GB2326187A - Locks and keys - Google Patents

Abstract

A lever lock has a thrower (17) with a barrel (22) journalled at each end in the lock case. The barrel has a longitudinal passageway opening through a longitudinal slot (26) to pass key bit (35) and opening at each end at two opposed circumferential locations. The corresponding key (32) has a pin configured to enter the passageway and formed with bearing surfaces (37,38) which, in use, are exposed through the end openings of the barrel to engage the lock case. The aperture in each side of the lock case (1, 24) carrying the barrel is formed with a tab (31) which projects into the circumferential end opening of the barrel to prevent location of the barrel in its normal position biased by a spring (21). Insertion of the correct key (32) causes key end (39) to effect release of the barrel from the tab (31) by moving the barrel ends into a circular part of the aperture so that it can then be rotated by the key.

Description

LOCKS AND KEYS The present invention relates to lever locks and keys therefor.

By "lever locks" we mean locks of the well-known kind in which the keyrecognition mechanism comprises a plurality of pivoted or slidable tumblers or detainers (termed "levers") each having a surface usually of arcuate form (termed the "belly"), which is swept by a respective step of a billed key when the latter is turned in the lock, whereby to shift the levers to selected relative positions in which they collectively permit retraction of the bolt or other such locking member from its locking to its unlocking position. The keys for such locks typically comprise a bow (i.e. handle) portion joined by a shank to the bit. In the case of a so-called pin key, the operative end of the key has a portion formed as an extension of the shank (the "pin"), from which the bit proper extends in a radial direction. It is often the case that a lever lock includes a separate member which receives the pin of the key and turns with the key during locking and unlocking.

This turning member may have the function of a thrower which engages the bolt to extend or retract the same while the key bit keeps the levers lifted. Alternatively or additionally it may comprise a curtain member the purpose of which is to block access through the leg portion of the keyhole whenever it is turned away from the key-insertion position, as an antimanipulation measure. In any case this turning member typically comprises a part-cylindrical barrel portion journalled at each end in the lock casing, having an internal passageway to receive the pin of the key and a longitudinal slot opening from this passageway from which the key bit extends to contact the levers.

In our United Kingdom Patent Specification No. 2293409 there is disclosed a lever lock having a turning member which comprises a barrel borne at at least one end portion in the casing of the lock; the barrel having a longitudinal passageway to receive the pin of a key; the passageway opening through a longitudinal slot in the direction of the bit of a key, said slot opening through at least one end portion of the barrel; the passageway also opening through an end portion of the barrel at at least one circumferential location angularly displaced from said slot; and a key for the lock, the pin of which is configured at at least one end portion with at least one part-circumferential bearing surface which, when the key is fully inserted in the turning member, is adapted to be exposed through a said circumferential opening of the passageway to form part of a journal bearing with the lock casing as the key is turned. An advantage of such an arrangement is that notwithstanding the presence of the turning member the key is borne, at least in part, directly by the lock casing as it is turned, and thus avoids problems which can arise in conventional lever locks from tilting of the key due to the build-up of manufacturing tolerances in the fit of the key within the barrel of the turning member and the fit of that barrel within the lock casing. By appropriate configuration of the passageway in the barrel and its relationship with the key bearing surfaces of the lock casing this also provides a significant impediment to unauthorised key duplication; that is to say a person without access to appropriately configured keyblanks issued under the authority of the lock manufacturer will find it difficult if not impossible to cut a key to pass from a standard-form lever key blank.

The present invention seeks to enhance the security of lever locks by requiring that the key performs an additional function in relation to a turning member before the latter can be turned, and this too has advantages in impeding unauthorised key duplication. In one embodiment it comprises a modification of the lock and key described in our aforesaid patent specification, although compliance with that invention is not an essential feature of the present invention.

In one aspect the present invention accordingly provides, in combination, a lever lock having a turning member which comprises a barrel located at respective opposite end portions thereof in a casing of the lock; the barrel having a longitudinal passageway to receive a pin of a key; the passageway opening through a longitudinal slot in the direction of a bit of a key, said slot opening through at least one end portion of the barrel; the passageway also opening through an end portion of the barrel at at least one circumferential location angularly displaced from said slot; the turning member normally being biased to a first position in which it engages with the lock casing at at least one of said end portions whereby to block turning thereof; and a key for the lock, which key is configurated to engage with a portion of the lock casing and/or the barrel as it is inserted into said passageway, whereby to shift the turning member to a second position in which it is free to be turned by the key, the pin of the key being configurated at at least one end portion with at least one partcircumferential bearing surface which, when the key is fully inserted in the turning member, is adapted to be exposed through a said circumferential opening of the passageway to form part of a journal bearing with the lock casing as the key is turned.

