EP3584400B1 - Safety door and method for operating a safety door - Google Patents

Description

The present disclosure relates to a protective device in the form of a protective door or gate. In particular, the present disclosure relates to so-called machine protection gates and/or machine protection doors. Such protective devices are used, for example, to securely close access to machines and systems and to release them if necessary.
From the post-published WO 2019/162447 A1 a method for operating a door system is known, with at least one actuatable door element, at least one door drive for opening and closing the door element and a control unit for controlling the door drive, with a surveillance area in front of the door element being recorded by means of at least one stereoscopic camera system, with object recognition the control unit detects objects in the monitored area by evaluating the camera recordings and controls the door element taking into account a detected object in the monitored area. The monitoring area is divided into a restricted area and a warning area in front of the restricted area. The detection of an object in the restricted area or warning area triggers different actions.
From the DE 10 2015 101 017 A1 a method for controlling a door arrangement is known, with a door leaf which is guided laterally in guides and driven by a drive device between an open and a closed position in a door closing plane of a door opening and can be moved back and forth, the door arrangement having a Has a safety device that monitors a monitoring area that is offset parallel to the door closing level in front of the door opening, and executes a fault routine if an object is detected in the monitoring area and there is a risk of the object colliding with the door leaf. The safety device has a light grid system arranged in a vertical plane, which has light barriers at a first distance from one another in a first section and light barriers at a second distance from one another in a second section, which is smaller than the first distance. Accordingly, smaller objects can be detected in the second section than in the first section.

in particular, the present disclosure relates to so-called high-speed gates and doors. This generally includes gates and doors that have a closing speed of more than 0.5 m/s. However, this is not to be understood as limiting.

Furthermore, the present disclosure relates, at least in exemplary embodiments, to so-called industrial doors, ie to doors for industrial use. For example, such a goal can have a width of 2.50 m and a height of 3 m. However, this is also not to be understood as limiting. Doors and gates to which the present disclosure relates are provided with a drive to open and close.

There are vertically closing doors and gates and horizontally closing doors and gates. The closing elements (comparable to a door leaf) can have a plurality of (inherently) rigid segments/links, a web that can be wound up and/or an armor that can be wound up. Combinations of these are also conceivable.

Doors and gates in the industrial environment are subject to various safety regulations, such as the so-called accident prevention regulations. When operating a door, various scenarios are conceivable that must be avoided at all costs. One scenario is the collision of an object with the closed gate. Another scenario is an object being trapped by a closing gate. Both Scenarios can lead to production downtime, damage and even health problems.

Against this background, safety devices are prescribed in the industrial environment, which in particular monitor a closing gate/door in order to prevent entrapment and/or other collisions with moving parts of the gate. At least for certain applications, it is prescribed to monitor a so-called closing edge of the closing gate for collisions and/or impending collisions. In the event of an undesirable condition (an alarm), the gate should be reopened as soon as possible. This process is called reversing.

It is not uncommon for the safety devices to be functionally and, if necessary, also structurally independent of other devices for operating the door. In this way, a certain redundancy can be provided.

In this way, collisions and the corresponding consequential damage can be effectively avoided. However, it has been shown that a large number of alarms, which can regularly include a not inconsiderable number of false alarms, can lead to a reduction in productivity.

Current processes/manufacturing steps are frequently interrupted and emergency stop routines may even be carried out, particularly when an alarm condition is detected and the door reverses as quickly as possible. This regularly leads to significant delays and unproductive times. This can lead to cycle times increasing.

Against this background, the present invention is based on the object of specifying a protective device in the form of a protective door or a protective gate for a plant, which enables high productivity and in particular reduces downtimes and/or alarm times due to false alarms. The protective device should nevertheless comply with applicable safety regulations. The protective device should be safely operable. The protective device should enable rapid operation, ie high closing speeds, of the gate or door.

Furthermore, within the scope of the present invention, an advantageous use of a protective gate is to be specified. Furthermore, within the scope of the present invention, a method for operating a protective device in the form of a protective door or a protective gate is to be specified.

Regarding the device, the object of the invention is achieved by a protective device in the form of a protective door or a protective gate for a plant, in particular a production plant, according to claim 1 .

The object of the invention is completely achieved in this way.

According to the invention, the control device now differentiates between at least two states in which there is a potential risk of collision. In the first distance range, which is a close range, for example, a corresponding alarm is issued immediately, so that the gate/door—more precisely, the respective closing element—can quickly stop and reverse. In contrast, in the second spacing region, which is in front of the first spacing region, the closing element is not yet stopped or reversed. Instead, the speed of the closing closing element is reduced somewhat, so that, for example, when the foreign object penetrates into the first distance range, the closing element can still be stopped and reversed safely.

The first operating mode is associated with the first distance range and the second operating mode is associated with the second distance range. Accordingly, the first operating mode is a stop and reverse mode. Accordingly, the second mode of operation is a reduced speed mode. It goes without saying that there can also be a normal operating mode (normal operating mode) in addition to the first operating mode and the second operating mode. The drive is in normal operating mode when the closing element closes operated if no foreign object was detected in the monitored safety zone.

At least in exemplary configurations, the closing element is monitored primarily during the closing process of the protective device. In other words, at least in these exemplary configurations, the monitoring device is not used for regular opening processes during normal operation of the protective device. Additional facilities are provided for this purpose.

At least in this embodiment, the monitoring device and the control device form a safety device that is provided in addition to other control elements, sensors, interfaces and the like. It goes without saying that the control device can also be used to control other functions in addition to the safety function. However, it is also conceivable to provide a separate control device for the safety device, which can basically be operated independently of other control elements.

The protective device is preferably used as a protective machine gate or protective machine door. The upstream connection of the second distance range enables, so to speak, an early detection of an impending collision, without this necessarily leading to the closing element stopping and reversing. At the same time, there is a high level of security against pinching and collisions.

