AU2020281028A1

AU2020281028A1 - A tumbler lock assembly

Info

Publication number: AU2020281028A1
Application number: AU2020281028A
Authority: AU
Inventors: Alexander Thomas Munro
Original assignee: Assa Abloy Australia Pty Ltd
Current assignee: Assa Abloy Australia Pty Ltd
Priority date: 2019-12-23
Filing date: 2020-12-01
Publication date: 2021-07-08
Also published as: CN113090114A

Abstract

This invention relates to a tumbler lock 2, for use with a mortice lock assembly 1 including a housing 9 and a barrel 12 that is rotatable relative to the housing 9. The tumbler lock 2 includes at least one tumbler 17 which is also rotatable for interaction with a locking bar 19. The barrel 12 rotates about an axis which is other than coaxial with the axis of rotation of each tumbler 17. 4 3 1 9 7 2 12 10 00 ~8 11 5 FIGURE 1 19 21 26 9 20 33 10 X 323 FIGURE 2

Description

4 3 1

9

7 2

12 10

00 ~8 11

5 FIGURE 1

19 21

26

33 9 20

X 323

FIGURE 2

ATUMBLERLOCKASSEMBLY

[0001] This invention relates to a tumbler lock, a key for use with a tumbler lock and a combination of a key and tumbler lock. More specifically the tumbler lock is of the kind that includes tumblers that rotate about a tumbler axis when the key is inserted in the keyway. The tumbler lock assembly has an application in use with a mortice lockset, and it will be convenient to hereinafter describe the invention with reference to this application. It out to be appreciated that the tumbler lock assembly will have other applications including in use with, for example entrance locksets.

BACKGROUND OF INVENTION

[0002] A mortice lockset generally includes a set of knobs or levers that are each rotatable to operate a mortice lock assembly mounted in the side of the door. The locking functionality can be provided by a lock mechanism within the mortice lock assembly housing which is controlled by a tumbler lock mounted separately to the knob or lever. The tumbler lock is operated by a key inserted into a barrel that is coded with bittings to interact with tumblers. If the key includes correctly coded bittings, the tumblers will be adjusted so as to allow the barrel to rotate about a barrel axis relative to a housing so as to adjust the mechanism within the mortice lock.

[0003] Tumblers, also referred to as detainers, come in a range of forms including pins, discs and wafers. Pin and wafer tumblers are biased towards a position whereby they extend across a shear line between the barrel and the housing, to inhibit the rotation of the barrel relative to the housing. The pin and wafer tumblers tend to move in a direction perpendicular to the barrel axis when the key is inserted, while disc tumblers rotate about the barrel axis. The discs tend to be allowed to rotate without any counter acting biasing force, and they interact with a locking bar that extends across the shear line to inhibit the rotation of the barrel relative to the housing.

[0004] The tumbler lock can also be configured with a profiled keyway to interact with a profiling groove extending longitudinally on the key blade. This interaction limits the type of lock that any one key can slide into. The unique profile is offered by locksmiths to select clients who desire some form of exclusivity. However, lock manufactures appreciate there is a finite number of combinations of profiling groves that can be formed into a key blade.

[0005] A reference herein to a patent document or other matter which is given as prior art is not to be taken as an admission that that document or matter was, in Australia, known or that the information it contains was part of the common general knowledge as at the priority date of any of the claims.

SUMMARY OF THE INVENTION

[0006] According to one aspect of this invention there is provided a tumbler lock including a housing, a barrel mounted in the housing for rotation about a barrel axis, at least one tumbler for rotation about a tumbler axis between an active condition and an inactive condition, a locking bar which is operative to prevent rotation of said barrel relative to said housing when the tumbler is in an active condition, and which is inoperative to prevent said rotation of the barrel relative to the housing when said tumbler is in an inactive condition wherein the barrel axis is other than coaxial with the tumbler axis.

[0007] The barrel axis may be lateral relative to the tumbler axis as in the case where the tumbler axis is perpendicular to the barrel axis, or angled relative to the barrel axis while still intersecting the barrel axis. The barrel axis may alternatively be skewed relative to the tumbler axis, in which case it is to the side of the tumbler axis but not intersecting the tumbler axis.

