EP1529913A2

EP1529913A2 - Safety system for automatic gates

Info

Publication number: EP1529913A2
Application number: EP04078067A
Authority: EP
Inventors: Gianni Michielan
Original assignee: Fin-Men SpA
Current assignee: Fin-Men SpA
Priority date: 2003-11-10
Filing date: 2004-11-09
Publication date: 2005-05-11
Also published as: ITMI20032161A1; EP1529913A3

Abstract

Safety system for an automatic gate, which has a protective rib suitable for generating a detection signal of the contact of a door of the gate with an obstacle. The system has an infrared transmitter, associated with said door, activated by a pilot circuit that receives the signal of said rib and is suitable for sending an infrared signal in the direction of an infrared receiver associated with the fixed part of the gate.

Description

The present invention refers to a safety system for automatic gates.

The gate to which the system of the present invention can be applied can be a sliding gate, a swing gate and, more generally the system of the present invention can be applied to barriers in which the access point is opened and closed by at least one door moved automatically.

Automatic gates for gaining access to private areas are usually actuated by the users, at fixed control points, through buttons or keys for opening and closing or by means of remote controls, which send a radio impulse to an electronic control station, which takes care of actuating the gate in the desired direction.

Moreover, generally, in the case of remote radio transmissions, after having commanded the gate to open, its subsequent closing takes place through the sending of another command by the user or else it takes place automatically after a certain predetermined period of time.

These types of sliding gates, however, can become the source of serious drawbacks, from the point of view of the safety of the user, since, due to the intrinsic configuration of the structures, they usually comprise moving parts, which have sharp edges that are very dangerous to the user's well-being.

Indeed, since these gates are actuated remotely from fixed control stations, the movement of the structure cannot be interrupted automatically at the moment of collision of potential users or of other objects against projecting portions of the aforementioned structures, in particular against the primary edge, other than by manually interrupting the power supply of the system at a time after that when it was really needed.

Consequently, one can imagine the inevitable and sometimes dramatic consequences linked to the slow speed with which such a type of intervention can be carried out.

In order to brake or interrupt the stroke of a moving automatic gate, in the case of imminent danger, without needing to intervene manually, safety systems for sliding gates, substantially based upon the use of protective ribs, have been used.

Such ribs are positioned at the most dangerous edges, they are made from soft material and transmit, for example by means of manostats, an electric signal to a contact of an electronic transmitter whenever the pressure inside them varies, for example in the case of contact and accidental collisions caused by vehicles as they pass.

Indeed, when the vehicle bumps into the rib, the electronic transmitter immediately sends an impulse to a receiver, which can be activated through radio contact, which is located separately around a fixed point and that immediately takes care of interrupting the power supply to the system; consequently, if the gate is moving, it instantly locks in the position reached.

As an alternative to pneumatic ribs, there are ribs again made from soft material, which contain a taut steel cable inside them, which connects a contact of an electronic transmitter by means of leverisms, whenever the tension of the cable increases by a predetermined value, for example through a microswitch. The microswitch takes care of interrupting the power supply to the system.

In this way, any contact or accidental collision against the rib causes the instant locking of the gate in the position taken up at the moment of contact.

In the case of automatic sliding gates, the protective rib is mounted, through the application of an aluminium shaped profile, on the front surface in the direction of movement of the sliding door of the gate itself.

The transmission of the signal generated by the protective rib to a control station of the gate is a transmission that takes place via radio, or else it is a transmission that takes place via cable from the sliding door to the fixed part of the gate, through flexible electric cables or through sliding trolleys on the gate.

The Applicant has observed that each of the known methods for the transmission of a signal to the rib has reliability problems. For example, the interruption signal transmitted via radio from the ribs to the control station of the gate can suffer from disturbances such that it may not be perceived and therefore recognised by the control station. An interruption signal transmitted via cable determines the need to lay cables between a fixed part and a mobile part of the gate with a consequent possibility of breaking and/or damage in time.

The Applicant has found a simple and reliable way to carry out such a transmission of the signal of the rib, which uses a connection, determined by an infrared signal, between the fixed part and the moveable part of the gate. In particular, a connection is always kept active between the fixed part and the mobile door of the gate, generated by an infrared transmitter and received by a corresponding receiver; an intervention signal of the rib, due for example to a collision against an obstacle of the rib itself, deactivates the infrared transmitter and generates an interruption of the connection between the mobile part and the fixed part of the gate. Such an interruption is received by the control station of the gate that interrupts the moving gate itself.