In a preferred embodiment said passageway opens through said end portions at respective circumferential locations each angularly displaced from said slot, and the pin of the key is configured with partcircumferential bearing surfaces which, when the key is fully inserted in the turning member, are adapted to be exposed through said circumferential openings respectively of the passageway, each to form part of a journal bearing with the lock casing as the key is turned; in said first position of the turning member a portion of the lock casing intruding into each circumferential opening to block turning of the turning member as aforesaid; and wherein each part-circumferential bearing surface of the key pin is adapted to engage said intruding portion of the lock casing to hold the turning member in its said second position when the key is fully inserted.

The invention also resides per se in a lock for use in the above-defined combination, in a turning member for use in such a lock, in a key for use in such a combination, in a blank for such a key, and in a method of operating such a lock with such a key.

The invention will now be more particularly described, by way of example, with reference to the accompanying drawings, in which: Figure 1 illustrates the mechanism of one embodiment of a lever lock in accordance with the intention; Figure 2 is a rear view of the thrower incorporated in the lock of Figure 1; Figure 3 is a section on the line Ill-Ill through the thrower of Figure 2 showing also its mounting in the lock casing, in the absence of a key; Figure 4 is a section on the line IV-IV through the thrower of Figure 3; Figure 5 is a section on the line V-V of Figure 3 through part of the lock casing and thrower, in the absence of a key; Figure 6 is a side elevation of a blank for a key to be used with the lock of Figure 1; Figure 7 is a section similar to Figure 5 through part of the lock casing and thrower, with the key fully inserted; Figure 8 is a side elevation of a modified blank for a key to be used with the lock of Figure 1; Figures 9A - 9C are a side elevation, a scrap end view and a section on line 9-9 respectively, of a further form of a blank for a key to be used with the lock of Figure 1; Figures 10A - 10C and 1 1A - 11C are views equivalent to Figures 9A 9C of two further forms of key blank respectively, and Figures 1 2A - 1 2B and 1 3A - 1 3B are views equivalent to Figures 9A and 9B respectively of two still further forms of key blank.

Referring to Figure 1, this illustrates the mechanism of a lever lock in accordance with a preferred embodiment of the invention. It comprises a casing of which the main part is formed by a plate 1 having turned-up edges 2 and a attached forend 3, and which is normally closed by a platelike cap located over the ends of posts 4 upstanding from the plate 1 and fixed by screws passing into threaded bosses 5 likewise upstanding from the plate 1, the cap being removed in Figure 1 for ease of illustration. A deadbolt 6 is borne for extension and retraction between locking and unlocking positions, having a head portion 7 guided through the forend 3 and a tail portion 8 guided by a track 9 formed in the plate 1. A pack of, say, five levers 10 are pivoted on a pin 11 upstanding from the plate 1 and are biased in the anticlockwise sense (as viewed) by respective leaf springs 12. Each lever 10 is formed with a pair of pockets 1 3A/1 3B separated by a respective gate 14 and in the illustrated locking condition a stump 15 upstanding from the bolt tail 8 is trapped in the forward pockets 1 3A of the levers, thereby blocking retraction of the bolt. The lock also comprises a thrower 17 borne in the casing in a manner to be more particularly described hereinafter.

In order to retract the bolt 6 from the illustrated position a correct key is inserted into the thrower 17 and given one complete turn in the clockwise sense (as viewed). As the key turns, respective steps on its bit sweep the bellies 16 of respective levers to lift the same against the bias of their springs 12, by the correct heights to align their respective gates 14 with the bolt stump 15. The key also of course turns the thrower 17, which has on its rear side a rib 18 to engage in a talon form 19 in the bolt tail 8.

While the levers 10 remain lifted by the turning key the thrower rib 18 retracts the bolt 6 so that its stump 15 passes through the aligned lever gates 14 from pockets 1 3A to pockets 1 3B. As the key completes its revolution and disengages from the lever bellies 16 the levers are allowed to fall once more, to leave the stump 15 trapped in the rearward pockets 1 3B and the bolt consequently blocked against extension. Subsequent extension of the bolt 6 is of course the reverse of this action, with the key turning anticlockwise (as viewed).