When used as a machine guard gate or machine guard door, the guard regularly monitors one side (usually the outside) of the two sides (inside, outside) that are interconnectable through the guard. It goes without saying that applications are also conceivable in which not only the outside but also the inside is monitored in order to detect movements or foreign objects in both directions.

It goes without saying that the closing element can be moved not only between a fully open and a fully closed position. Intermediate positions are also conceivable.

At least in exemplary embodiments, additional safety monitoring is provided in the closing level. This can be a light barrier or a light grid. The light barrier/light grid can be designed based on transmitters and receivers for visible light. Alternatively, however, the use of transmitters and receivers for non-visible light (infrared light or the like) is also conceivable. Furthermore, configurations of sensors that use laser beams for monitoring are also conceivable.

The use of a so-called impact bar on the closing edge of the gate is also conceivable. A blow bar enables contact-based monitoring of the closing edge for collisions.

The closing level is generally the opening of the gate or door. It goes without saying that the closing plane does not necessarily have to be completely flat. Accordingly, "curved" closing planes are also conceivable.

The first operating mode and the second operating mode are usually movement modes. In other words, it is provided, at least in essential embodiments, that the closing element reverses as quickly as possible in the first operating mode, that is to say is opened again as quickly as possible. Accordingly, it is not just about stopping the closing element in a specific position. The second operating mode differs from a normal operating mode by a reduced closing speed/drive speed of the closing element.

The drive is preferably operated in the first operating mode and/or in the second operating mode as a function of a current position (in particular of the closing edge) of the closing element. If accordingly upon penetration a foreign object in the second distance range, it is determined that the door is still sufficiently open, the reaction can be fundamentally different than in a situation in which it is determined that the closing element of the door has already been moved more in the direction of the closed position.

A current height or vertical position of the foreign object can be used and taken into account for this evaluation, particularly in the case of a vertically closing door. In the case of a horizontally closing gate (for example with two closing elements that can be moved towards one another), a width of the foreign object can accordingly be taken into account.

In this context, it is provided, at least in exemplary embodiments, that the monitoring device can detect not only the presence of a foreign object but, if possible, also other geometric information (height and/or width, etc.).

In an exemplary embodiment of the protective device, the first distance range is a close range, with the second distance range being a far range. In exemplary embodiments, the close range can also include the closing plane, at least a part of it. At least the area close to the closing plane is adjacent. The far range is further away from the closing plane than the close range.

In a further exemplary embodiment of the protective device, dimensions of the first spacing area and/or the second spacing area are additionally defined as a function of a position of the closing element. As already indicated above, a height and/or width of the foreign object can also be taken into account for this. The control device is set up for this purpose.

In other words, it is conceivable not only to determine a current distance between the foreign object and the closing plane, but also to take into account the current position of the closing element. If the closing element (on a vertically closing gate) is still far enough up, the reaction can be different than in a case in which the closing element has already moved quite far down. The same applies to different opening states for horizontally closing gates. Furthermore, it is conceivable to detect a movement vector of the foreign object. This may also include a determination of a component of the motion vector towards the closing plane of the door. In this way it can be determined whether a collision or even pinching can occur. If there is a certain danger, an adequate response can be made with knowledge of the movement data of the foreign object.

Accordingly, a control algorithm can be optimized to minimize alarm times and false alarms as much as possible. For example, a goal may be to make the first range (close range) as small as possible to minimize the occurrence of alarm conditions/false alarms.

In other words, slower closing of the closing element is more likely to be accepted than an "emergency situation" that leads to reversing. The latter would lead to considerable downtime.

The first mode of operation is a stop and reverse mode. This is primarily used to avoid collisions or as anti-trap protection.

The control device is designed to move the closing element in the second operating mode at a reduced closing speed. In this way, alarms that lead to reversing are avoided. Nevertheless, the reduced closing speed creates options for reacting in the event that the foreign object moves closer to the closing level. However, productivity can be maintained to a high degree.

According to a further exemplary embodiment of the protective device, the control device is designed to determine the closing speed of the closing element to be defined in the second operating mode as a function of a detected speed of a foreign object. The detected speed of the foreign object can be a speed component in the direction of the closing element or in the direction of the closing plane. In other words, the closing speed of the closing element can be selected such that the closing element can still safely reverse when the foreign object comes closer to the closing plane and penetrates into the first distance range (close range). Accordingly, the control device can be designed to at least approximately determine a movement vector of the foreign object on the basis of the sensor data provided by the monitoring device.

It goes without saying that safety factors can be taken into account in order to take into account unforeseen changes in speed and/or changes in direction of the foreign object when determining the closing speed in the second operating mode.

According to a further exemplary embodiment of the protective device, the control device is designed to define the closing speed of the closing element in the second operating mode as a function of a current position of the closing element. So if the "gap" between the closing edge of the closing element and the foreign object is still large enough, under certain circumstances only a slight delay (or no delay at all) in the closing speed of the closing element is sufficient to prevent the foreign object from penetrating into the close range (first Distance range) to be able to react.

In a further exemplary embodiment, the distance ranges are defined in relation to the closing edge of the closing element. If necessary, the movement (closing speed) of the closing element is also taken into account.

The distance areas can be “discs” or “cuboids”, i.e. volumes that are defined in advance of the closing plane. It is However, it is also conceivable to define the distance ranges via vertical planes, each of which represents a boundary between 2 ranges.

It is also conceivable to define the distance ranges based on the situation. It is thus conceivable to define an (individual) close range and an (individual) far range for a detected foreign object depending on its characteristics. This can take place as a function of a detected position, shape and/or a movement vector of the foreign object. Furthermore, the distance ranges can also be made dependent on the current position of the closing edge of the closing element. In other words, the distance ranges are not necessarily static.

Nevertheless, a more or less static definition of the distance ranges is also conceivable. Thus, this may include a fixed distance X from the closure plane for the first range of spacing and a fixed distance Y from the closure plane for the second range of spacing, with the "depth" of the second range of spacing equal to the value of Y-X. Both spacer areas can be aligned essentially parallel to the closing plane.