[0008] The barrel preferably includes a cavity having a tumbler portion that is configured so that the barrel supports the tumbler when in the tumbler portion. The barrel may be configured in any suitable manner to support the tumbler however it is preferred that it includes a shoulder defining in part the tumbler portion. The shoulder could be replaced by an annular groove to receive radially projecting posts on the tumbler, so as to support the tumbler while still allowing for rotation. The shoulder is preferably configured to interact with a lower portion of the tumbler so as to limit rotation of the tumbler by no more than 600. The degree of rotation may theoretically be up to 1800, however the applicant has found that rotation of the tumbler within a 600 range is provides for a range of rotation positions for coding purposes, while still allowing for relative smooth interaction between the key and the tumblers.

[0009] The barrel includes a keyway which is configured for accommodating a blade of a key, and it is preferred that the tumbler includes a post, or some form of projection, at the lower portion that projects into the keyway so as to enable the tumbler to engage with the blade of the key when in use. It is preferred that the post be rounded so that the post can smoothly rotate relative to the blade.

[0010] It is preferred that the cavity includes a locking bar portion that is configured to accommodate the locking bar within a circumference of the barrel when the tumbler is in the inactive condition.

[0011] The tumbler preferably includes an upper portion which is configured to accommodate movement of the locking bar in a radial direction when the tumbler is in the inactive condition and inhibits movement of the locking bar in the radial direction when in the active condition. The upper portion may be configured in any suitable manner, and one preferred manner includes the upper portion of the tumbler having a ledge on which the locking bar seats when the tumbler is in the inactive condition and the barrel is rotated about the barrel axis. The ledge arrangement is found suitable when the barrel axis is skewed relative to the tumbler axis, however where the barrel axis is perpendicular to the tumbler axis the ledge may be replaced by a groove extending across the diameter of the tumbler. The upper portion of the tumbler preferably includes an upper surface against which the locking bar abuts when the tumbler is in the active condition.

[0012] A tumbler lock preferably includes at least one profile element for interacting with at least one profile feature in a key, wherein the profile element is separable from the barrel. The profile element may take any suitable form, and in one preferred embodiment the at least one profile element includes a profile plate having an aperture formed therein which is configured for interacting with a profile channel formed in a surface of a blade of a key. Another alternative might include an aperture configured to interact with a profile ridge on the surface of the key. The at least one profile element may also include a barrel end driver which is fastened to the barrel, the barrel end driver having a surface that is configured for interacting with a tip of a key.

[0013] A tumbler lock preferably includes a plurality of said tumblers aligned to a side of the locking bar, however it is most preferred that plurality of tumblers are aligned on opposed sides of the locking bar. This has the advantage of increasing the number of tumblers, which in turn increases the number of coding combinations available to the locksmith.

[0014] The tumbler lock preferably includes a biasing means for biasing the locking bar in a radial direction away from the barrel axis. The biasing means may take any suitable form, and one form may include a plurality of locking bar supports which engage the locking bar, with each locking bar support being engaged by at least one biasing spring. Another alternative is for the biasing springs to engage the locking bar directly.

[0015] The housing preferably includes a longitudinal extending groove, which accommodates the locking bar when the tumbler is in the active position, whereby the locking bar extends across a shear line between the barrel and the housing into the longitudinal groove to hinder rotation of the barrel relative to the housing.

[0016] According to another aspect of this invention there is provided a key for a tumbler lock including an oblong blade having an upper side and a lower side opposed to the upper side, the upper side includes at least one bitting channel which defines a nonlinear path from a tip of the oblong blade towards a head of the key for interacting with tumblers of a tumbler lock.

[0017] The lower side of the blade may include at least one profile channel which defines a linear path from a tip of the oblong blade towards the head of the key for interacting with a profiling member of the tumbler lock. It is further preferred that the blade include a plurality of profile channels. Alternatively, the profile channel(s) may be included in the upper side of the blade.

[0018] The number of bitting channels may vary depending upon the number of series of tumblers in the tumbler lock, and in a preferred arrangement the key includes plurality of bitting channels, each of the bitting channels defining a unique pathway relative to the at least one profiling channel. It is preferred that each bitting channel has an entrance which is splayed so as to facilitate interaction with the tumblers of the tumbler lock. The degree to which the entrance is splayed may vary depending upon the dree of rotation required for the tumblers, and in the preferred embodiment the splayed angle is no less than 70°.

[0019] According to further still another aspect of this invention there is provided a key as herein before defined in combination with a tumbler lock as herein before defined.

