CODED KEY SECURITY LOCK

Abstract

The invention relates to a lock (10) controllable with a key (12) having a bit (94). Said lock comprises: a cylinder (14) having a passage (92); a driver (22) comprising a central portion (50) opposite said passage (92) and a circular rim (54) having two opposing notches (72, 74), said bit (94) being adapted to be engaged in said passage (92) to mesh with said central portion (50); two wedges for engaging in said notches (74, 72) so as to lock said driver (22) from rotation. Said circular rim (54) having two slices (56, 58), said notches (74, 72) are formed in one (56) of said slices, while the other (58) has a notch (84); and one of said keys (32) is equipped with a lateral lug (44) capable of engaging in said notch (84).

Description

[0001] The present invention relates to a security lock adapted to be operated with a key having a coded bit.

[0002] One area of ​​application envisaged is, in particular, but not exclusively, that of padlocks.

[0003] Known security locks include a cylinder made of coded washers applied successively against each other to form a keyway leading to the two opposite ends of the cylinder. They also include a driver installed at one end of the cylinder. The driver has a central portion projecting axially that extends along the keyway. It also has a circular rim with two notches designed to act as stops. The central portion of the driver is slotted to receive the key's bit when it is inserted into the keyway. The bit then rotates into contact with the central portion of the driver.

[0004] Furthermore, the security lock includes two eccentric keys mounted pivotally on the end of the cylinder, to which the driver is aligned. These keys are connected to rods that extend along the cylinder and are fitted with extended returns in the keyway. The keys pivot freely in a plane substantially perpendicular to the cylinder axis. Thus, the ends of the keys engage against the support stops when they extend into the notches of the circular rim, thereby preventing the driver from rotating.When the cam, which is rotationally fixed to the driver, is allowed to rotate inside the cylinder of coded washers, it causes, in sequence, first the separation of the keys which release the notches, thanks to the cooperation of the cam with the return of the rods, then the rotation of the driver which acts for example on the locking mechanism of a padlock.

[0005] To enhance the security of this type of lock, it was devised to differentiate the keys and create a crenellated notch. One of the keys has a free end that forms a claw, allowing it to engage in the crenellated notch. The other key then acts as a lever against the stop of the other notch. Furthermore, both keys pivot simultaneously in opposite directions. This makes picking the lock more difficult, as the mechanism is blocked in both directions of rotation. Reference can be made to document FR 2 757 557, which describes this type of security lock.

[0006] Nevertheless, picking such a lock is possible and, moreover, the number of parts required for its implementation is significant and increases the manufacturing cost.

[0007] Also, a problem that arises and that the present invention aims to solve is to provide a tamper-proof security lock that can be produced at an advantageous cost.

[0008] For this purpose, a security lock is proposed that can be ordered with a key having a coded bit.The said security lock comprises: a cylinder of coded washers having two opposite ends and a passageway opening into said two ends; a driver mounted for rotation at one of said two ends, said driver comprising a central part extending opposite said passageway and a circular border having two opposite notches, said cam being adapted to be engaged in said passageway through the other of said ends to engage with said central part; and, two eccentric keys mounted for pivoting on said one of said ends of said cylinder to engage respectively in said notches so as to block said driver from rotating, said cam being adapted to cause sequentially, the separation of said keys to release said notches, and the rotation of said driver.The said circular border having two axially offset slice portions, the said notches are made in one of the said slice portions, while the other of the said slice portions also has a notch opening into one of the said notches; and one of the said keys is equipped with a lateral lug capable of engaging in the said notch when the key extends into the said one of the said notches.

[0009] Thus, a feature of the invention lies in the implementation of a notch in the other portion of the circular edge of the driver, the notch opening laterally into the corresponding notch, and a lateral stud on one of said keys such that the lateral stud engages in the notch when the key extends into the corresponding notch. In this way, the free end of the key abuts against the support stop formed by the notch when the driver tends to rotate in one direction, the key then acting as a support, while the stud bears against one of the sides of the notch when the driver tends to rotate in the opposite direction.Therefore, when the keys engage in the notches, the driver is locked in rotation in both directions and offers no possibility of rotational play that could facilitate picking.

