Method for operating a gate, detection grid and gate arrangement

Abstract

Method for operating a door (4) with a door leaf (5) movable between a closed position and an open position along a travel path, with a door drive (7) coupled to the door leaf (5), with a door control (8) controlling the door drive (7), and with at least one detection grid (10) having a plurality of detection devices (11) arranged at a distance along the travel path and connected to the door control (8) via a signal path (9), wherein the detection devices (11) assume an activated state upon detecting an object in a detection area assigned to them, wherein the detection grid (10) transmits a pulsed first signal to the door control (8) via the signal path (9) in a nominal operating state (A), when none of the detection devices (11) is activated,wherein the detection grid (10) transmits a non-pulsed second signal to the gate control (8) via the signal path (9) in a fault state (B), characterized in that the detection grid (10) transmits the pulsed first signal at a constant first frequency (f1) in the nominal operating state (A) and that the detection grid (10) transmits a pulsed third signal with a second frequency (f2) deviating from the first frequency (f1) via the signal path (9) to the gate control (8) in a third operating state (C) deviating from the nominal operating state (A) and the fault state (B).

Description

[0001] The invention relates to a method for operating a door with a door leaf movable between a closed position and an open position along a travel path, with a door drive coupled to the door leaf, with a door control that controls the door drive, and with at least one detection grid having a plurality of detection devices arranged at a distance along the travel path and connected to the door control via a signal path. The detection devices each have a detection area assigned to them and assume an activated state upon detecting an object in the detection area. In a nominal operating state, when none of the detection devices is activated, the detection grid transmits a pulsed signal to the door control via the signal path. In a fault state, the detection grid transmits a non-pulsed second signal to the door control via the signal path.

[0002] A gate is used to close a building opening, also known as a door opening. The gate is arranged such that the gate leaf closes the door opening in the closed position and at least partially opens the door opening in the open position. To prevent collisions - particularly during a closing movement, i.e. when the gate leaf moves from the open position towards the closed position - gates usually have safety devices. These are used to detect objects along the travel path. The invention is based on a scenario in which a so-called detection system with a plurality of independent detection units is arranged along the travel path as the safety device.

[0003] However, this presents the difficulty that, for reliable detection, the individual detection devices must be positioned as close as possible along the travel path—especially within the area swept by the door during closing or opening. However, there, they can sometimes be triggered by the door itself.

[0004] The invention is based on a simple signaling method in which either a pulsed OK signal or a non-pulsed error signal is transmitted to the door control system via the particularly unidirectional signal path. The signal path can, without limitation of the invention, be, for example, an electrical conductor, an optical fiber, or a radio channel. A pulsed signal periodically alternates between a low and a high level (of electrical voltage, brightness or radio field strength, etc.). The low level can, in particular, be a 0 state with no signal.

[0005] The convention of a non-pulsed signal as an error signal has the particular advantage that even a complete signal interruption or superposition with a constant interference signal is reliably registered as an error, so that the door can be transferred to a safe operating state.

[0006] Compared to simple detection devices – e.g., light barriers – more complex detection grids pose additional difficulties if they are also activated when the door is moving. Several detection devices are arranged along the travel path, with the travel path running through the various detection zones. As a result, the door leaf activates at least individual detection devices one after the other during a closing movement from the open position to the closed position. If this were to trigger an error signal during each closing movement, the intended operation of the door would be impossible. Completely disabling the detection grid or ignoring the error signal is also undesirable.

[0007] Therefore, gates with detection grids are often equipped with a so-called blanking function. Activation of the detection devices does not trigger an error signal if it occurs consecutively in the closing direction, i.e., particularly from top to bottom. In principle, the activation of any of the detection devices in the detection grid triggers the error condition, as an object in the path of travel, and thus a potential collision hazard, has been detected.

[0008] During blanking, this does not apply to the first or topmost detection device in the closing direction. If this is activated without another detection device being activated beforehand, the detection grid switches to blanking mode. In this mode, the activation of the next non-activated direction device in the closing direction does not result in an error signal, but rather in the continuation of blanking mode.

