HK1087570B - Method and device for monitoring elevator areas - Google Patents

Description

Method and device for monitoring the range of an elevator installation

Technical Field

The invention relates to a device for monitoring the range of an elevator, to a method for monitoring the range, and to a software module for monitoring the range.

Background

The elevator system has at least one elevator car which moves along a conveyor in the elevator shaft or exposed to the outside. Usually the elevator car is moved from floor to floor so that a person can step on or off the floor or so that loading or unloading can take place on the floor.

The space inside the elevator car, but also including the access area arranged in front of the elevator shaft, is a particularly important place since the personal safety of personnel can be threatened e.g. in the event of a failure of the elevator. For example, the shaft door is opened even though the elevator car is not behind the shaft door to be opened. For example, jamming can occur in the area of the door.

It is also conceivable that incorrect actions by personnel, incorrect operation of the elevator or unprofessional loading or unloading of the elevator cause problems.

There is a trend towards monitoring these important areas so that problems can be identified in advance and in particular injury to personnel can be avoided.

Monitoring of elevator doors is typically accomplished using mechanical, magnetic, inductive or similar switches. Further, an optical system such as a diaphragm or a grating may be used. This measure makes it possible to provide the elevator control with certain information, for example, about the situation of a closed door. However, the content of the information is relatively limited, since the switch can show only two conditions (digital information with the door closed or open), for example. This monitoring solution is limited primarily to the direct range of the car and/or the shaft door.

To create an integrated monitoring system, a combination of, for example, multiple switches and gratings is required.

Optical systems in particular have certain advantages, since they operate in a contactless manner and are not affected by mechanical wear, in contrast to mechanical solutions. Unfortunately, even in the more complex optical systems employed in elevators, their effectiveness is limited to a few states and their coverage is further limited. For example, it can be detected whether a person remains within the range of the door, and a movement can be recognized. However, such optical systems do not reliably monitor a large spatial area. Moreover, the reaction time of such diaphragms is approximately 65 milliseconds, which in some cases is too long.

Certain optical sensors may even enable the acquisition of three-dimensional images, wherein mechanically moving parts as mirrors may be employed, for example. But such sensors are complex and expensive.

In international patent application WO01/42120 a system for monitoring elevator doors is disclosed, which works with a pre-programmed processor, a digital camera, an analog camera or a video camera. The camera provides a sequence of two-dimensional images, and information about the condition of the elevator door is obtained by comparing said images. The system operates with external light that is captured and received by the camera. A problem arises when this external light changes drastically, for example in the sun, and thus the image brightness will increase drastically.

Conversely, the use of such cameras for the above purpose also presents problems when the existing external light is insufficient. It is important in monitoring the range that the monitoring must be secure and reliable in all cases. The dependence on external light is a problem for this consideration. According to the international patent application, typical pattern recognition measures (pattern adaptation) are used in order to be able to evaluate two-dimensional image sequences. A system according to said PCT patent application working with two-dimensional images cannot make an explanation about the distance. Furthermore, in such two-dimensional systems, only a certain specification of the movement and the direction of movement can be derived by intensive computational reprocessing of the images provided.

Another monitoring system is disclosed in US 5387768. In the system a camera is used whose image is processed in a costly manner in order to make an explanation as to whether and how many people are in the range of the elevator. The camera takes successive shots with different focal length adjustments in order to derive therefrom an indication about possible movements.

In US patent 5345049 an elevator is disclosed, in which infrared sensors are used to detect whether one or more persons are waiting in the area of the passage of the elevator. Wherein the number of persons is not determined here.

Three-dimensional semiconductor sensors are known which allow three-dimensional acquisition of image information. Such a sensor is disclosed, for example, in the article "fast range imaging by multiple double short-time integration (MDSI) using a CMOS sensor matrix", P mengel et al, siemens ag, department of joint technology, munich, germany. Such three-dimensional semiconductor sensors are used for spatial monitoring. This is the closest prior art to the present invention.

Another example is described in the article "CMOS photosensors for three-dimensional imaging using pulsed lasers", R-yerimasis et al, 2001IEEE international conference on solid state circuits conference, page 252.