[0010] Preferably, the other of said slice portions further has another notch opening into the other of said notches, and the other of said keys is equipped with another lateral lug capable of engaging in said other notch when said other of said keys extends into said other of said notches. In other words, said circular rim having two axially offset slice portions, said notches are formed in one of said slice portions, while the other of said slice portions further has two notches opening respectively into said notches, and said keys are respectively equipped with a lateral lug capable of engaging in said notches when the keys extend into said notches. Thus, each of the keys is equipped with a nipple while another portion of the edge has two notches intended to receive the nipples respectively.In this way, each of the keys allows the driver to be locked in both directions of rotation. Picking the lock that is the subject of the invention is thus made even more difficult. Moreover, and advantageously, the keys are identical and are installed diametrically opposite the end of the cylinder. They are therefore able to pivot in opposite directions of rotation in order to release the driver or engage with it. Also, thanks to the use of identical keys, the number of different parts required to assemble the security lock that is the subject of the invention is reduced.

[0011] According to a particularly advantageous embodiment of the invention, said notches extend substantially in a V-shape, each forming a support stop. The V-shaped notches have a first flank extending substantially along a fraction of a radius and a second flank substantially perpendicular to it. The first flank then forms the support stop. Preferably, the two V-shaped notches are antisymmetric with respect to an axial plane of the drive, as will be explained in more detail later in the description.

[0012] Furthermore, according to a particularly advantageous implementation feature, each of the keys has a free end adapted to bear against the support stops. The free end of the keys is preferably rounded so as to cooperate with the rounded bottom of the V-shaped notches.

[0013] Furthermore, the notch extends preferentially along an average direction away from the center of the circular rim, forming a hook-shaped flank. In other words, the average direction of the notch is inclined relative to a radius of the driver that intersects the notch. Thus, as will be explained in more detail later in the description, one of the flanks of the notch forms a hook into which the pin engages. Therefore, under certain circumstances, which will be detailed, the key is prevented from pivoting. Advantageously, the hook-shaped flank is opposite the corresponding stop. Thus, when the driver is forced to rotate in one direction, the pin engages with the hook-shaped flank, and the corresponding key is prevented from pivoting.When the driver is forced to rotate in the opposite direction, the free end of the key comes to rest against the support stop, preventing further rotation. As will be explained below, the hook-shaped flank has a double curvature to accentuate the hook shape.

[0014] Advantageously, the keys are mounted on two actuated rods extending along the cylinder in diametrically opposed positions. The keys are rotationally fixed to the two actuated rods. Each rod has a return that extends through coded washers, allowing the key's cam to engage with these returns and pivot the keys via the rods.

[0015] Preferably, the said driver has a crankpin oriented opposite to the said cylinder. The crankpin is then adapted to cooperate with a moving element in translation, for example a bolt, precisely to drive it in translation as will be explained below.

[0016] According to another object, and in accordance with a first embodiment, the present invention relates to a security key box comprising a parallelepiped-shaped case and a hinged door for closing said case, the key box comprising a security lock as described above and said driver is equipped with a cam for locking said hinged door on said parallelepiped-shaped case.

[0017] According to yet another object and in accordance with a second embodiment, the present invention relates to a security padlock comprising: a T-shaped housing having a cylindrical recess surmounted by a transverse recess having two opposite ends; a shackle pivotally mounted on one of said ends of said transverse recess, said shackle having a free hook end adapted to extend into the other end of said transverse recess; and a longitudinal bolt slidably mounted inside said transverse recess to engage with said free hook end in said other end. The security padlock includes a safety lock as described above, said safety lock being installed inside said cylindrical recess so that said driver cooperates with said longitudinal bolt.

[0018] Other features and advantages of the invention will become apparent from the following description of particular embodiments of the invention, given by way of example but not limitation, with reference to the attached drawings in which: there Figure 1 is a schematic perspective view of a security lock according to the invention; the Figure 2 is a schematic perspective view of an element of the lock illustrated on the Figure 1 ; there Figure 3 is a schematic perspective view of other elements of the lock illustrated on the Figure 1 ; there Figure 4 is a schematic view of a combination of elements of the lock shown on the Figure 1 ; there Figure 5 is a schematic view of another combination of lock elements shown on the Figure 1 ; there Figure 6 is a schematic view in transparency along arrow VI of the safety lock illustrated on the Figure 1 ; and, the Figure 7 is a schematic perspective view of one implementation method of the lock shown on the Figure 1 .

