EP2574718A2 - Safety system for safeguarding a moving, guided motion element against unwanted collisions - Google Patents

Abstract

The system (1) has an object-detection mechanism e.g. light sensor, blocked for object recognition by motion of a motion element (4). A shut-off unit transfers a part of the mechanism to a blocked state on detection of a shut-off signal e.g. light signal, coming from the element. A transmitter (12) either sits directly on the motion element or is attuned to a separate optical reflector on the motion element such that a signal of the transmitter is received by a receiver (9) of the shut-off unit only in a pre-defined area of motion of reflectors on the motion element.

Description

The invention relates to a security system for securing a particular vertically moving, guided movement element against unwanted collisions according to the preamble of claim 1.

State of the art

From the European patent EP 0 902 157 B1 it is known to secure gates with a light curtain, which is mounted in the plane of movement of a gate. So that the gate is not recognized as an object, monitoring beams of the light curtain are blocked by a respective past in the direction of movement of the gate monitoring beam for object detection when closing the gate before a leading edge of the gate detects the respective monitoring beam. In this way, the monitoring beams of the light curtain are successively no longer available for object recognition during a closing movement of the door.

In such an embodiment, however, it is conceivable that an object to be detected is mistakenly interpreted as an approaching gate and thus could cause an unwanted blocking of monitoring beams.

Purpose and advantages of the invention

The invention is based on the object to provide a safety system of the type described in the introduction, which can be locked depending on a movement of a moving member comparatively reliable for object detection.

This object is solved by the features of claim 1. In the dependent claims advantageous and expedient developments of the invention are given.

The invention is based on a security system for securing a moving, guided movement element, for. As a door or gate element, against unwanted collisions with a lying on a path of movement in the direction of movement of the moving object. The security system comprises an object detection device for detecting an object in a region of the movement element, which can be blocked by a movement of the movement element for object recognition, and an electronic unit, with which the movement of the movement element is controllable and which is adapted to the object detection device as the movement element approaches Assign lock state in which an object or motion element does not trigger a security mode. For this purpose, switch-off means are provided which, upon detection of a switch-off signal coming from the moving element, convert at least a part of the object detection device into the blocking state. The essence of the invention resides in the fact that the shut-off means comprise a transmitting device for a switch-off signal, which is tuned to a reflector for electromagnetic radiation, in particular optical reflector on the moving element, in such a way that of a receiver of the shutdown means only in a predefined range of motion of the reflector on the moving element, a signal of the transmitting member can be received. According to the invention, the object detection device and / or the shutdown means are / is distance sensors, in particular as time-of-flight sensors educated. By means of this procedure it can be avoided that a reflection of an object is interpreted as a switch-off signal and thus a shutdown of the object detection device or at least a part thereof takes place by mistake,

The security system according to the invention can in particular at gates, z. B. Rolltoren or doors, z. B are used in sliding doors as in pull-outs. Other applications can be in the field of machines, z. B. presses are.

Since it is necessary for a signal from the movement element to be received directly to block at least a part of the object detection device, it can be achieved that objects in the door region can not trigger such a blockage since such objects normally do not emit corresponding signals.

In contrast to the embodiment of the EP 0 902 175 B1 A lock is not due to an interruption of a beam, but by the recognition of a specific signal coming from the gate element, which is regularly different from signal reflections on objects. This makes the locking process much safer.

Optionally, the object detection device is completely switched off by the disconnection means.

In a particularly preferred embodiment of the invention, the object detection device comprises a curtain of a plurality of object detection means arranged one after the other in the direction of movement of the movement element. When switched off by the approaching movement element, the object detection means closest to a front edge of the movement element is preferably blocked for object recognition.

Furthermore, it is particularly preferred if the shut-off means are designed to use a shutdown signal as to evaluate such only if it comes in a predetermined period of time during the movement of the moving element. As a result, the shutdown safety is further increased. For the probability that, firstly, a signal fulfills the conditions to be scored in principle as a shutdown signal and secondly still occurs in a predicted time window, is highly unlikely. The predicted time star can be z. B. determine that can be predicted due to a known speed of the moving element and a known geometric arrangement of the shutdown, at which time the moving element must appear at a predetermined location of the shutdown.

Thus, the probability increases significantly, the object detection device in approaching motion element, eg. B. gate element, properly assign a blocking state in which an object or the moving element in the object detection device does not trigger a security mode, the z. B. stops the movement element and / or reversed.

A reflector in the signal path of the cut-off means is advantageous because a reflector reflects light much better than a conventional object to be detected, so that it is possible to work with comparatively low light output at the cut-off means. In addition, a misinterpretation of a reflection from a detecting object can thereby be precluded if only defined directed and / or acquired light is used for the evaluation.