Elevator systems with access right checking are known. Such systems operate, for example, with tags and tag readers. It is thus possible to check whether the person has the right to use the elevator. Only identified persons with a marking are able to call the elevator car and select a destination floor. Such a system can work reliably in this respect. But with this measure it is almost impossible to verify who and how many people enter the elevator. The entering person is checked by corresponding design measures, such as a cross-shaped revolving door, an entrance gate or other design measures. However, these measures are expensive to implement and often less desirable for aesthetic reasons.

The use of current identification systems for elevator use therefore does not guarantee that only authorized persons can enter the elevator car or leave it at a floor to which they have access.

Disclosure of Invention

The object of the invention is to propose an improved elevator.

The object of the invention is to achieve an accurate and reliable range monitoring of an elevator.

Another object of the invention is to achieve reliable and rapid problem identification for elevators.

According to one aspect of the invention, there is provided a method of monitoring an entrance area of an elevator installation, the method comprising the steps of: emitting a light pulse with a light source; detecting light pulses reflected by an object with a plurality of photosensitive devices, the object being disposed in a surveillance area, the plurality of photosensitive devices forming a sensor group of sensors; determining three-dimensional image information by calculating a distance between the sensor and the reflecting object based on the propagation time and/or phase of the reflected light pulse; and evaluating the three-dimensional image information for identifying the state.

According to another aspect of the invention, there is provided a method of monitoring the interior of an elevator car, the method comprising the steps of: emitting a light pulse with a light source; detecting light pulses reflected by an object with a plurality of photosensitive devices, the object being disposed in a surveillance area, the plurality of photosensitive devices forming a sensor group of sensors; determining three-dimensional image information by calculating a distance between the sensor and the reflecting object based on the propagation time and/or phase of the reflected light pulse; and evaluating the three-dimensional image information for identifying the state.

According to a further aspect of the invention, a method is provided for monitoring a door zone of an elevator installation, comprising the following steps: emitting a light pulse with a light source; detecting light pulses reflected by an object with a plurality of photosensitive devices, the object being disposed in a surveillance area, the plurality of photosensitive devices forming a sensor group of sensors; determining three-dimensional image information by calculating a distance between the sensor and the reflecting object based on the propagation time and/or phase of the reflected light pulse; and evaluating the three-dimensional image information for identifying the state.

According to a further aspect of the invention, a device for monitoring a region of an elevator installation is provided, which device comprises a three-dimensional semiconductor sensor for detecting three-dimensional image information and is designed to carry out the above-described method.

Drawings

The invention will be further explained below by way of example with reference to the accompanying drawings. The figures show that:

fig. 1A, 1B are schematic side views of an elevator car having a sensor of the present invention;

FIG. 2 is a block schematic diagram of a sensor of the present invention having a processing unit;

fig. 3 is a side schematic view of an elevator car having a sensor of the present invention;

FIG. 4 is a schematic flow chart of the present invention;

fig. 5A, 5B are diagrammatic top views of an elevator car with a sensor according to the invention and a device according to the invention together with the extent of a shaft;

FIG. 6 is a block diagram of the software modules of the present invention.

Detailed Description

According to the invention, a novel optical three-dimensional sensor is used in the elevator range for the first time. It preferably relates to a three-dimensional sensor operating in the infrared range. A three-dimensional sensor comprising an optical transmitter for transmitting light in a pulsed manner and a CMOS sensor group for receiving light is particularly suitable. It is preferably a light-emitting diode or laser diode which emits light in the infrared range, wherein the light is emitted in the form of short pulses (instantaneously). For this purpose, the diodes preferably have an (electronic) shutter which interrupts the emitted light. But the diodes can also be pulsed directly. The sensor group functions as an image sensor that converts light into an electrical signal. Preferably, the sensor group is formed by a plurality of light-sensitive elements. The sensor group is connected to a processing chip (for example a CMOS sensor chip) which determines the propagation time of the transmitted light, wherein a special integration method (multiple double short-time integration, also referred to as MDSI) is implemented. Wherein the processing chip simultaneously measures the distance to all destination points in space within a few milliseconds. A spatial resolution of 5mm can typically be achieved.