[0019] There Figure 1 shows a security lock 10 into which a key 12 is inserted. The security lock 10 comprises a cylinder 14 with axis of symmetry C, which cylinder 14 includes a plurality of coded washers 16 applied successively against each other to form a filter as will be explained below. The cylinder 14 has a first end 18 opposite a second end 20. The lock 10 also includes a driver 22 with axis of symmetry S mounted for rotation at the second end 20 of the cylinder 14 and coaxially with it. The driver 22 is guided in rotation, in particular by means of a cylindrical guide portion 24 through a housing (not shown), which also houses the cylinder 14. The driver 22 has a crankpin 26 opposite the cylinder 24, and a circular rim 28 towards the cylinder 24. Before detailing the driver 22, reference should be made to the Figure 3 showing the second end 20 of the cylinder 14, precisely freed from the driver 22, in order to better describe the elements it obscures on the Figure 1 .

[0020] Thus, on the Figure 3 Two curved keys appear, a first key 30 diametrically opposed to a second key 32. The keys 30 and 32 are respectively fixed to a control rod 34 and 36 which extend axially along the cylinder 14. The two keys 30 and 32 are identical and are thus respectively movable by pivoting around the axes A and B of the control rods 34 and 36, between a position close to each other and a position apart. It will be observed that the keys 30 and 32 are curved in the same direction as that of the cylinder 14. Moreover, when the keys 30 and 32 move apart, they pivot in opposite directions of rotation.

[0021] The first 30 and second 32 keys have, respectively, a first free end 38 and a second free end 40. The free ends 38 and 40 are substantially cylindrical and thus rounded. They are each equipped with a first lug 42 and a second lug 44. The lugs 42 and 44 extend laterally from the keys 30 and 32 along an axial direction of the cylinder 14. The lugs 42 and 44 are located at a predetermined distance from the free ends 38 and 40. This distance is, for example, approximately one-quarter of the length of the keys 30 and 32. The keys 30 and 32 themselves have a length substantially close to the radius of the cylinder 14.

[0022] Also, the cylinder 14, at its second end 20, has a terminal retaining washer 46 with an axial bore 48 in its center, allowing it to form a bearing as will be explained below. The terminal retaining washer 46 has no coding function, but in addition to its rotational guidance function, it also helps to keep the coded washers 16 axially supported against each other.

[0023] We will now refer to the Figure 2 showing in more detail the trainer 22. It includes a central part 50 which extends in projection from a shoulder 52. The trainer 22 also includes a circular border 54 defining two portions of slices offset axially from each other, a first proximal slice portion 56 defining the shoulder 52, and a second distal slice portion 58.

[0024] The central part 50 of the driver 22 has a cylindrical symmetry envelope with a circular base, suitable for engaging inside the axial bore 48 formed in the terminal retaining washer 46 shown on the Figure 3 The driver 22 has a blind axial orifice 60 opening axially into the central portion 50. The central portion 50 also has a transverse slot 62 extending along a transverse direction T perpendicular to the axis of symmetry of the driver 22. Thus, the transverse slot 62 has a free intersection with the blind axial orifice 60 and defines four bearing surfaces 64, 66, 68, and 70, arranged in pairs. This will be explained in more detail later in the description of the Figure 5 the function of this transverse slot 62.

[0025] Also, coach 22 as illustrated on the Figure 2 It features two V-shaped notches, a first 72 and a second 74, antisymmetric with respect to an axial plane; the V-shaped notches being made in the first portion of the proximal slice 56 of the circular border 54. The V-shaped notches 72 and 74 then define a first stop 76 and a second stop 78 substantially diametrically opposed and extending along an axial plane. The two V-shaped notches 72 and 74 respectively define substantially triangular spaces in the thickness of the first portion of the proximal slice 56 and delimited respectively by the stops 76 and 78 and the adjacent sides 80 and 82.

[0026] Furthermore, the driver 22 has two notches, a first notch 84 and a second notch 86, formed in the second portion of the slice 58. The notches 84 and 86 are diametrically opposed and open laterally into the V-shaped notches 72 and 74, respectively. Moreover, the notches 84 and 86 are antisymmetric with respect to an axial plane. They extend along an average direction away from the center of symmetry S of the driver 22, so as to form an edge prolonged by a hook-shaped flank 88 and an opposite obtuse edge 90. Furthermore, the bottoms of the notches 84 and 86 are machined in a counterclockwise direction to obtain even more pronounced hook-shaped edges 88. Furthermore, the edges forming hook 88 are rounded to obtain a notch flank with a double curvature.

