Lock

Abstract

 A lock comprising a frame (1), a dead bolt (41) slidably mounted on the frame (1) between a retracted and a projecting position, a key actuated cylinder (13) provided with a rotary driving bit (14) arranged to move the dead bolt (41), and locking means (66) for locking the dead bolt (41) in its retracted and projecting positions. The rotary driving bit (14) is arranged to move the dead bolt (41) through the intermediary of a dead bolt lever (58). This dead bolt lever is pivoted about a pivot (59) with respect to the frame (1) and engages the dead bolt (41) on a first distance from said pivot (59) whilst said rotary bit (14) engages the dead bolt lever (58) on a distance (D2) from said pivot smaller than said first distance (D1). In this way, the stroke of the dead bolt is increased for one turn of the driving bit (14).

Description

[0001] The present invention relates to a lock, in particular a safety lock for outside gates, doors or fences, comprising a frame, a dead bolt slidably mounted in a predetermined direction on the frame between a retracted and a projecting position, a key actuated cylinder provided with a rotary driving bit arranged to move the dead bolt from its retracted to its projecting position and vice versa, and locking means for locking the dead bolt in its retracted and projecting positions.

[0002] Such a lock is disclosed in WO 98/37295 in the name of the present applicant. The lock disclosed in this international application is mounted laterally against a tubular profile of the gate or fence wherein holes are made so that the dead and latch bolt can extend right through this profile. The dead bolt is provided on its lower side with three different notches wherein the rotary driving bit engages this bolt to move it between its retracted and projecting positions. By selecting one of the three notches, the distance over which the dead bolt projects out of the lock can be adjusted in accordance with the diameter of the tubular profile.

[0003] A disadvantage of the lock disclosed in WO 98/37295 is however that the stroke of the dead lock, or in other words the distance over which the dead lock is moved when going from its projecting position to its retracted position or vice versa, is determined by the length of the rotary driving bit of the cylinder and is thus limited to a certain maximum stroke. With a so-called Euro profile cylinder according to the standard DIN V 18 254/07.91 a stroke of about 15 mm can thus be achieved. In indoor applications, such a stroke may be enough but in certain outdoor applications, a larger stroke is to be preferred. Indeed, in case of gates or fences, the lock catcher is usually fixed to a pole placed in a hole in the ground. Although this hole is usually filled with concrete, the pole may move somewhat, especially after some time under the influence of frost or moisture or when a force is exerted thereon for example by a burglar who tries to force the pole away from the lock. It will be clear that the larger the stroke of the dead bolt, the more difficult it will be to withdraw the dead bolt from the lock catcher by removing the pole from the gate or fence.

[0004] In order to achieve a larger stroke, it is already known to provide a two-turn lock, which requires two turns of the key in order to project the dead bolt over its maximum distance out of the lock. However, turning the key two times is a cumbersome operation so that in practice, the key will often only be turned once.

[0005] An object of the present invention is therefore to provide a lock with a dead bolt having an increased stroke for one single turn of the key.

[0006] To this end, the lock according to the invention is characterised in that said rotary driving bit is arranged to move the dead bolt through the intermediary of a dead bolt lever, which dead bolt lever is pivoted about a pivot with respect to the frame and engages the dead bolt on a first distance from said pivot to move this dead bolt from its retracted to its projecting position or vice versa upon rotation of the dead bolt lever around said pivot, said rotary bit engaging the dead bolt lever on a distance from said pivot smaller than said first distance.

[0007] In the lock according to the invention, the rotational motion to the rotary driving bit of the cylinder is converted into the translational motion of the dead bolt through the intermediary of the dead bolt lever. Since the driving bit engages the dead bolt lever on a smaller distance from the pivot of this lever than the distance between this pivot and the location where the lever engages the dead bolt, a lever effect is obtained resulting in a larger displacement of the dead bolt. However, this is not the only possible stroke increasing effect. Indeed, by the rotational motion of the dead bolt lever around its pivot, the part thereof where the driving bit of the cylinder engages the lever does not follow a straight but on the contrary a curved line. As a result of this rotational motion, the driving bit may engage the dead bolt lever over a longer part of its rotational motion resulting also in an increased stroke of the dead bolt.

