"DOUBLE MAP SAFETYLOCK FOR DOORS AND GATES"

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Field of the Invention This invention basically concerns the sector of locks for doors and gates and refers, in particular, to a double map lock that also has a false or worksite key. State of Technology

The type of map locks considered here are already known; they have a lock bolt inside a rigid box housing associated to a pack of stop plates, called gorges, and a spring-latch with a key used to move them from a forward closed position to a retracted open position.

The mechanism that opens and closes these locks is the pack of gorges of which there can be six, featuring differentiated passage notches which, when aligned, create the profile of the operating key, called bitting.

The keys used with this type of lock are called map keys when the key has a single bit, and double map keys when they have two.

When a key with a suitable bit profile is turned inside the lock the gorges are aligned, centring the notches to let the stop pin pass, called Mentonnet, one with the bolt.

Normally, the functions of a lock operated by a double map key are:

- operating the four turn lock bolt where the key has to be turned 180° for each turn,

- opening the spring-latch, turning approximately another 90° in the lock bolt opening sense. In this type of lock each gorge has five notches for the four turns plus operation of the spring-latch. The key has two different bitting maps, each with six incisions, one for each of the six gorges.

In double map keys, the maps are repeated on the key, turned 180° on the horizontal plane with respect to the key's centre because the gorges are arranged asymmetrically inside the lock. Then there is a central area which is not bitted, used for the lock bolt.

The key can be inserted or removed every two turns, on both sides of the lock, turning it 180° on the horizontal plane. The key's asymmetrical cross- section prevents it from being inserted incorrectly. However, despite the increasing level of security of such systems, if this lock is installed on doors or gates of buildings under construction, it might be necessary to give a key to the worksite personnel to allow their access.

In such an event though, there is a risk of key duplication, rendering vain all efforts made to prevent fraudulent opening of the lock. For greater ease of mind, the end user often prefers to modify or change the lock installed previously, during work on the site, at additional expense.

To prevent this, we can have what are called temporary or worksite keys that are different from the main keys that the end user will have, the so-called "master" keys. Likewise, traditional double map locks, besides the "master"

keys that can turn the whole lock, can be fitted with false keys, also known as "worksite keys", that can only turn the lock partially.

However, traditional false keys maintain their function for the entire life of the lock, and there can be two different types: ' - "deadlock" false or worksite key that only opens the spring-latch;

- the "two turn" false or worksite key that opens the first and second turns of the spring-latch.

But even this has a drawback: none of the false keys can be disabled meaning they can be used again or even duplicated to open the lock if the latter has not been closed with all the locks by the master key.

Taking this into consideration, locks with double maps have even been proposed with a temporary device comprising a pack of gorges that can only be turned with the worksite key and later substituted with a definitive nucleus of gorges when it is no longer necessary to leave worksite keys with others. But once the lock or device with the pack of gorges has been changed, the worksite key can no longer be used, should the necessity arise, without intervening on the door. Purpose and Summary of the Invention

The purpose of this invention is to overcome this drawback with a double map lock that can be operated by a temporary false key or worksite key but which also includes a device that can automatically disable such a temporary or worksite key the instant the master key closes the lock completely for the first time and which can, if needed, be reactivated as many times as wanted simply by using another resetting key, without intervening on the door.

This purpose is achieved in agreement with the invention by means of a double map safety lock conforming to the following process claim 1 , and incorporating therein a system activated for using the false or worksite keys that can be deactivated with the master key in order to disable their use; if and when the need arises it can be reactivated and the false/worksite key used - which could be for maintenance work or to allow entrance to others for a certain period of time. A Brief Description of the Drawings

The invention will be illustrated in detail following the description that refers to the enclosed drawings - which are approximate but not limiting - where:

Fig. 1 shows a stop plate or gorge in one of its configurations;

Fig. 2 shows a master key with its map;

Fig. 3 shows an exploded view of some of the lock components according to the invention;

Fig. 4 shows a rebitting lever that cannot be reactivated once it has been deactivated;

Fig. 5 shows a rebitting lever that can be reactivated even if it had been deactivated; Fig. 6 shows an inside view of the lock being used with a false key, with the rebitting lever that can be reactivated and the lock bolt retracted in the opening position;