[0027] It will be observed that the edges forming hook 88 extend respectively and in an axially offset manner, in relation to the first 76 and second 78 stops.

[0028] We will now turn to the Figure 4 showing precisely the keys 30, 32 respectively extended in the notches 74, 72, and the free ends 40, 38 respectively bearing against the stops 76, 78. Also shown in this figure are the control rods 34, 36 intended to control the pivoting of the keys 30, 32. They appear here because a plurality of coded washers 16 have been removed for clarity of the drawing. Furthermore, the cylinder 14 defines a keyway 92 which extends axially to the central part 50 of the driver 22. This keyway 92 axially accommodates the key 12, as illustrated by the Figure 5 on which coded washers 16 have also been removed from the cylinder 14, particularly on the side of the second end 20. Thus, the bit 94 of the key 12 appears, which, engaged in the keyway 92, comes into contact with the transverse slot 62 of the central part 50 of the driver 22. In this position, the bit 94 of the key 12 is rotationally fixed to the driver 22. It will be observed on this Figure 5 , that one of the keys 32 extends into the first V-notch 72, while its stud 44, the second, extends inside the first notch 84. It is understood that behind the Figure, the other key 30 extends into the second V-notch 74, while its stud 42 extends inside the second notch 86.

[0029] This situation is then found on the Figure 6 In a rear view of the safety lock 10, and transparently through the driver 22, we see the two keys 30 and 32 positioned close together so as to extend into the V-shaped notches 74 and 72. Furthermore, their respective free ends 38 and 40 are abutted against the second 78 and first 76 stops, respectively. It is thus understood that the driver 22 is prevented from rotating clockwise at two diametrically opposite points on the driver 22. Indeed, the keys 30 and 32 thus act as a support.

[0030] Furthermore, the two lugs 42 and 44 are located in the notches 86 and 84, respectively. Thus, when the driver 22 is forced to rotate counterclockwise, the lugs 42 and 44 engage with the hook-shaped edges 88 of the notches 84 and 86. This not only prevents the driver 22 from rotating counterclockwise but also prevents the keys 30 and 32 from separating. Indeed, the lugs 42 and 44 of the keys 30 and 32 are engaged behind the hook-shaped edges 88.

[0031] Therefore, such a security lock 10 is difficult to break since, to pick it, it is necessary not only to force the drive of the driver 22 in rotation but also to simultaneously lift the two keys 30, 32, it being noted that their movement is prohibited when the driver 22 is forced in the trigonometric direction, and is difficult when the driver 22 is forced in the opposite direction, that of the hands of a clock.

[0032] Naturally, when the bit 94 of the key 12 corresponding to the safety lock 10 is engaged in the passage 92 until it comes into contact with the driver 22, the rotation of the key 12, and consequently of the bit 94, is permitted. This sequentially causes the pivoting of the keys 30, 32 around the axes A, B of the control rods 34, 36, and therefore the separation of the keys 30, 32 from each other. The keys 30, 32 then release the two V-shaped notches 74, 72, while the corresponding pins 42, 44 release the notches 86, 84. In this way, the driver 22 is released and can be rotated by continuing the rotation of the key 12 and the bit 94.

[0033] Thus, returning to the Figure 1 It is understood that the crankpin 26 can be driven in rotation around the axis of symmetry C of the cylinder 14. The crankpin 26 can for example cause the translation of a locking member.

[0034] In particular, it can cause the translation of a longitudinal bolt 96 of a security padlock 98 as shown on the Figure 7The security padlock 98 comprises a T-shaped housing 100 with a cylindrical recess 102 having an open bottom 101 and a transverse recess 104 which it surmounts. The transverse recess 104 has two opposing ends, one 106 forming a shackle, while the other 108 has a receiving recess 110. The security padlock 98 also includes a shackle 112 mounted in the shackle of the end 106 to allow it to pivot. The hoop 112 has a free hook end 114 intended to extend into the receiving housing 110. In addition, the transverse housing 104 receives the longitudinal bolt 96, which has a hooking end 116 extending at least partially into the receiving housing 110 in order to cooperate with the free hook end 114 of the hoop 112 and thus lock it in place.The longitudinal bolt 96 is slidably returned by a spring 118 opposite its latch end 116 so that it can be forced towards the receiving housing 110. In addition, the longitudinal bolt 96 has a central slot 120.

