FR2577970A1 - Combination safety lock and method of opening the lock - Google Patents

Abstract

The lock comprises coding means 2, 3 and bolt means 6, 7 movable in translational motion over a predetermined return stroke L1 + L2 after the unscrambling of the coding means for the purpose of opening the lock. It is characterised by means 72 for stopping the bolt means 6, 7 in an intermediate position L1 of the return stroke after the unscrambling of the coding means and by means 8 for both preventing a return of the bolt means 6, 7, when the coding means 2, 3 are scrambled and the lock is completely closed, and allowing an end-of-stroke return L2 of the bolt means 6, 7 after a scrambling of the coding means when the bolt means are substantially in the intermediate position. In the intermediate position, the slight return of the bolt means does not make it possible to open the lock, with the result that a scrambling of the coding means is obligatory before any opening of the lock.

Description

COMBINATION SAFETY LOCK AND
LOCK OPENING PROCESS
The present invention relates to a combination security lock intended in particular to equip a door protecting access to a building. More particularly, the invention relates to an access door lock comprising coding means and bolt means translatable over a predetermined reverse stroke after unlocking the coding means in order to open the lock.

In known locks of this type, the coding means are firstly unscrambled to open the lock and must remain unscrambled when the lock is open. The combination selected in the coding means is still displayed on the exterior face of the door after passage of the access by an attendant, closing of the door and, possibly, locking of the lock. The selected combination can thus be read by a malicious person as long as the attendant is inside the building
The invention consists in overcoming the preceding drawback by providing a combination lock in which the coding means must be scrambled to finally open the lock.

 To this end, an access door lock of the type defined in the entry into material is characterized in that it comprises means for stopping the bolt means at an intermediate position of said reverse stroke after unlocking the means of coding, and means for both prohibiting a retraction of the bolt means when the coding means are scrambled and the lock is completely closed, and authorizing a retraction of the end of travel of the bolt means after scrambling of the coding means when the bolt means are substantially at said intermediate position.

Thus substantially at mid-stroke of the bolt means, corresponding to said intermediate position, the coding means must be scrambled in order to be able to complete the reverse stroke of the bolt means and thus open the lock. In the intermediate position, the slight recoil of the bolt means already produced does not allow the opening of the lock, so the button is ensured of compulsory jamming of the coding means before any opening of the lock and penetration of an attendant inside the access, followed by closing the door and locking the lock.

According to the invention, the opening of the lock comprises the following successive steps
a) unscrambling the coding,
b) retraction of the bolt means to said intermediate position,
c) coding interference,
d) retreat at the end of the bolt means,
e) opening the lock.

According to other features of the invention, the lock meets the following security needs
- opening of the lock, and in particular retraction of an intermediate rake between a mechanism with one or more bolts and a coding mechanism with star and ratchet and counter-ratchet play during steps b and d, by means of a safety block with plug-in key from the outside
- preferably interchangeable safety block to meet the desired degree of protection ;;
- translation of the bolts themselves, only after the end of step d corresponding to the end of the retraction of the rake in order to remedy a forcing on the bolts
- quick search of the selected combination, in case of panic or forgetting of the selected combination, from the inside thanks to interior operating buttons to turn the ratchet and counter-ratchet games in the coding means so to visualize a snap of ends of the branches of the star with slots of the counter-ratchets through manholes made in an interior wall of the lock
- control of the safety block from the inside by means of an operating button, which allows rapid opening of the lock, especially when the key is lost
- change of the combination in the coding mechanism only from the inside by means of a second security block with preferably interchangeable key, the change of combination necessarily taking place between steps a and c when the coding is unscrambled and the lock is closed.

Other advantages and characteristics of the invention will appear more clearly on reading the following description of a preferred embodiment according to the invention with reference to the corresponding appended drawings in which
- Fig.1 is a vertical front view of the interior of a combination safety lock and three bolts according to the invention a coding mechanism of the lock being in the unscrambled state;
- Figs.2, 3 and 4 are sectional views taken along lines II-II, III-III and IV-IV of Fig.1 respectively
- Figs. 5 and 6 are front and side views of a lock housing respectively
- Fig.7 is a front view of a plate fixed to the bottom of the housing
- Figs.8 and 9 are front and side views of a bolt drive wheel actuated by a double handle, respectively
- Figs.10, il and 12 are views of ace, side and top of a main bolt tvanslatable horizontally, respectively;
- Figs. 13, 14 and 15 are front, side and top views of one of two secondary bolts translatable vertically opposite, respectively
- Fig3.l69 17 and 18 are front, side and top views of a horizontally translatable rake between the main bolt and a coding mechanism of the lock, respectively; and
- Figs.l9 and 20 are front and top views of a pivoting locking valve on the rake, respectively.

