Patent EA-001840-B1 (EA)
Title: Combination of a cylinder lock and a key
Inventor: KIISKI SEPPO
IPC: E05B29/08
Filed: 1999-09-24
Abstract: 1. A combination of a cylinder lock and a key (2) for the lock, the cylinder lock comprising a lock body (1), a turnable lock cylinder (3) located inside the lock body (1) and having a slot (8) therein, a set of locking discs (4, 6) located inside the lock cylinder (3) and each provided with at least one peripheral notch (4b, 6b) determining the opening combination of the lock and with an opening (4a, 6a) for receiving the key, and a locking bar (7) which, in a locking position, prevents turning of the lock cylinder (3) relative to the lock body (1), the key (2) having a combination surface for each locking disc (4, 6), the combination surfaces being arranged so that, on insertion of the key into the lock and turning of the key, the locking discs (4, 6) are turnable into positions, in which their peripheral notches (4b, 6b) form a uniform channel at the position of the locking bar (7) and the said slot (8) in the lock cylinder (3) into which the locking bar (7) can enter to release the lock cylinder (3) for turning relative to the lock body (1), whereby at least one of the locking discs (4) has a key opening (4a) which includes at least two separate counter surfaces (4a11, 4a12) which can be arranged, in cooperation with one combination surface of the key (2) corresponding to said locking disc (4), to turn the locking disc (4) into the opening position of the lock starting from the same initial position of the key (2), characterised in that said counter surfaces (4a11, 4a12) in the key opening (4a) of said at least one locking disc (4) are so dimensioned and arranged relative to each other that for part of at least one of the counter surfaces (4a11, 4a12) at least two different combination values can be selected for the corresponding combination surface of the key (2). 2. A combination according to claim 1, characterised in that the key opening (4a) of each code locking disc (4), which can be provided with different combination values, has, for one turning direction of the key, two said counter surfaces (4a11, 4a12) which are spaced at a distance from each other and are located at a different angle with regard to a central axis (D) of the key opening (4a) of the locking disc so that their mutual angular pitch is preferably about 30 degree . 3. A combination according to claim 1 or 2, characterised in that the counter surface (4a12) in the key opening (4a) of the code locking disc (4) corresponding to larger turning angles of the key (2) extends substantially to an axis (E) normal to a central axis (D) of the key opening (4a). 4. A combination according to claim 2 or 3, characterised in that the key openings (4a) of the lock's code locking discs (4) are at least substantially identical and formed so that the code locking discs (4) turn with the key (2) only after the key (2) is turned a particular angle, for instance about 15 degree , from the initial insertion position of the key (2). 5. A combination according to any one of the preceding claims, characterised in that the lock includes at least one lifting 0-locking disc (6) known per se which turns whenever the inserted key (2) is turned in the lock and the key opening (6a) of which is smaller than the key opening (4a) of the normal code locking discs (4). 6. A combination according to any one of the preceding claims, characterised in that when the lock is operable in one turning direction the side in the key opening (4a) of the code locking discs (4) opposite to the counter surfaces (4a11, 4a12) relative to a central axis (D) comprises a return surface (4a') which is arranged to return the locking discs (4) in cooperation with the key (2) into the locking position of the lock mechanism. 7. A combination according to claim 6, characterised in that said return surface (4a') is arranged on the same plane with one of said counter surfaces (4a12, 4a32) in the locking disc (4). 8. A combination according to any one of claims 1 to 5, characterised in that, when the lock is operable in both turning directions, the code locking discs (4) have four counter surfaces (4a11, 4a12, 4a31, 4a32; 4a21, 4a22, 4a41, 4a42) for each turning direction, the counter surfaces for the same turning direction being located in pairs in the key opening (4a) diametrically on either side of the turning axis (D') of the locking disc (4). 9. A key blank of a key for a combination according to any one of the preceding claims, the key blank having a shank (2a), characterised in that the basic form of said shank (2a) in the perpendicular cross-sectional plane of the shank and excluding any possible profile grooves or corresponding grooves (2f) extending over the shank of the key is substantially rectangular with at least one corner being replaced by at least one bevel surface (2e1) which forms at least one combination surface. 