[0009] In practice, however, it has been shown that this system is also prone to errors – particularly with detection devices that do not extend across the entire height of the door opening. For example, objects other than the door leaf that pass over the detection grid in the closing direction can activate the blanking mode, causing an erroneous OK signal to be transmitted to the door control system. It has already happened that a work platform with a tilted arm entered a door opening in such a way that the arm activated the detection device of the detection grid one after the other from top to bottom. As a result, the detection grid erroneously activated the blanking mode and sent an OK signal to the door control system, despite the work equipment being located in the danger zone along the closing path. As a result, a closing movement of the door leaf was possible, resulting in a collision.

[0010] To eliminate this hazard scenario, improved communication between the detection grid and the gate control system is required. To this end, it has already been proposed to connect the detection grid and the gate control system with a complex network or communication protocol, e.g., a serial or parallel communication protocol. However, this requires additional communication paths, particularly cables and / or additional devices on both the detection grid and the gate control system. The changes made must be compatible and implemented simultaneously.

[0011] Against this background, the invention is based on the object of improving the operational reliability of a generic door using simple means without implementing an additional signaling path. The subject matter of the invention and the solution to this object are a method according to claim 1, a door control according to claim 9, a detection grid according to claim 10, and a door arrangement according to claim 11. Preferred embodiments are specified in the dependent subclaims.

[0012] Based on the generic method, the invention provides that the detection grid transmits the pulsed signal at a constant first frequency (first signal) in the nominal operating state, and that the detection grid transmits a pulsed third signal to the gate control at a second frequency deviating from the first frequency in a third operating state that differs from the nominal operating state and the fault state. As a result, the detection grid is capable of providing differentiated feedback to the gate control that differs from a mere binary signal (either nominal state or fault state). For this purpose, no additional signal path, i.e., in particular, no additional line or radio channel, is required to transmit the additional information.

[0013] The inventive approach provides backward compatibility in two respects. Even if the gate controller does not distinguish between the first and second frequencies, it will still detect a pulsed signal as the absence of a spring state. Likewise, it is sufficient if the detection grid can only emit a pulsed nominal signal or a non-pulsed error signal, since a gate controller capable of further discrimination can thus at least discriminate between the nominal state and the error state.

[0014] Within the scope of the invention, a pulsed signal is to be understood as a signal (in particular electrical voltage, pressure, light intensity, field strength, frequency and / or phase position) that periodically changes between a first state and a second state. The pulsed signal is generated in particular electrically or electronically and can, without limitation of the invention, have a rectangular, triangular, sawtooth, sine or other periodic form. A particularly simple signal processing results from a so-called rectangular signal, which can be generated using the simplest electronic means.

[0015] In principle, it is possible for the first frequency and / or the second frequency to be preprogrammed in the gate control hardware and / or software in the detection grid and / or the gate control. This allows for a particularly simple connection of the two components without any additional setup effort.

[0016] Alternatively or additionally, the first frequency can be determined automatically by the door control system – particularly during an initial setup phase and / or during ongoing operation. This simplifies the setup and operation of the door, as the door control system can be adapted to different makes of light curtains and / or to age-related changes in the first and / or second frequency.

[0017] Particularly preferred is for the gate controller to determine a frequency spectrum of the signals received via the signal path and use this to determine the first frequency. In particular, the frequency spectrum is determined numerically, in particular using a so-called FFT (fast Fourier transformation).

[0018] The first frequency is preferably determined by the largest maximum of the frequency spectrum, especially within a designated frequency range. It is assumed that a nominal signal is present during the initial setup phase and also on average during normal operation.

[0019] Regardless of the method of determining the first frequency, it is preferably in a range between 500 and 2,000 Hz, in particular between 750 and 1,500 Hz, particularly preferably between approximately 800 and 1,000 Hz. In this range, electrical signals in particular do not lead to any significant electromagnetic radiation along the conductors.

