EP3848913A2

EP3848913A2 - Security system for locks

Info

Publication number: EP3848913A2
Application number: EP20383112.8A
Authority: EP
Inventors: Santiago Niembro Zarraga
Original assignee: Individual
Current assignee: Individual
Priority date: 2019-12-17
Filing date: 2020-12-17
Publication date: 2021-07-14
Also published as: ES1244979Y; ES1244979U; EP3848913A3

Abstract

It allows providing additional protection based on the incorporation of alarm means to alert both visually and acoustically about the attempted manipulation and / or forced opening of the lock, the security system being applied in locks that comprise a box (1), a latch mechanism (2) and a cylinder (3) that has a key mechanism to operate the latch mechanism (2), wherein said security system comprises: a fixed plate (10), a movable plate (20) supported on the fixed plate (10), fixing means (30) of the fixed plate (10) on the lock, moving means (40) of the movable plate (20), means of retention (50) of the movable plate (20), and alarm means (60) configured to emit an acoustic signal in the event of attempted tampering or forced opening of the lock.

Description

OBJECT OF THE INVENTION

The present invention belongs to the field of locks, and more specifically to security mechanisms to prevent unauthorized opening of locks.
The main object of the present invention is a security system for locks that provides additional protection based on the incorporation of alarm means to alert both visually and acoustically about the attempted tampering and/or forced opening of the lock. For use in locks that have already been assembled, actively protecting them in the event of an intentional breakage of the lock cylinder.

BACKGROUND OF THE INVENTION

At present, many variants of locks are known, based on sophisticated key mechanisms, and whose main objective is to avoid forced opening by third parties and/or improper manipulations thereof, without the corresponding use of the key.
More particularly, in the field of security against theft, the locks incorporated in the enclosures play a fundamental role in preventing their unauthorized opening.
Generally, the key mechanisms with which the locks are operated are based on the incorporation of an independent cylinder, installed in the locks through a predefined hole for mounting said cylinder. In this sense, a very widespread common technique to manipulate and fraudulently access the closures consists of forcing the removal of the cylinder by simply pulling or pushing from the outside, so that, once the cylinder is removed, it is possible to easily act on the lock mechanism without the need to use a key, all through the cylinder's own mounting hole.
In the state of the art, the patent application with publication number ES2367736A1 , corresponding to the same holder as the present invention, is known. Said document describes an anti-theft post-break protection system for locks, and more specifically a protection of the access hole to the lock, the hole left by the cylinder after its removal. Thus, said protection is carried out by moving a mobile plate that covers the access hole to the interior of the lock, as represented in figure 1.
However, said current protection system is capable of being improved since it works in collaboration with a locking element movable under the action of a traction spring housed inside the lock box. This solution has the great drawback that it can only be installed in those locks provided with said space for the locking element, not being applicable in the rest of locks without a technical operation on them, which entails costs for the user.
Another problem in current security systems for locks is that they can be manipulated and/or forced by third parties without any type of deterrent, alert or alarm signal, be it acoustic or visual.

DESCRIPTION OF THE INVENTION

By means of the present invention the aforementioned drawbacks are solved by providing a security system for locks that allows maximum protection, incorporating alarm means, to alert both visually and acoustically about the attempted manipulation and/or forced opening of the lock, being applied to both new locks and locks already mounted, actively protecting them in the event of intentional breakage of the lock cylinder. It should be noted that for the execution of this invention the main focus has been placed on key aspects for a security system such as: reliability, functionality, operational flexibility and low consumption.
Furthermore, by means of the security system described herein, the locks do not require additional construction requirements, that is, they do not need to be structurally modified by a professional technician, as it has been occurring so far.
The security system for locks described herein is applicable to locks that comprise a box, a latch mechanism housed inside the box, and a cylinder that passes through the box and which has a key mechanism to actuate the latch mechanism.
More particularly, the security system of the invention comprises: a fixed plate; a movable plate supported on the fixed plate; means for fixing the fixed plate on the lock; means for moving the movable plate; means for retaining the movable plate, configured to retain said movable plate once the latter has been moved by moving means; and alarm means configured to emit a sound and/or acoustic signal in the event of attempted tampering or forced opening of the lock
Although each of the different means described above will be explained later, from now on it is desired to place special emphasis on the alarm means, which in turn comprise: a micro-controller; a siren emitting an acoustic signal; electrical supply means to supply power to the micro-controller and the siren; lighting means to indicate the status of the system, which preferably comprise at least one light emitting diode, LED; a voltage converter to convert the supply voltage into a suitable voltage for the siren; and a trigger button, such that in the event of an attempted tampering or forced opening of the lock, the siren is activated.
Preferably, the micro-controller is power efficient and has a standard operating mode, also having a "watchdog" recovery circuit (better known by its Anglo-Saxon name "watchdog") that has a countdown clock to reset the system in case of locking.
Regarding the electrical power supply means, they are preferably based on a double supply consisting of a 3V battery to supply power to the micro-controller, and/or a 12V battery to supply power to the siren.
In relation to the voltage converter, it is preferably a switch converter, with 2.5V at the input and 12V at the output, with a maximum current consumption of 260mA.
Finally, with regard to the trigger button, it has been envisaged that it can be both a normally open button (NA), and a normally closed button (NC). However, it is preferably a button of the normally closed type.
In addition, the possibility has been provided for the security system to have video recording means, such that through a peephole coupled to the security system box itself, when the alarm goes off the person who is trying to force the lock can be recorded on the spot, said recording means preferably being connected to the internet to allow instant uploading of the video files to the cloud.
Therefore, the present invention provides a reliable, functional, simple and low-consumption solution for the protection of locks, preventing their manipulation and/or forced access by unauthorized third parties, also constituting a deterrent element. that alerts both visually and acoustically about the attempted manipulation and/or opening of the locks.