The thrower 17 also incorporates a curtain 20 which blocks access through the leg portion of the keyhole provided in the plate 1 whenever it is turned away from the illustrated key-insertion position. A detent spring 21 also acts on the curtain 20 so as normally to keep the whole thrower 17 in the key-insertion position.

Referring also to Figures 2-4, the thrower 17 comprises in addition to the rib 18 and the curtain 20 a barrel portion 22. The external profile of the barrel 22 is generally cylindrical, with the end portions of the barrel being of reduced external diameter as indicated at 23 where they are located respectively in the plate 1 and the cap 24 (Figure 3) of the lock casing. As shown in Figure 3, in this embodiment the lock casing is of laminated form, at least in the vicinity of the thrower and levers, with hardened antidrill plates 1' and 24' being fixed externally to the plate 1 and cap 24 respectively. The interior of the barrel 22 is formed as a flat-sided passageway of stepped width, thus having a narrower section 25A and a wider section 25B. At each of the reduced-diameter end portions of the barrel the passageway sections 25A and 25B each open through the cylindrical wall of the barrel, at diametrically opposed locations. The passageway section 25A also opens through a slot 26 throughout the length of he barrel, and joins a slot 26A through the curtain 20. It will be observed that the wider passageway sections 25B is offset with respect to the rotational axis of the thrower in the direction away from the slot 26.

That is to say the centre of area (centroid) of the section 25B is located above the rotational axis in the sense as viewed in Figure 2.

The form of the aperture in the cap 24 wherein the respective end portion 23 of the barrel is located is shown in Figure 5, the corresponding aperture in the plate 1 being of identical form. In addition to a leg portion 27 to pass the key bit on insertion of the key it comprises a portion 28 within which the respective barrel end 23 turns when locking and unlocking.

The margins of portion 28 are in part defined by two lower arcuate surfaces 29 and an upper arcuate surface 30, all on a common circumference sized to accommodate the turning barrel end 23. Above the surfaces 29, however, the aperture is opened out to leave a tab 31 of casing material which presents the surface 30. This configuration of the aperture portion 28 is such that the thrower 17 can adopt a position as shown in Figure 5 in which the tab 31 intrudes into the circumferential opening of the passageway section 25B, the effect of the detent spring 21 being to bias the thrower upwardly into this position, as schematically indicated in Figure 3. Thus, and as also shown in Figure 3, in the normal condition of the lock, with no key inserted into the thrower 17, the tab 31 intrudes into the passageway section 25B at each end of the barrel 22 and thereby blocks the thrower from turning.

The form of a blank from which keys for the illustrated lock can be cut is illustrated in Figure 6, and the key is also seen in section in Figure 7.

The blank 32 has conventional bow 33, shank 34, collar 34A and bit 35 portions, but differs from a conventional blank in terms of the configuration of its pin region. The main part of the pin is formed as a flatsided, stepped-width extension of the shank 34, thus having a narrower section 36A dimensioned to fit within section 25A of the thrower passageway surmounted by a wider section 36B dimensioned to fit within section 25B of the thrower passageway, the pin section 36A joining and being of the same width as the bit portion 35. The upper surface of section 36B is formed as a partsylindrical bearing surface 37 and the lower surface of section 36A, to each side of the bit 35, is formed as partcylindrical bearing surfaces 38 on the same circumference as the surface 37 but over a shorter arc. A lead-in or nose portion 39 also extends forwardly from pin section 36B, having tapered/chamfered upper and lower surfaces 39A, 39B.

In use of a key cut from a blank 32, its operative end is inserted into the thrower 17, from either side of the lock, the thrower initially being in its blocked position as shown in Figures 3 and S. During the first part of the key insertion its upper and lower tapered nose surfaces 39A and 39B engage respectively the surface 30 of the tab 31 on the plate 1 or cap 24 (depending from which side the key is being inserted) and ledges 40 which are formed at the junction of the barrel passageway sections 25A, 25B. The effect of this, as the key continues to be inserted, is to cam the thrower down from the position of Figure 5 to the position of Figure 7, in which it is freed to rotate. The key pin section 36B is received in the barrel passageway section 25B with its part-circumferential bearing surface in contact with the surfaces 30 at each end under the bias of the spring 21.