[0035] The safety padlock 98 then comprises a safety lock as described above, housed inside the cylindrical housing 102, so that the crank 26' protrudes into the central slot 120 of the longitudinal bolt 96, while the first end 18' of the cylinder 14' extends opposite the open bottom 101. The transverse housing 104 is closed by means of a sealed cover, and the open bottom 101 is then accessible by means of a key 12' in order to unlock the shackle 112. Indeed, the rotation of the crank 26' allows the longitudinal bolt 96 to be moved in translation towards the end 106 and thus releases the free hook end 114 to allow the shackle 112 to pivot.

[0036] The safety lock of the invention can also be used to lock the door of a piece of furniture or any box, for example, a key box. It then comprises a rectangular housing and a hinged door to close said housing. A safety lock as described above is then installed on the hinged door, and the actuator is equipped with a cam to lock the hinged door onto said rectangular housing.

Claims

1. A safety lock (10) adapted to be operated with a key (12) having a coded bit (94), said safety lock including: a cylinder (14) made of coded discs (16) having two opposite ends (18, 20) and a passage way (92) opening within said two ends (18, 20); a driving member (22) rotatingly mounted to the one (20) of said two ends, said driving member comprising a central part (50) extending in front of said passage way (92) and a circular edge (54) having two opposite notches (72, 74), said bit (94) being adapted to be engaged into said passage way (92) through the other (18) of said ends to engage said central part (50); two offset wedges (30, 32) swivellingly mounted on said one of said ends (20) of said cylinder (14) to be able to engage said notches (74, 72) respectively, in order to rotatingly block said driving member (22), said bit (94) being adapted to sequentially cause the spacing apart of said wedges (30, 32) in order to release said notches (74, 72), and the rotation of said driving member (22); characterized in that, said circular edge (54) having two axially shifted slice portions (56, 58), said notches (74, 72) are provided in one (56) of said slice portions, while the other (58) of said slice portions is further provided with a notch (84) opening within one of said notches (72); and in that one of said wedges (32) is provided with a side nipple (44) intended to engage said notch (84) when the wedge (32) extends within said one of said notches (72).

2. The safety lock according to claim 1, characterized in that the other of said slice portions (58) is further provided with another notch (86) opening within the other of said notches (74), and in that the other of said wedges (30) is provided with another side nipple (42) in order to engage said another notch (86) when said another of said wedges (30) extends within said another of said notches (74).

3. The safety lock according to claim 1 or 2, characterized in that said notches (74, 72) extend in a substantially V-shape by forming each one a resting stop (78, 76).

4. The safety lock according to claim 3, characterized in that said wedges (30, 32) have each one a free end (38, 40) adapted to bear against said resting stops (78, 76).

5. The safety lock according to any of claims 1 to 4, characterized in that said notch (84, 86) extends according to a middle direction away from the center of said circular edge (54) so as to form a hook forming flank (88).

6. The safety lock according to claims 3 and 5 or 4 and 5, characterized in that said hook forming flank (88) is opposite to said corresponding stop (76, 78).

7. The safety lock according to any of claims 1 to 6, characterized in that said wedges (30, 32) are mounted respectively on two controllable rods (34, 36) extending along said cylinder (14) within two diametrically opposite positions.

8. The safety lock according to any of claims 1 to 7, characterized in that said driving member (22) has a crank pin (26) directed at the opposite of said cylinder (14).

9. A safety key box comprising a parallelepipedic housing and a hinged door to close said housing, characterized in that it comprises a safety lock according to any of claims 1 to 7, and in that said driving member is provided with a hinged cam to lock said hinged door on said parallelepipedic housing.

10. A safety padlock (98) comprising: a T-shape case (100) including a cylindrical housing (102) surmounted by a transversal housing (104) having two opposite ends (106, 108); a hoop (112) swivellingly mounted on one of said ends (106) of said transversal housing (104), said hoop (112) having a free end (114) in a hook form adapted to extend into the other of said ends (108) of said transversal housing (104); a longitudinal bolt (96) slidingly mounted within said transversal housing (104) to engage with said free end (114) as a hook into said another of said ends (108); characterized in that it comprises a safety lock according to any of claims 1 to 8, said safety lock being installed within said cylindrical housing (102) so that said driving member cooperates with said longitudinal bolt (96).