 With reference to FIG. 1, a lock according to the invention comprises a ratchet and counter-ratchet coding mechanism, a bolt opening mechanism and a safety block mechanism cooperating with the two other mechanisms to release the opening mechanism after unscrambling and jamming of the coding mechanism. The three mechanisms are contained in an open parallelepipedal housing 10, forming the palatre of the lock, having a central longitudinal axis XX ′, here horizontal. The case is closed by an interior face of a door leaf P and fixed to the latter by four screws 100. In the following, "interior" and "exterior" are directions respectively oriented inward and the exterior of an access closed by door P, as shown in Figs. 2, 3 and 4.

 Different constituent parts of the three mechanisms are fixed and guided on a plate 11 applied against the bottom of the boot 10 by means of six screws 110 penetrating into threaded bosses on said bottom. Drill hole locations for receiving nipples, crimped abutments, pins, screws or the like relating to fixing and guiding parts in the lock are shown in Figs. 5 and 6 showing the housing 10 and in Fig. 7 showing the plate 11 and will be referenced as the following description proceeds.

 As shown on the right in Fig.l, the coding mechanism comprises a flat combination star 2 having three branches 20riz 202 and 203. The star 2 is rotated clockwise around a horizontal axis of rotation 21 by a wire spring 22. The axis of rotation 21 is fixed perpendicular to the plate 11 and is centered on the axis XX '. The spring 22 has strands subject to two studs 220 and 221 projecting from the outer faces of the star and the plate respectively. Each branch 201, 202, 203 is terminated by a blunt tip 23riz 232, 233 substantially tangential to a circle coaxial with the axis of rotation 21.

 The coding mechanism also includes three sets of ratchet and ratchet 31 32 and 33 having horizontal axes of rotation 301, 302 and 303 angularly distributed around the axis of rotation 21 of the star and arranged between the branches of the 'star. The axes of the ratchets 311, 312 and 313 and of the counter-ratchets 321, 322 and 323 pass through adequate passages and sheaths completely the bottom of the shoemaker 10, the plate 11, a cover plate 12 covering the coding mechanism and fixed by three screws 120 on the plate 11, and the door P, as shown in Fig. 2. Two operating buttons with index mark, such as an interior button 3i2 and an exterior button 3e2 attached to the ends of the axis 3 2 countered in Fig. 2, end each axis of rotation 301 to 303 and are respectively projecting from the inside of the housing 10 and from the outside of the door P. The ratchets 311 to 313 are pinned to the axes 301 to 303 respectively , and therefore integral in rotation with the corresponding operating buttons 9 while the counter-ratchets 321 to 323 can rotate freely around the axes of rotation 301 to 303 respectively. The counter-ratchets 321 to 323 are radially split discs arranged coplanarly with the star 2 between the outer face of the plate il and the ratchets 311 to 313. Each counter-ratchet 321 to 323 is provided with a finger3 called clarinet 331 at 333, sliding in a radial slot of the counter ratchet and pushed towards the periphery of the counter ratchet by a small helical spring (not shown) axial to the slot. The clarinet has a lug abutting in one of the slots made between the teeth of the respective ratchet so that the counter-ratchet and the ratchet are integral in rotation. As shown in Fig. 1, three counting pawls 3419 342 and 343 mesh between the teeth of the ratchets 311, 312 and 313 respectively. Each pawl 341 to 343 is rotating around a horizontal axis of rotation 351 to 353 fixed perpendicular to the plate 11 and returned in the direction contrary to clockwise rotation by a wire spring 361 to 363. Two strands of each spring 361 to 363 are respectively subject to a stud 371 to 373 projecting from the pawl 341 to 343 and to a stud 38 to 383 projecting on deck 11.