The key pin section 36A is received in the barrel passageway section 25A and the bit 35 extends through the slots 26, 26A. The depth of insertion of the key is determined by the abutment of the shoulder 41 at the end of the collar 34A with the respective barrel end 23, and this correctly positions the bit 35 axially in relation to the levers 10 and also locates the bearing surfaces 37, 38 at each end of the key pin in the reduced-diameter end portions of the barrel.

As the key is turned, the bearing surfaces 37, 38 of the key pin can bear directly against the surfaces 29, 30 of the plate 1 and cap 24 to minimise the risk of tilting of the key irrespective of the fit of the thrower 17 in the lock casing, as in GB2293409. In this respect the most critical part of the revolution of the key is of course where its bit 35 contacts the lever bellies 16 and lifts the levers to their full heights to align their gates 14 with the bolt stump 15, which occurs as the key reaches a position displaced approximately 1600 clockwise from that illustrated in Figure 7. In this position the reaction force from the lever springs 12 is acting down upon the key bit to press the bearing surface 37 of the key pin firmly against the surfaces 29 of the plate 1 and cap 24, and it is this relationship which essentially determines the accuracy of the lever lifts for a given key stepping, rather than the fit of the key in the thrower and the fit of the thrower in the lock casing. The illustrated cross-sectional shape of the key pin 36A/36B and barrel passageway 25A/25B is such as to permit the key to take up any slack in its fit within the passageway by shifting slightly if necessary, under the reaction force from the lever springs, in the direction to expose the surface 37 through the respective passageway openings.

Relieving the upper surface of the barrel passageway as indicated at 42 in Figures 2 and 3 is useful for ensuring that there is no interference with this freedom from contact between the upper surface of the key pin and the facing internal surface of the passageway section 25B. Due to the greater width of the pin portion 36B than the keyhole leg 27, the surface 37 can bridge the circumferential gaps between the surfaces 29, so that the key remains properly supported by the lock casing as it passes through the 1800 rotated position.

As the key completes its revolution, in either direction, the curtain 20 encounters the spring 21, so that on withdrawal of the key the thrower is once more biased into its blocked position of Figure 5. The shape of the curtain is, however, such that the thrower is relieved of the action of the spring 21 during the parts of the key revolution in which it is in contact with the levers and bolt.

An advantage of the above described lock, in terms of unauthorised key duplication, is that even with a correctly cut bit a key will not operate the lock unless it also has the correct pin form both to free the thrower for rotation and to bear against the lock casing as it is turned. It is particularly preferred that the effective height of the passageway section 25B, that is to say the dimension between the ledges 40 and the surface 30 when the thrower is freed to rotate, is greater than the width of that section. In this way it is ensured that any standard-form lever key with a circular pin sized to fit within the width of section 25B will not have a sufficient diameter to cam down the thrower to a position in which it can turn.

Figure 8 illustrates a modified form of the key blank 32. In this case the upper surface of the pin is relieved to leave two separate bearing surfaces 37A and 37B at each end of section 36B, an inclined surface 43 similar to surface 39A being provided as a lead-in to the rearmost bearing surface 37B and another inclined surface 44 being provided behind the leading bearing surface 37A. In this case, when the key is first inserted into the barrel passageway the thrower will be depressed by the action of the tapered nose portion as before but after the first bearing surface 37A has passed the first tab 31 the thrower will resile towards its blocked position until both surfaces 39A and 43 encounter respective tabs 31 on each side of the lock to depress the thrower once more. On withdrawal of the key the thrower will likewise resile when the bearing surfaces 37A and 37B have cleared the tabs 31 but will be depressed as the surface 44 encounters the final tab 31 on withdrawal before finally resiling to the Figure 5 position when the key is completely removed.

In another modification of the illustrated lock and key blank it can be arranged that bearing support for the key is provided additionally or instead by the engagement of key surfaces with the anti-drilling plate(s) 1', 24' of the lock casing at one or both sides of the lock.

Figures 9A - 9C show a further alternative form of key blank, this being denoted by numeral 45. It differs from key blank 32 in Fig. 6 by having the respective upper and lowered tapered end surfaces of its nose portion of different lengths and angles. As shown, the lower surface 46 is short and angled sharply downwards to join the under surfaces 47 of section 36B, which surfaces 47 here extend beyond the end of the bearing surface 38 at the end of the key blank. The upper tapered surface 48 is however longer and less sharply angled upwards, to join bearing surface 37 at the axial position corresponding to the end of the surface 38. The crosssectional shape of the pin and bit, shown in Figure 9C, is substantially the same as for the key blank 32 of Figure 7.