In addition to the three-dimensional sensors described above, another three-dimensional sensor used in connection with the invention is based on the principle of distance measurement, by means of which the propagation time of the transmitted light is determined from the phase of the light. In which the phase at which the light is emitted and the phase at which the light is received are compared and the elapsed time or the distance to the reflecting object is determined by the comparison. For this purpose, a modulated optical signal is preferably transmitted instead of the short optical pulses.

In order to suppress the influence of the external light, a double sampling method may be employed in which sampling is performed once with light and once without light. In which two electrical signals are obtained (once with active illumination and once without illumination), the final signal being obtained by subtracting the two signals, said final signal being unaffected by external light. Such a sensor can operate reliably even in the sun and in the event of changes in the influence of light.

Preferably, the three-dimensional sensor is implemented by a semiconductor device, which increases reliability and robustness. Moreover, such three-dimensional sensors are particularly small and advantageous for mass production.

By means of three-dimensional detection, a device can be realized which directly detects the position of a person or other object, the distance between them and even their movement and direction of movement. For this purpose, spatial mathematical operations can be carried out using a processing unit (for example a personal special-purpose computer or a central processing unit with peripheral devices). This spatial mathematical operation is very different from the special pattern recognition methods used up to now, which work with different gray gradients, for example.

Fig. 1A and 1B show a first embodiment of the device according to the invention as a sectional view. This relates to a device for monitoring the range, in which the inner range of the elevator car 12 is monitored in the present example. The device comprises a three-dimensional semiconductor sensor 9 which is arranged in the region of the upper side of the elevator car 12 to be monitored, so that the interior space of the car 12 is at least partially in the detection region 17, 18 of the sensor 9. To show the sensor more clearly, the sensor is shown larger than it actually is. The sensor 9 includes a laser diode 10 as a light source and transmitting a spontaneous light component. In each case, an irradiated area, for example a light cone 17, is produced as a function of the beam shaping. A sensor group 11 is provided which acts as an image sensor and receives light information via a light cone 18 and converts it into an electrical signal. The optical information is processed and converted into image information (e.g., a three-dimensional distance image) by the processing chip 19. Such a three-dimensional distance image 16 is illustrated schematically in fig. 1A. From this three-dimensional distance image 16, it can be concluded that the car 12 is empty. The car doors 13 and 14 are closed. In fig. 1A it is schematically illustrated that the distance image 16 is a three-dimensional image of the elevator car 12.

When this detection process is repeated at a later point in time T1, the range image 16 shown in fig. 1B results. The distance image 16 shows that there are a total of four people 31, 32, 33 and 34 in the car 12. The distance image 16 is a three-dimensional image of the elevator car 12 and the persons 31-34.

The laser pulses sent to car 12 are preferably synchronized with respect to the start of the integration window. The laser pulses received by the sensor group 11 after reflection in the car 12 trigger a linearly increasing sensor signal x (T) after a propagation time T0, which can be measured, for example, at integration time points T2 and T3. While the integration time windows T2 and T3 are active, only a small fraction of the original intensity of the light pulse is detected from the distance of the light source 10 from the different spatial points and from the spatial points to the sensor set 11. The position and slope of the integrated intensity signal x (T) can be found by, for example, two integral measurements taken at different times T2 and T3 (where T0 < T2 < T3). The travel time T0 and thus the distance to the person or object can thus be determined with precision. Information that is not currently available in other ways can be obtained by the processing chip 19 using this method of evaluating the light information.

Part of the processing is performed in the processing chip 19, rather than only in a single processing unit. I.e. a part of the processing is implemented by corresponding hardware and is thus reliable and fast.

Two different treatment methods may be employed. In the first processing method of the present invention, the sensor group includes n photosensitive devices (n > 0). Each of these photosensitive devices provides an intensity signal x_n(t), the intensity of the intensity signal being dependent on the intensity of light received by the respective light-sensing device. These intensity signals x_n(t) are combined into an intensity signal x (t), for example by superposition. After the integration, the above-described evaluation is carried out, wherein the time T0 is determined from the position of the intensity signal x (T) and the gradient of the increase. In this embodiment, since a plurality of photosensors are evaluated in common, the area resolution of the apparatus is reduced. Nevertheless, the travel time and thus the location of the object to be monitored can be determinedThe distance of the reflective object within the range. A three-dimensionally operating sensor device is thus achieved, which has a better depth-of-field resolution than area resolution.