[0008] In a preferred embodiment of the lock according to the invention, the rotary bit engages the dead bolt lever at a first location situated between the dead bolt and said pivot. In a further preferred embodiment, the cylinder is even entirely situated between the dead bolt and said pivot.

[0009] An advantage of these embodiments is that they allow a compact construction of the lock. In case the cylinder is entirely situated between the dead bolt and the pivot of the dead bolt lever, the cylinder and this pivot can be arranged in one single plane perpendicular to the axis of the dead bolt in order to obtain the most practical actuation of the dead bolt.

[0010] In an advantageous embodiment of the lock according to the invention, the lock comprises a latch bolt slidably mounted on the frame between a projecting and a retracted position, a spring arranged to urge the latch bolt to its projecting position, a second turn lever pivotally mounted on the frame and arranged to move the latch bolt from its projecting to its retracted position upon rotation thereof, and a second turn pusher arranged to be actuated by said rotary driving bit and connected to the second turn lever to rotate this second turn lever upon actuation by said driving bit. In this embodiment, the lock is characterised in that said second turn pusher is slidably connected to an arm of said dead bolt lever at a second location situated between the dead bolt and said pivot.

[0011] In locks provided with a second turn lever for withdrawing the latch bolt upon a second rotation of the key, the second turn pusher is usually connected to the dead bolt to move into and out of engagement of the rotary driving bit of the cylinder. A disadvantage thereof is that in case the dead bolt has a large stroke, quite a lot of space has to be provided in the lock for the movement of the pusher. A further disadvantage is that it does not allow for example to change the position of the dead lock in the lock as disclosed for example in WO 98/37295 in order to adjust the distance over which the dead bolt projects out of the lock. These disadvantages have now been obviated in the present embodiment by connecting the pusher to the dead bolt lever between the pivot thereof and the dead bolt. In this way, the pusher moves over a smaller distance than the dead bolt and requires thus less space. Moreover, the position of the dead bolt in the lock can be adjusted without influencing the movements of the second turn pusher.

[0012] Further advantages and particularities of the invention will become apparent from the following description of some particular embodiments of the lock according to the invention. This description is only given by way of illustrative example and is not intended to limit the scope of the invention as defined by the annexed claims. The reference numerals used in the description refer to the drawings wherein:

Figure 1 shows an exploded view of a lock according to a first embodiment of the invention, both handles being omitted for clarity's sake;

Figure 2 shows a side elevational view of the lock according to Figure 1, the cover box of the lock being removed and dead and latch bolts being in their projecting position;

Figure 3 is a view analogous to the view of Figure 2 but with the dead lock in its retracted position;

Figure 4 is a view analogous to the view of Figure 3 but with the dead lock adjusted to project over a smaller distance out of the lock and with the latch also in its retracted position and adjusted to project over a smaller distance out of the lock;

Figure 5a and 5b are exploded views of a dead lock and respectively a latch bolt of a second embodiment of the invention; and

Figure 6 is a view analogous to the view of Figure 2 but showing the lock according to the second embodiment.

[0013] The lock shown in the drawings is a lock provided to be mounted against a profile, in particular a tubular profile, of a gate, fence, door, etc. The profile is provided with holes so that both the latch and the dead bolt can project there through. When mention is made of a retracted position of the latch or dead bolt, this consequently does not mean that the bolt is retracted within the lock but that it is retracted within the tubular profile or that it extends over a small distance out of this profile. In its extended position, the bolt then extends over a larger distance out of the tubular profile, the difference between these two distances being called the stroke of the bolt.