Figures 1 0A - 10C show a further alternative form of key blank, where the taper is substantially on the lower end surface, this surface 49 terminating just ahead of the end of the bearing surface 38. The cross-sectional shape of the pin and bit, shown in Figure 10C, is similar to that of Figure 14 in our Patent N". 2293409. With Figures 1 1A - 11C, the key blank is modified from that of Figures 1 0A - 10C, by having its cross-sectional shape of stepped form, similar to that of Figure 15 in our Patent N".

2293409.

The key blank of Figures 1 2A and 1 2B is similar to that of Figures 9A - 9C, but with the respective tapers reversed, i.e. with the longer, more angled taper on the underside. Finally for the key blank of Figures 1 3A and 13B, the main modification is that the opposite sides of the section 36B are fluted to effect warding. Accordingly the corresponding shape of section 25B of the thrower passageway would be complementarily shaped, rather than being substantially flat-sided, as with the other key blank sections described.

In fact flat-sided keys are not essential and various other shapes could be used. If the thrower is open along the whole of its upper surface circular section key pins could be used.

It will be understood that in its normally biased position the rotational centre of the thrower is spaced above the centre of the circle of which the arcuate surfaces 29 and 30 are part. The insertion of the correct key moves the thrower downwardly, as described, so that these centres coincide. This amount of movement is 'effected' by the taper on the leadin or nose-portion of the key, and brings the ledges 40 to a level to be engaged by the respective undersurfaces of section 36B at opposite sides of the key bit. Accordingly the reduced depth tapered section leads to a section of the key where the distance between the upper and lower 'surfaces' of section 36B is of full depth, and thus fills portion 28.

It will also be understood that the key can form a journal bearing with the lock casing at one end only. Similarly there can be a tab 31, which normally prevents thrower rotation, at one end only, and thus the thrower need have an upper opening from passageway section 25B at one of its ends only. The downwards movement of the thrower by the nose portion of the key upon key insertion can be effected by the upper taper engaging the lock casing, the lower taper engaging the thrower, or, as described, by both actions.

As described and illustrated, all the keys of the invention have an end portion extending beyond the key bit or blade, and beyond the bearing surface of the key if it is provided with one at the side of the key bit remote from the key bow, this end portion having a taper to lead the key into the lock and depress the follower.

Claims (27)

1. In combination: a lever lock having a turning member which comprises a barrel located at respective opposite end portions thereof in a casing of the lock; the barrel having a longitudinal passageway to receive a pin of a key; the passageway opening through a longitudinal slot in the direction of a bit of a key, said slot opening through at least one end portion of the barrel; the passageway also opening through an end portion of the barrel at at least one circumferential location angularly displaced from said slot; the turning member normally being biased to a first position in which it engages with the lock casing at at least one of said end portions whereby to block turning thereof; and a key for the lock, which key is configured to engage with a portion of the lock casing and/or the barrel as it is inserted into said passageway, whereby to shift the turning member to a second position in which it is free to be turned by the key, the pin of the key being configured at at least one end portion with at least one part-circumferential bearing surface which, when the key is fully inserted in the turning member, is adapted to be exposed through a said circumferential opening of the passageway to form part of a journal bearing with the lock casing as the key is turned.

2. A combination according to Claim 1, wherein said passageway opens through said end portions at respective circumferential locations each angularly displaced from said slot, and the pin of the key is configured with part-circumferential bearing surfaces which, when the key is fully inserted in the turning member, are adapted to be exposed through said circumferential openings respectively of the passageway, each to form part of a journal bearing with the lock casing as the key is turned, in said first position of the turning member a portion of the lock casing intruding into each circumferential opening to block turning of the turning member as aforesaid, and wherein each part-circumferential bearing surface of the key pin is adapted to engage said intruding portion of the lock casing to hold the turning member in its second position when the key is fully inserted.

3. A combination as claimed in Claim 2, wherein said passageway opens through said end portions at respective circumferential locations which are diametrically opposed to said slot and the pin of the key is configured at each of its said end portions with two diametrically opposed part-circumferential bearing surfaces adapted to be exposed through said diametrically opposed circumferential openings at each of said end portions.