According to a second method of the invention, the sensor group likewise has n photosensitive devices (n > 0). Each of these photosensitive devices provides an intensity signal x_n(t), the intensity of the intensity signal being dependent on the intensity of light received by the respective light-sensing device. For these intensity signals x_n(t) the above evaluation is carried out for each intensity signal x_n(t) are processed separately (preferably simultaneously). From intensity signal x_n(T) determining the corresponding time T from the position and the gradient of growth_n0. The preferred processing chip has a plurality of parallel channels (preferably n channels) for n intensity signals x_n(t) processing. In the present embodiment, since a plurality of points in space (for example, a plurality of points of an object in a monitored range) are detected, the area resolution is realized. The propagation time T can be determined for each of these points in space_n0 and then the distance is determined. A three-dimensionally operating sensor device with depth-of-field resolution and area resolution is thus achieved.

The device according to the invention, as shown in fig. 2, also has a processing unit 20, which is connected to the sensor 9, for example by a communication link 21. The communication connection 21 is used to transmit electrical signals representing image information (also referred to as status information) from the sensor 9 to the processing unit 20. The device also has a power supply 22 (e.g. a voltage source) for feeding the sensor 9. The image information is evaluated by the design of the installation processing unit 20 of the software module in order to realize the range monitoring.

According to one embodiment, the evaluation of the image information is continued with the processing unit 20 in order to obtain information about the status of the monitored range. For this purpose, the state information obtained from the image information is compared with the setpoint information, for example. For this purpose, the processing unit 20 comprises means for providing rating information. For example, a hard disk internal memory is involved. The distance image 16 shown in fig. 1A may be stored as rating information in a hard disk memory, for example. The processing unit 20 can determine whether the status information obtained corresponds exactly to the target information using the comparison algorithm. If this is the case, the car interior space is empty.

Other setpoint information can also be specified, which the processing unit 20 uses to perform the respective comparison. For example, for each type of desired information, there is a reaction associated with it.

According to another embodiment of the invention, the processing chip 19 processes the image information in a hardware manner and the processing unit 19 then evaluates it without a comparison of the status information with the setpoint information. In which the image information acquired by the sensor 9 at least at two temporally successive points in time are compared with one another. Such a comparison can be performed, for example, by a corresponding computational superposition of the images. By subtracting the image information at time t equal to al from the image information at time t equal to 0, the processing unit 20 can recognize the change in the three-dimensional space.

Another embodiment of the present invention is shown in fig. 3. Shown in fig. 3 is a full-scale sensor 39. The sensor is arranged in the upper region of the elevator car 42 and covers the monitored interior of the car 42 from above as indicated by the small arrow in the vicinity of the sensor 39. For example, in the elevator car 42 there is an object 41 which is in the close proximity of the open car door. The apparatus of the present invention can recognize whether the car door is in an open state because a large difference in brightness occurs when the door is opened. The sensor 39 is connected to a processing unit 50, which comprises a corresponding software module. The entire device is designed such that in a first step it can be detected whether there are persons and/or objects inside the car 42. If this is the case, classification categories are performed in the next step. The classification category may enable the device to initiate a reaction that is appropriate to the state. In the example shown, the device according to the invention can recognize whether there are persons and/or objects in the elevator. The device recognizes, on the basis of the clear rectangular geometry, that an object 41 is involved. The device of the invention can then, for example, attempt to identify the position of the object 41 in the car 42, in order to be able to derive a response therefrom. In the example shown the item 41 is very close to the open door. In possible response, an audible warning is emitted via the loudspeaker 51, in order to request the person loading the elevator to move the object 42 further into the interior of the car 42. As long as this is not achieved, the device of the invention will interrupt the closing of the door.

