Classifications

• • E—FIXED CONSTRUCTIONS
  • E05—LOCKS; KEYS; WINDOW OR DOOR FITTINGS; SAFES
  • E05B—LOCKS; ACCESSORIES THEREFOR; HANDCUFFS
  • E05B27/00—Cylinder locks or other locks with tumbler pins or balls that are set by pushing the key in
  • E05B27/0042—Cylinder locks or other locks with tumbler pins or balls that are set by pushing the key in with additional key identifying function, e.g. with use of additional key operated rotor-blocking elements, not of split pin tumbler type
• • E—FIXED CONSTRUCTIONS
  • E05—LOCKS; KEYS; WINDOW OR DOOR FITTINGS; SAFES
  • E05B—LOCKS; ACCESSORIES THEREFOR; HANDCUFFS
  • E05B27/00—Cylinder locks or other locks with tumbler pins or balls that are set by pushing the key in

Definitions

• the present invention relates to an improvement in the design of locks. More specifically, the present invention is concerned with improvements to pin-tumbler type locks.
• a conventional pin-tumbler lock cylinder comprises a rotor rotatably mounted within a stator.
• the rotor has an axial keyway and a plurality of transverse holes which are aligned with blind passages in the stator.
• a pair of locking pins in mutual abutment are slidably mounted in each of said passages and biased by a spring located in the blind passage such that one pin of each pair is located in the rotor and the other pin of each pair projects across the interface between the rotor and stator so preventing rotation of the rotor.
• the pins When the correct key is inserted, the pins are urged against their bias to a position in which the interfaces between the pins of each pair are aligned with the interface between the rotor and stator, thereby allowing rotation of the rotor. On rotation of the rotor, one pin of each pair is retained in the stator, the other in the rotor. If the wrong key is inserted, one or more pair(s) of pins is/are misaligned thereby preventing rotation.
• Such a lock is vulnerable to being picked by a method in which a tool is inserted into the keyway and a slight torsion applied while a second tool is used to sequentially urge each pair of pins into alignment.
• the ease with which this is achieved is dependent upon the tolerances at which the pins, passages and transverse holes are machined.
• the stator is part cylindrical with a lobed region in which the pins are located. Such a stator is relatively difficult and expensive to manufacture.
• European Patent Specification EP 067388 A2 discloses a rotary cylinder lock including not only conventional spring loaded tumbler pins, but also, at right angles thereto, opposed springless detent pins which have rounded heads arranged at the periphery of the lock core.
• European Patent Specification EP 0756052 A1 discloses a cylinder lock with opposing pairs of locking pins and counter pins, with respective springs acting on the counter pins. When there is no key in the lock cylinder, the respective facing ends of a pair of locking pins interengage, with rotation of the cylinder being prevented, in the normal manner, by one counter pin being across the interface between the lock cylinder and its housing.
• a key-operable lock cylinder comprising a rotor, a stator, said rotor mounted within the stator for rotation about its axis, a keyway extending axially into the rotor, a plurality of locking pins and a plurality of transverse passageways extending through said rotor and said stator and intersecting said keyway, a pair of said locking pins being slidably mounted in each passageway, characterised in that for each pair of said locking pins, each locking pin of the pair is resiliently biased by a respective biasing means associated with the locking pin, so that the locking pins of each pair are in mutual abutment within the keyway with one locking pin of each pair projecting across an interface between the rotor and stator so as to prevent rotation of the rotor, whereas in use, when a complementary key is inserted in the keyway, the locking pins are movable by said key such that all the locking pins become located entirely within the rotor,
• the stator may have a circular section. This is easier and less expensive to manufacture than the conventional lobed stator.
• the total length of a pair of pins may be less than the diameter of the rotor, such that the pins of a pair do not necessarily abut when the complementary key is in the keyway.
• the smaller the total length of a pair of pins relative to the diameter of the rotor the less accuracy is required in positioning of the pins to allow the rotor to rotate, so reducing the security of the lock cylinder.
• the total length of the pins is substantially the same as the diameter of the rotor.
• the pins of a pair will be in mutual abutment when the complementary key is in the keyway and there will only be one location along the transverse passageway where abutment of the pins is possible to allow rotation of the rotor.
• the pins may have different lengths.
• the complementary key must correctly position each pair of pins.
• the number of different lengths of pin and the number of pairs of pins determines the number of possible key configurations.
• a first pin of each pair is selected from one of five lengths of pin, said five lengths chosen such that the second pin of each pair may be selected from the same five lengths of pin, such that the total length of the pair is substantially the same as the diameter of the rotor.
• the number of possible key combinations is increased by varying the axial spacing of the transverse passageways between different lock cylinders.
• one pin of each pair is biased more strongly than the other pin of the pair.
• the shorter pin is more strongly biased. This helps to ensure that one pin of each pair projects across the interface between the rotor and stator when no key is in the keyway.
• the biasing means is a compression spring.
• the pins are shaped (e.g. tapered, ramped or curved) at the ends of abutment so as to facilitate movement of the pins by the key.
• the pins are tapered.
• the keyway has a centre line which is offset from the axis of the rotor.
• a key having a handle and a shank, characterised in that said shank is adapted to fit, in use, in a keyway of a lock cylinder and is provided with a row of recesses along its length on a first major surface and a row of recesses along its length on an opposite major surface, such that said recesses on the first and the opposite major surfaces are aligned in pairs so as to be capable of accommodating locking pins of said lock cylinder, the recesses of each of said aligned pairs of recesses being interconnected.
