Elevator system and monitoring system

The invention relates to an elevator installation with a movable in an elevator shaft of a drive unit elevator car. The elevator system is controlled by a control unit. In addition, sensors are provided for monitoring the state of the elevator system, which are each connected via an assigned bus node to a data bus and connected to the control unit. In addition, the invention relates to a monitoring system for an elevator system comprising a plurality of bus nodes. The bus nodes are connected via a data bus to a control unit, wherein the bus node, a sensor is assigned. The sensor is connected to the associated bus nodes is provided for monitoring the state of the elevator installation.

In elevators safety contacts are used to detect the state of the elevator installation. Conventional elevator systems using safety contacts which are connected in a series circuit with each other, in a functional condition of the elevator installation all safety contacts are closed, so that a positive signal state of the elevator system can be evaluated in a control unit. The disadvantage of such a connection of the safety contacts that no diagnosis is possible if one or more safety contacts are faulty. Consequently, appropriate measures of control unit for controlling the elevator system can be made. Furthermore, with such an interconnection of the safety contacts no identification of safety contacts possible, in which case additional information about intermediate states or counters, etc. can not be transferred.

Such interconnected safety contacts are nowadays often replaced by bus systems to which the safety contacts are connected. These bus systems must comply with the specific safety requirements for lifts.

In WO 03/020627 A1, an elevator system will be described, are arranged in the sensing means which provide fault information on the fault type and position of the fault is available in case of a fault in the area of ​​the shaft doors or car doors a control. The controller can thus trigger a situational safe response taking into account the type of fault, the position of the fault and state information. The detection means which comprise, for example, power switch, switch, Hall sensors, etc., are connected via a bus system with a control unit of the elevator installation. To adjust this bus system with the safety requirements, for example, distributed sensors are used in each case two or more sensors of checks or mutual support are provided. It is further provided that the detection means are set in case of failure in a safe state so as not to affect the elevator system negatively. The detection means are connected via bus node to the bus system, the bus nodes are enhanced by built-in redundant configuration in their security and thus increase the safety of the entire system.

The disadvantage of such a configuration of the bus system that a bus node can also transmit an erroneous message to the control, although this bus node associated sensor signals an error-free or functional state of the elevator system and actually there is no fault condition.

The invention has for its object to eliminate above-mentioned problems and to provide an elevator system and a monitoring system for an elevator system with improved reliability and improved availability.

This object is achieved in a generic elevator system in accordance with claim 1 according to the invention that a bus node associated sensor controls a power supply of the bus node.

The invention is based on the idea that a bus node, which is not supplied with a voltage, can not transmit any defective status message to the control unit, so that in a state check message is no condition. Thus can the transmission of error-free states, although there is an error, prevent. For this purpose the invention provides that the sensor in response to the detected state of the elevator system controls the power supply of the bus node.

Advantageous embodiments of the elevator system according to the invention are the objects of claims 2 to 10th

In an advantageous embodiment of the invention, the power supply of the associated bus node is in a state of the sensor, which characterizes a faulty state of the elevator system, off. This makes it possible that the state of this sensor will only be transmitted to the control unit when a fault-free functional or state of the elevator system is present. Should a faulty condition of the elevator installation are present, the sensor remains in the failed state and the power supply of the associated bus node remains off.

In an advantageous embodiment of the invention the bus node is passively trained, so that the state of the bus node of the control unit is available. Result, the expense for the realization of the bus node remains low.

In an alternative embodiment of the invention the bus node is actively formed. In this case the bus node of the control unit transmits the state of the associated sensor. Such active bus nodes are configured in more complex, but the control unit can be constructed with such an active decentralized bus node and the complexity of the control unit can be reduced.

In an advantageous embodiment of the invention it is provided that the control unit classifies in a lack of a status message of a bus node within a predetermined period of time these bus node with the associated sensor as defective. A bus node is thus classified as faulty if after a while there is no feedback in a passive bus node or received any status message to the control unit with an active bus nodes of the bus node. The control unit is thus capable of recognizing whether the sensor is in a fault-free or in a faulty state.

It is advantageously provided that the control unit in response to the reported or transmitted states of the bus node initiates appropriate measures for controlling the elevator installation. Through the diagnosis, wherein the sensor is an error, an appropriate action can be taken to improve the availability and the reliability of the elevator system specifically.