As shown by way of example in fig. 4, the method of the invention for range monitoring comprises a plurality of method steps. Light reflected at different points in space within the range being monitored is collected by a sensor (e.g., sensor 9 in fig. 1A) (block 61 in fig. 4). The light rays come from a light source (e.g., light source 10 in fig. 1A). Distance information is derived from the collected light (block 62 in fig. 4). In which the propagation time of the light is taken into account. To achieve this, synchronization is performed between the light source and the sensor group. This step is preferably performed on a dedicated processing chip (e.g., processing chip 19 in FIG. 1A). The distance information is then evaluated (block 63) to identify the range being monitored. In a processing step (block 64), the processing unit determines whether a person is within the monitored range. If this is not the case, a determination is made as to whether an item is within the monitored range (block 65). When a person is identified within the monitored range, the flow chart is branched. The classification categories may be performed in a next step 68. Some examples of classification categories are listed below:

the number of the persons is calculated,

the location of the person within the monitored range is identified,

the movement or the direction of movement is detected,

the right of entry is checked and,

checking whether the number of persons in the monitored range exceeds a predetermined value, etc.

One or more of the following exemplary listed reactions may be initiated in step 69, depending on the classification category, respectively:

waiting until all other persons step on the elevator,

the elevator does not move and/or a broadcast announcement is given when overloaded,

when one or more persons stay near the door, waiting until the situation changes, or sending out broadcast notice,

when the person moves in the direction of the door, a corresponding adaptation adjustment is made to the opening or closing process of the door (for example stopping the closing of the door or slowing down the closing process of the door),

a broadcast notification is issued or an alarm is activated when an unauthorized elevator user is present in the car.

When the apparatus of the present invention detects an item within the car, then classification categories may be performed in another step 66. Some examples of classification categories are listed below:

the number of the objects is determined,

the kind of the object is determined,

the size of the object is determined,

the position of the object within the monitored range is identified,

the movement or direction of movement of the object is detected.

One or more of the following exemplary reactions may be initiated in step 67, depending on the category, respectively:

the elevator does not move and/or a broadcast announcement is given when overloaded,

when one or more items are located near the door, waiting is performed until the situation changes, or a broadcast announcement is sent,

when an object is moved in the direction of the door, corresponding adaptation adjustments are made to the door opening or closing process (e.g. stopping the door closing or slowing down the door closing process).

When neither a person nor an item is detected, the flow chart is branched back to the beginning by the branch 60 and the whole process is repeated again. According to the present flowchart, an arbitrarily branched decision tree can be implemented in order to finally automatically initiate a reaction corresponding to and adapted to the prevailing situation.

The method steps are preferably implemented in a processing unit, in which a corresponding software module is used. It is preferable to use a spatial mathematical operation in evaluating the distance information.

In addition to monitoring the range, the functionality of the processing unit can be extended to allow the following door states to be identified:

the door gap is arranged at the position of the door,

the position of the elevator door or doors,

the closed state of the elevator door is,

objects within the confines of the elevator door.

A state-adapted reflection is then initiated by the processing unit in dependence on the recognized door condition.

Wherein one or more of the following reactions are involved:

the closing process of the door is stopped and,

the opening process of the door is stopped and,

the closing process of the slowing-down door is performed,

the opening process of the slowing door is put down,

a speaker announcement is initiated and the speaker announcement is initiated,

a call for maintenance is made,

the emergency call is started and the emergency call is started,

the operation of the elevator is stopped and,

the speed is slowed down to continue the elevator operation,

the evacuation of the people of the elevator car is started,

and the like.

The device according to the invention can recognize one or more of the following situations:

the number of passengers in the elevator car or in the area of the passage in front of the elevator shaft (lobby),

the number of people getting on or off the ladder,

the direction of the flow of the people is,

the overload is caused to occur to the outside,

the loading is not proper, and the loading is not proper,

an obstacle is arranged in the range of the door,

the detection of the need is carried out by the user,

the movement is carried out in such a way that,

the door gap is arranged at the position of the door,

the position of the door of the elevator,

door closed condition of elevator and

objects within the confines of the elevator door.