[0020] At the same time, the signal is high-frequency enough to ensure reliable detection even in short time spans. Furthermore, the signal can be converted into acoustic signals for diagnostic purposes via a converter, which are in a clearly audible and distinguishable frequency range.

[0021] Preferably, the first frequency and the second frequency are in a predetermined ratio to each other. This allows the second frequency to be directly implemented or determined in the predetermined ratio, both in the case of dynamic detection of the first frequency and in the case of a preprogrammed frequency distribution.

[0022] The second frequency is preferably lower than the first frequency. This allows the second frequency to be detected, for example, by a drop in the signal's frequency. Furthermore, during electrical transmission, electromagnetic radiation is no greater than when transmitting the nominal operating signal. It also ensures that electrical circuits capable of detecting the first frequency are also capable of simultaneously detecting the lower-frequency second signal. This also facilitates automated detection of the first frequency, as this represents the frequency maximum at the highest frequency.

[0023] According to a preferred embodiment of the invention, the third operating state is activated blanking. In this state, one or more detection devices have been activated consecutively in the closing direction. This corresponds to the activation pattern of a closing door, which sequentially passes through the detection areas of the detection devices in the closing direction. During a closing movement, such a pattern does not necessarily indicate a fault, but can, in particular, be part of the normal operating procedure.

[0024] The signal with the second frequency, which indicates the blanking state, enables the door control system—which stores whether the door drive is activated in the closing direction or not—to distinguish whether normal operation is occurring or whether the blanking has been activated incorrectly. In this case, the presence of the third operating state when the door drive is at a standstill is interpreted as an error condition, so that (further) closing is prevented by the door control system.

[0025] During a closing movement from the open position to the closed position, the door control preferably interprets a non-pulsed signal from the detection grid and, if applicable, a signal with a frequency deviating from the first frequency as an error signal and consequently stops the door drive and / or reverses it. Reversing refers to the movement of the door back against the closing direction—in particular, by a small distance between 10 cm and 0.5 m.

[0026] Preferably, the third signal is not interpreted as an error signal, so that the closing movement continues. On the one hand, the third signal cannot generally be interpreted as an error signal. Particularly preferably, the third signal is time-controlled and / or dependent on the closing position of the door leaf and is not interpreted as an error signal. Based on a time control - measurement of the time since the start of the closing movement (indirect position determination) or on the basis of a direct measurement of the closing position of the door leaf (by a travel sensor, a rotary angle sensor on the door drive, etc.), it can be predetermined whether the door leaf is to be expected to enter the detection range of at least one detection device and thus the activation of the blanking. This makes it particularly advantageous to also detect false blanking detections during a closing movement that has already begun.

[0027] Preferably, the third operating state is interpreted as an error signal outside of a closing movement, especially when the door drive is at a standstill. If an error signal occurs (a non-pulsed signal and, if applicable, one or more signals that deviate from a pulsed signal with the first frequency), a closing movement is prevented. In this state, the door drive cannot be controlled by an operator to move the door leaf toward the closed position.

[0028] According to a preferred embodiment, at least one detection device, preferably all detection devices, comprises a light barrier. With a light barrier, a visible or invisible light beam is guided through the detection zone from a transmitter to a receiver. The transmitter and receiver can be arranged opposite one another on either side of the detection zone or next to one another, with at least one reflector formed at the opposite end of the detection zone. The penetration of an object into the detection zone is detected by reducing or completely interrupting the amount of light detected by the receiver. The transmitter can be a focused light source, in particular a laser.To avoid false signals caused by stray light, it is common practice to use a wavelength that does not occur naturally and / or, if necessary, to modulate the light emitted by the light source.

[0029] Particularly preferably, several light barriers are connected to form a so-called light grid in the detection grid. The light grid forms several detection zones, preferably arranged equidistantly along the travel path.

[0030] Within the scope of the invention, it is also possible for further signals with frequencies deviating from the first and second frequencies to be transmitted from the detection grid via the signal path to the gate control.