[0014] The illustrated lock comprises a frame 1 composed of a cover box 2, a front cover plate 3 for closing the box 2 and a base plate 4 arranged within the closed box 2. The base plate 4 has on its front side an upstanding edge 5 and on its back side two upstanding edge portions 6, 7. The cover box 2 has such dimensions that the base plate 4 can be slid completely therein, more particularly through the substantially rectangular front opening 8 of the box 2, even the upstanding edge 5.

[0015] The cover plate 3 is somewhat larger than the front opening 8 so that it engages against the peripheral edge thereof. By means of screws 9, which pass through openings in the upstanding edge 5 of the base plate 4 and in the cover plate 3 into treaded holes 10 in the cover box 2, these different elements are assembled together. The screws 9, and spacers 11 applied thereover, are further used to fix the lock laterally to the tubular profile of the gate.

[0016] The cover box 2 is provided with two aligned openings 12 through which a cylinder 13 can be inserted in the lock, in particular a so-called Euro-cylinder corresponding to the standard DIN V18254/07.91. This key actuated cylinder 13 comprises a rotary driving bit 14 which rotates around a central axis of the cylinder to actuate the lock as described hereinafter. The cylinder 13 is fixed in the lock by means of a screw 15 passing through little holes made in the cover plate 3 and in the upstanding edge 5 of the base plate 4. The cover box 2 is further provided with two additional aligned openings 16 wherein the door handles can be mounted. These handles as well as their square shaft are known per se and have not been shown in Figure 1, only the door handle rings 17 have been illustrated.

[0017] The illustrated lock further comprises a latch bolt 18 which is slidably mounted in the direction of arrow 19 on the frame 1 of the lock, more particularly within an opening 20 in the upstanding edge portion 6, an opening 21 in the upstanding edge 5 and within an opening 22 in the cover plate 3. The latch bolt can thus move between a projecting position shown in Figures 2 and 3 and a retracted position shown in Figure 4. A compression spring 23 is applied over the latch bolt 18 to urge this bolt to its projecting position. For bringing the latch bolt 18 by means of the handles to its retracted position to open the gate, the rectangular shaft of the handles is inserted in a corresponding hole in a follower 24. This follower 24 is provided in its turn with a latch bolt lever 25 which follows the rotations of the handles and which engages the latch bolt 18 against the action of a main spring 26 to open this latch bolt. The main spring 26 serves to push the latch bolt lever 25 and thus the follower 24 and the handles to their initial rest positions.

[0018] In contract to the usual latch bolts, the latch bolt 18 of the lock illustrated in the drawings is made of steel, more particularly of stainless steel. Compared to the usual copper-zinc alloys, steel is much stronger and more weather resistant but is much more difficult to be shaped in the usual way by milling etc. As will become apparent hereinafter, the latch bolt has to have indeed a quite complex shape, especially in order to allow to adjust the length over which it projects out of the lock.

[0019] It has now been found that such a shape can be obtained with minimal milling operations by making latch bolt 18 of two separate parts, namely of a hollow rod part 27 which extends at least partially within the lock and a more solid bolt part 28 which is arranged to project out of the lock into a lock catcher. In the embodiment illustrated in the drawings, the hollow rod part 27 is composed of a U-shaped portion 29 and a cylindrical portion 30. It can simply be pressed out of sheet steel with minimal milling operations. The bolt part 28, on the contrary, is made from a solid stainless steel cylindrical rod, wherein an axial passageway is drilled. On one side, it has an oblique front face and, on the other side, it has a recessed portion 31 by means of which the bolt part 28 can be removably mounted in the hollow rod part 27. For fixing the bolt part 28, a screw 32 is provided which can be screwed through an opening in the hollow rod part 27 into a treaded hole 34 in the recessed portion 31 of the bolt part 28. Since this treaded hole 34 (but not the screw 32, except in the embodiment of Figure 5b) extends entirely through the recessed portion 31, the bolt part 28 can be mounted in two different positions, namely in a first position wherein the oblique front face is directed in a first direction and in a second position wherein the bolt part 28 is rotated axially over about 180°.