The device of the invention according to embodiments may initiate one or more of the following reactions, respectively:

as long as the elevator car has people in the passage range of the floor where the elevator car is located, the elevator door is not closed,

the elevator car is controlled in dependence on the situation so as to take into account the increase in the number of people on the respective floor.

When a person waits within the range of the shaft of a corresponding floor, the elevator car stops only at that floor,

when a person approaches the shaft door and does not move at the shaft door, the automatic calling of the elevator car is realized,

control is effected in dependence on the passenger flow or on demand, for example in an elevator installation with a plurality of elevator cars,

when a problem is identified or personnel safety will be threatened, emergency measures are enabled,

the display information and/or the broadcast announcement,

allowing access to a floor or prohibiting access to a floor,

the use of the elevator car is permitted or prohibited,

for example, the number of people and the frequency of use are statistically evaluated,

pay elevator functionality.

Another embodiment of the present invention is shown in fig. 5A and 5B. This involves a monitoring device for the access area in front of the elevator shaft. In the top view of fig. 5A, an elevator car 82 is shown, which rests on one floor of the building. The car 82 is separated from the passage range by car doors 87, 88 and shaft doors 89, 90. Doors 87-90 are shown slightly open. On the wall beside the elevator there is a sensor 79 according to the invention, which is connected to a processing unit 80. A speaker 81 is provided through which an announcement is made. The extent of the passage is bounded on both sides by walls 85 and 86. The figure shows the case where there are three persons 82, 83, 84 in the area of the passage. The persons 82 and 83 stand directly in front of the doors 87-90 and wait until the doors are opened. The other person 84 moves away from the doors 87-90 as indicated by the arrows. The device of the invention can collect this condition. The apparatus produces a three-dimensional range image 76 shown schematically in fig. 5B. The device recognizes that three persons are within the range of the passageway. In addition, the device can monitor whether the persons 82 and 83 are particularly proximate to the open doors 87-90. If the situation is the case, the opening movement of the door is stopped, so that the phenomenon of threatening personal safety is avoided. Once the doors are fully opened, personnel 82, 83 can enter the elevator cab 82. But also the process can be monitored. Once both persons 82, 83 have fully entered the elevator car 82, the doors 87-90 are automatically closed. The device also detects the person 84, but the elevator car does not wait for the person 84 as the person 84 moves away from the door.

The described embodiment can be extended in that the software of the processing unit 20, 50, 80 is designed such that the processing unit can not only identify the presence and location of persons and/or objects, but also classify the objects or persons.

The embodiment shown can be extended in that a plurality of temporally successive image sequences are supplied to the processing units 20, 50, 80. The processing unit 20, 50, 80 can determine the direction and/or speed of movement of the person and/or object by appropriate processing of the image information, in addition to a pure detection of the person and/or object. The movement information may be employed in order to initiate a reaction to the state adaptation. When, for example, the processing unit 20, 50, 80 finds that a person is moving slowly and the elevator doors are closed, the closing of the elevator doors can be interrupted or the closing movement can be stopped. When a fast moving person is involved, this may be sufficient to slow down the closing movement or to interrupt the closing movement only for a short time, for example. As a further reaction it is also conceivable to initiate an announcement in order to ensure that no persons remain within the door.

As shown in fig. 1A and 1B and 3, the device according to the invention can be used for monitoring the interior of a car and the car and shaft doors.

If it is desired to monitor the interior space of the elevator car first, the sensors installed in the area of the car roof are identified as in fig. 1A, 1B and 3.

If the sensor is arranged on the rear wall of the car, i.e. in the region of the wall opposite the car door, then not only the interior of the car can be detected when the door is opened, but also the region of the front hall of the car can be detected through the opened door.

In the configuration shown in fig. 1A, 1B and 3, the sensor moves with the elevator car from one floor to another. If there is no car at the relevant floor, the shaft door of the respective floor and the access range of the floor are not monitored by the sensor on the car. It is suggested to use the sensor of the present invention at each floor as shown in fig. 5A.

There are of course many other solutions in which one sensor or a plurality of sensors are provided.

It is generally necessary to take care when installing the sensor that it should be as impervious to external influences (objects and/or persons, weather conditions, mechanical damage, etc.) as possible.