[0031] Preferably, the nominal operating state is not assigned a single frequency, but rather an OK signal within a frequency range—e.g., 800 Hz to 1,000 Hz. The frequency within this frequency range can transmit additional information—e.g., the alignment from a first value of "poor" at 800 Hz to a second value of "very good" at 1,000 Hz.

[0032] The invention also relates to a gate control system configured to implement the method according to the invention. The gate control system comprises a signal receiver and is configured to process a first signal pulsed at a first frequency received by the signal receiver as a nominal signal, to process a non-pulsed second signal as an error signal, and to process a third signal pulsed at a second frequency as a third operating state. The gate control system is further configured to control the gate drive of a gate and to lock, stop, and / or reverse it depending on the operating state.

[0033] The invention also relates to a detection grid with a plurality of detection devices that can be arranged along a travel path of a gate, and with at least one signal generator that is configured to output a pulsed signal at a first frequency in a nominal operating state, to output a non-pulsed second signal in the event of a fault, and to output a pulsed signal at a second frequency in a third operating state that differs from the nominal operating state and the fault state. The detection grid is configured to be used in a method according to the invention described above. However, due to its inherent technical backward compatibility, it can also be used in conventional gates.

[0034] Furthermore, the invention relates to a gate assembly comprising a building wall having a gate opening, a gate arranged at the gate opening, a gate movable along a travel path between a closed position closing the gate opening and an open position at least partially uncovering the gate opening, and a gate drive coupled to the gate leaf. According to the invention, the gate assembly is provided with a gate control system according to the invention and a detection grid according to the invention, and is configured to carry out the method according to the invention.

[0035] The invention is explained with reference to two figures. They show schematically: Figure 1 shows a schematic representation of a gate arrangement according to the invention and Figure 2 shows a schematic state diagram to illustrate the method according to the invention.

[0036] The Figure 1shows a door assembly 1 according to the invention with a building wall 3 having a door opening 2 and a door 4 arranged at the door opening 2. The door has a door leaf 5 that can be moved between a closed position closing the door opening 2 and an open position at least partially exposing the door opening 2. In the exemplary embodiment, the door leaf 5 is designed as a sectional door. However, the invention is also readily applicable to other types of doors, in particular roller doors, up-and-over doors, or sliding doors.

[0037] The door leaf 5, which is formed from a plurality of panels connected to one another in an articulated manner, is movable between the open position and the closed position along a travel path which, in the exemplary embodiment, is defined by lateral guide rails 6.

[0038] The door leaf 5 is coupled to a door drive 7, which can be used to open or close the door. The door drive 7 is controlled by a door control 8. Furthermore, the door control 8 is connected via a signal path 9 to a detection grid 10, which has a plurality of detection devices 11 arranged along the travel path.

[0039] In the exemplary embodiment, the detection grid 10 is designed as a light grid, whose detection devices 11 form light barriers whose light beams 12 span the lower area of the door opening 2. The detection devices 11 can detect objects located within the travel path in the door opening 2 and process them accordingly by the door control system 8.

[0040] The method according to the invention is based on the Figure 2explained. In addition to the detection devices 11, the detection grid 10 has at least one signal processing unit 10a connected to the detection devices 11, which can switch between a nominal operating state A, an error state B, and a third operating state C. The nominal operating state A is reached in particular when none of the detection devices 11 is activated. The error state B is assumed when an object is detected by the detection devices 11 outside the third operating state C (blanking mode).

[0041] The detection grid 10 also comprises a signal generator 10b which is controlled in the first operating state A with a first frequency f 1 of 800 Hz, in the error state B with a non-pulsed frequency f 0 of 0 Hz and in the third operating state C with a second frequency f 2 of 400 Hz. This transmits the signal via the unidirectional signal path 9, i.e. signal active in one direction, to an associated signal receiver 8a of the door control 8. The signal receiver can detect the presence of a first frequency f 1 , a non-pulsed signal f 0 or a second frequency f 2 in the signal received via the signal path 9. A non-pulsed signal is interpreted as an error signal X and the door drive 7 is blocked against (further) closing movement or is stopped during an ongoing closing movement and reversed if necessary.