In a further advantageous embodiment of the invention it is provided that the bus node identification to the control unit to transmit during the transmission of the condition. Thereby, it is avoided that a bus node for another bus node transmits a status message, which may be incorrect.

In an advantageous embodiment of the invention, the sensor comprises a contact which controls the voltage supply of the assigned bus node. It can be formed by a circuit closer or by a switch contact. Depending on requirements, in so far be regarded as defective or as a functioning state, an open or closed contact of the sensor.

In a further advantageous embodiment of the invention, the sensors are formed without contact. Such sensors detect magnetic fields by, for example, a particular condition, so that the voltage supply of the assigned bus node, depending on a particular state of the non-contact sensor can be controlled.

The above object is further achieved in accordance with claim 11 by a monitoring system for an elevator system, in which a sensor controls the voltage supply of the associated bus node.

Advantageous embodiments of such a monitoring system from the subject matter of claims 12 to 17th

The invention of an exemplary embodiment is explained in detail, which is shown schematically in the drawings. In which:

Figure 1 is an elevator system according to the present invention,

2 shows a monitoring system according to the present invention, and

Figure 3 is a designed as a switch sensor.

In Figure 1, an elevator system 10 with an elevator car 12 which is moved in an elevator shaft 15, shown. The elevator car 12 is moved by a drive unit 14 in the elevator shaft 15 between floors A, B, and C of a building. The elevator car 12 has car doors 13 and a cab control 19th In each floor A, B, C each shaft doors 11 are arranged. At each shaft door 11 at least one sensor 17 is arranged, which is connected with an assigned bus node 18, wherein the bus node 18 are connected via a data bus 22 to a control unit sixteenth The sensors 17 to the levels A, B and C are each formed as a power switch, which are closed with actuation. The control unit 16 controls the elevator installation 10 and is for this purpose connected to the drive unit 14, the cab controller 19 and via the data bus 22 and the bus node 18 with their associated sensors 17th The sensors 17 form a so-called safety chain. The control unit 16 may also be a door monitoring unit or simply a monitoring unit.

Figure 2 shows a monitoring system for the control of the elevator system 10. The monitoring system includes sensors 17 which are each connected to a voltage supply line Vcc and to the assigned bus node 18th The bus nodes 18 are connected to the data bus 22 and thus connected to the control unit sixteenth In the embodiment shown in Figure 2, the sensors 17 are particularly easily formed, because the sensors 17 are each composed of only the power switch, which is closed at closed shaft doors 11 and thereby the connected bus node connects 18 to the power supply line Vcc. This gives the bus node 18, the required converters for operating power supply and can be either the state of the sensor 17 transmitted automatically to the control unit 16 or 16 transmit its state at the next interrogation of the control unit. If a shaft door 11 is not closed properly, the power switch in the sensor 17 remains open and the respective bus node 18 of the sensor 17 energized at this shaft door 11, so that it can not transmit to the control unit 16 changes its state and / or the state of the associated sensor 17 and is recognized in this way by the control unit 16 to be defective.

Next, the operation of the safety chain formed by the sensors 17 will be described. Elevators are known to high security standards. To meet these safety standards, is 12 queried the status or condition of the safety chain in the elevator shaft 15 prior to movement of the elevator car. The bus node 18 can thereby be designed as an active bus node 18 and therefore autonomously at predeterminable states of the elevator installation 10 their condition to the control unit 16 to send. Alternatively, the bus node 18 can also be formed and passively transmit the status of the bus node 18 and / or the associated sensor 17 by means of a polling process to the control unit sixteenth For this, each bus node 18 is prompted for a given time by the control unit 16 to transmit its condition.

The control unit 16 accepts the conditions to be checked sensors 17 against, evaluates them and initiates appropriate control actions. The elevator car 12 can be moved, for example, only when all the sensors Show 17 closed shaft doors 11 and cabin doors. 13 In the illustrated embodiment, only the sensors 17 to the shaft doors 11 on each floor A, B and C are shown to maintain clarity. Furthermore, the elevator system 10 and in particular the safety chain contain other sensors not shown. For example, the top and bottom floor A and C respectively be disposed limit switches, which prevent fly over the floors beyond. Likewise, 12 one or more sensors can be attached, indicating the state of the car door 13 on the car door 13 of the elevator car.