A software module 90 for use in an elevator processing unit is shown in fig. 6. Once the software module is called up and executed by the processing unit, the software module will perform the following steps:

evaluating distance information provided by a three-dimensional sensor of the monitored range to obtain a status of the range (submodule 91);

identifying whether there are people and/or objects within the monitored area (submodule 92);

status category (sub-block 93);

a state-adaptive response is initiated (sub-block 94).

Software module 90 may also include other modules.

Preferably the light source and the set of sensors are arranged in one housing. The light source is oriented with reference to the sensor group in a manual manner, so that the installation is facilitated. Orientation of the two components may be achieved at the time of fabrication or pre-installation.

According to another embodiment, the processing unit compares the image information with one or more reference images. For this purpose, the reference image can be subtracted from the image information, for example.

According to an improved embodiment, range monitoring can be achieved continuously by a plurality of light pulse sequences and their processing. The safety in the elevator range will be greatly improved compared to usual mechanical measures.

Since the sensors used are less susceptible to interference, the scope monitoring of the present invention is suitable for use both in building interiors and in outdoor applications. However, when applications are involved inside or outside buildings, an important aspect to be considered first is insensitivity to incoming light.

The scope monitoring according to the invention allows not only the identification of events but also the classification category. For example, the range monitoring can identify whether a person is in the range of the elevator car or whether there is a position in the elevator car for the person or object to be transported. It is even possible to determine the number of persons or objects and, for example, their size.

Another embodiment is characterized in that the use of range monitoring makes it possible to identify whether an elevator car is required at a specific floor. This can be achieved in such a way that the range monitoring monitors the range of the shaft on the respective floor. When a person approaches a shaft door and waits at the shaft door, the device determines that the person is waiting for the elevator car. This embodiment can even be extended, wherein the channel range can be divided into two regions. When a person waits in the zone of the upward movement, an elevator car situated on the upward path will stop. When a person is detected in a zone descending, the nearest car located on the descending path will stop. In this way, demand recognition and demand-dependent elevator control can thus be achieved. This embodiment has the advantage that the overall control of the operation of the elevator installation is possible without the usual call buttons having to be used. The whole system works in a completely contactless manner.

In the case of sensors connected to a processing unit using a usual communication connection, since the data (image information) transmitted from the sensor to the processing unit is of particular importance for security, corresponding measures are taken in order to ensure the security of the data transmitted over the communication connection which is not itself secure.

The device according to the invention is connected via a communication link and/or via a network to a processing unit (for example a computer) which processes, prepares and, if necessary, stores the image information provided by the sensor. The monitoring system can thus carry out centralized monitoring of an elevator installation with a plurality of elevator shafts, for example.

Preferably the arrangement of the invention is integrated in the safety circuit of the elevator. The safety circuit can thus be made more efficient and the elevator more reliable. Thereby the availability of the elevator can be improved. The corresponding design of the device of the invention can reduce the working failure rate.

The invention has the beneficial further design that the range monitoring can be expanded, and the anti-clamping protection can be realized. The anti-trap protection according to the invention makes it possible to detect persons in advance and to initiate corresponding reactions in order to reduce the risk of trapping in the region of the door.

Another advantage of the inventive solution with a three-dimensional sensor is that such a sensor has a short cycle time (< 20 ms). A very rapid monitoring scheme can be achieved. Critical conditions can be detected more quickly and reactions initiated in a timely manner. The invention makes it possible to implement a monitoring system whose reaction time to identify an object is only a few milliseconds. A rapid identification can initiate the corresponding reaction very rapidly.

The three-dimensional sensor adopted by the invention can realize the evaluation of the third dimension, which is better than a one-dimensional system (such as a diaphragm) or a two-dimensional system (such as a grating or a CCD camera). Range monitoring using three-dimensional detection allows to directly obtain close to actual images of the actual situation.

The advantage of using a semiconductor sensor is that the semiconductor sensor works with self-luminous components. The system is therefore substantially immune to environmental conditions and can operate even in the dark. Another advantage is that the invention can be implemented without the need for calibration mechanisms that are typically used in camera-based systems to account for changing environmental conditions. In systems based on cameras, for example, the sensitivity must be adjusted. The cost for this is eliminated in the present system.