According to a further exemplary embodiment of the protective device, it also has a position determination unit for the closing element, in particular for the closing edge, with the control device being designed to operate the drive for the closing element as a function of a position signal. This can be a further safety device.

Such a position determination unit can, on the one hand, detect the current position (actual position) of the closing edge. This is a current height for a vertically closing gate. The determined position can be used by the control device in order to operate the drive for the closing element, in particular in the second operating mode, in such a way that false alarms, alarms and associated downtimes of the system are avoided. Furthermore, the determined position can also be used to define the distance ranges. The distance ranges can accordingly (additionally if necessary) depending on the actual position of the closing edge.

According to a further exemplary embodiment of the protective device, the position determination unit includes a light grid that monitors the closing plane that can be closed by the closing element in order to determine the position of the closing element. In this way, an undesired intrusion of foreign objects into the closing plane can also be detected via the position determination unit. The position determination unit and the monitoring device for monitoring the safety zone in front of the closing level can be combined to further increase operational safety.

In alternative configurations, the position determination unit has encoders or similar sensors that enable the position of the closing edge to be determined on the basis of drive information, for example on the basis of a rotation angle of a drive shaft and/or a winding shaft for the closing element. In this way, the position of the closing edge can be determined indirectly, but nevertheless with sufficient accuracy.

According to a further exemplary embodiment of the protective device, the control device is also designed to stop and/or reverse the closing element on the basis of signals provided by the position determination unit if a foreign object is detected in a monitoring area of the position determination unit. In this way, an (additional) anti-trap protection is guaranteed.

According to a further exemplary embodiment of the protective device, a blow bar is arranged on the closing edge of the closing element, which has at least one contact sensor, and the control device is designed to stop or reverse the closing element if contact with a foreign object has been detected via the contact sensor . Such a blow bar requires physical contact with a foreign body in order to receive a signal to reverse of the gate to issue. Nevertheless, the protection against pinching can also be increased in this way.

According to a further exemplary embodiment of the protective device, the control device is designed to control the drive on the basis of data provided by the monitoring device, depending on whether a detected foreign object is in a first distance range, a second distance range, or a third distance range , to operate selectively in a first mode of operation, a second mode of operation, or in a third mode of operation.

In other words, it is conceivable to define not just two distance ranges but three distance ranges. This can consequently include a close range as well as a first far range and a second far range. The first long-distance range precedes the close-up range. The second remote area is in front of the first remote area. The third mode of operation is associated with the second long range (third distance range). The second operating mode is associated with the first long range (second distance range). The first operating mode is assigned to the close range (first distance range).

The control device can now be designed to close the closing element at a speed that is reduced compared to the normal operating mode when a foreign object has been detected in the third distance range. If it is determined that the foreign object penetrates into the second distance range, the control device can further reduce the closing speed of the closing element. If it is now determined that the foreign object also penetrates into the first distance range, the control device can reverse the drive in order to reverse the closing element.

It goes without saying that, according to a further exemplary embodiment, instead of discrete distance ranges with associated operating modes, a type of characteristic map is provided, so that the closing speed depends on the distance from the foreign object (and possibly depending on other values, such as the shape of the foreign object, the current position of the closing edge, etc.) is adjusted continuously or quasi-continuously.

In other words, the number of distance ranges can be further increased in order to bring about a continuous adaptation of the closing speed if necessary.

These configurations are encompassed by key aspects of the present disclosure since the distance ranges can be (small) sections from the "map".

According to a further exemplary configuration of the protective device, the at least one sensor unit of the monitoring device is designed as a laser scanner or image detection sensor, which is designed to monitor an area in front of the closing level, and in an area monitored by the sensor unit, at least the first distance area and the second distance range is defined.

It is conceivable to use a laser scanner that not only monitors a level but an area or even a room. In this way, the sensor unit can be used to monitor a number of distance ranges and, if necessary, also to record information about the shape and/or the movement characteristics of the foreign object.

In addition to the use of laser-based sensors (e.g. laser scanners), the use of imaging sensors for image acquisition is also conceivable. Accordingly, the imaging sensor can be designed as a CCD camera, for example. The apron can be monitored in a similar way on the basis of image data. It is conceivable to combine multiple image capture sensors together to enable stereo capture or 3D capture. The image capture by the at least one image capture sensor can also include a capture of image data outside of the range that is usually visible to the human eye, ie approximately in the infrared range. Infrared cameras can be combined with corresponding infrared emitters. In this way, monitoring based on the acquisition and evaluation of image data can also be guaranteed when the lighting conditions are unfavorable for the human eye or for image acquisition sensors that work in the visible spectral range.

Furthermore, the use of radar sensors or what are known as lidar sensors for monitoring the apron by the sensor unit is also conceivable. In general, sensors of different types can also be combined with one another, such as laser sensors and image acquisition sensors, in order to increase the informative value of the monitoring.

It is conceivable to provide one or more sensors. It is also conceivable to assign a sensor to each distance range. However, it is preferred to provide one or more sensors that monitor the security zone, with the division into distance ranges taking place in software.

Particularly in the case of a vertically closing gate, it is conceivable to arrange the sensor in the area of an upper traverse and/or to the side of it. Accordingly, in such a configuration, the sensor would look from top to bottom. If the sensor were arranged on the side, it would look diagonally downwards from above.

According to a further exemplary configuration of the protective device, the size of the first distance range and/or the second distance range can be changed, with the control device being designed to adapt the distance ranges on a case-by-case basis depending on a status parameter of the locking element and/or a status parameter of the foreign object.

Status parameters of the closing element can relate to the closing speed or the current position (actual position). State parameters of the foreign object can be the current position (distance, horizontal position, vertical position), shape (height, width) and velocity (motion vector and components thereof).