 The slots of the three ratchets 311 to 313 receiving the lugs of the three clarinets 331 to 333 determine the combination of numbers allowing the coding mechanism to unlock, the combination being chosen initially by inserting each lug of a clarinet in one of the slots of the associated ratchet brought opposite the associated point 231 to 233 of the star. As long as at least one of the points 231 to 233 of the star is applied against the smooth periphery of the associated counter-ratchet 321 to 323, a pin 24 projecting from the outside face of the branch 20 directed towards the block mechanism is located above the X'X axis, at a distance of 2 to 3mm from it, and the coding mechanism is scrambled. As soon as all the points 231 to 233 of the star are close to the slots of the respective ratchets determining the combination and therefore arrive opposite the respective clarinets 331 to 333 in the counter-ratchets 321 to 323, the star 3 rotates clockwise under the action of the spring 22. The points 231 to 233 respectively push the clarinets radially towards the axes 301 to 303 and the pin 24 crosses the axis X'X and is held in abutment at this position, as will be seen below. At this stage, the points of the star 2 still hold the lugs of the clarinets in the slots of the ratchets determining the combination, and the coding mechanism is unscrambled. The scrambling or unscrambling of the coding mechanism is obtained either by turning the three exterior operation button, such as the 3e2 button, or the three interior operation buttons, such as the 3i2 button.

The coding mechanism is also associated with combination change means in the form of an interchangeable safety block 4 shown in the lower right corner of the
Fig. 1 and in Fig. 2. The safety block 4 is accessible from the inside and crosses horizontally the bottom of the case 10 and the plate 11 and is fixed by a screw 40 and a welded bracket 41 on the plate 11, as shown in Fig.7. The block 4 is conventional and comprises a stator and a rotor rotating by means of a key 42 to be introduced from the inside of the access, as shown in FIG. 2. The rotor of the block 4 is provided with a radial lug 43 which abuts against the underside of a small stud 25 projecting from the outside face of the branch 202 of the star 2, when the key 42 is turned in the opposite direction clockwise inside the access. When the points 231 to 233 are in contact with the clarinets 331 to 333 and therefore the coding mechanism is unscrambled, a slight push of the stud 25 upwards by the lug 43 forces the star 2 to rotate appreciably which releases the clarinet lugs from the slots of the ratchets 311 to 3i3 and thus disengages in rotation the ratchet and counter-ratchet in each set 31 to 33. Ports 261 to 263, forming manholes, holes in the bottom of the case 10 and in the plate allow a new combination to be selected, when the rotation of the key 42 is held in force against the stud 25 by means of the lug 43, The new combination is selected by turning the interior operating knobs urs, such as the button 312, in order to align the lugs of the clarinets with other slots in the ratchets 311 to 313, then releasing the lug 43 of the stud 25 downwards by rotating the key 42 in the opposite direction, which allows the clarinets to go up against the points 231 to 233 of the star.

 With reference to the left-hand part of FIG. 1 and in FIG. 3, the slope opening mechanism comprises a drive wheel 5 rotating in a vertical plane, a main bolt 6p sliding horizontally along the axis X27 D and two secondary bolts 6s and 6i sliding in opposite directions along d 'a vertical axis ZZ'.

The drive wheel 5 has central cylindrical bosses 50 and 51 rotating in coaxial circular holes, Nials made respectively in the plate li and a cover plate 13. your plate 13 covers the opening mechanism in the housing 10 and is fixed to the plate 11 by four screws 130 penetrating into threaded pillars 131 projecting from the plate
As shown in Fig.3 and Figs. 8 and 9, a horizontal operating axis 52 with square section of a double handle 53i-53e through a complementary hole of the wheel 5, central to the bosses 50 and 51 forming hub wheel. The operating axis 52 is centered on the intersection of the axes SXg and YY2. One half of the circular periphery 54 of the wheel 5 is substantially set back a few millimeters from the other half of the periphery of the wheel in order to form two diametrically opposite corners 55, suitable for abutting against a stop 56 projecting from the plate 11. The two corners 55 define the limits of a 180 rotation of the double handle 53i-53e. In the wheel 5 is made a semicircular groove 57 eccentric by half the stroke L of the bolts.

As shown in Figs. 10 to 15, each of the bolts 6p, 6s and 6i has a cylindrical head 60p, 6Os, 60i passing through a side 10p, 10s, 10i of the housing 10 forming a headrest, and a vertical flat tail 61p, 6ifs, 611 The tail 61p of the main bolt 6p has a stud 62p projecting on its internal face and two studs 62s and 621 projecting on its external face. The stud 62p is centered on the axis XX 'between the head 60p and a rectangular light 63p crossed by the boss 51 and is suitable for being guided in the groove 57 of the drive wheel. The pins 62s and 621 are arranged symmetrically with respect to the axis XX ', on either side of the light 63p, and are suitable for being guided in respective rectilinear buttonholes 63s and 631 of the upper 63s and lower 63i bolts. The buttonholes 631 and 63s are symmetrical with respect to the axis XX ', inclined at 450 with respect to this axis and converging towards the head 60p of the main bolt. As shown in
Fig.3, the wheel 5, the tail 61p of the main bolt and the coplanar tails 61s and 611 of the secondary bolts are superposed vertically between the plate 11 and the cover plate 13.