[0020] In order to allow an adjustment of the latch bolt, the U-shaped portion 29 is provided in the embodiment of Figures 1 to 4 with two opposite slots 35. Within the portion 29, slide means 36 are arranged which project through the slots 35 to form an abutment, on the one hand, for the compression spring 23 and, on the other hand, for the latch bolt lever 25 on one side and for a second turn lever 73 (which will be described hereinafter) on the other side. The slide means 36 are fixed with respect to the latch bolt 18 by means of a set screw 37 which is screwed in a treaded hole 38 in the slide means 36. The head of the set screw 37 is captured between an inner shoulder, formed at the transition between the U-shaped portion 29 and the cylindrical portion 30 of the latch bolt 18, and the back face of the bolt part 28. By rotating the screw 37, the position of the slide means 36 with respect to the latch bolt 18 can be adjusted continuously and thus the distance over which the latch bolt 18 projects out of the lock. In Figures 2 and 3, the latch bolt 18 projects over a maximum distance out of the lock, the minimum distance being indicated in dotted line, whilst in Figure 4 the latch bolt has been adjusted to an intermediate position. Access to the set screw 37 is provided through the axial passageway in the bolt part 28.

[0021] In the variant embodiment of the adjustable latch bolt shown in Figure 5b, the slots 35 are replaced by treaded holes 39 wherein a screw 40, forming an abutment for the compression spring 23 and the latch bolt and second turn levers 25 and 73, can be fixed. The different positions of the holes 39 correspond to different distances over which the latch bolt 18 projects out of the lock. In Figure 6, the latch bolt 18 projects over a minimum distance out of the lock, the maximum distance being indicated in dotted line. It will be clear that in this variant embodiment, the screw 40 could be replaced by another abutment means which can be fixed into the holes 39 in the latch bolt.

[0022] In addition to the latch bolt, the lock illustrated in the drawings also comprises a dead bolt 41. This dead bolt 41 is essentially made in the same way as the above described latch bolt 18. It is in particular also made of steel, preferably of stainless steel, and comprises a hollow rod part 42 extending at least partially in the lock and a bolt part 43 arranged to co-operate with the lock catcher. The hollow rod part 42 can simply be pressed out of sheet steel and comprises a U-shaped portion 44 and a cylindrical portion 45 wherein the bolt part 43 is fixed, more particularly by means of a recessed extremity 46 thereof.

[0023] In the U-shaped portion 44, slide means 47 are arranged which are guided in slots 48 in the dead bolt 43. The position of the slide means 47 with respect to the dead bolt 41 can be adjusted by means of a set screw 49 which is accessible through an axial passageway 50 in the bolt part 43 and which is screwed in a treaded hole 51 in the slide means 47. By means of this set screw 49, the distance over which the dead bolt 41 projects out of the lock can thus be continuously adjusted between the extreme positions indicated in Figures 2 to 4. In the variant embodiment of the dead bolt 41 illustrated in Figure 5a, the slots are replaced by treaded holes 52 wherein a screw 53 can be fixed. The two extreme positions of the dead bolt 41, which can thus be achieved, in addition to an intermediate position, are illustrated in Figure 6.

[0024] Just as the latch bolt 18, the dead bolt 41 is slidably mounted in the direction of a double arrow 54 on the frame 1 between a projecting position, illustrated in Figures 2, 3 and 6, and a retracted position, illustrated in Figure 4. The dead bolt 41 can more particularly slide in openings 55, 56 and 57 respectively in the upstanding edge portion 7 and the upstanding edge 5 of the frame 1 and in the cover plate 3.

[0025] In contrast to the latch bolt, the dead bolt 41 is not urged by a spring to its projecting position but is locked in both its retracted and projecting positions by means of locking means. In the illustrated embodiment, these locking means comprise a retaining plate 66 which is slidably mounted in the up- and downward direction according to arrow 67 on the frame 1. The plate 66 is provided with a slot 68, which form at both ends an upward notch 69. In its normal position, the plate 66 is urged downward by means of an end 80 of the main spring 26, which engages an upstanding edge 70 of the plate 66, so that the slide means 47 (or the screw 53 in the embodiment of Figure 5a) project into one of the notches 69 and thus lock the dead bolt in one of its extreme positions.