Regarding the use, the object of the invention is achieved by using a protective device according to at least one embodiment described herein as a door or gate for an enclosure of a machine or system, in particular for closing an assembly opening or access opening.

Regarding the method, the object of the invention is achieved by a method for operating a protective device in the form of a protective door or a protective gate for a plant, in particular a production plant, according to claim 14.

By way of example, the monitoring is carried out in relation to a closing edge of a closing element. Accordingly, the drive is operated in the first operating mode and/or in the second operating mode as a function of an actual position of the closing edge and/or an actual speed of the closing element

The method may be performed using a protection device according to at least one of the embodiments shown herein. The opposite the protective device is designed, at least in exemplary embodiments, to be operated on the basis of the method.

Fig. 1

eine perspektivische Ansicht einer beispielhaften Ausführungsform einer Schutzvorrichtung in Form eines Schutztores;

Fig. 2

eine perspektivische Ansicht einer weiteren beispielhaften Ausführungsform einer Schutzvorrichtung in Form eines Schutztores;

Fig. 3

eine schematische, stark vereinfachte Schnittansicht zur Veranschaulichung einer weiteren beispielhaften Ausführungsform einer Schutzvorrichtung in Form eines Schutztores;

Fig. 4

eine schematische, stark vereinfachte Schnittansicht zur Veranschaulichung einer weiteren beispielhaften Ausführungsform einer Schutzvorrichtung in Form eines Schutztores;

Fig. 5

ein schematisches Blockdiagramm zur Veranschaulichung einer beispielhaften Ausführungsform eines Verfahrens zum Betreiben einer Schutzvorrichtung; und

Fig. 6

ein schematisches Blockdiagramm zur Veranschaulichung einer weiteren beispielhaften Ausführungsform eines Verfahrens zum Betreiben einer Schutzvorrichtung.

Further features and advantages of the invention result from the following description and explanation of several exemplary embodiments with reference to the drawings. Show it:

1

a perspective view of an exemplary embodiment of a protective device in the form of a protective gate;

2

a perspective view of a further exemplary embodiment of a protective device in the form of a protective gate;

3

a schematic, highly simplified sectional view to illustrate a further exemplary embodiment of a protective device in the form of a protective gate;

4

a schematic, highly simplified sectional view to illustrate a further exemplary embodiment of a protective device in the form of a protective gate;

figure 5

a schematic block diagram to illustrate an exemplary embodiment of a method for operating a protective device; and

6

a schematic block diagram to illustrate a further exemplary embodiment of a method for operating a protective device.

1 FIG. 12 illustrates a protection device, generally designated 10, by means of a perspective front view of an exemplary embodiment. The protective device 10 is embodied as a machine protective gate or protective gate 12, for example. For example, the protective gate 12 serves to enable controlled access to a facility 14 . When the protective gate 12 is closed, the system 14 is not accessible. This can be desirable from a safety perspective when the system 14 is in operation. However, this is not to be understood as limiting.

The system 14 can be a production system, for example. Other embodiments are conceivable. In general, the protective gate 12 can also be designated and designed as an industrial gate. At least in exemplary embodiments, the protective gate 12 is a so-called high-speed protective gate. In the context of the present disclosure, high-speed safety gates are safety gates with closing speeds greater than 0.5 m/s. Again, this should not be understood as limiting.

The protection device 10 includes a closure plane 18, which can also be referred to as an opening or access opening. in the in 1 In the exemplary embodiment shown, the closing plane 18 is secured by (lateral) posts 20, 22 and by a crossbar 24 (in 1 only shown dashed).

The protective device 10 comprises a closing element 26, which in FIG 1 embodiment shown is designed as a web. Such webs are regularly flexible and can be wound up. The closure member 26 includes a closure edge 28 that defines one end of the closure member 26 .

in the in Figures 1 to 4 In the embodiments shown, the gates/doors are designed as vertical closing/vertical running guards. Accordingly, the closing element 26 closes the closing plane 18 from top to bottom. Accordingly, in the closed state, the closing edge 28 is adjacent to the floor 32 . The closing edge 28 extends in a horizontal direction. In this case, contact between the closing edge 28 and the base 32 can also occur. Basically However, protective devices with horizontally closing closing elements are also conceivable. With such protection devices, the closing edge of the closing element would be oriented vertically and aligned approximately parallel to one of the (side) posts.

A drive 38 is provided for driving the closing element 26 . The drive 38 includes a motor. It is also conceivable to provide a reduction/translation gear. The drive 38 is in the in 1 shown embodiment is coupled to a winding shaft 40 . The drive 38 rotates the winding shaft 40 to selectively wind or unwind the closure member 26. In this way, the protection device 10 can be opened or closed.

In 1 the closing movement of the closing element 26 is indicated by an arrow labeled 44 . A double arrow labeled 46 illustrates an actual opening or an actual position of the closing edge 28/of the closing element 26. The opening 46 released by the closing element 26 changes continuously when the closing element 26 is moved. In this way, the closing element 26 can be moved between a fully closed position and a partially or fully open position.

A control device 50 is provided for controlling the drive 38 and other functions of the protective device 10 . The control device 50 can be a central or a distributed control device. In the present example, the control device 50 also serves to control safety functions and monitoring functions of the protective device 10 .

In 1 a position determination unit 54 is indicated—again by dashed lines. The position determination unit 54 includes, for example, a light grid 56. A dashed arrow labeled 58 illustrates a light beam. The light grid 56 is suitably provided with transmitters and receivers. On the one hand, the light grid 56 can be used to determine a current position of the closing element 26 or its closing edge 28 . Furthermore, the light grid 56 can also be used to detect foreign objects in the closing plane 18 . The However, light grid 56 is not suitable for monitoring an area in front of the protective device 10 . In other words, the light grid 56 cannot be used to detect objects before they have actually entered the closing plane 18 .