Fig. 7 shows a similar inside view of the lock but with the lock bolt progressed three turns using a master key with the rebitting lever deactivated;

Fig. 8 shows a deadlock false key;

Fig. 9 shows a two turn false key;

Fig. 9a shows the gorge that stops the lock bolt at the second turn;

Fig. 10 shows a resetting key;

Fig. 11 shows the inside view of the lock in the rebitting lever reset condition, so the false keys can be used again;

Fig. 12 shows the inside view of a lock with a rebitting lever that cannot be reactivated once it has been deactivated. Detailed Description of the Invention

These drawings show a lock that can be operated by at least two keys; a main or master 100 key and at least one false key or worksite key type 101 or of another type 101a, with a different bitting.

The lock consists of a rigid box housing 11 with cover 11' in which a lock bolt 12 and spring-latch 13 are inserted, associated kinematically. The lock bolt 12 has a supporting plate 14 over which a pack of gorges 15 is placed, moved and guided in the usual way, each one with a notched window 16, defining the passage notches 17. The bitting of the keys operating the lock corresponds to the layout of the gorge notches, creating a passageway for the stop pin 18, called Mentonnet, fixed to the lock bolt 12 plate 14 and which allows the lock bolt to move only in the conditions defined by the bitting of the map key associated to the lock.

As happens with the usual technique, in a four turn lock and as shown in Fig. 1 , each gorge has five notches which are divided into X notches to operate

the second and fourth turn of the lock bolt and spring-latch, and into notches Y to operate the first and third turn of the lock bolt.

The master key 100 has two different bitting maps, one corresponding to the "X" notches and one to the "Y" notches, with six incisions each, one for each gorge, giving a total of 12 incisions, named with letters from "A" to "L" as shown in Fig. 2 and where each incision can have six different bitting radius values.

In this way, thanks to the gorges 15 and stop pin 18 interacting with them, the lock bolt 12 can be moved with all the keys provided between an opening position, where it is retracted into the rigid box housing, and a closing position, at least partial, where it juts from said housing to fit into the corresponding slot in the fixed part of a closing system, door or gate.

When the key is disengaged the gorges 15 notches are normally misaligned and stop pin 18 engages with the gorge notches, blocking the gorges and preventing the lock bolt from moving.

When a key is inserted and turned in the lock, each one of its bits engages with the corresponding gorge and, if the key has the right profiles, each gorge is moved until it is aligned, creating a passage way to let the stop pin, one with the lock bolt, slide along.

In the example given, the keys associated to the lock include, besides the main key 100, called master, at least one temporary key, called a false or worksite key, the latter, deadlock type 101 with a false map for the "Y" notches, or with two turns 101a, differs from the master key in the incisions corresponding to at least one gorge.

The lock according to the invention also includes, in association to gorges 15, a rebitting lever 20 that does not interfere with lock bolt 12 movements. The rebitting lever 20 interacts with one of the gorges, here also referred to as the stop plate 15'.

The rebitting lever 20 rotates on a fulcrum pin 21 that fixes the lever to an additional supporting plate 22 fixed to the rigid housing 11. Said supporting plate 22 has a slot 23 that is at the same level as the stop pin 18, Mentonnet, which also passes through it. Starting from the relative oscillation pin 21 , the rebitting lever 20 has a vertical arm 24 that extends along the side of the corresponding stop plate 15' facing the end of lock bolt 12, and a horizontal arm 25 that extends above the upper edge of the same gorge 15'.

The bitting of all the notches on stop plate 15' is identical.

The vertical arm 24 of said lever 20 has a hook 26 that engages with the lower horizontal edge of stop plate 15' to lock it in a neutral position, where it finds itself elevated with the relative window permanently at the level of the stop pin 18, consequently the window notches do not interfere with this stop pin nor with any bitting of the false keys that can operate the lock -Figs. 6, 7-.

On the other hand, the horizontal arm 25 of the rebitting lever 20 finishes with a side pin 27 - Figs. 4, 5 - that is inserted and slides along cammed slot 28 created in the lock bolt's 12 plate 14 -Fig. 6-, shaped so as to rotate and keep the lever disengaged from the corresponding stop plate 15' until it is level with the other gorges, from the third closing turn. Basically, the rebitting lever 20 oscillates between an active position - Fig. 6 - where it hooks and blocks the corresponding stop plate 15' in said neutral position, and an inactive

position - Fig. 7 - corresponding to the third turn, where it finds itself in the position to disengage said stop plate 15'.