The movement of the element, for. As a door, a gate or other moving guided component coming shutdown signal may be a sound and / or light signal and / or electromagnetic or magnetic nature. It can also be used polarized light, which further increases the noise immunity.

It is conceivable, for example, that sent electromagnetic radiation, for example light, is provided by a modulator having a predetermined characteristic, the modulated light being tuned to an analyzer located in front of the receiver in such a way that only the modified, modulated light can be received. By doing so, the security in signal detection increases significantly. For example, light is changed via a polarizing filter or retarder plate in a predefined manner. The receiver is designed so that it can only receive the changed light. For example, the emitted light is linearly polarized, with a reflector changing the polarization characteristics in a manner to strike the receiver with circularly polarized light. The circularly polarized light can be evaluated at the receiver.

Also by appropriate selection of the type of signal depending on the location of the gate can be excluded that there is misinterpretation when locking object detection means of the object detection device, because e.g. a reflection from an object is misinterpreted by a sensor of the object detection means.

In a particularly preferred embodiment of the invention, the shut-off means in the region of a guide rail of the movement element comprise a transmitter or receiver which form the shut-off means together with a receiver or transmitter of the object detection device. By this measure, the backup system can be designed inexpensively, since existing elements of the object detection device for the shutdown means are used. For example, receivers and their evaluation are comparatively expensive. Accordingly, it is advantageous that the disconnection means use the existing receivers of the object detection device, but optionally have additional transmitters, so that with the help of the transmitter, a signal on the moving element, thus coming from the moving element, directed to the existing receiver and evaluated there, to lock at least a part of the object detection device cause.

In this case, not every object detection means of the object detection device has to be assigned a transmitter. It is conceivable that a transmitter cooperates with a plurality of receivers of the object detection means, for example, object detection means are passively switched in blocks or disabled or completely switched off. It is also conceivable that a transmitter of the shutdown means is assigned only to individual receivers of the object detection means, wherein a shutdown of further, in particular in the closing direction of the moving element subsequent object detection means without an associated transmitter is carried out via an algorithm, e.g. by means of a speed calculation.

In a further preferred embodiment of the invention, the shut-off means are adapted to a completely closed state of the moving element, for. B. determine a gate element. It can e.g. be evaluated in the closed position of the gate element, a signal from the gate element, which must be received permanently in this position. A gate control, the detected closed position can be provided.

In this context, it is also preferable if an interface is provided to output or read in the current position of the movement element. If the possibility arises of transmitting the end position of the movement element to the control, then e.g. To check if the movement element behaves properly. If z. 8. a door pressed by wind power from the intended path, which is not excluded in flexible rolling doors, the controller can be transmitted a corresponding signal, for example, a stop signal.

In principle, the object detection means need not be arranged equidistantly along the movement path of the movement element. For example, in the end area, eg floor area, a distance of 5 cm and in the remaining area of 20 cm realized. Thus, smaller objects can still be reliably detected, in particular in the bottom area of a door. Overall, however, it is not necessary for a large sensor density to be realized over the entire height of movement of the movement element.

Furthermore, it is advantageous if elements of the cut-off means, which are fastened to the movement element, have a predetermined distance to the front edge. Because the leading edge of moving elements, e.g. Gate elements, is usually not suitable for attachment of objects. It is usually soft, on the one hand sufficient to close a gap between the door element and a ground level, on the other hand, the risk of injury in unwanted collisions is reduced.

So that the signals of the object detection device can be blocked in time, it is proposed that receivers of the disconnection means are arranged offset relative to receivers of the object detection device.

1. a) Der Öffnungswinkel von eingesetzten Optiken wird insbesondere gemäß einschlägiger Norm gewählt.
2. b) Die Signalkette wird überwacht, z.B. indem die Anzahl von für die Objekterkennung aktiven Objektdetektionsmitteln überwacht wird.
3. c) Schaltausgänge der Objektdetektionsmittel werden beispielsweise mit einem Testeingang zur Ausführung von Testprozeduren versehen.
4. d) Außerdem können "Online-Tests" implementiert sein, in der Art eines ROM-Checks, der während eines Betriebs kontinuierlich ausgeführt wird.

To obtain a further improvement of the functional safety of the security system, the following measures are conceivable:

1. a) The opening angle of inserted optics is chosen in particular according to the relevant standard.
2. b) The signal chain is monitored, for example by monitoring the number of object detection means active for the object recognition.
3. c) switching outputs of the object detection means are provided for example with a test input for carrying out test procedures.
4. d) In addition, "online tests" can be implemented, in the manner of a ROM check, which is carried out continuously during operation.

The individual components of the security system on one side of a movement element need not necessarily be accommodated in a structural unit. It is conceivable that e.g. Individual sensor pairs or groups of sensors are communicated via a bus communicating. This makes it possible to achieve greater flexibility if the object detection device and / or switch-off means of the security system are to be adapted to different structural conditions, in particular smaller or larger surveillance areas.

