The invention refers to an industrial safety system, in particular for regulating the access of people into a protected area wherein an industrial machine operates.

To avoid accidents at work, safety regulations require the area adjacent to an industrial machine to be fenced and equipped with controlled access, so that when the industrial machine is running the area is clear of people.

Some known systems use e.g. lockable gates or barriers, and are based on key exclusivity. But experience shows that people's lack of caution goes so far as to lend the keys or duplicate them, so that someone has even remained locked inside the protected area while the machine was running.

Other known systems use e.g. video cameras, such as US20190180539. But even in this case there are incidents, either because the cameras are temporarily tampered with or because the watchers of the video circuit got distracted.

Then an infallible and foolproof security system would be needed.

Improving this state of the art is the main object of the invention.

A first aspect of the invention concerns a method to put under safety a protected area dedicated to the operation of an industrial machine, the area being equipped with a fence with an entrance, a movable barrier at the entrance (e.g. a gate or a lifting bar) for preventing or allowing transit through the entrance, a sensor of univocal biometric data, with the steps of

- detecting by the sensor a univocal biometric data (e.g. fingerprints or the pupil image) of a person,

- following the detection, opening the movable barrier to allow transit through the entrance,

- inhibiting the closing of the movable barrier until the or a univocal biometric data of the same person is detected again by the sensor.

This way it becomes impossible for the person entering the protected area to remain locked in there by mistake or accident.

To prevent a second person from being trapped in the protected area, in a preferred variant the method envisages detecting by the sensor a univocal biometric data of each person in front of the entrance, following the detection, opening the movable barrier to allow transit through the entrance, inhibiting the closing of the movable barrier until some or the univocal biometric data of all previously detected persons are detected again by the sensor.

To detect if there is one or more persons at the entrance, in a preferred variant the method envisages monitoring the area adjacent to the entrance with a sensor able to distinguish the number of present persons, e.g. a video camera, a proximity sensor, a load cell or infrared or ultrasound, and opening the movable barrier only when all detected persons have entered their biometric data through the biometric data sensor.

To increase safety, in a preferred variant the method envisages inhibiting the operation of the machine within the protected area until the biometric data sensor has detected some or the univocal biometric data of all previously detected persons or person.

To increase safety, in a preferred variant the method envisages detecting by the sensor a univocal biometric data of each person in front of the entrance, searching for the matching of the detected univocal biometric data in a database of authorized persons, refusing to open the movable barrier if the match is not found.

Another aspect of the invention is a safety system for a protected area dedicated to the operation of an industrial machine. The system comprises the area equipped with a fence with an entrance, a movable barrier at the entrance (e.g. a gate or a lifting bar) for preventing or allowing transit through the entrance, a sensor of a univocal biometric data, and an electronic processor configured for

• detecting by the sensor a univocal biometric data (e.g. fingerprints or the pupil image) of a person,

• following the detection, opening the movable barrier to allow transit through the entrance,

• inhibiting the closing of the movable barrier until the or a univocal biometric data of the same person is detected again by the sensor.

In general, the electronic processor may be configured to perform a or each step of the method.

In particular, the electronic processor is configured for detecting by the sensor a univocal biometric data of each person in front of the entrance, following the detection, opening the movable barrier to allow transit through the entrance, inhibiting the closing of the movable barrier until some or the univocal biometric data of all previously detected persons are detected again by the sensor.

Preferably, the protected area comprises a second sensor able to distinguish the number of present persons, e.g. a video camera, a proximity sensor, a load cell or infrared or ultrasound, and the electronic processor is configured to monitor the area adjacent to the entrance with the second sensor, and open the movable barrier only when all detected persons have entered their biometric data through the biometric data sensor.

To increase safety, in a preferred variant the electronic processor is configured to inhibit the operation of the machine within the protected area until the biometric data sensor has detected some or the univocal biometric data of all previously detected persons (or the person).

.To increase safety, in a preferred variant the electronic processor is configured to detect by the sensor a univocal biometric data of each person in front of the entrance, search for the matching of the detected univocal biometric data in a database of authorized persons, refuse to open the movable barrier if the match is not found.

The advantages of the invention will be clearer from the following description of a preferred embodiment of system, referring to the attached drawing in which - Fig. 1 shows a plan view of a safety area.

The safety system MC is used to monitor a work area 12 adjacent to a machine 10. The area 12 is fenced off by walls 20 and is accessible via an entrance 22 that can be closed by a gate 24.

Near the entrance 22 there is a fingerprint sensor 30 connected to an electronic control unit 40. In the electronic control unit 40 a program for the management of the transit at the entrance 22 is executed.

The operating logic is as follows. The gate 24 is normally closed.

The electronic control unit 40 constantly monitors if the sensor 30 has detected a univocal biometric data of a person P who wants to enter the area 12.

Following the detection, the electronic control unit 40 controls the opening of the gate 24 (by known means) to allow transit through the entrance 22.

Then the electronic control unit 40 activates the closing of the gate 24 only if the sensor 30 detects again the univocal biometric data of the same person P.

In the case of several persons entering, in a preferred variant the system comprises a sensor 42, connected to the electronic control unit 40, to monitor the area adjacent to the entrance 22 in order to distinguish the number of present persons P. For example, the sensor 42 is a video camera, a proximity sensor, a load cell or a infrared or ultrasound device.

The electronic control unit 40 is then programmed to detect through the sensor 42 how many people are in front of the gate 20, and control the opening of the gate 24 only if all the detected people have inserted their biometric data through the sensor 30.

After the electronic control unit 40 has commanded the opening of gate 24, it is programmed to command the closing of the gate 24 only if all the detected previously people have entered again their biometric data through the sensor 30.