An aspect of the present invention concerns a safety system for an automatic gate, said gate comprising a mobile door, suitable for covering an access space defined at the ends on fixed sides of said gate, which has a protective rib suitable for generating a detection signal of the contact of the mobile door with an obstacle, characterised in that it comprises a device for generating an infrared signal describing a state of correct operation of the gate and the lack of reception of said signal resulting in the stopping of the movement of said door.

The characteristics and the advantages of the safety system for automatic sliding gates according to the present invention shall become clearer from the following description, given as an example and not for limiting purposes, referring to the attached schematic drawings, in which:

figure 1 is a perspective view of an automatic sliding gate, with which the safety system according to the present invention is associated.
figure 2 is a schematic view of the safety system according to the present invention.

With reference to the quoted figures, the automatic gate comprises a sliding door 10, illustrated as an example in the figures as being rectangular in shape, which slides inside a guide 11 fixed on the ground and covers and access space. Such an access space is defined at its ends by fixed parts of said gate that comprise a post 12, annexed for example to a wall 13, and an upright 14.

The sliding door is moved inside said guides by a motor, for example an electric motor.

In the example embodiment shown in figures 1 and 2, the sliding door 11 is provided with a protective rib 15, made from rubber or in any case from a soft material, being substantially in the shape of a triangular prism and associated with a front wall of said door.

For the purposes of the present invention the protective rib can be made according to different technologies that are equivalent to each other, which, at a pressure applied on the soft material of said rib, generate a signal or interrupt an electric signal, so as to indicate that a collision of the rib against an obstacle has occurred and that the movement of the sliding door should be stopped.

The gate is moved by said motor, which is controlled by an electronic control unit situated close to the fixed parts of the gate.

As an example, the rib 15 illustrated in figures 1 and 2 is of the cable type; in particular, inside the rib 15 runs a cable, for example made from steel, arranged vertically, immediately below the rubber surface of the rib.

Said rib is also provided with a microswitch system, preferably arranged on the top of the rib itself, mechanically connected to said cable and able to be activated by it in response to a traction of the cable, for example caused when pressure is exerted on the soft material of said rib.

The safety system according to the present invention uses the alarm signal generated by the microswitch inside the rib to communicate a state of alarm or a state of correct operation of the rib itself.

The state of alarm identifies a condition in which there has been a collision of the sliding door against an obstacle during its movement, or else it can identify an operating anomaly of the rib such as to require the interruption of the operation of the gate as a whole.

For such a purpose, the safety system comprises a transmitter 16, situated on the top of said sliding door 10, preferably associated with the head of the protective rib 15, and a receiver 17 situated on the fixed parts of the gate, for example close to said post. Such a transmitter and such a receiver are arranged with respect to each other so that an infrared signal transmitted by said transmitter can be received by said receiver. In particular, the transmitter is an infrared receiver and the receiver is an infrared receiver. Moreover, the transmitter and the receiver are preferably aligned with each other on the top of said gate.

The infrared transmitter 16 is actuated by a pilot circuit (not shown in the figures) comprising a microprocessor, which activates or deactivates the transmitter itself based upon the electric signal received by said protective rib. Moreover, such a transmitter and the pilot circuit are supplied with power by a long-life battery.

In the example embodiment shown, the microswitch actuated by the cable of said rib is connected with said pilot circuit.

Moreover, said receiver 17 is connected to a decoding circuit connected to the electronic control unit of the gate.

Said pilot circuit is suitable for keeping the transmitter active during the normal operation of the gate, through the sending of a predetermined infrared signal, whereas, following a change in the signal of the rib it deactivates the infrared transmitter, identifying a state of alarm. The decoding circuit receives the state of alarm following the lack of reception of the infrared signal and sends a locking signal to the control unit of the gate that stops the motor and the movement of the gate itself.

This very simple system allows the risks of improper operation of the safety system to be reduced to the minimum. For example, in the case in which for whatever reason the pilot circuit or the infrared transmitter are unable to operate correctly, the gate is stopped. In the same way, the gate is stopped in the case in which the signal cannot be correctly transmitted by the protective rib, or in the case in which an obstacle is positioned between the infrared transmitter and the infrared receiver.