The four pillars 131 projecting from the plate are arranged at the vertices of a rectangle centered on the operating axis 52 and form two-by-two guides for translating the bolts 6p, 6s and 61 along the respective axes XX ' and vv '.

 Referring now to the central part of FIG. 1 and to FIG. 4, the safety block mechanism essentially comprises a member, called rake 7, intermediate between the main bolt 6p and the star 2, a blocking valve. 8 rotatably mounted on the rake, and an interchangeable safety block 9.

As shown particularly in Fige. 16 to 18, the rake 7 is a vertical plate having a thick central part 70, substantially rectangular, a front upper arm 71 and a triangular tail 72. The central part 70 is disposed between a vertical rear edge 64 of the tail 61p of the bolt main 6p and branch 201 of the star extending substantially along the axis
X'X. The upper arm 71 can slide on the plate 11 between the latter and the tail 61s of the upper bolt 6s and against the upper side lOs of the housing 10. The triangular tail 72 has a horizontal side 720 substantially below the axis X 'X. The rake 7 offers three guide grooves 73 parallel to the axis X'X, two made in the arm 71 and one made in the central part 70, receiving horizontal guide pillars 74 projecting from the plate 11. The pillars 74 are surmounted by circlips 75 to apply the arm 71 against the plate 11, and the central part 70 against a flange 740 of the pillar guiding the central part 70.

The collar 740 serves as a spacer between the plate 11 and the central part 70 of the rake, as shown in FIG. 4, in order to create a gap between the plate 11 and the tail 72 of the rake for the passage of the branch 201 of the star 2.

 The blocking valve 8 is shown in detail in Figs. 19 and 20 and is in the form of an elongated piece with a longitudinal section in L. A thin front end of the valve 8 is mounted for rotation about a fixed axis 80 on a recess 701 of the central part 70 of the rake, above the axis 1 (410. A lower edge 81 of the valve is applied against a shoulder 702 of the recess 701 by a strand of a wire spring 82 fixed by screw 83 on the recess 701. A bevelled rear rear end 84 of the valve 8 overhangs the horizontal edge 720 of the tail 72 of the rake, passes over the end of the external face of the branch 201 of the star 2 and in front pawn 24.

 Safety block 9 is located under the central part 70 of the spleens. I1 is similar to safety block 4s except that it crosses horizontally right through the bolt holder 10, the plate 11 and the door P in order to be actuated by a key 90 from the outside and by a button maneuver 91 from the inside. Thus the safety block 9 is fixed by a screw 92 and a bracket 93 on the plate 11, as shown in detail in FIG. 7, and comprises a rotor provided with a radial lug 94. The lug 94 cooperates with two adjacent notches 703 and 704 having Zongeurs equal to L1, formed in a lower horizontal edge of the central part 70 of the rake 7. The overall length of the notches 703 and 704 is at least equal to the length L of the recoil stroke bolts 6p, 6s and 61 so that the rake 7 is translated backwards, towards the star 2, after two turns of the key 90 or of the button 91 and thus allow a sufficient stroke of the bolt 6p during the door opening.

 The operation of the lock is as follows.

 It is assumed that door P closes the access and that the lock is locked. In this case, the combination in the coding mechanism is scrambled and at least one of the points 231 to 233 of star 2 is applied against the smooth periphery of the corresponding counter-ratchet 321 to 323. The pin 24 on the branch 201 is in the high position and is located just in front of the rear tapered end 84 of the locking valve 8 which prevents any recoil of the rake 7. The central part 70 of the rake 7 is applied against the rear edge 64 of the main bolt 6p which prevents any retraction of the bolt 6p by rotation of the external handle 53e. In addition, although the locking of the bolt 6p between the headrest 10p and the rake 7 ensures a locking of the secondary bolts 60s and 601 thanks to the connecting studs 62s and 621 abutting ends close to the buttonholes 63s and 631, a rectangular abutment block 710 (FIGS. 17 and 18) projecting from the outside face of the arm 71 of the rake and located under the tail 61s of the upper bolt 6s, as shown in FIG. 3, prevents any recoil down the head 60s of the upper bolt. According to another variant, a break-in at the level of the head 611 of the lower bolt 61 can be prevented by means of a second arm of the rake, similar to the arm 71, provided with a stop block similar to the block 710. Furthermore, the notch 703 has a rear end substantially aligned with the vertical axis of the safety block 9.