[0042] When the first frequency f 1 is detected, a nominal operating state N is assumed in which the gate can be opened (further) outside the opening position or closed (further) outside the closing position.

[0043] When a signal with a second frequency f 2 is detected, the exemplary embodiment also checks whether a closing movement—a closing movement toward the closed position—is currently being performed. In this case, this represents normal operation, and the nominal state N is assumed. If no closing movement is performed, this constitutes an incorrect activation of blanking mode C, resulting in the activation of error state X.

Claims

1. A method for operating a door (4) with a door leaf (5) movable between a closed position and an open position along a travel path, with a door drive (7) coupled to the door leaf (5), with a door control (8) controlling the door drive (7), and with at least one detection grid (10) having a plurality of detection devices (11) arranged at a distance along the travel path and connected to the door control (8) via a signal path (9), wherein the detection devices (11) assume an activated state upon detecting an object in a detection area (12) assigned to them, wherein the detection grid (10) transmits a pulsed first signal to the door control (8) via the signal path (9) in a nominal operating state (A), when none of the detection devices (11) is activated,wherein the detection grid (10) transmits a non-pulsed second signal to the gate control (8) via the signal path (9) in an error state (B), , characterized in that the detection grid (10) transmits the pulsed first signal at a constant first frequency (f1) in the nominal operating state (A) and that the detection grid (10) transmits a pulsed third signal at a second frequency (f2) deviating from the first frequency (f1) to the gate control (8) via the signal path (9) in a third operating state (C) deviating from the nominal operating state (A) and the fault state (B).

2. Method according to claim 1, characterized in that the third operating state (C) is an activated blanking of the detection grid (10).

3. Method according to claim 1 or 2, characterized in that the door control (8) locks, stops and / or reverses the door drive (7) in the event of an error signal.

4. Method according to claim 3, characterized in thatthe second signal from the door control (8), in particular during a closing movement directed from the opening position to the closing position, is interpreted as an error signal (X).

5. Method according to claim 3 or 4 characterized in that the third signal, in particular time-controlled and / or dependent on the closing position of the door leaf (5), is not interpreted as an error signal (X).

6. Method according to one of claims 3 to 5, characterized in that the third signal, especially when the door drive is not active or outside of a closing movement, is interpreted as an error signal (X).

7. Method according to one of claims 1 to 6, characterized in that at least one detection device (11) is a light barrier.

8. Method according to claim 7, characterized in that the detection grid (10) is a light grid.

9. Gate control (8) for carrying out a method according to one of claims 1 to 8 with a signal receiver (8a), wherein the gate control (8) is set up to process a first signal pulsed at a first frequency (f1) received by the signal receiver (8a) as a nominal signal (N), to process a non-pulsed second signal as an error signal (X) and to process a third signal pulsed at a second frequency (f2) as a third operating state (C), and wherein the gate control (8) is further set up to control a gate drive (7) of a gate (4) and to block, stop and / or reverse it depending on the operating state.

10. Detection grid (10) with a plurality of detection devices (11) which can be arranged along a travel path of a gate (4), and with at least one signal generator which is designed to output a pulsed first signal with a first frequency (f1) in a nominal operating state (A), to output a non-pulsed second signal in a fault state and to output a pulsed third signal with a second frequency (f2) in a third operating state (C) which deviates from the nominal operating state (A) and the fault state.

11. Gate arrangement (1) with a building wall (3) having a gate opening (2), with a gate (4) arranged at the gate opening (2), which has a gate leaf (5) movable along a travel path between a closed position closing the gate opening (2) and an open position at least partially releasing the gate opening (2), and a gate drive (7) coupled to the gate leaf (5), characterized in that the gate arrangement (1) is provided with a gate control (8) according to claim 9 and a detection grid (10) according to claim 10 connected to the gate control (8) via a signal path (9) and is configured to carry out a method according to one of claims 1 to 8.

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