The voltage supply of the bus node 18 is controlled in dependence on the states of the sensors associated with the seventeenth It is thereby achieved that the respective bus node 18 changes its state or of the associated sensor 17 only to the control unit 16 transfers, when the sensor 17 indicates a fault-free state. Assigns a sensor 17 a fault condition on the bus node 18 remains de-energized and can not report this condition. The control unit 16 recognizes, however, anyway, that in this sensor 17 is present on a particular floor of an error, as the status signal from this sensor 17 fails. This can avoid that the bus node 18 in spite of a functional state of the sensor 17 a fault condition to the control unit 16 notifies.

The control unit 16 detects the corresponding error in the safety chain and can take appropriate measures. The simplest measure is an emergency stop of the elevator car 12. However, it may also be a forced drive of the elevator car 12 at a reduced speed to the ground floor to be initiated or a service center can be informed. It is also possible to register a sensor error 17 the safety chain in an error log, which is stored in a memory of the control unit 16, can be so that when the next maintenance of the elevator system 10 corrected the errors or controlled. A particular advantage of this embodiment of the safety chain, the ability to clearly identify the faulty sensor 17 or bus node is 18. When the transmission of the state of the sensor 17 or the bus node 18 of the bus node 18 transmits a unique identification so that the controller 16 to place the can detect the error and take appropriate action. If an error occurs on the car doors 13, the control unit 16, for example, try the car doors 13 to close again by the car controller 19 is instructed to open the doors again and close.

In the safety chain and position sensors can be integrated, it is determined which, if the elevator car 12 reaches a corresponding allowable position in the elevator shaft 15, and the doors can be 11, 13 open. If from such a position sensor, a status message is absent, which may be that the elevator car 12 has not yet reached the prescribed off position. The control unit 16 detects this condition and try the elevator car 12 to move to a corresponding allow exit position at which the position sensors associated bus nodes 18 on, so that the state message may be reported on the error-free state of the position sensor to the control unit 16th

The monitoring system may also include sensors 23, which are formed for example as a switch or as Hall sensors. Figure 3 shows a switch configured as a sensor 23, which is opened with actuation. In this case, the connection to the voltage supply line Vcc is closed in the closed shaft doors 11, so that the assigned bus node 18 is supplied with power and can transfer its state to the control unit sixteenth If the shaft doors 11 is opened, the power supply is interrupted and the bus node 18 can not issue incorrect status message.

The sensors 17, 23 may also be formed without contact. For example, proximity sensors can be used which react to an electronic or magnetic field. In this case, the connection is interrupted for voltage supply Vcc, for example, when no magnetic field is detected. If the hoistway doors 11 closed, a magnetic field is opposite from the shaft door 11 is detected and the power supply line Vcc in the sensor 17 is connected to the bus node 18th

The sensor 17 can also be designed as a Hall sensor. In this case, the supply voltage Vcc of the bus node 18 is electronically controlled in the sensor 17, in such a way that the bus node 18 remains deenergized when the sensor 17 an unsafe or erroneous state is detected.

Furthermore, it is possible to use several sensors 17 to connect with a bus node 18, when for example in the security chain redundancy is required. Here, too, has an electronic evaluation of both conditions occur, so that the bus node 18 is only connected to the power supply Vcc when the redundant sensor 17 assumes at both sensors a safe state, or the power supply Vcc is already interrupted when only one the two sensors having an unsafe condition.

The transmission method used on the data bus 22, a Token Ring is realized. When Token Ring method a (virtual) ring of a bus node 18 is passed on to the next. The individual bus node 18 transmit its status message upon receipt of the ring and then give it to the next bus node 18 on. If the ring back in the control unit 16 detects the control unit 16 that all bus nodes have 18 cast their status message. A similar method provides that the control unit 16 monitors whether it receives from all bus nodes 18 a status message within a predefined period of time, for example, 5 ms.

Datenbusmedium than conventional copper wires, but also wireless radio links, optical fiber or other suitable communication media can be used.

The design of the lift system 10 ensures a safety chain, which is designed so that no wrong transmission of the existing state of the sensor 17 may occur through the bus nodes 18th Is also possible by the employed bus node 18 an identification of the fault location. It can be prevented that a bus node 18 incorrectly detects a dangerous or defective condition or not delivered. With the identification of the bus node 18 ensures that no other bus nodes 18 under a false address undetected can issue a status message to the control unit 16th It can be excluded that, for example, the bus node 18 on floor B on behalf of Busknotenknotens 18 reports on Floor A that the bus node 18 on floor A is correct because the bus node 18 on floor A loses power due to an open contact and not can respond more.