 To proceed with opening the door, five successive steps a, b, c, d and e are carried out.

 a) Depending on the selected combination, the three external operating buttons, such as the button 3e2, are rotated in order to align the tips 261 to 263 of the star respectively with the respective clarinets 331 to 333; under the action of spring 22, the star 2 rotates clockwise in the plane of Fig.l, until the pin 24 strikes the rear end of the horizontal edge 720 of the tail 72 of rake 7, as shown in FIG. 1. At this stage, the pin 24 is released from the end 82 of the blocking valve. However, a forced rotation of the handle 53e is only likely to cause an insufficient translation of the bolt 6p and therefore of the rake 7 since the pin 24 is only separated by a distance L1 from a projection forming a stop 721 on the edge 720, said distance L1 being substantially less than half the stroke of the bolts; in addition, this forced rotation is hampered by the block 710 under the head of the bolt 60s.

 b) A first turn of the key 90 in the safety block 9 allows the lug 94 to move the rake 7 back along the length L1, equal to the length of the first notch 703. In this case 3 the projection 721 abuts against the pin 24 of the star, and the tapered end 84 of the valve 8 passes over the pin 24. The rake 7 is thus blocked substantially halfway back. A rotation of the outer handle 53e does not centralize the translation of the bolts as in step a, since the block 710 is still located partly under the head 60s of the upper bolt 6s.

 c) your selected combination is again scrambled by any rotation of at least one of the operating buttons, such as the button 3e2. the star 2 turns counter-clockwise following the return of the points 231 to 233 on the peripheries of the counter-ratchets 321 to 323, which returns the pin 24 to the high position, as at the beginning of the step a, and simultaneously, goes up the tapered end 84 of the valve 8 which is applied against the pin 8 thanks to the elastic return towards the bottom of the spring 82. In the high position, the pin 24 is separated from the horizontal edge 720 of the tail of the rake from a distance appreciably greater than the height of the stop 721 in order to allow a retraction of the end of travel of the rake to the next step d.

 It should be noted that if the scrambling of the coding mechanism is not carried out before an attempt at a second turn of the key described in the next step d, the pin 24 remains in horizontal alignment with the stop 721 and prevents any recoil of the rake and all unlocking of the lock.

 d) A second turn of the key 90 in the safety block 9 causes a retraction of the end of stroke of the rake 7 over a length L2 equal to the length of a notch 703, 704 increased by the thickness of the separation between the notches 703 and 704, thanks to the push of the lug 94 against the rear end of the notch 704. After the second turn of the key, the front end of the notch 704 is aligned with the vertical axis of the block security 9.

 When the rake retreats over the length L2, the stop 721 passes under the pin 24, the length of the tail 72 of the rake being at least as great as L1 + L2. At the end of the recoil stroke L1 + L2 of the rake, the rear edge 64 of the main bolt 6p is separated from the front edge of the central part 70 of the rake by the distance t1 + t2 which is at least as great as the run L bolts. Simultaneously, the block 710 of the arm 71 of the rake is completely free from the vertical extension of the head 60s of the upper bolt 6s. At the end of the rake recoil stroke, the block 710 is located below and to the right of the head 60s, which authorizes a retraction of the bolts at the next step e.

 e) A half-turn rotation of the handle 53e and therefore of the wheel 5 in the clockwise direction of rotation causes the stud 62 to slide along the axis XX 'in the eccentric groove 57 until the pin 62 abuts against the blind end of the groove 57 which is then to the left of the operating axis 52, and horizontal sliding of the pins 62s and 621 of the bolt 6p in the buttonholes 63s and 631 ce which brings the bolts 6s and 6i vertically towards the operating axis 52. In this case, the bolts 6p, 6s and 6i have moved back by a length L and the heads 60p, 60s and 601 are completely released from corresponding strikes (not shown) of the lock and completely contained in the case 10. The door P is then open.