In alternative configurations, the position determination unit 54 uses signals that are provided by sensors/rotary encoders and similar elements that are assigned to the drive 38 or the winding shaft 40 for the closing element 26 . The current position of the closing edge 28 can thus be determined indirectly from the number of revolutions or from the angle of rotation of the winding shaft 40 .

Furthermore, a monitoring device 64 is provided, which includes a sensor unit 66 . in the in 1 embodiment shown, the sensor unit 66 has a laser scanner 68 . In 1 a field of view 70 of the laser scanner 68 is indicated by dashed lines merely as an example. Overall, the monitoring device 64 is designed to monitor a front area 72 of the closing plane 18 or the protective device 10 . As already explained above, the sensor unit 66 can alternatively also be designed as a radar sensor, lidar sensor or as an image sensor. Combinations of different sensor types are conceivable.

With reference to 2 1, another exemplary embodiment of a protection device 110 in the form of a protection gate 112 is illustrated. The protection device 10 according to FIG 1 and the protection device 110 according to FIG 2 are basically similar. The following detailed descriptions therefore also apply to the previously illustrated embodiment of the protective device 10 according to FIG 1 , and vice versa.

The guard 110 has a closure plane 118 defined by posts 120, 122 and a cross member 124. The protective device 110 is also provided with a closing element 126 which is formed, for example, from a plurality of segments which can be pivoted relative to one another. Accordingly, the protective device 110 can also be referred to as a segment gate. The design of the closing element 126 as a segmented door leaf and the design of the closing element 26 (cf 1 ) as a web are merely exemplary in nature and should not be construed as limiting.

The closing element 126 has a closing edge 128 . The protective device 110 is designed as a vertically closing protective device. Accordingly, the closing edge 128 is arranged on an underside of the closing element 126 . For example, the closing edge 128 is designed as a so-called impact bar. According to this embodiment, the closing edge 128 is provided with at least one contact sensor 130 . It goes without saying that the protective device 110 can also be provided with a position determination unit for determining a current position of the closing edge 128 of the closing element 126 (compare the design of the position determination unit 54 in 1 ). The position can be determined using light grids, encoders and similar sensors.

Furthermore, in 2 with 138 a drive for the closing element 126 is indicated. The drive 138 acts on the closing element 126 in order to selectively open or close it. In 2 a closing direction is denoted by 144 . Furthermore, a double arrow labeled 146 indicates an actual opening in the closing plane 118 of the protective device 110 .

By designing the closing edge 128 as an impact bar, a safety function is implemented, in particular protection against pinching. If a foreign object is arranged in the opening 146 and is contacted by the closing edge 128 when the protective device 110 is closed, the contact sensors 130 are triggered and the drive 138 can be controlled accordingly in order to quickly reverse the closing element 126.

Also in 2 a controller 150 is provided to control the operation and safety organs of the protection device 110. As already indicated above, it is also conceivable to provide separate control devices for safety-related functions for reasons of redundancy.

The protective device 110 is provided with a monitoring device 164, which corresponds to the monitoring device 64 of the protective device 10. FIG 1 is at least similar in design. The monitoring device 164 is also provided with a sensor unit 166 . The sensor unit 166 is designed as a laser scanner 168 by way of example. Other sensor types are conceivable. A field of view 170 of the sensor unit 166 is in 2 indicated by dashed lines. The field of view 170 of the sensor unit 166 is designed to monitor an area in front of the protective device 110 172 .

A comparison of the configurations according to 1 and 2 shows that in 1 the sensor unit 66 is arranged laterally and looks at the apron 72 from "obliquely above". In 2 the sensor unit 166 is arranged "top center". Both variants are basically conceivable. In this respect, too, the configurations in 1 and 2 not to be understood as limiting. By way of example, the sensor unit 166 is accommodated on the crossbeam 124 . However, it is also conceivable for the sensor unit 166 to be arranged spatially separately/at a distance from it on a wall and/or ceiling in the vicinity of the protective device 110 .

A security zone 176 that can monitor the at least one sensor unit 166 is defined in advance 172 . For example, the safety zone 176 is subdivided into a first distance area 178 and a second distance area 180 . The first distance range 178 can also be referred to as the close range. The second distance range 180 can also be referred to as the far range.

The first spacing region 178 defines a near zone 186. The second spacing region 180 defines a far zone 188. The near zone 186 is adjacent to the closure plane 118. FIG. It is also conceivable to align the sensor unit 166 in such a way that the near zone 186 also includes the closing plane 118 . Far zone 188 is spaced farther from closure plane 118 than near zone 186.

At least in exemplary embodiments, the present disclosure pursues the approach of monitoring both distance areas 178, 180 or both zones 186, 188 in order to be able to determine the presence of foreign objects there. je depending on whether a foreign object has now been detected in the first distance range or the second distance range, the drive 138 can be acted on differently in order to selectively actuate the closing element 118 . In this way, it is possible to react more flexibly overall to imminent collisions and/or the risk of being trapped.

In 2 For purposes of illustration, foreign objects 194, 196, 198 are indicated. In principle, the foreign objects can also be people. Monitoring device 164 with sensor unit 166 is preferably designed to detect not only the presence of foreign objects 194, 196, 198, but also other characteristics, such as the direction of movement, speed and the shape/size of foreign objects 194, 196, 198.

A conceivable movement of the foreign object 194 is indicated by a speed vector 200 . Accordingly, it can be assumed that the foreign object 194 is heading towards the closing plane 118 perpendicularly or almost perpendicularly at a specific speed. If the foreign object 194 now penetrates into the (second) distance range 180 while the closing element 126 is being closed, a pre-alarm can initially be output. As a reaction to this, the closing speed of the closing element 126 can be reduced, for example. In this way it can be ensured that the closing element 126 can be reliably stopped and reversed if the foreign object 194 should also penetrate into the (first) distance region 178, ie into the near zone 186.