• the recesses of an aligned pair are of different depths.
• the position of the restriction relative to the first and opposite major surfaces may vary from one passage to another.
• first and second rows of aligned recesses are provided, said rows being offset by an equal distance from a centre line of the shank and each recess in the first row on the first major surface being identical to the corresponding recess in the second row on the opposite major surface, similarly for the recesses in the second row on the first major surface and the corresponding recesses in the first row on the opposite major surface.
• the shank of the key has a C 2 -axis of rotational symmetry, such that when the key is inserted in its complementary lock having a keyway with a centre line offset from the axis of the rotor, the key can operate the lock irrespective of the orientation of the shank in the keyway.
• the shank is tapered at an end remote from the handle so that in use, separation of said locking pins to allow insertion of the shank into said lock cylinder keyway is facilitated.
• the recesses are tapered.
• the lock cylinder 2 shown is that which is more fully described in copending British Patent Application No. 9715111.2.
• the lock cylinder 2 comprises a cylindrical rotor 4, a stator 6 of annular cross section and a cam 8.
• the rotor 4 has an axially extending keyway 10 which is eccentrically located along a diameter of the rotor 4.
• the rotor 4 is received by and is a close sliding fit in the stator 6.
• the cam 8 is driveably coupled with the rotor 4.
• a row of six transverse passages 12 pass through the rotor 4 and stator 6 intersecting the keyway 10.
• a region 12a of each passage 12 through the stator 6 is narrower than a region 12b of the passage 12 through the rotor 4.
• an annular seat 14 is provided at each interface of the passage 12 with the keyway 10.
• each passage 12 is located a pair of locking pins 16,16'.
• Each pin 16,16' has a tapered end region 16a, an annular rim 16b, a stepped region 16c and a cylindrical end region 16d. In a rest position shown (Fig 2), the pins 16,16' abut each other at ends 16e adjacent the tapered end regions 16a.
• the clearance between the end region 16d of the pin 16 and the region 12a of the passage 12 is not critical.
• the pins 16, 16' are resiliently biased towards each other by a compression spring 18, 18' associated with each pin.
• Each spring 18,18' is held in place by the annular rim 16b of its associated pin 16, 16, at one end, and an annular collar 20 at a second end, said collar 20 abutting the stator 6 at an interface 22 between the rotor 4 and stator 6.
• one compression spring 18' is more strongly biased. In the case where the pins 16, 16' are of different lengths, the shorter pin 16' is provided with the more strongly biased spring 18' (as shown, Fig 2).
• each pin 16, 16' the distance from the end 16e of the pin 16, 16' to the rim 16b is such that in the rest position shown (Fig 2) the longer pin 16 projects across the interface 22 between the rotor 4 and stator 6. If the pins 16, 16' are equal in length, either may be provided with the more resilient spring 18'.
• the lock as described is secure against picking by the previously mentioned method of applying torsion. Although it might be possible to urge one pin 16,16' outwardly, the other pin 16',16 will become easily locked across the interface 22 because the bias of the relatively weak spring 18',18 will be overcome by any slight torsion. Physically pulling the pin 16',16 into the rotor 4 would be extremely difficult.
• a key 30 comprises an integrally formed handle 32 and a shank 34.
• the shank 34 is tapered at a free end 36.
• the shank 34 On a first major surface 38a, the shank 34 has first 40a and second 40b rows of tapered recesses 42a, 42a' along its length, said rows 40a, 40b being positioned either side of a centre line.
• the recesses 42a, 42a' interconnect with tapered recesses 42b, 42b' on an opposite major surface 38b of the shank 34.
• the depth of the interconnecting recess 42b on the opposite major surface 38b is the same as the depth of the recess 42a' in the same row position of the second row 40b of the first major surface 38b, similarly for the second row 40b, i.e the shank 34 has a C 2 -axis of rotational symmetry along its length.
• the shank 34 of the complementary key 30 In order to free the rotor 4 for rotation, the shank 34 of the complementary key 30 must be inserted in the keyway 10. This is facilitated by the tapered end region 36 of the key 30 which moves the pins 16, 16' apart as the shank 34 is inserted.
• the symmetrical nature of the shank 34 removes the requirement of placing the key 30 in the keyway 10 in the correct orientation, since either of the possible orientations will have the same effect.
• the complementary key 30 is correctly positioned in the lock and the first row 40a of interconnected recesses 42a, 42b on the shank 34 is aligned with the locking pins 16, 16'.
• the other row 40b of interconnecting recesses 42a', 42b' is inoperative and not shown.
• the pins 16, 16' are urged into and received into the recesses 42a, 42b, the pins 16, 16' being a close fit therein.
• the ends 16e of the pins 16, 16' of a pair may abut, but the radial position of each pin 16, 16' is primarily determined by the depth of the recess 42a, 42b in which it is seated.
• the pins 16, 16' and recesses 42a, 42b correspond so that the end regions 16d of the pins 16, 16' do not project across the interface 22 between the rotor 4 and the stator 6, so allowing the rotor 4 to be turned.
• FIG 5 an alternative embodiment is shown in which, with the key 30 correctly positioned in the keyway 10, one pin 16 is not in contact with the shank 34 of the key 30, so that only the radial position of the second pin 16' is determined by the depth of the recess 42b in which it is seated, the radial position of the first pin 16 being solely determined by the position of the second pin 16' with which it is in abutment.
• the second pin 16' which is seated in the recess 42b of the key 30 is provided with the more resilient spring 18'.