 Then, the door P can be closed from the inside by turning the interior handle 531 by half a turn to advance the bolt heads 60p, 60s and 601 in the corresponding strikes.

However, this closing from the inside can be obtained directly and without a key by two turns of the operating button 91 which closes the door and locks the lock in a single operation and prevents any opening from the outside, except to proceed exactly according to successive steps a to e. Indeed, following the two turns of the button 91, the rake 7 and the bolt 6p are moved forward over respective distances L1 + L2 and L by means of the pushes of the lug 94 against the front ends of the notches 704 and 703. The stop 721 of the tail of the rake passes under the pin 24 to reach the front position shown in Fig.l. Simultaneously, the tapered end 84 of the blocking valve 8 slides on the pin 24 in the high position and falls back in front of the pin 24, against the shoulder 702 under the action of the spring 82.

The tapered end 84 is then in front of the pin 24 which prevents any retraction of the rake 7 and the bolts and therefore locks the lock.

Of course, closing the outside by two turns of the key 90 in a direction of rotation opposite to that of steps b and d locks a lock of the lock.

Still inside the access, a reopening of the door
P especially in case of panic can be obtained easily and quickly without a key and even in ignorance of the selected combination. Indeed, steps a to e are carried out again from the inside. In the step at the combination can be easily found by searching through the three interior manholes 261 to 263 for the alignment of the points 231 to 233 respectively with the clarinets of the counter-ratchets 321 to 323 by means of rotations of the interior operating buttons of the coding mechanism, such as button 312 (Fig. 2). In step b, the button 91 (Fig. 4) instead of the key 90 is turned one turn. In step c, at least one of the three interior operating buttons, such as the button 3i2 (Fig. 2), instead of the external operating buttons, are turned to scramble the combination. In step d, the button 91 instead of the key 90 is turned a second turn.

Then in step e, the interior handle 53i (Fig.3) instead of the exterior handle 53e is turned a half turn.

 Furthermore, it will be noted that the change of combination by means of the safety block 4 can only be carried out from the inside of the access and only between steps a and c, when the pin 24 is in the low position, against the horizontal edge 720 of the tail of the rake, and therefore when the lock is closed.

 Other embodiments belonging to the subject of this patent application can be deduced by a person skilled in the art from the preferred embodiment described above. In particular, the arrangement of the tail 72 of the rake 7, of the pin 24 and of the pivoting valve 8 can be adapted in a lock not comprising a rake, the rake 7 and the main bolt 6p being assembled in a single piece; in this case, the safety block is removed and the opening is controlled by the handle 53e or 531, or else the drive wheel 5 is removed and the opening is controlled directly by the key 90 or the operating button 91 , so that the opening steps d and i are concomitant.

Claims (21)