[0026] The movement of the dead bolt 41 between its two extreme positions is controlled by rotating the key in the cylinder 13, or in other words by the resulting rotation of the rotary driving bit 14. When rotating this bit 14, it first of all engages the bottom edge 71 of the retaining plate 66 so that this plate is lifted and the dead bolt is unlocked. According to the invention, the rotary driving bit 14 does not act directly upon the dead bolt 41 but instead through the intermediary of a dead bolt lever 58. This lever 58 is pivoted about a pivot 59, which fits into a hole 60 in the base plate 4. The free extremity of the lever 58, situated opposite the pivot 59, is provided with a slot 61. This free extremity extends within the U-shaped portion 44 of the dead bolt 41 so that the slide means 47, or the screws 53 in the embodiment of Figure 5a, extend through the slot 61 of the lever 58. In this way, the slide means 47, or the screw 53, form an abutment means which is engages by the dead bolt lever 58 when moving the dead bolt 41 from its projecting to its retracted position, or vice versa. When moving to its projecting position, the dead bolt lever 58 engages the abutment means 47 or 53 of the dead bolt more particularly in a first point 62 on the dead bolt and, when moving to its retracted position, in a second point 63. This is due to the clearance between the slot 61 and the abutment means 47 or 53. In the drawings, the middle point 64 situated centrally between these first and second points coincides with the central axis of the slide means 47 or the screw 53.

[0027] An essential feature of the lock according to the present invention is that the dead bolt lever 58 engages the dead bolt 41 on a first distance D1 from the pivot 59 whilst the dead bolt lever 58 itself is engaged by the rotary driving bit 14 of cylinder 13 on a second distance D2 from this pivot 59, smaller than said first distance D1. Both the first and second distances may vary somewhat between the different positions of the dead lock but, in each position, the second distance D2 should be smaller than the first distance D1. As a result thereof, the stroke of the dead bolt 41 is increased compared to prior art locks wherein the dead bolt 41 is directly engaged by the rotary driving bit 14 of the cylinder 13.

[0028] In a particular embodiment of the invention, the driving bit 14 could engage an arm of the dead bolt lever extending below the pivot 59. In the illustrated embodiment, the driving bit 14 engages the dead bolt lever 58 however at a location situated between the dead bolt 41 and the pivot 59, more particularly in a notch 65, so that a compact lock can be achieved and so that the driving bit 14 engages the dead bolt lever 41 over a longer distance due to the circular path followed by the arm of the dead bolt lever 41. Preferably, as shown in the Figures, the cylinder 13 itself is entirely situated between the dead bolt 41 and the pivot 59. In this way, the most preferred embodiment, illustrated in the Figures, can be achieved. In this embodiment, the pivot 59 is positioned in such a manner that the above described middle point 64, situated centrally between the two engagement points 62 and 63 with the abutment means 47 or 53 on the dead bolt 41, moves from one side of a plane α perpendicular to the movement direction 54 of the dead bolt 41 and passing through the pivot 59 to the opposite side of this plane α when the dead bolt 41 moves from its projecting position (illustrated in Figure 2) to its retracted position (illustrated in Figure 3) or vice versa. In this embodiment, a minimum length of the slot 61 in the dead bolt lever 58 is required to enable the transformation of the rotational movement of this lever 58 into the translational movement of the dead bolt 41. Moreover, a portion of the bottom of the U-shaped portion 44 is cut away so that the free extremity of the dead bolt lever 41 can project through this portion 44 of the dead bolt 41.