The movement of the foreign object 196 is characterized by a speed vector 202 . Accordingly, the foreign object 196 also moves parallel or essentially parallel to the closing plane 118 of the protective device 110 . Additionally is in 2 a current shape (height) of the foreign object 196 is indicated by a double arrow labeled 204 . Such information can also be evaluated by the control device 150 in order to control the drive 138 for the closing element 126 on a case-by-case basis. A main aim of the monitoring is to prevent collisions and/or jamming of the foreign objects 194, 196, 198 with/on the closing element 126. In this respect, the height of the foreign object 196 is of interest, since this a current position of the closing edge 128 of the closing element 126 can be adjusted.

The movement of the foreign object 198 is illustrated by a speed vector 206 . The foreign object 198 is also moving toward the closure plane 118 of the protection device 110, but not perpendicularly or substantially perpendicularly thereto. However, the velocity vector 206 has a component 208 that illustrates a magnitude of velocity perpendicular to the closing plane 118 . These values can also be recorded by the monitoring device 164 and processed accordingly by the control device 150 in order to control the drive 138 in a specific manner when the foreign object 198 enters the second distance range 180 and/or the first distance range 178.

With reference to 3 and 4 further exemplary configurations of protective devices 210, 310 in the form of protective gates 212, 312 are illustrated. 3 and 4 show schematic, highly simplified sections perpendicular to the respective closing plane 218, 318. For the basic structural design of the protective devices 210, 310, reference is made to the figures 1 and 2 illustrated designs of protection devices 10 and 110 referenced.

Both protective devices 210, 310 have closing elements 226, 326 which can be moved in the closing plane 218, 318 between an open and a closed position. Furthermore, a position determination unit is indicated in each case with 254, 354, which comprises, for example, a light grid 256, 356 with transmitters 260, 360 and/or receivers 262, 362. In this way, a current position (corresponding to the respective actual opening 246, 346) of a closing edge 228, 328 of the closing element 226, 326 can be determined and monitored.

In addition, the protective devices 210, 310 each have a monitoring device 264, 364, which is provided with at least one sensor unit 266, 366 each. The respective sensor unit 266, 366 is preferably a laser scanner, which is designed for two-dimensional and/or three-dimensional monitoring of an area in front of 272, 372 of the protective device.

In the embodiment according to 3 a first distance area 278 and a second distance area 280 are defined in the run-up 272 , which together form a safety zone 276 . If a foreign object 296 enters, it can therefore not only be detected whether the foreign object 296 is entering the safety zone 276 (compare the movement vector/velocity vector 302), but also whether the foreign object 296 is entering the first distance range 278 or the second distance range 280. For example, driving the foreign object 296 into the (outer) second distance region 280 can initially result in the closing element 226 being driven further in order to close the protective device 210, but at a reduced closing speed. Then, when the foreign object 296 enters the (inner) first clearance area 278, the closing element 226 can be abruptly stopped and opened (reversed) again.

Furthermore, it is conceivable that a current height 304 of the foreign object 296 is also detected by the monitoring device 264 . The height 304 of the foreign object 296 can be brought in relation to the actual position 246 of the closing edge 228 of the closing element 226 . In this way, the operability of the protection device 210 can be maintained for a long time without sacrificing protection against collisions and/or entrapment.

In the initial example according to 4 a first distance area 378, a second distance area 380 and a third distance area 382 are defined in advance 372, which together form a safety zone 376. If a foreign object 396 enters, it can therefore not only be detected whether the foreign object 396 is entering the safety zone 376 (compare the motion vector/velocity vector 402), but also whether the foreign object 396 is in the first distance range 378, the second distance range 380, or enters the third clearance zone 382.

For example, driving the foreign object 296 into the (outer) third distance region 382 can initially result in the closing element 326 being driven further in order to close the protective device 310, but at a reduced closing speed. If the foreign object 396 penetrates into the (middle in this exemplary embodiment) distance region 380, the closing element 326 can initially be driven at an even further reduced closing speed. Only when the foreign object 396 penetrates into the (inner) first distance region 378 can the closing element 326 be stopped abruptly and opened (reversed) again.

In this way, the operational state of the protection device 310 can be maintained for a long time. False alarms can be avoided. Instead, there are pre-alarms in the second distance range 380 and in the third distance range 382, which are initially used to delay the closing speed of the closing element 326.

Furthermore, it is conceivable that a current height 404 of the foreign object 396 is also detected by the monitoring device 364 . The height 404 of the foreign object 396 can be brought in relation to the actual position 346 of the closing edge 328 of the closing element 326 . In this way, the operability of the protection device 310 can be maintained for a long time without sacrificing protection against collisions and/or entrapment.

With reference to figure 5 an embodiment of a method for operating a protective device is illustrated on the basis of a schematic block diagram. The guard is a guard door or gate. In exemplary configurations, the protective device is a machine protection gate or a machine protection door. Such protective devices are usually provided with motor-driven closing elements.

The method includes a step S10, which relates to the provision of a monitoring device. The monitoring device is an example a laser scanner monitoring facility. The monitoring device or its sensor unit is installed in such a way that an area in front of a closing level of the protective device can be monitored. The closing element can be moved in the closing plane to release or close an opening.

A further step S12 relates to an execution of a closing process of the protective device. For this purpose, it is initially provided that the closing element closes at a specific closing speed. In other words, a drive for the closing element is controlled accordingly. At least in exemplary embodiments, the monitoring device is used primarily to monitor the closing process. When the closing element is closed, there is always a risk of being trapped or a risk of collisions between foreign objects and the closing element.

Step S12 is consequently linked to step S14, which relates to monitoring of the closing process. The monitoring takes place, for example, with a monitoring device that has at least one sensor unit in the form of a laser scanner. Alternatively, the at least one sensor unit can have an imaging sensor (video camera). Other types of sensors for monitoring are conceivable. In this way, an area in front of the monitoring device can be monitored. For this purpose, a safety zone can be defined in advance, which, for example, includes a first distance range (close range) and a second distance range (far range). As already explained above, it is also conceivable to define three or even more areas in the security zone.