 1 - Access door lock comprising coding means (2,3) and bolt means (6,7) translatable over a predetermined reverse stroke (L1 + L2) after unlocking the coding means with a view to open the lock, characterized in that it comprises means (72) for stopping the bolt means (6S7) at an intermediate position (L1) of said reversing stroke (L1 + L2) after unlocking the coding means, and means (8) to both prohibit a retraction of the bolt means (6,7) when the coding means (2,3) are scrambled and the lock is completely closed, and authorize a retraction of the end of travel (L2) of the bolt means (6,7) after scrambling the coding means (2,3) when the bolt means are substantially in said intermediate position.  2 - Lock according to claim 1, characterized in that the coding means (2,3) comprise a pin (24) which is in a first position (high) when the coding means are scrambled and which is at a second position (low) when the coding means are unscrambled, the pin (24) being successively in the first position for locking in translation the bolt means (6,7), in the second position for stopping the bolt means (6, 7) at said intermediate position, and at the first position for authorizing said retraction of the end of travel of the bolt means (6,7).  3 - Lock according to claim 2, characterized in that the coding means (2,3) are of the rotating star type (2) having branches (201n202,203) cooperating with ratchet games and against ratchet (31932 '33) and in that said pin (24) is integral with one (201) of said branches.  4 - Lock according to claim 3, characterized in that each set of ratchet and ratchet (31 to 33) is capable of turning by means of an operating button (3e) outside the access and d 'an operating button (3i) inside the access.  5 - Lock according to claim 3 or 4, characterized in that it offers on the inside of the access, manholes (261 to 263) respectively opposite the ends (231 to 233) of the branches (201 to 203 ) of the star (2) cooperating with slots of the counter-ratchets (321 to 323).  6 - Lock according to any one of claims 2 to 5, characterized in that the means for stopping (72) consist of a song (720) secured to the bolt means (6,7) and parallel to the direction translation (XX ') of the bolt means, said edge (720) having a first end against which said pin (24) abuts in the second position (low), and a second end forming a projecting stop (721) for abutting the pin (24) when the bolt means reach said intermediate position.  7 - Lock according to any one of claims 2 to 6, characterized in that the means for prohibiting and authorizing comprise an element (8) pivotable on the bolt means (6,7) and returned by spring (82) to a stable position at which the pivotable element abuts against the pin (24) at said first position in the direction of translation (XX ') of the bolt means (6,7) when the coding means (2,3) are scrambled and the lock is completely closed, said pin (24) being released from said pivotable element (8) after the pin has passed from said first position (high) to said second position (low) and when the bolt means (6,7 ) are translated to said intermediate position, and said pin (24) pivoting the pivotable element (8) against the action of the spring (82) when the pin (24) moves from said second position to said first position and the bolt means (6,7) are at said intermediate position.  8 - Lock according to any one of claims 1 to 7, characterized in that it comprises a safety block (9), preferably interchangeable, provided with a lug rotor (94) cooperating successively with two notches ( 703,704) of the bolt means (6,7) aligned in the direction of translation (XX ') of the bolt means, a first turn of the rotor after unlocking the coding means (2,3) causing the bolt means to move back towards said intermediate position (L1), and a second revolution of the rotor after scrambling the coding means (2,3) causing the end of stroke retreat of the bolt means.  9 - Lock according to claim 8, characterized in that the safety block (9) can be actuated from the outside of the access by a key (90) and from the inside of the access by an operating button (91).  10 - Lock according to any one of claims 1 to 9, characterized in that the bolt means (6,7) comprise a main bolt (6p) and a rake (7) translatable independently in the same direction, said rake (7) supporting said means for stopping (7) and said means for prohibiting and authorizing (8).  11 - Lock according to claim 9, wherein the bolt means comprise at least one secondary bolt (6s) translatable by the main bolt (6p) perpendicular to the direction of translation (XX ') of the main bolt, characterized in that the rake (7) comprises a stop (710) blocking the translation of the secondary bolt (6s) as long as the rake has not reached the end of the reversing stroke (L1 + L2).  12 - Lock according to claim 8 or 9 and to claim 10 or 11, characterized in that said notches (703,704) are formed in the rake (7) so that the two turns of the rotor of the safety block (9) cause complete retraction of the rake only.  13 - Lock according to any one of claims 1 to 12, characterized in that it comprises means (4) for changing the coding in the coding means (2,3), preferably from the inside of access.  14 - Lock according to claims 3 and 12, characterized in that the means for changing comprise a safety block (4), preferably interchangeable, provided with a lug rotor (43) cooperating with a stud (25) on the '' (202) of the branches of the star (2) to force the star to rotate when the coding means (2,3) are unscrewed in order to disengage in rotation the ratchet (311 to 313) and the counter-ratchet (321 to 323) in each game (31 to 33).  15 - Method for opening the lock according to any one of claims 1 to 14, characterized in that it comprises the following successive steps  a) unscrambling the coding,  b) retraction of the bolt means to said intermediate position,  c) coding interference,  d) retreat at the end of the bolt means,  e) opening the lock.  16 - Method according to claim 15, characterized in that steps b and d are each carried out by a turn of a key (90) or an operating button (91) of a safety block (9) .  17 - A method according to claim 15 or 16, characterized in that step e is performed by rotation of an outer handle (53e) or inner (531).  18 - Method according to claim 1, characterized in that steps b and d are performed by rotation of an outer handle (53e) or inner (531).  19 - Process according to claim 16 or 18, characterized in that steps d and e are concomitant.  20 - Method according to any one of claims 15 to 19, characterized in that the step operated from the inside of the access consists in viewing through manholes (261 to 263) of the lock and in searching by rotation of internal operating knobs (31) of ratchet and counter-ratchet games (31 to 33) in the coding means (2,3), the snap-fastening of ends (23 to 233) of branches (201 to 203) of a rotating star (2) included in the coding means with slots of the counter-ratchets (321 to 323), respectively.  21 - Method according to any one of claims 15 to 20, characterized in that it comprises between steps a and c, a code change in the coding means (2,3), preferably operated from inside the access.