[0020] It will be convenient to hereinafter describe the invention in greater detail by reference to the attached illustrations of a preferred embodiment of the tumbler lock assembly and key according to the invention. The particularity of those illustrations, and the accompanying detailed description is not to be understood as superseding the generality of the preceding definition of the invention according to each of its aspects.

BRIEF DESCRIPTION OF DRAWINGS

[0021] In order that the invention may be more fully understood, some embodiments will now be described with reference to the Figures in which:

[0022] Figure 1 is an isometric view of a mortice lock in combination with a tumbler lock.

[0023] Figure 2 is an exploded isometric view of the tumbler lock from Figure 1 according to a preferred embodiment of the invention.

[0024] Figure 3 is a plan view of the barrel from Figure 2.

[0025] Figure 4 is a long section view through B-B from Figure 3.

[0026] Figure 5 is an isometric view of a tumbler form Figure 2.

[0027] Figure 6 is a bottom view of the tumbler from Figure 5

[0028] Figure 7 is a partial assembled view of the barrel, tumblers and locking bar form Figure 2, with the tumblers in the active condition.

[0029] Figure 8 is a long section view through C-C from Figure 7

[0030] Figure 9 is the partial assembled view from Figure 7, with the key inserted in the barrel and the tumblers in an inactive condition.

[0031] Figure 10 is a cross sectional view through the housing and barrel showing the tumblers in the active condition.

[0032] Figure 11 is the cross sectional view from figure 10 with the key inserted, the tumblers in the inactive condition and the barrel rotated.

[0033] Figure 12 is an isometric view of the key showing a lower surface of the blade, and the profile plate.

[0034] Figure 13 is an end view of the key inserted into the profile plate.

DETAILED DESCRIPTION

[0035] Referring now to Figure 1 which is an isometric view of a mortice lock 1 assembly in conjunction with a preferred embodiment of a tumbler lock 2 according to the invention. The mortice lock assembly 1 illustrated includes a casing 3 having a faceplate 4 attached thereto, with a latchbolt 5 projecting out through the faceplate 4. A fastening pin 6 is shown in front of the faceplate 4, whereby in use the pin 6 is inserted through a left or right aperture 7 formed in the faceplate 4, to locate within an aperture 8 formed at the rear end of the tumbler lock housing 9. Figure 1 also illustrates a key , or more specifically the head 11 of a key inserted into a barrel 12 of the tumbler lock 2. The person skilled in the art will appreciate that to this extent the tumbler lock 2 looks similar to existing oval tumbler locks available in the market.

[0036] Figure 2 illustrates the key 10 in front of the housing 9, and the barrel 12 adjacent a rear of the housing 9. The barrel 12 is formed with a keyway 13 from a front thereof which is shaped to receive a blade portion 14 of the key 10. The barrel 12 is also formed with a cavity 15 extending from the cylindrical surface. The cavity 15 includes a tumbler portion16 (see also Figure 8) which is shaped to accommodate two series of tumblers 17, and a locking bar portion 18 which is shaped to accommodate a locking bar 19 in a manner than will be described in greater detail with reference to latter illustrations.

[0037] The tumbler lock 2 also includes a front locking bar support 20 and a rear locking bar support 21 which are located in a front slot 22 and a rear slot 23 formed in the barrel 12 respectively. Each of the front locking bar support 20 and rear locking bar support 21 are biased away from a barrel axis X-X, under the influence of a pair of front springs 24 and rear springs 25 respectively. The front locking bar support 20 and rear locking bar support 21 engage an underside of the locking bar 19, so as to urge the locking bar 19 radially away from the barrel axis X-X. The locking bar 19 interacts between each of the tumblers 17 and the housing 9 so as to control rotation of the barrel 12 relative to the housing 9 in a manner that we describe in greater detail by reference to latter illustrations.

[0038] Figure 2 also illustrates the tumbler lock 12 including a barrel end driver 26 which is attached to a rear of the barrel 12 by a pair of screws (not shown). The rear of the barrel 12 is formed with a groove 27 (see also Figure 3) which extends radially across the diameter of the barrel 12. The groove 27 is configured to receive a rectangular protrusion 28 extending across the diameter of the barrel end driver 26 so as to facilitate the driving connection between the barrel 12 and the barrel end driver 26. It should be noted from Figure 2 that the protrusion 28 includes a notch 29 formed at its midpoint, which is occupied by a tip of the blade 14 when the key 10 is fully inserted into the keyway 13. The interaction between the notch 29 and the tip of the blade 14 will be explained in greater detail by reference to latter illustrations.