The monitoring device is designed to detect the intrusion of foreign objects into the safety zone and to emit corresponding signals. At least in exemplary embodiments, the monitoring device is also designed to record further information relating to the foreign objects. This can affect a position, speed, shape, size, height, etc. of the foreign objects.

The monitoring follows an algorithm that includes a step S16. Step S16 is a decision step. In step S16, it is checked whether or not a foreign object has been detected in the safety zone. If no object was detected, the monitoring can be continued, step S14.

If an object was detected in the safety zone, step S18 follows step S16. Step S18 is also a decision step. In step S18 it is checked whether the detected object in the safety zone is in the first distance range (close range) or in the second distance range (far range).

If it has now been established that the detected object is in the far range (second distance range), then a step S20 follows, in which operating parameters for a corresponding (second) operating mode are defined. In this second operating mode, there is feedback/feedback to step S12, whereupon the drive is controlled in such a way that the closing element is closed at a reduced closing speed.

In this way, an alarm situation is avoided, which could lead to a loss of production, at least for a short time, since the safety device would be put out of operation for a short time. Instead, there is a kind of pre-alarm, with the protective device remaining operational. Due to the reduced closing speed, it is still possible to react if the foreign object penetrates the close range.

If, instead, it is determined during the monitoring that the detected object is in the close range (first distance range) or penetrates into the close range starting from the far range, then there is actually an alarm condition since a collision or jamming is imminent. Step S22 follows, which relates to operating the drive for the closing element in a first operating mode. The drive is controlled in such a way that the closing element is abruptly stopped and reversed. This takes place in a step S24 which follows step S22.

It goes without saying that, in addition to the first operating mode and the second operating mode, there is also a normal operating mode or a normal closing operating mode. The normal operating mode is the operating mode of the drive for the closing element when no object has been detected in the safety zone.

The method can be implemented using a protection device according to any of the embodiments described herein.

With reference to 6 an exemplary embodiment of an algorithm that can be used in a method for operating a protection device is illustrated on the basis of a schematic block diagram.

The method includes an initial step S50, which indicates a start. A step S52 follows, in which a mode, in particular an operating mode for driving a closing element of a protective device, is selected. At least in exemplary embodiments, a closing speed for the closing element is selected together with the selection of the mode. The algorithm usually starts with a normal operating mode, associated with a (high) normal closing speed for the closing element.

The closing element is closed on the basis of the selected operating mode, with a position monitoring taking place in a step S54. This can relate in particular to monitoring a position of a closing edge of the closing element. For this purpose, a position determination unit is provided, for example in the form of a light grid, which is assigned to a closing plane of the protective device.

A parallel step S56 relates to the monitoring of an area in front of the protective device. As already explained above, there is at least a first distance range and a second distance range (close range and far range) in advance. The surveillance aims to detect the presence or intrusion of To detect foreign objects in a safety zone, which is defined by the first distance range and the second distance range.

In other words, monitoring takes place both in step S54 and in step S56. The monitoring in step S54 can also be used to detect the presence or intrusion of foreign objects into the closing level, for example if a light grid is used for monitoring.

If the monitoring step S56 does not report an intruding foreign object, the closing element is closed until an end stop is detected in a step S58. In this way it can be detected that the protective device is fully closed. A step S60 follows, which represents an end of the closing process or of the algorithm.

Step S56 is directly or indirectly followed by step S64, which can also be referred to as a decision step. In exemplary embodiments—illustrated by dashed lines—steps S56 and S64 are interposed by an optional intermediate step S62. Step S62 relates to a definition of areas/parameters as a function of a position of the closing element or of its closing edge detected in step S54. In this way, threshold values, parameter ranges and the like can be defined. It is also conceivable to adapt the cut or the definition of the close range and the far range to a detected actual position. In other words, it cannot be ruled out in principle that the areas in the safety zone are variable.

On the basis of a parameter set adapted in this way or on the basis of a fixed parameter set, it is checked in a further step S64 whether or not a foreign object was detected in the safety zone. If no object was detected, the closing process and the monitoring of the apron (step S56) can be continued.

However, if the presence/intrusion of a foreign object was detected in step S64, a subsequent step S66 queries whether the foreign object was detected in a first distance range or a second distance range. If the object was detected in a second distance range (far range), there is a corresponding feedback and adjustment of the operating mode in step S52. This includes in particular an adjustment (reduction) of the closing speed. This is done as a precautionary measure to reduce the risk of collision while still maintaining the operability of the protection device.

However, if it was determined in step S66 that the foreign object is in the first distance range (close range), then in a subsequent step S68 the closing element is stopped abruptly and operated in the opposite direction (reversed). In this way, collisions and/or jamming should be avoided. In such a case, an alarm signal can also be generated and output. Step S70 follows, in which the method is ended. As a rule, it is then necessary to investigate the cause and/or to remove foreign objects.

Claims (14)

1. A protective device (10, 110, 210, 310) in the form of a protective door or protective gate (12) for a plant (14), in particular a production plant, the protective device (10, 110, 210, 310) comprising:

   - a closing element (26, 126, 226, 326), in particular a high-speed closing element (26, 126, 226, 326), having a closing edge (28, 128, 228, 328), wherein the closing element (26, 126, 226, 326) is movable in a closure plane (18, 118, 218, 318) between an open position and a closed position,

   - a drive (38, 138) for driving the closing element (26, 126, 226, 326),

   - a monitoring device (64, 164, 264, 364) with at least one sensor unit (66, 166, 266, 366), which monitors an forefield (72, 172, 272, 372) of the closure plane (18, 118, 218, 318), in order to detect the intrusion of foreign objects (194, 196, 198, 296, 396) into a safety zone (176, 276, 376) in the forefield (72, 172, 272, 372) of the closure plane (18, 118, 218, 318), and