[0029] When comparing Figures 2 and 3, it can be seen that both when moving the dead bolt to its projecting position or to its retracted position, the points where the rotary bit 14 engages the notch 65 in the dead bolt lever 58 are lowered to a position lower than the top of the cylinder 13 as a result of the rotation around pivot 59 so that the rotary bit 14 can engage the notch 65 over a longer distance. As mentioned already hereabove, this effect contributes also to achieving a longer stroke of the dead bolt 41. To maximise this effect and the lever effect on the stroke of the dead bolt, the pivot 59 of the dead bolt lever 59 is preferably situated as close as possible to the bottom side of the cylinder 13. In this way the ratio between the first and second distances D1 and D2, and thus the lever effect, increases, and also the up- and downward movements of the notch 65 when rotating around the pivot 59. In the embodiment shown in the drawings, an increase of the stroke from about 15 mm for a conventional lock to about 25 mm (1 inch) has thus been achieved.

[0030] An additional advantage of the presence of the dead bolt lever 58 is that it can be used to move a second turn pusher 72 into and out of the path of the rotary driving bit 14. Such a second turn pusher 72 is connected to a second turn lever 73 arranged to move the latch bolt 18, against the action of the compression spring 23, from its projecting to its retracted position. The second turn lever 73 is more particularly rotatably applied over the follower 24 and covered by a washer 74. It has a lever arm 75 which engages the abutment means, i.e. the slide means 36 or the screw 40, on the latch bolt 18 and shows further a hole 76 wherein the free extremity 81 of the pusher 72, which is hook shaped, is applied. At its other free extremity, the pusher 72 is provided with a slot 77 by means of which it is slidably connected to an arm 78 of the dead bolt lever 58. This connection between the pusher 72 and the arm 78 of the dead bolt lever 58 is located between the dead bolt 41 and the pivot 59 of the dead bolt lever 58. This means that it is situated at a level below the dead bolt 41 but above the pivot 59. In this way, the movement of the pusher 72 in a direction parallel to the movement of the dead bolt 41 can be kept to a minimum, which is important to enable a compact lock especially in case of an increased stroke of the dead bolt as in the present invention. The movement of the pusher 72 has only to be so large that it is out of the path of the rotary driving bit 14 in the projecting position of the dead bolt 41 (illustrated in Figure 2) but comes into this path when the dead bolt moves, upon a first turn of the rotary bit 14, to its retracted position (illustrated in Figure 3). Upon a second turn of the rotary bit 14, this rotary bit 14 engages a hook shaped portion 79 of the pusher 72 and pushes this pusher 72 upwards, as shown in Figure 4, to rotate the second turn lever 73 and thus retract the latch bolt 18.

[0031] From the above description of a particular embodiment of the invention, it will be clear that many modifications can be applied thereto as to the shape, composition, etc. of the lock without departing from the scope of the invention as defined in the appended claims.

[0032] Instead of being formed by one piece, the slide means 47 could for example be composed of an elongated slide element, arranged within the U-shaped part of the dead bolt, and a screw screwed transversally into this element and extending through the slots 58.

Claims

1. A lock comprising

- a frame (1);

- a dead bolt (41) slidably mounted in a predetermined direction (54) on the frame (1) between a retracted and a projecting position;

- a key actuated cylinder (13) provided with a rotary driving bit (14) arranged to move the dead bolt (41) from its retracted to its projecting position and vice versa; and

- locking means (66) for locking the dead bolt (41) in its retracted and projecting positions,

characterised in that said rotary driving bit (14) is arranged to move the dead bolt (41) through the intermediary of a dead bolt lever (58), which dead bolt lever is pivoted about a pivot (59) with respect to the frame (1) and engages the dead bolt (41) on a first distance from said pivot (59) to move this dead bolt (41) from its retracted to its projecting position or vice versa upon rotation of the dead bolt lever (58) around said pivot (59), said rotary bit (14) engaging the dead bolt lever (58) on a distance (D2) from said pivot smaller than said first distance (D1).

2. A lock according to claim 1, characterised in that said rotary bit (14) engages the dead bolt lever (58) at a first location situated between the dead bolt (41) and said pivot (59).

3. A lock according to claim 1 or 2, characterised in that said cylinder (13) is entirely situated between the dead bolt (41) and said pivot (59).