[0039] A profile plate 30 is included for location over the front of the barrel 12 when the tumbler lock 2 is assembled. The profile plate 30 has a substantially rectangular aperture formed therein which is aligned with the keyway 13 in the barrel 12. The aperture in the profile plate 30 is defined in part by a pair of projections 31 which interact with profile channels 32 (see also Figure 12) formed in a lower surface of the blade 14.

[0040] Figure 2 also illustrates a C-clip 33 which interacts between the barrel end driver 26 and a groove (not shown) formed internally within the housing 9, to retain the barrel end driver 26 and therefore barrel 12 and profile plate 30 within the housing 9 when assembled.

[0041] Referring now to Figure 3 which illustrates a plan view of the barrel 12 from Figure 2 and in particular the tumbler portion 16 of the cavity 15 being formed by a plurality of substantially cylindrical bores positioned either side of the barrel axis X-X. The number and location of tumbler portions 16 may vary from that as illustrated in the drawings, and to that extent it could be envisaged that instead of being offset from the barrel axis X-X, the number of tumbler portions 16 could be halved and aligned with the barrel axis X-X.

[0042] It can be also noted from Figure 3 that each tumbler portion 16 is defined in part by a crescent shaped shoulder 34 extending around slightly more than 50 percent of the circumference of each cylindrical bore. The shape and size of the shoulder 34 is configured to seat the tumbler 17 thereon, and interact with a lower portion 35 (see Figure 5) of the tumbler in such a way to limit the rotation of the tumbler 17 within the tumbler portion 16.

[0043] Figure 3 also illustrates the locking bar portion 18 of the cavity 15 extending the length of the barrel 12. The locking bar portion 18 is shaped to accommodate the locking bar 19 within the circumference of the barrel 12 when each tumbler 17 is rotated to an inactive condition. This interaction will be explained further later in the specification.

[0044] Referring now to Figure 4 which illustrates the tumbler portion 16 of the cavity 15 leading to the keyway 13 and separated by the shoulder 34. This arrangement is designed to suit the shape of the tumbler 17 as illustrated in Figure 5 and 6, and could vary if the shape of the tumbler 17 varied. Each tumbler 17 has a middle portion 36 of a greater diameter to the lower portion 35 so that the middle portion 36 seats on top the shoulder 34. The lower portion 35 is substantially cylindrical for the majority of its circumference with tangential surfaces 37 converging towards a side of the tumbler 17. A post 38 is positioned offset from the center of the tumbler 17 and associated with the side of the tumbler 17 where the tangential surfaces 37 converge. The tangential surfaces 37 can interact with each ends of the shoulder 34 respectively when the tumbler 17 is rotated about its axis Y-Y(hereinafter the tumbler axis), to limit the rotation of the tumbler 17 within the tumbler portion 16. The preferred arrangement as illustrated limits rotation through no more than 60 degrees, however this may vary if a greater degree of rotation is preferred. The Applicant has appreciated however that a 60 degree of rotation, 30 degrees of rotation either side of a center line B-B (see Figure 3), allows for smooth interaction between the key 10 and the tumbler 17 when inserting the key 10 into the keyway 13, while still providing for a range of rotational positions for the tumbler 17 for varying the coding.

[0045] Figure 5 also illustrates a ledge 39 formed at an upper portion 40 of the tumbler 17. The ledge 39 is shaped so as to accommodate a portion of the locking bar 19 when the tumbler 17 is rotated to an inactive condition. The position of the ledge 39 relative to the post 38 will set the coding of the tumbler 17, and to that extent it is desirable for the tumbler lock 2 to have tumblers 17 with the ledge 39 in a range of positions. The shape also of the ledge 39 as illustrated in Figure 5 may vary depending upon the shape of the locking bar 19. The upper portion 40 of the tumbler 17 may also include additional ledges at different rotational positions, possibly at different heights, to form a "false flat" allowing insufficient accommodation of the locking bar 19. These false flats are designed so as to confuse an unauthorised person attempting to pick the tumbler lock 2.