10. A key blank according to claim 9, characterised in that said bevel surface (2e1) includes two combination surfaces with different combination values. 11. A key blank according to claim 9 or 10, characterised in that said bevel surface (2e1) forms in the perpendicular cross-sectional plane of the shank (2b) of the key blank an angle of 20 DEG -30 DEG , preferably an angle of about 25 degree , with the central axis (B) extending in the direction of the longer side of the shank in said cross-sectional plane. 12. A key blank according to claim 10 or 11, characterised in that said bevel surface (2e1) is divided into two parts extending mutually in different directions and each forming one combination surface. 13. A key blank according to claim 10 or 11, characterised in that said bevel surface (2e1) is divided into two at least substantially parallel parts separated from each other by a step or the like and each forming one combination surface. 14. A key blank according to any one of claims 9 to 13, characterised in that the shank (2b) of the key blank is symmetrical as to the parts located diametrically opposite each other with regard to the central axis (A) of the shank so that its at least two corners are provided with said at least one bevel surface (2e1, 2e3). 15. A key blank according to any one of claims 9 to 14, characterised in that all corners of the shank (2b) of the key blank are provided with said at least one bevel surface (2e1, 2e2, 2e3, 2e4) so that the shank of the key blank is symmetrical with regard to both the central axis (B) parallel to the perpendicular cross-sectional plane of the shank and an axis (C) normal thereto. 16. A key blank according to any one of claims 9 to 15, characterised in that, when the key blank is intended for a lock operable only in one turning direction, the bevel surface of every second corner of the shank (2b) is arranged to operate as a return surface for the locking discs (4, 6). 17. A key for a combination according to any one of the preceding claims 1 to 8 and/or made from a key blank according to any one of the preceding claims 9 to 16, characterised in that the basic form of the shank (2a) of the key blank in the perpendicular cross-sectional plane of the shank exclusive of any possible profile grooves or corresponding grooves (2f) extending over the shank of the key is substantially rectangular so that its at least one corner is replaced by at least one bevel surface (2e1) for providing combination surfaces in the key corresponding to the code locking discs (4) in the lock, in that said at least one bevel surface (2e1) forms at least one selectable combination surface, and in that the value of other combination surfaces in the key is determined on the basis of the combination of the angle of the cut and the length of the cut surface of the cuts to be made in said bevel surface (2e1). 18. A key according to claim 17, characterised in that said bevel surface (2e1) comprises two combination surfaces having different combination values. 19. A key according to claim 17 or 18, characterised in that the angular pitch between cuts corresponding to successive combination values is about 15 degree . 20. A key according to any one of claims 17 to 19, characterised in that the length of the cut surfaces corresponding to different combination values is determined so that the extreme ends thereof are located at highest on three different peripheral surfaces (R1, R2, R3) measured from the central axis (A) of the shank (2b) of the key. 21. A key according to claim 20, characterised in that the extreme ends of the cut surfaces providing for turning movement for the locking discs and corresponding to different combination values are located on two different peripheral surfaces (R1, R2) measured from the central axis (A) of the shank (2b) of the key. 22. A key according to claim 20 or 21, characterised in that the combination surfaces of the key extending to the same peripheral surface (R1, R2) are located mutually with equal pitch. 23. A key according to any one of claims 17 to 22, characterised in that the parts of the combination cuts diametrically opposite each other with regard to the central axis (A) of the shank (2b) of the key are located symmetrically. 24. A key according to any one of claims 17 to 23, characterised in that the key includes four cut surfaces (2e1, 2e2, 2e3, 2e4) for each code locking disc (4) so that the combination cuts located diametrically opposite each other with regard to the central axis (A) of the shank (2b) of the key are identical.