The cammed slot 28 in the lock bolt plate has a section 28' of its length, corresponding to the first two turns of the lock bolt, dimensioned so as not to interfere with the side pin 27 of the rebitting lever 20 when this lever is in the active position of blocking the corresponding stop plate 15', while the profile of the remaining section 28" of said slot, corresponding to the third and fourth turn, is such that it causes the rebitting lever 20 to rotate towards its inactive position, releasing the stop plate.

The horizontal arm 25 of the rebitting lever 20 may also be equipped with a resetting overhang 29 - Fig. 5 — above the upper part of the stop plate 15', which, where contemplated, resets the position of said stop blocked by the hook 26 of the vertical arm 24 of lever 20 when it had previously been deactivated.

Note also that the vertical arm 24 of the rebitting lever 20 may also be equipped with a stop mechanism 30, like as a ball with spring or pin with spring, with the purpose of alternately engaging one or the other of the two notches 31 , 32 in the cover 11 ' of the rigid box housing 11 so as to positively stop said lever both in the active and inactive positions.

In the lock described above, the presence of the rebitting lever 20 does not prevent normal use of the relative master key 100, to completely close the lock bolt with all its turns, and then to open both the bolt and spring-latch.

In comparison to similar traditional locks, the double map lock in this invention equipped with rebitting lever 20, does offer some additional functions.

It can be fitted with a false or worksite key, type 101 or 101°, temporary, disabled and resettable according to the user's needs with no intervention required to the door using only the master and resetting keys.

A false key or worksite key 101 can be the deadlock type - Fig. 8 - with false bitting of the Y notches and bitting of the X notches identical to those of the master key 100, except for the incisions A corresponding to the gorges 15'. When the rebitting lever 20 is in the active blocking position of the corresponding stop plate 15', said key 101 allows the spring-latch to be opened only if the lock is open and remains enabled only until the third turn is engaged with the master key 100, which disables it automatically, rendering it for ever unusable because the incisions A do not match the bitting of the corresponding gorge 15'.

A false or worksite key 101a can also be the 2-turn type -Fig. 9 - with the third and fourth turns blocked achieved by having the same conditions as a traditional two-turn worksite key where some incisions, such as E-H in Fig. 9, differ, corresponding to the gorge 15" — Fig. 9a - while lacking some notches to operate the spring-latch and the first and second turn. In this case, when the rebitting lever 20 is in the active blocking position of the corresponding stop plate 15', false key 101a allows operation of the spring-latch and first and second turns and it too remains enabled only until the third turn is engaged with the master key 100, which automatically disables it, rendering it unusable.

In both conditions in fact, when the third turn is engaged with the master key 100, the side pin 27 of the rebitting lever is engaged by the profile of the second section 28" of the cammed slot 28 of the lock bolt plate 12 which

causes the lever to oscillate towards its inactive position of releasing the stop plate 15'; this position is maintained by the spring stop mechanism 30.

When it has no resetting notch - Fig. 12 - the rebitting lever 20, after it has moved into the inactive position, stays there all the time, held by the stop mechanism 30, and there is no possibility of it being reactivated, so the false keys remain disabled and the lock can only be operated by the master key 100.

When, however, the rebitting lever 20 is equipped with a resetting overhang 29, when it is deactivated by the master key 100 it need only be temporary, in the sense that said rebitting lever, after being moved into the inactive position, can be reactivated again so that false keys 101, 101a can be used again, wherever requested and without intervening on the door and where operations are only possible with the lock open or closed up to the second turn using a resetting key 102 - Fig.10 - that is inserted in the lock, turned one complete turn, in either direction indifferently, and then taken out. The resetting key is so configured that it does not interact with plate 14 of lock bolt 12 and as it rotates it lifts at least the stop plate 15' such that, meeting with the resetting overhang 29 of the rebitting lever - Fig. 11- it forces the latter to oscillate towards the active position to engage and block said stop plate 15' in the neutral position again which allows the false keys to be used.