[0046] Referring now to Figure 7 which illustrates the key 10 aligned with the barrel 12. It should be noted from Figure 7 that the blade 14 has a first side with a pair of bitting channels 41 formed therein. Each bitting channel 41 defines a unique serpentine pathway leading from the tip of the blade 14 towards the head 11. Each bitting channel 41 at the tip of the blade 14 is splayed so as to facilitate capturing the post 38 (see Figure 6) of the tumbler 17 as it enters the bitting channel 41. The preferred splayed angle is 70° as this will accommodate the 600 of rotation of each tumbler 17, however this can be varied to accommodate different degrees of rotation of the tumblers 17.

[0047] It should also be noted from Figure 7 that each of the tumblers 17 are in an active position, whereby each ledge 39 is out of alignment with the locking bar 19 thereby hindering it from moving. It can be appreciated from Figure 8 that with at least one of the tumblers 17 in the active position the locking bar 19 is hindered from being moved from its position proud of the circumference of the barrel 12. It can also be appreciated from Figure 8 that each post 38 projects into the keyway 13 so that it can interact with the bitting channel 41 on the key 10.

[0048] Referring now to Figure 9 which illustrates the key 10 having been inserted into the keyway 13 of the barrel 12. When the correctly coded key 10 is inserted each tumbler 17 interacts with the bitting channel 41 to rotate about its tumbler axis 10 (Y Y). When the key 10 is fully inserted each tumbler 17 is rotated to a position whereby each ledge 39 is aligned with the locking bar 19, considered to be the inactive condition for the tumblers 17.

[0049] It should be noted that Figures 7 and 9 do not show the barrel end driver 26 and that the tip of the blade 14 locates within the slot 27 (see Figure 9) at the rear of the barrel 12 when fully inserted. If the barrel end driver 26 did not include a notch 29, the blade 14 would be inserted to a different position relative to the tumblers 17, and as such the configuration of the bitting channels 41 would not adjust all tumblers 17 to the inactive condition. Another option to the notch 29 in the barrel end driver 26 is for the blade 14 to include at least one shoulder (not shown) adjacent the head 11 to limit the extent to which the blade 14 can be inserted into the keyway 13.

[0050] Referring now to Figures 10 and 11 which correspond with Figures 7 and 9 respectively, and it can be appreciated from Figure 10 that with the tumblers 17 in the active condition, the locking bar 19 sits proud of the circumference of the barrel 12 to locate within a longitudinal groove 42 formed in the housing 9. This arrangement prevents rotation of the barrel 12 relative to the housing 9. In comparison in Figure 11, the blade 14 has been inserted into the keyway 13 so as to rotate the tumblers 17 to align each ledge 39 with the locking bar 19. When each tumbler 17 is so aligned, rotation of the barrel 12 relative to the housing 9 will allow the upper surface of the locking bar 19 to cam off the surface of the longitudinal groove 42 to move radially towards the barrel axis X-X.

[0051] Referring now to Figures 12 and 13 which illustrate the lower side of the blade 14 of the key 10, and in particular the unique profile channels 32. The number and location of the profile channels 32 may vary from that as illustrated, and as can the shape of each respective profile channel 32. While the keyway 13 within the barrel could be shaped to provide the projections 31, the Applicant has appreciated that this can be achieved by the installation of the profile plate 30 in front of the barrel 12. It is preferred that the profile plate 30 interact with the barrel 12 in such ways to inhibit rotation of the profile plate 30 relative to the barrel 12. Further profiling features may be included into the key 10, such as a unique shaped tip to the blade 14 to interact with a unique shaped leading face of the barrel end driver 26.

[0052] It ought to be appreciated from the foregoing that the use of rotating pin tumblers 17 in combination with a locking bar 19 is relatively unique. Furthermore, the utilisation of two sets of tumblers 17, which are each independently rotatable about a tumbler axis which are each skewed relative to the barrel axis, increases the number of tumblers 17 and thereby increases the number of key coding combinations available to the locksmith. Still furthermore, the utilisation of profiling channels 41 and profiling options at the tip of the blade 14 relative to the barrel end driver 26 enables the locksmith to provide further unique keying coding arrangements.

[0053] Various alterations and/or additions may be introduced into the tumbler lock as hereinbefore described without departing from the spirit or ambit of the invention.