Landscapes

• Lock And Its Accessories (AREA)
• Fluid-Damping Devices (AREA)
• Iron Core Of Rotating Electric Machines (AREA)
• Pens And Brushes (AREA)
• Preventing Unauthorised Actuation Of Valves (AREA)
• Lubrication Of Internal Combustion Engines (AREA)

Applications Claiming Priority (2)

Publications (3)

Family

ID=10816029

Family Applications (1)

Country Status (8)

Cited By (3)

Families Citing this family (2)

Family Cites Families (5)

• 1997
  • 1997-07-18 GB GB9715114A patent/GB9715114D0/en active Pending
• 1998
  • 1998-07-15 DE DE69817936T patent/DE69817936T2/de not_active Expired - Lifetime
  • 1998-07-15 DK DK98305619T patent/DK0892130T3/da active
  • 1998-07-15 ES ES98305619T patent/ES2202751T3/es not_active Expired - Lifetime
  • 1998-07-15 PT PT98305619T patent/PT892130E/pt unknown
  • 1998-07-15 AT AT98305619T patent/ATE249563T1/de active
  • 1998-07-15 EP EP98305619A patent/EP0892130B1/en not_active Expired - Lifetime
• 1999
  • 1999-02-24 HK HK99100747A patent/HK1015846A1/xx not_active IP Right Cessation

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