4. A lock according to any one of the claims 1 to 3, characterised in that said dead bolt lever (58) engages the dead bolt (41) in a first point (62) on the dead bolt (41) when moving to its projecting position and in a second point (63) when moving to its retracted position, said pivot (59) being positioned in such a manner that a middle point (64) situated centrally between said first and second points (62,63) moves from one side of a plane (α) perpendicular to said predetermined direction (54) and passing through said pivot (59) to the opposite side of this perpendicular plane (α) when the dead bolt (41) moves from its retracted to its projecting position or vice versa.

5. A lock according to any one of the claims 1 to 4, comprising a latch bolt (18) slidably mounted on the frame (1) between a projecting and a retracted position, a spring (23) arranged to urge the latch bolt (18) to its projecting position, a second turn lever (73) pivotally mounted on the frame (1) and arranged to move the latch bolt (18) from its projecting to its retracted position upon rotation thereof, and a second turn pusher (72) arranged to be actuated by said rotary driving bit (14) and connected to the second turn lever (73) to rotate this second tum lever (73) upon actuation by said driving bit (14), characterised in that said second turn pusher (72) is slidably connected to an arm (78) of said dead bolt lever (58) at a second location situated between the dead bolt (41) and said pivot (59).

6. A lock according to any one of the claims 1 to 5, characterised in that said dead bolt lever (58) engages the dead bolt (41) through the intermediary of an abutment means (47,53) fixed with respect to the dead bolt (41), the dead bolt (41) showing different positions wherein the abutment means (47,53) can be fixed with respect thereto corresponding to different distances over which the dead lock (41) projects out of the lock in its projecting position.

7. A lock according to claim 6, characterised in that said abutment means comprise a screw (53), which can be screwed in said different positions to the dead bolt (41).

8. A lock according to claim 6, characterised in that said abutment means comprise a slide means (47) slidably fixed with respect to the dead bolt (41), the dead bolt (41) being provided with adjustment means (49,51) which are arranged to be actuated from the outside of the lock and to slide upon actuation the abutment means (47) between said different positions on the dead bolt (41).

9. A lock according to claim 8, characterised in that said adjustment means comprise a screw (49) arranged in an axial passageway (50) extending through the dead bolt (41) and ending in a front face of the projecting free extremity of the dead bolt (41), which screw (49) is screwed in a threaded hole (51) in the slide means (47) and can be actuated through said passageway (50) through the projecting extremity of the dead bolt (41).

10. A lock according to any one of the claims 1 to 9, characterised in that the dead bolt (41) is made of steel, in particular of stainless steel, and comprises two separate parts, namely a first hollow rod part (42) extending at least partially within the lock and a first bolt part (43) arranged to project out of the lock to co-operate with a lock catcher.

11. A lock according to any one of the claims 1 to 10, characterised in that the lock comprises a latch bolt (18) slidably mounted on the frame (1) between a projecting and a retracted position and a spring (23) arranged to urge the latch bolt (18) to its projecting position, the latch bolt (18) being made of steel, in particular of stainless steel, and comprises two separate parts, namely a second hollow rod part (27) extending at least partially within the lock and a second bolt part (28) arranged to project out of the lock to co-operate with a lock catcher.

12. A lock according to claim 11, characterised in that the second bolt part (28) shows an oblique front face and is removably mountable onto the second rod part (27) in a first position wherein the oblique front face is directed in a first direction and in a second position wherein the bolt part (28) is rotated axially over about 180° with respect to said first position.

13. A lock according to any one of the claims 10 to 12, characterised in that said first hollow rod part (42) and/or said second hollow rod part (27) is pressed out of sheet steel.

14. A lock according to claim 13, characterised in that said first hollow rod part (42) and/or said second hollow rod part (27) comprises, in cross-section, a U-shaped portion (44,29) and a cylindrical portion (45,30), said first (43) and/or said second bolt part (28) being fixed into the cylindrical portion (45,30).

Drawing