4. A combination as claimed in Claim 1, wherein the turning member engages with the lock casing at one of said end portions of the turning member by means of an aperture in the lock case being formed with a tab which locates in a said circumferential opening of the passageway of the turning member.

5. A combination as claimed in Claim 4, wherein the aperture in the lock case comprises a leg portion to pass the key bit on insertion of the key, and a circular portion within which the turning member turns during locking and unlocking, the circular portion including a surface formed on the tab.

6. A combination as claimed in Claim 5, wherein said circular portion includes two arcuate side surfaces extending from the leg portion, which side surfaces, with said surface of the tab, are on a common circumference sized to accommodate the turning member, the circular portion being opened out at the respective ends of the side surfaces remote from the leg portion to define said tab.

7. A combination as claimed in any one of the preceding Claims wherein the turning member incorporates a curtain upon which biasing means acts so as normally to bias said turning member to its first position.

8. A combination as claimed in any one of the preceding Claims, wherein the key has a forward lead-in portion extending forwardly from its pin section, which lead in-portion incorporates a tapered surface to engage the lock casing and/or the turning member to shift the turning member to its second position upon key insertion.

9. A combination as claimed in Claim 8, wherein the tapered section terminates at or in advance of said bearing surface(s) at the forward end of the key.

10. A combination as claimed in any one of claims 1 to 9, wherein the cross-section of the passageway comprises a first portion opening from said slot, and a second portion joining said first portion and having a width greater than said first portion, the effective height of the second portion being greater than its width.

11. A lock for use in a combination as claimed in any one of the preceding Claims.

12. A key for use in a combination as claimed in any one of the preceding Claims.

13. A key for a lever lock, the key comprising a bow, a shank, a pin and a bit extending below the pin, the pin extending longitudinally beyond opposite ends of the bit to define end portions thereof, an upper surface of an end portion of the pin being formed as a part-circumferential bearing surface, adapted, in use, to be exposed through an opening in the barrel of a turning member to form part of a journal bearing with the casing of the lock as the key is turned, a forward end of the key defining a tapered surface which, upon insertion of the key into the lock in use, engages with the lock casing and/or the barrel of the turning member to shift the turning member from a first position, to which it is normally biased to engage the lock casing to block turning thereof, to a second position, in which it is free to be turned by the key upon full insertion thereof.

14. A key as claimed in Claim 13, wherein the lower surface at said an end portion of the pin is also formed as a part-circumferential bearing surface adapted, in use, to be exposed through a respective opening in the barrel of a turning member to form part of a journal bearing with the casing of the lock as the key is turned.

15. A key as claimed in Claim 13 or Claim 14, wherein said tapered surface is provided on an upper surface of a forward end of the key.

16. A key as claimed in any one of Claims 13 to 15, wherein said or a further tapered surface is provided on a lower surface of a forward end of the key.

17. A key as claimed in Claim 15 or Claim 16, wherein the tapered surface extends in a direction rearwardly from the forward end of the key to terminate at an end of said bit.

18. A key as claimed in Claim 15 or Claim 16, wherein the tapered surface extends in a direction rearwardly from the forward end of the key to terminate at said bearing surface.

19. A key as claimed in Claim 15 or Claim 16, wherein the tapered surface extends in a direction rearwardly from the forward end of the key to terminate in advance of the key bit, without a bearing surface therebetween.

20. A key as claimed in any one of Claims 13 to 19, wherein at least one side of the pin is fluted.

21. A key as claimed in Claim 14, wherein the upper bearing surface is of the same radius as, but extends over a longer arc than, said lower bearing surface.

22. A key as claimed in any one of Claims 13 to 21, wherein said bearing surface(s) is or are provided at both end portions of the pin.

23 A key as claimed in any one of claims 13 to 22, wherein the cross-section of at least the end portions of the pin comprise a first, lower portion and a second portion above the first portion having a width greater than the first portion, said width of the second portion being less than its height.

24. A key substantially as hereinbefore described, with reference to, and as shown in Figure 6, or Figure 8, or Figures 9A - 9C, or Figures 10A - 10C, or Figures 11A- 11C, or Figures 12A- 12B, or Figures 13A- 13B, of the accompanying drawings.

25. A blank for a key as claimed in any one of Claims 12 to 23.

26. A lock substantially as hereinbefore described, with reference to, and as shown in Figures 1 to 5 and 7 of the accompanying drawings.

27. A turning member for use in a combination or lock as claimed in any one of Claims 1 to 11 or Claim 26.