DESCRIPTION OF THE DRAWINGS

To complement the description that is being made and in order to help a better understanding of the features of the invention, according to a preferred example of a practical embodiment thereof, a set of drawings is attached as an integral part of said description wherein, for illustrative and non-limiting purposes, the following has been represented:

Figure 1.- Shows a side view of a lock provided with a security system, according to the current state of the art.
Figure 2.- Shows a perspective view of a lock provided with the security system object of the invention
Figure 3.- Shows the set formed by the fixed plate and the movable plate, on the side that is fixed on the lock.
Figure 4.- Shows the electronic diagram of the alarm means included in the security system of the invention.
Figure 5.- Shows a prototype where the assembly of the different component elements of the alarm means can be seen.

PREFERRED EMBODIMENT OF THE INVENTION

An example of a preferred embodiment is described below with reference to the figures cited above, without limiting or reducing the scope of protection of the present invention.
Figure 2 shows the security system of the invention, applicable to locks that comprise a box (1), a latch mechanism (2) housed inside the box (1), and a cylinder (3) that goes through the box (1) and has a key mechanism to actuate the latch mechanism (2).
Thus, according to a preferred embodiment of the invention, shown in Figures 2 and 3, the security system comprises:

a fixed plate (10), in this case located on one side of the lock,
a movable plate (20) supported on the fixed plate (11), shown in figure 3,
fixing means (30) of the fixed plate (10) on the lock,
moving means (40) of the movable plate (20),
Retention means (50) of the movable plate (20), which in the present preferred embodiment comprise a hook (51) configured to retain the movable plate (20) once the latter has been moved by the moving means (40), and
alarm means (60) configured to emit a sound and/or acoustic signal in the event of an attempted manipulation or forced opening of the lock.

In the exemplary embodiment of Figure 3, it is shown that the fixing means (30) of the fixed plate (10) comprise adhesive bands (31) arranged on the surface of the fixed plate (10) intended to be in contact with the lock.
For its part, the moving means (40) of the mobile plate (20) comprise a spring (41), represented in Figure 3, and which is fixed by one of its ends to the mobile plate (20), leaving said spring (41) in compression, loaded and ready to produce the movement of the movable plate (20) in case of removal of the cylinder (3) from the lock.
Turning now to Figures 4 and 5, they show the alarm means (60), which in turn comprise:

a micro-controller (61),
a siren (62) emitting an acoustic signal,
power supply means (63) to supply power to the micro-controller (61) and the siren (62),
Illumination means (64) to indicate the status of the system, and which in the present example of preferred embodiment comprise a light emitting diode, LED,
a voltage converter, not shown in the figures, to convert the supply voltage into a suitable voltage for the siren (62), and
a trigger button (66), such that in the event of an attempted tampering or forced opening of the lock, the siren (62) is activated.