The sensors can then be selected depending on the power profile required at the respective door element.

characters

Figuren 1 - 3

einen Ausschnitt eines Torelements sowie eines Torsicherungssystems an einer Seite des Torelements in jeweils einer schematischen Darstellung für unterschiedliche Ausgestaltungen von Abschaltmitteln, die ein Sperren von Überwachungslichtstrahlen einer Lichtschrankenanordnung für die Objekterkennung bewirken,

Figur 4 und 5

Möglichkeiten von Reflexionsmitteln, die Teil eines Signalwegs von Abschaltmitteln sind, in jeweils schematischen Ansichten und

Figur 6

einer perspektivischen Ansicht ein Reflektor für Abschaltmittel.

Several embodiments of the invention are illustrated in the drawings and will be explained in more detail below, indicating further advantages and details. Show it

Figures 1 - 3

a detail of a gate element and a Torsicherungssystems on one side of the gate element in each case a schematic representation of different embodiments of shutdown, which cause a blocking of monitoring light beams of a light barrier arrangement for the object recognition,

FIGS. 4 and 5

Possibilities of reflection means, which are part of a signal path of cut-off means, respectively in schematic views and

FIG. 6

a perspective view of a reflector for shutdown.

Description of the embodiments

In the Figures 1 - 3 in each case the left side of different Torsicherungssystemen 1, 2, 3 shown. From a gate element 4, the lower left corner is shown schematically in each case. The Torsicherungssysteme 1, 2, 3 comprise on the left side in each case a receiver strip 5, 6, 7. The associated transmitter, send out the monitoring light beams 8 to a respective receiver 9, are in the Figures 1 - 3 not to be seen. The monitoring light beams 8 ensure that when an object enters an area 10 below a front edge 4a of the door element 4 due to an interruption of the monitoring light beams 8, the gate element 4 stops, g reverses to prevent collisions with the object.

When shutting down the gate element 4, however, it must be ensured that the gate element 4 does not itself trigger a safety mode because the gate has interrupted a monitoring light beam 8. This can be achieved by bringing a respective transceiver pair for generating the monitoring light beam into a passive state which no longer triggers the safety mode before the respective monitoring light beam 8 is reached by the front edge 4a of the door element 4 during movement of the gate element 4 in a movement direction 11.

In the Figures 1 - 3 this happens in different ways:

In FIG. 1 is in the left front area of the gate element 4, a transmitter 12 is positioned. The transmitter 12 cooperates with receivers (not shown) which, in principle, could also be the receivers 9, whereby the monitoring light beams 8 for the object recognition are successively blocked when the door element 4 is shut down. The locked monitoring light beams are in the Figures 1 - 3 shown in dashed lines. The transmitter 12 preferably cooperates with the receivers such that, before reaching a Monitoring light beam 8 through the front edge 4a of the gate element, a respective receiver detects that the gate element is in this position by a signal emitted by the transmitter 12, whereby the respective receiver transmitter pairing for the monitoring light beam is set in a passive state.

Preferably, the receivers of the turn-off means are arranged offset to the receivers for the respective monitoring light beams 8.

In FIG. 2 The same receivers of the detection means are also used for the shutdown. In order to allow a timely shutdown of the first beam 8, is in FIG. 2 an additional receiver 9a is provided which evaluates light from an additional transmitter 13 in order to block the monitoring light beam 8a following in the direction of movement 11 or to bring the associated receiver transmitter pair into a passive state with respect to the object evaluation. The signal of the additional transmitter 13 is directed via a reflector 15 to the receiver 9a. The reflector 15 is seated on the gate element 4, so that in this way the presence of the gate element can be reliably detected. As the gate element 4 advances in the direction of movement 11, further additional transmitters 14 then cooperate with staggered receivers 9 in order in each case to obtain the blocking of the monitoring light beams.

In FIG. 3 the turn-off means comprise a single transmitter 16, which reflects light to already existing receivers 9 via the reflector 15 mounted on the gate element 4. As soon as a receiver 9 detects a signal coming from the transmitter 16, this receiver 9 and a corresponding transmitter on the other side of the door is locked in the event of object recognition, so that the safety mode is not triggered when the front edge 4 a Signal path between this sensor pairing interrupts.

In principle, it is conceivable that a transponder system is also used for gate recognition, with a transponder being mounted on the gate element. For example, an RFID system can be used with a transponder on the gate element. The transponder may be passive, i. he does not have his own energy supply. When using an RFID on the moving element, e.g. a gate, the position of the gate can be determined by triangulation. For example, an RFID receiver is provided at the upper end and at the lower end on the path of the gate.