Moreover, the transmitter is preferably supplied with power by a battery, which needs to be replaced regularly; for such a purpose, the system of the present invention comprises a circuit for indicating the charge of the battery, which foresees the presence of an indicator light of the charge of the battery situated close to said receiver.

For such a purpose the pilot circuit of the transmitter encodes the infrared signal inserting inside it the information on the state of the battery. The decoding circuit can decode such information contained in the infrared signal and activate said light for indicating the state of the battery.

In particular, the pilot circuit can encode the infrared signal by inserting regular impulses a predetermined distance apart from each other. In the case in which the battery starts to run out the pilot circuit can intensify or reduce the frequency of said impulses. In such a way the decoding circuit on the receiver can activate the indicator light at such a variation in frequency of the impulses. A suitable adjustment of the system can adjust the switching on of the empty battery light sufficiently in advance of the actual empty battery condition (for example two or three months before).

Preferably, such an indicator light is on the receiver, since it can easily be supplied with power by the electronic control unit of the gate, ensuring that the electronic circuits contained in the pilot circuit that commands the transmitter is reduced to the minimum.

Alternatively, such a light can be placed directly on the transmitter.

Although the example embodiment described refers to a gate having a sliding door, the system of the present invention can equally be applied to gates or front doors in which the door moves in a different way, provided that the infrared transmitter and receiver are always aligned with each other, so as to allow the correct communication between them. Moreover, in the illustrated example the transmitter is associated with the mobile door of the gate and the receiver is associated with the fixed part of the gate. In an equivalent manner, the present invention could arrange both the transmitter and the receiver on the fixed part of the gate and associate a reflector with said protective rib positioned so that the infrared signal transmitted by the transmitter is reflected by the reflector in the direction of the receiver. In this case, an intervention of the protective rib, for example due to a collision against an obstacle, could prevent the reflection and therefore the connection of the infrared signal between the transmitter and the receiver. In general, the present invention refers to the generation of an infrared signal, which places the mobile door, and therefore the protective rib, in communication with the control station and therefore the fixed part of the gate.

Therefore, in this embodiment the present invention comprises a device for generating an infrared signal that comprises an infrared transmitter, receiver and reflector. In the embodiment illustrated in the attached figures the generation device of the present invention, however, comprises just one infrared transmitter and receiver.

In all cases, however, the infrared signal describes a state of correct operation of the gate and the lack of reception of said signal results in the stopping of the movement of the mobile door of the gate.

Claims

Safety system for an automatic gate, said gate comprising a mobile door, suitable for covering an access space defined at the ends on fixed parts of said gate, which has a protective rib suitable for generating a detection signal of the contact of the mobile door with an obstacle,
characterised in that it comprises
a device for generating an infrared signal describing a state of correct operation of the gate and the lack of reception of said signal resulting in the stopping of the movement of said door.
System according to claim 1, wherein said device for generating a signal comprises an infrared transmitter, associated with said mobile door and activated by a pilot circuit that receives said detection signal from said rib and is suitable for sending an infrared signal in the direction of a corresponding infrared receiver associated with said fixed part of the gate.
System according to claim 1, wherein said device for generating a signal comprises an infrared transmitter and receiver situated on the fixed part of said gate, a reflector situated on said door suitable for reflecting the signal emitted by said transmitter towards said receiver, said reflector being activated and deactivated according to the detection signal of said rib.
System according to claim 2, wherein said infrared transmitter is arranged on the top of said door.
System according to claim 2, wherein said transmitter and said receiver are aligned with each other on top of said gate.
System according to claim 2, wherein said pilot circuit deactivates the transmitter upon the reception of said detection signal of the contact of the mobile door with an obstacle.
System according to claim 2, wherein said transmitter and said pilot circuit are supplied with power by a battery.
System according to claim 1, wherein said receiver is connected to a decoding circuit associated with a control unit of the gate.
System according to claim 2, comprising an indicator light of the state of charge of said battery arranged close to said receiver.
System according to claim 2, comprising an indicator light of the state of charge of said battery arranged close to said transmitter.