For this preferred embodiment, a micro-controller (61) being power efficient and having a standard mode of operation has been chosen. Furthermore, the micro-controller (61) has a "watchdog" recovery circuit that has a countdown clock to reset the system in case of locking.
Such a "watchdog" recovery circuit is an essential part of the design. It is fixed when the program is recorded on the computer and cannot be overridden. In this state, the computer restarts every 18ms approximately. This time is far from the theorized 2 sec, so one of the first tasks of the firmware is to alter the time.
Preferably, the selected micro-controller (61) admits a supply voltage range between 2 and 5.5V.
More specifically, the micro-controller (61) has three pins configurable as input/output (I/O) and a fourth pin that can only be input (E). At the moment, two of these pins are required (one for the input and one for the output). Taking advantage of the fact that two others are available, additional functions can be added:

A pin for inhibition if the lock is going to be manipulated,
An LED output to indicate the status of the equipment.

Regarding the siren (62), so that its selection does not affect the rest of the design, the theoretical siren is an external element that is powered at the same voltage as the micro-controller (61) and that includes the necessary components to do it. The trigger cannot be direct (due to the low output current of the micro-controller) so a MOSFET (Metal-Oxide-Semiconductor Field-Effect Transistor) field effect transistor with the appropriate current is included, as shown in figure 4.
At this point it should be noted that said MOSFET transistor must have a gate voltage compatible with the microcontroller's power supply to guarantee a trigger under any condition.
The siren (62), due to its high acoustic level, will work at a high voltage, in the prototype shown in figure 5 a supply voltage of the siren (62) of 12V has been used. As part of the siren (62) a converter of adequate power and supply voltage to the siren voltage (62) has been designed.
In figure 5 it can be seen that the power supply means (63) are based, according to this preferred embodiment, on a double supply consisting of a 3V battery, made up of a pair of 1.5V alkaline batteries, to supply power to the micro-controller (61); and a 12V battery to supply power to the siren (62), made up of eight 1.5V alkaline batteries each. In this way, the power supply required has been simplified to adapt it to that of the micro-controller (61).
Indeed, in the example shown in Figure 5, the power supplies for the siren (62) on the one hand, and the micro-controller (61) on the other, have been separated. However, it has been foreseen that in the final equipment it can have a single power supply. Thus, it must be decided whether to use the simple 3V supply with a 12V converter for the siren or the 12V supply with a 3V converter with very low losses.
The duration of the 3V battery for supplying power to the micro-controller (61) is achieved by keeping it in a low consumption state most of the time, waking up periodically with the "watchdog" recovery circuit to check status and returning to low power mode.
A theoretical calculation allows a first approximation. The calculation is made based on the following parameters:

Watchdog cycle: 2 seconds
Reading / validating time: 10 ms

This gives us an estimated average consumption of about 30µA maximum, (also considering the leakage of the MOSFET transistor). With 1000mAhr AA alkaline batteries: $\frac{1000 mA . hr}{30 uA} \times \frac{1000 uA}{1 mA} \times \frac{1 day}{24 hours} \times \frac{1 year}{365 days} = 3, 805 days$
From the above, the estimated useful life under these conditions will be more than three years, which is appropriate for the project. It should be noted here that the above-mentioned useful life is without considering the alarm being triggered, since it has a high consumption.
Regarding the voltage converter, it has been foreseen that it is preferably a switch converter, with 2.5V at the input and 12V at the output, with a maximum current consumption of 260mA, for the XL-5530LW300-S-R model. Therefore, to work at 2.5V with a voltage converter that has an efficiency of 80% the current would be: $\frac{12 V}{2.5 V} \times 260 mA \times \frac{1}{80 %} = 1.56 A$
Regarding the trigger button (66), it is preferably a normally closed type button. Not for a trivial or random reason, but for a clear reason, that is, if in some case a third party manages to access the connection cables between the trigger button (66) and the micro-controller (61), cutting the cables activates the siren (62), triggering the acoustic alarm.

Input status measuring:

The input status measuring is performed several times to ensure that it is correct. An only instantaneous measurement implies a risk of detection of an electromagnetic noise. Thus, measuring is performed for 5 milliseconds and only if it is stable at this time, it is taken as valid.
During this time, if there are noises in the reverse direction, they are filtered out so that they are not taken into account. If the alarm condition has been detected, it goes to the alarm activation state. If not, the micro-controller goes back to sleep for the time remaining until it restarts two seconds later.

Alarm trigger:

If an alarm condition is detected, the program activates a trigger thereof, keeping the alarm activated for the time pre-set in the program (Currently 2 minutes). After this time of 2 minutes, the micro-controller turns off the siren and waits for the alarm condition to recover to return to its normal state. Another advantage of using a micro-controller is that the program can be modified so that the alarm is intermittent (which is more annoying), at different speeds or that it repeats from time to time..
At this point it should be noted that the current consumption with the alarm activated is very high for the chosen batteries. The duration of the activated alarm will be about 20 minutes before the batteries run out. Other stack formats ('C' or 'D') allow higher capacities.