It is important that the signal path with shutdown means 12, 13, 14, 15, 16 is subjected to as few disturbances as possible. This can for example be achieved by a reflector 15 on a gate element, as in FIG. 4 has only a small reflection lobe, which should be illustrated by the arrows 17a-17e. This ensures that the possibility of a beam cut-off by stray light is practically impossible even to the next receiver of the shutdown.

Instead of a reflector 15, which is mounted more or less open, a type of light guide 18 can be used, which has a defined receiving lobe 19 and a defined transmitting lobe 20 on a transmitter 21 and with respect to a receiver 22, so that also a misinterpretation of signals can practically no longer take place (see FIG. 5 ). In the signal path can be as in FIG. 5 shown a collimation device are used, for. As a lens 22 a, which makes it even more difficult that a reflection of light from the transmitter 21 takes place to the receiver 22, which is interpreted as a shutdown signal. For further light beam definition, as in Fig. 5 also shown, in particular in the light path from the transmitter 21 to the light guide 18, a diaphragm 22 b may be provided.

In addition, a modulator after transmission 21 and an analyzer in front of the receiver 22 can be arranged in the light path, which further increases security.

In FIG. 6 a reflector 27 is shown.

The reflector 27 is z. B. a massive polyhedron of a translucent, especially crystal clear material. According to FIG. 6 occurs z. B. on a surface 28, a light beam 29 in the reflector 27 and is then mirrored by total reflection at the surface 30, further to the surfaces 31 and 32, where also total reflection takes place, so that the light beam 29, the reflector 27 over the surface 28th leaves again.

The specialty of this reflector is that an incident light beam 29a is offset only by a certain distance compared to the outgoing light beam 29b. The direction of the incident light beam 29a to the emergent light beam 29b remains unchanged. If several such reflectors arranged side by side, light z. B. emitted from a point source, reflected to an offset point. By this reflector can thus light, z. B. are reflected to a receiver, which additionally has a predetermined direction with the desired light intensity.

This further enhances the security of the system, as it is unlikely that false reflections will be interpreted as actually reflected shutdown signals.

LIST OF REFERENCE NUMBERS

1

Torsicherungssystem

2

Torsicherungssystem

3

Torsicherungssystem

4

gate element

4a

leading edge

4b

front

5

receiving end

6

receiving end

7

receiving end

8th

Monitor light beam

8a

Monitor light beam

9

receiver

9a

receiver

10

Area

11

movement direction

12

transmitter

13

transmitter

14

transmitter

15

reflector

16

transmitter

17a

light rays

17b

light rays

17c

light rays

17d

light rays

17e

light rays

18

optical fiber

19

transmission lobe

20

reception lobe

21

transmitter

22

receiver

22a

lens

22b

cover

27

reflector

28

area

29

beam of light

29a

incident light beam

29b

failing light beam

30

area

31

area

32

area

Claims (8)

Securing system (1, 2, 3) for securing a moving, guided movement element (4) against unwanted collisions with an object lying on a movement path in the direction of movement (11) of the movement element (4), which device comprises an object detection device for detecting an object in an area of the movement element (4), which can be blocked by a movement of the movement element (4) for an object recognition, and an electronic unit with which the movement of the movement element (4) is controllable and which is adapted to the object detection device when the movement element approaches ( 4) to assign a blocking state in which an object or moving element does not trigger a safety mode, wherein disconnection means (12, 13, 14, 15, 16, 18) are provided which upon detection of a coming from the moving element (4) shutdown signal at least a part of the object detection device into the locked state, thereby gekennzei Chnet, that the shut-off means comprise a transmitting device for a shutdown signal, which is tuned to a reflector for electromagnetic radiation, in particular optical reflector (15, 27) on the moving element (4) in such a way that of a receiver of the shutdown means only in a predefined range of motion the reflector (15, 27) on the movement element (4), a signal of the transmitting member can be received and wherein the object detection device and / or the shutdown means is designed as a distance sensor, in particular as a time-of-flight sensor / are. System according to claim 1, characterized in that the security system is a door / gate system. System according to claim 1, characterized in that the object detection device comprises a curtain of a plurality of object detection means arranged one after the other in the direction of movement of the movement element. System according to one of the preceding claims, characterized in that the cut-off means are adapted to evaluate a shutdown signal as such, only if it comes in a predetermined period of time during movement of the moving member from the moving member. System according to one of the preceding claims, characterized in that the switch-off signal is a signal based on light, sound, electromagnetic radiation and / or a magnetic field. System according to one of the preceding claims, characterized in that in the region of a guide strip (23) of a movement element (4) the shutdown means comprise a transmitter (13, 14) or receiver, which together with a receiver (9) or transmitter of the object detection means the shutdown form. System according to one of the preceding claims, characterized in that the shut-off means are adapted to determine an end position, in particular a completely closed state of a moving element (4). System according to one of the preceding claims, characterized in that object detection means are not arranged equidistant in the direction of movement of the moving element.

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