Claims

THE CLAIMS DEFINING THE INVENTION ARE AS FOLLOWS:

1. A tumbler lock including a housing, a barrel mounted in the housing for rotation about a barrel axis, at least one tumbler for rotation about a tumbler axis between an active condition and an inactive condition, a locking bar which is operative to prevent rotation of said barrel relative to said housing when the tumbler is in an active condition, and which is inoperative to prevent said rotation of the barrel relative to the housing when said tumbler is in an inactive condition wherein the barrel axis is other than coaxial with the tumbler axis.

2. A tumbler lock according to claim 1 wherein the barrel axis is lateral relative to the tumbler axis.

3. A tumbler lock according to claim 1 or 2 wherein the barrel axis is skewed relative to the tumbler axis.

4. A tumbler lock according to any one of the preceding claims wherein the barrel includes a cavity having a tumbler portion that is configured so that the barrel supports the tumbler when in the tumbler portion.

5. A tumbler lock according to claim 4 wherein the barrel includes a shoulder defining in part the tumbler portion, the shoulder being configured to interact with a lower portion of the tumbler so as to limit rotation of the tumbler by no more than 600.

6. A tumbler lock according to claim 4 wherein the barrel includes a keyway which is configured for accommodating a blade of a key, wherein the tumbler includes a post at the lower portion that projects into the keyway so as to enable the tumbler to engage with the blade of the key when in use.

7. A tumbler lock according to any one of claims 4 to 6 wherein the cavity includes a locking bar portion that is configured to accommodate the locking bar within a circumference of the barrel when the tumbler is in the inactive condition.

8. A tumbler lock according to any one of the preceding claims wherein the tumbler includes an upper portion which is configured to accommodate movement of the locking bar in a radial direction when the tumbler is in the inactive condition and inhibits movement of the locking bar in the radial direction when in the active condition.

9. A tumbler lock according to claim 8 wherein the upper portion of the tumbler includes a ledge on which the locking bar seats when the tumbler is in the inactive condition and the barrel is rotated about the barrel axis.

10. A tumbler lock according to claim 9 wherein the upper portion of the tumbler includes an upper surface against which the locking bar abuts when the tumbler is in the active condition.

11. A tumbler lock according to any one of the proceeding claims including at least one profile element for interacting with at least one profile feature in a key, wherein the profile element is separable from the barrel.

12. A tumbler lock according to claim 11 wherein the at least one profile element includes a profile plate having an aperture formed therein which is configured for interacting with a profile channel formed in a surface of a blade of a key.

13. A tumbler lock according to claim 11 or 12 wherein the at least one profile element includes a barrel end driver which is fastened to the barrel, the barrel end driver having a surface that is configured for interacting with a tip of a key.

14. A tumbler lock according to any one of the preceding claims wherein the at least one tumbler includes a plurality of tumblers aligned to a side of the locking bar.

15. A tumbler lock according to any one of claims 1 to 13 wherein the at least one tumbler includes a plurality of tumblers aligned on opposed sides of the locking bar.

16. A tumbler lock according to any one of the preceding claims including a biasing means for biasing the locking bar in a radial direction away from the barrel axis.

17. A tumbler lock according to claim 16 wherein the biasing means includes a plurality of locking bar supports which engage the locking bar, with each locking bar support being engaged by at least one biasing spring.

18. A tumbler lock according to any one of the preceding claims wherein the housing includes a longitudinal extending groove, which accommodates the locking bar when the tumbler is in the active position, whereby the locking bar extends across a shear line between the barrel and the housing into the longitudinal groove to hinder rotation of the barrel relative to the housing.

19. A key for a tumbler lock including an oblong blade having an upper side and a lower side opposed to the upper side, the upper side includes at least one bitting channel which defines a nonlinear path from a tip of the oblong blade towards a head of the key for interacting with tumblers of a tumbler lock.

20. A key according to claim 19 wherein the lower side includes at least one profile channel which defines a linear path from a tip of the oblong blade towards the head of the key for interacting with a profiling member of the tumbler lock.

21. A key for a tumbler lock according to claim 20 including a plurality of bitting channels, each of the bitting channels defining a unique pathway relative to the at least one profiling channel.

22. A key for a tumbler lock according to claim 21 wherein each bitting channel has an entrance which is splayed at an angle of no less than 700.

23. A key for a tumbler lock according to claim 21 including a plurality of profile channels on the lower side.

24. A key according to any one of claims 18 to 23 in combination with a tumbler lock according to any one of claims 1 to 18.