Wake-up on pin change:

One of the problems that can be claimed as a failure in this design is the fact that there are 2 seconds between readings, and in these 2 seconds the equipment can be manipulated. In fact, it is not. Even if the micro-controller is in the "sleep" state to reduce the consumption, it can detect a change in the alarm input in this state and "wake up" so the response would also be immediate.

Mode of "operation":

This mode has been prepared to avoid the triggering of the alarm when the lock is legally intervened. A switch allows selecting the "operation" position, and in this case, the alarm does not go off even if the alarm situation is triggered.
It is a switch that is placed in one of the positions. When in the "operation" position the LED blinks faster (about four times per second). Consumption is low, but higher in this mode than in standard operating mode.

Assembly and operation of the pre-prototype:

The pre-prototype is mounted on a piece of printed circuit drilled with standard components. The final circuit can be fully assembled in surface assembly technology (SMD) for lower total mounting cost.

Consumption test:

The consumption test shows what was already expected in the theoretical analysis: Better results than the "worst" operating conditions.

Trip current test:

The current measured at 12V of the siren is 100mA (with the siren covered).

Signal distortion test on start and cut on siren:

There is no appreciable distortion in these maneuvers. The load does not appear to have significant inductive value.

Claims

Security system for locks, for application in locks that comprise a box (1), a latch mechanism (2) housed inside the box (1), and a cylinder (3) that passes through the box (1) and has of a key mechanism to actuate the latch mechanism (2), characterized in that said security system comprises:
- a fixed plate (10),

- a movable plate (20) supported on the fixed plate (10),

- fixing means (30) of the fixed plate (10) on the lock,

- moving means (40) of the movable plate (20),

- retention means (50) of the movable plate (20), configured to retain said movable plate (20) once the latter has been moved by the moving means (40), and

- alarm means (60) configured to emit a sound and/or acoustic signal in the event of an attempted manipulation or forced opening of the lock.
Security system for locks, according to claim 1, characterized in that the fixing means (30) of the fixed plate (10) comprise adhesive bands (31) arranged on the surface of the fixed plate (10) intended to be in contact with the lock.
Security system for locks, according to claim 1, characterized in that the moving means (40) of the movable plate (20) comprise a spring (41), fixed at one of its ends to the movable plate (20), remaining said spring (41) in compression, loaded and ready to produce the movement of the movable plate (20) in case of removal of the cylinder (3) from the lock.
Security system for locks, according to claim 1, characterized in that the retention means (50) of the movable plate (20) comprise a hook (51).
Security system for locks, according to claim 1, characterized in that the alarm means (60) comprise in turn:
- a micro-controller (61),

- a siren (62) emitting an acoustic signal,

- power supply means (63) to supply power to the micro-controller (61) and the siren (62),

- Illumination means (64) to indicate the status of the system,

- a voltage converter to convert the supply voltage into a suitable voltage for the siren (62), and

- a trigger button (66), such that in the event of an attempted tampering or forced opening of the lock, the siren (62) is activated.
Security system for locks, according to claim 5, characterized in that the micro-controller (61) is low consumption and has a standard operating mode.
Security system for locks, according to claim 6, characterized in that the micro-controller (61) also has a "watchdog" recovery circuit that has a countdown clock to reset the system in case of locking.
Security system for locks, according to claim 5, characterized in that the electrical power supply means (63) are based on a 3V battery to supply power to the micro-controller (61).
Security system for locks, according to claim 5, characterized in that the electrical power supply means (63) are based on a 12V battery to supply power to the siren (62).
Security system for locks, according to claim 8, characterized in that the 3V battery consists of a pair of 1.5V alkaline batteries
Security system for locks, according to claim 9, characterized in that the 12V battery consists of eight alkaline batteries of 1.5V each.
Security system for locks, according to claim 5, characterized in that the lighting means (64) comprise at least one light-emitting diode, LED.
Security system for locks, according to claim 5, characterized in that the voltage converter is a switch converter, 2.5V at the input and 12V at the output, with a maximum current consumption of 260mA.
Security system for locks, according to claim 5, characterized in that the trigger button (66) is a button of the normally closed type.
Security system for locks, according to any of the preceding claims, characterized in that it additionally comprises video recording means, such that through a peephole attached to the box (1) of the security system, when the alarm is triggered, the person who is trying to force the lock is recorded on the spot.