   - a control device (50, 150) that is configured to selectively operate the drive (38, 138) in a first operating mode or in a second operating mode based on data that is provided by the monitoring device, depending on whether a detected foreign object (194, 196, 198, 296, 396) is located within the safety zone (176, 276, 376) in a first distance range (178, 278, 378) or a second distance range (180, 280, 380),

   wherein the first operating mode is associated with the first distance range (178, 278, 378) and the second operating mode is associated with the second distance range (180, 280, 380),

   wherein the first operating mode is a stop and reverse mode,

   wherein the second operating mode is a reduced speed mode, and

   wherein the second distance range (178, 278, 378) is in front of the first distance range (180, 280, 380),

   characterized in that the control device is adapted to define dimensions of the first distance range (178, 278, 378) and the second distance range (180, 280, 380) depending on the current closing speed of the closing element (26, 126, 226, 326).
2. The protective device (10, 110, 210, 310) according to claim 1, characterized in that the first distance range (178, 278, 378) is a close range, and that the second distance range (180, 280, 380) is a far range.
3. The protective device (10, 110, 210, 310) according to claim 1 or 2, characterized in that the control device is adapted to define dimensions of the first distance range (178, 278, 378) and the second distance range (180, 280, 380) additionally depending on a position of the closing element (26, 126, 226, 326).
4. The protective device (10, 110, 210, 310) according to any one of claims 1 to 3, characterized in that the control device (50, 150) is configured to move the closing element (26, 126, 226, 326) in the second operating mode at a reduced closing speed.
5. The protective device (10, 110, 210, 310) according to any one of claims 1 to 4, characterized in that the control device (50, 150) is adapted to define the closing speed of the closing element (26, 126, 226, 326) in the second operating mode depending on a detected speed of a foreign object (194, 196, 198, 296, 396).
6. The protective device (10, 110, 210, 310) according to any one of claims 1 to 5, characterized in that the control device (50, 150) is adapted to define the closing speed of the closing element (26, 126, 226, 326) in the second operating mode depending on a current position of the closing element (26, 126, 226, 326).
7. The protective device (10, 110, 210, 310) according to any one of claims 1 to 6, further comprising a position detection unit (54, 254, 354) for the closing element (26, 126, 226, 326), in particular for the closing edge (28, 128, 228, 328), wherein the control device (50, 150) is configured to operate the drive (38, 138) for the closing element (26, 126, 226, 326) depending on a position signal.
8. The protective device (10, 110, 210, 310) according to claim 7, characterized in that the position detection unit (54, 254, 354) comprises a light grid (56, 256, 356), which monitors the closure plane (18, 118, 218, 318) that is closable by the closing element (26, 126, 226, 326) to determine the position of the closing element (26, 126, 226, 326).
9. The protective device (10, 110, 210, 310) according to claim 7 or 8, characterized in that the control device (50, 150) is further adapted to stop and/or reverse the closing element (26, 126, 226, 326) based on signals that are provided by the position detection unit (54, 254, 354) when a foreign object (194, 196, 198, 296, 396) is detected in a monitoring area of the position detection unit (54, 254, 354).
10. The protective device (10, 110, 210, 310) according to any one of claims 1 to 9, characterized in that the control device (50, 150) is configured to selectively operate the drive (38, 138) in a first operating mode, a second operating mode, or in a third operating mode on the basis of data that is provided by the monitoring device (64, 164, 264, 364), depending on whether a detected foreign object (194, 196, 198, 296, 396) is located in a first distance range (178, 278, 378), a second distance range (180, 280, 380), or a third distance range (382).
11. The protective device (10, 110, 210, 310) according to any one of claims 1 to 10, characterized in that the at least one sensor unit (66, 166, 266, 366) of the monitoring device (64, 164, 264, 364) is arranged as a laser scanner (68, 168) or image acquisition sensor, which is configured to monitor the forefield (72,172, 272, 372) of the closure plane (18, 118, 218, 318), and in that, in an area monitored by the sensor unit (66, 166, 266, 366), at least the first distance range (178, 278, 378) and the second distance range (180, 280, 380) are defined by the control device (50, 150).
12. The protective device (10, 110, 210, 310) according to any one of claims 1 to 11, characterized in that a size of the first distance range (178, 278, 378) and/or of the second distance range (180, 280, 380) is variable, and in that the control device (50, 150) is adapted to adjust the distance ranges on a case-by-case basis depending on a state parameter of the closing element (26, 126, 226, 326) and/or a state parameter of the foreign object (194, 196, 198, 296, 396).
13. A use of a protective device (10, 110, 210, 310) according to any one of claims 1 to 12 as a door or gate (12) for an enclosure of a machine or plant (14), in particular for closing a loading opening or access opening.
14. A method of operating a protective device (10, 110, 210, 310) according to any one of claims 1 to 12, the method comprising the steps of:

    - monitoring the forefield (72,172, 272, 372) of the closure plane with the sensor unit (66, 166, 266, 366) to detect the intrusion of foreign objects (194, 196, 198, 296, 396) into the safety zone (176, 276, 376) in the forefield (72,172, 272, 372) of the closure plane (18, 118, 218, 318),

    - acquiring and processing data that is provided by the monitoring device (64, 164, 264, 364) with the control device,

    - operating the drive (38, 138) for the closing element (26, 126, 226, 326) in the first mode of operation when a detected foreign object (194, 196, 198, 296, 396) is within the safety zone (176, 276, 376) in the first distance range (178, 278, 378), wherein the first mode of operation is a stop and reverse mode, and

    - operating the drive (38, 138) for the closing element (26, 126, 226, 326) in the second mode of operation when the detected foreign object (194, 196, 198, 296, 396) is within the safety zone (176, 276, 376) in the second distance range (180, 280, 380), wherein the second mode of operation is a reduced speed mode,

    characterized by:

    - defining dimensions of the first distance range (178, 278, 378) and/or the second distance range (180, 280, 380) depending on the current closing speed of the closing element (26, 126, 226, 326) with the control device.

Images