This refers to the present invention of a lock which does not need a key but has a secret system of mechanic simplici ty.

The lock of the invention in question has in its versa¬ tility application in many fields-doors of residencies, safes , vaults or indeed any equipment which demands the protection equivalent to a bank safe. -Che locks are widely available on the market and normally consist of cylinders with groups of secret codes. They have the possibility of being able to give alse indications of coincidences of combinations which only make it more difficult for some time for strangers to try to violate them, The usual way for the above-mentioned locks to increase security is by presenting the manipulation buttons of the secret codes of its marked limbs which by simply permitting a greater number of positions increases the number of possible combinations. The invention in question shows that it can overcome the security problems because it has a system which impedes any attempt to feel or listen and determine the position of the passage of the pins even with the help of sophisticated instru¬ ments. ϊhe objective of this invention is to avoid that the secret of the lock be determined in the usual wat by "experts" when breaking into safes.

This objective is realised by the lack of any noise which could in any way indicate the position of the cylinder's holes through which the pins should pass to liberate the bar.

The anticipated rebound of the cylinder occurs s multaneous y with the pin orcing it to slide and produce a uni orm noise resulting from the passage of the pin and the rebound of the cylinder, In order for the pin to penetrate the hole predestined by the lock's secret it is necessary for the cylinder to be pulled or pushed from its pre-established position in which only in that position it is possible to turn the cylinder. When the cylinder is pulled or pushed to the position in which the hole can coincide with the pin, the expected grooves in the body of the cylinder slot into place fixedly with a plate possessing a number of teeth equal to the number of grooves on the cylinder and which is solidly attached to one of the walls of the lock's encasement (front or back). Once the cylinder is pulled or pushed from its position of free rotation and linked in the serrated hole, the cylinder will no longer rotate. As the cylinder will no longer turn when it is the position which al¬ lows the penetration of the pin into the hole, it is impossible to determine the position of the said hole by the noise emitted by its passage in contact with the pin.

The maximum security of the secret of this lock lies in the fact that the cylinder is only free to rotate when it finds itself in the position in which the pin slides into the rebound and as this is totally smooth it is impossible to determine the secret of the lock by the rotation of the cylin¬ der.

Figure I is a view of the perspective of the lock in question in its locked position.

Figure 2 is a view of the perspective of the lock in its unlocked position, showing the pins inside the holes in the cylinders.

lock in the same position as Figure I.

Figure 4 is a view of the side of the lock's interior.

Figure 5 is an enlarged view of the linking mechanism ^" of the cylinders.

Figure 6 is an enlarged view of the grooved cylinder clearly showing the rebound.

Figure 7 is a view of the external part of the lock.

Figure 8 is an enlarged view of the lock's bar clearly showing the rebound's link.

In more detail the lock is composed of three cylinders 2 joined to its axes 3 by nuts 4. The principal characteristics of the cylinders are the rebounds 5 which divide the surface into two equal parts, 6 & 7 both grooved, and the lacerated holes 8 which penetrate both parts right- through to the surface of the axis 3-

The technical design of the rebound as previously mentioned is to stop the determination of the localisation of the hole. The technical design of the grooves is to fix the cylinder to the plates of the link 9 Fig. 5.

External rebound of the cylinder 2 grooves and hole of the passage of the pin which orm a collection of technical characteristics non-existent in equipment intended or the same purpose on the market.

The principal aim of the characteristics described above is to make the secret of the system invented inviolable.

The bar 10, fig. 8, also constitutes an innovatory characteristic as a result of the rebound II which is part of its structure and possesses the specific possibility to serve as a brake for the bar referred to. *

RE

e , . specific purposes which we will proceed to mention.

A) It serves as a base for the pins, 13, 1 , 15-

B) It stops the course of the bar 10 ^~ bj holding the rebound II of the same through its. own rebound.

C) As a result of its design its own weight makes the. pins descend by gravity which liberate the cylinders and make the whole system open.

The eccentric 17, fig. 2, acts as a lever raising the base when the right holes in the cylinders find themselves coincidental with the pins, thus allowing the consequent liber¬ ation of the brake which can then be moved and the entrance opened.

The plates of the link 9, with serrated holes 21, fig. 5 _. fills the purpose of fixing the cylinder thus prohibiting any tactile or auditory attempt to determine the position of the hole or the passage of the pin.

The use of the rebound in the cylinders and the plates of the link represent in the system's function of this invention the completion of a mechanical conception unknown in industrial terms and which will not necessitate elevated production costs but comprise maximum security, technical innovation and reduced costs.

Function of the lock. The action of unlocking the lock which in practice is equivalent to opening the door, requires that the three cylin¬ ders 2 are in a position whereby the serrated holes 8 in them are aligned vertically with the pins. For this to occur it is necessary to know beforehand the numbers which correspond to this position. These numbers are engraved into the metal which the external controls are made of and which are linked

con . centres of the three cylinders.

The alignment of the cylinders holes with the pins fixed to the base 12 permits that this, on being lifted by means of rotation or turning by 180° from the eccentric 17. liberates the rebound II from the brake 10 allowing its action or movement by means of rotating its external controls or by displacing its internal arm.

When the lock is locked the cylinders will position themselves with the respective rebounds in the same vertical line as the pins. This will signify that they,even when forced upwards, by means of the action of the base through the ec¬ centric, will meet smooth surfaces which in no way will indicate the position of the holes. It is evident that in these positions the cylinders and their respective axes will girate freely and this being the case the act of putting together the combination- which is placing the holes in the same alignment as the pins- will not signify that the afore-mentioned holes are situated laterally in relation to the rebound. At the moment when the cylinders are activated either orwards or backwards by means of pushing or pulling the axes or controls on the outside of the lock or externally or in¬ ternally from the door the same will be fixed and the plates of the link will lose their ability to girate freely. In the case o£ this fixation it will happen that the lock continues to be barred, without the holes in the cylinders being in the same alignment as the pins, in other words the door will not be able to be opened. In the case of the holes being aligned with the pins the base will be able to be activated by way of turning the eccentric, resulting in the liberation of the bar's rebound which will permit this to be released, thus opening the door."

linking mechanism signifies the total impossibility of tactile or auditory attempts which would permit the determination of the position of the holes, making it impossible-to know the corresponding numerical combinations.

The technical details of the rebound and the plates of the link consist of two modest mechanical contributions to the technology of any secret safe or lock system and also security equipment controlled b numerical combinations or series. Another integral part of the lock is the encasement 19 and the back sheet which is mounted by way of screws.