruding pin is attached to the bottom of said cavity.

27. The key blank according to Claim 2, wherein said body is elongated.

28. The key blank according to Claim 27, wherein said body has a rectangular lateral cross-section.

29. The key blank according to Claim 27, wherein said body has a circular lateral cross-section.

30. The key blank according to any one of Claims 1 to 29, wherein the key blank is provided with key combination elements so as to facilitate the operation of the lock.