Another embodiment of the invention is that the processing unit is designed to store the image information. The image information can thus be used to record critical processes, for example, in which a person is jammed when boarding or disembarking. This image information can serve, for example, as reliable evidence.

According to another embodiment of the invention, a maintenance call may be initiated in response to a problem being identified. In addition, emergency calls can sometimes be initiated in severe cases.

The evaluation of the image information provided by the three-dimensional sensor is preferably logically connected to the elevator control in order to synchronize the information processing. A control loop can thus be set up, which initiates a corresponding adapted reaction depending on the situation.

The advantage of the invention is that the waiting time can be shortened, since the control of the elevator can be adapted automatically to the changing conditions. It is thus possible to avoid the phenomenon that the car stops at a certain floor even though there is no person waiting at all at that floor.

According to a further advantageous embodiment of the invention, the scope monitoring of the invention is integrated with an access checking system. The check can thus be made automatically so that only authorized persons can use the elevator. This can be achieved, for example, when all authorized persons are equipped with a label. A person intending to enter the elevator must present the tag in front of the tag reader. The entry check counts the number of people who intend to enter the presentation marker of the next elevator car. The system of the invention can detect how many people actually enter the elevator when the elevator is stepped on. When the number of people in the car does not correspond to the number of people presenting the indicia, a reaction will be initiated. For example, the elevator can be left unmoved and announced, requiring the person to re-present the sign.

Also pay elevator measures can be implemented. All the people using the elevator must pay a certain amount. The number of people who have paid may be counted. When all people step into the car, the number of people is automatically counted. When a deviation occurs, corresponding measures can be taken. For example, a ride ticket check may be initiated.

Another type of pay elevator system is based on the use of keys or tokens with which the persons to be ridden declare. The statements are collected and the fees to be paid are billed to the respective persons, and when more persons are in the elevator than are collected, a corresponding reaction is initiated.

Claims (19)

1. A method of monitoring an entrance area of an elevator installation, the method comprising the steps of:

emitting a light pulse with a light source (10);

detecting light pulses reflected by an object arranged in a surveillance area with a plurality of light sensitive devices forming a sensor group (11) of a three-dimensional semiconductor sensor (9; 39; 79);

determining three-dimensional image information (62) by calculating a distance between the sensor and the object based on the propagation time and/or phase of the reflected light pulses;

and evaluating the three-dimensional image information for identifying the state.

2. A method of monitoring the interior of an elevator car (12; 42; 82), the method comprising the steps of:

emitting a light pulse with a light source (10);

detecting light pulses reflected by an object arranged in a surveillance area with a plurality of light sensitive devices forming a sensor group (11) of a three-dimensional semiconductor sensor (9; 39; 79);

determining three-dimensional image information (62) by calculating a distance between the sensor and the object based on the propagation time and/or phase of the reflected light pulses;

and evaluating the three-dimensional image information for identifying the state.

3. A method of monitoring a door zone of an elevator installation, the method comprising the steps of:

emitting a light pulse with a light source (10);

detecting light pulses reflected by an object arranged in a surveillance area with a plurality of light sensitive devices forming a sensor group (11) of a three-dimensional semiconductor sensor (9; 39; 79);

determining three-dimensional image information (62) by calculating a distance between the sensor and the object based on the propagation time and/or phase of the reflected light pulses;

and evaluating the three-dimensional image information for identifying the state.

4. The method of claim 1, wherein the method further comprises the steps of:

classifying the status (66; 68); and/or

A state-adapted reaction (67; 69) is initiated.

5. The method of claim 2, wherein the method further comprises the steps of:

classifying the status (66; 68); and/or

A state-adapted reaction (67; 69) is initiated.

6. The method of claim 3, wherein the method further comprises the steps of:

classifying the status (66; 68); and/or

A state-adapted reaction (67; 69) is initiated.

7. The method of claim 4, wherein the step of identifying the respective state (66; 68) comprises one of the following steps:

determining a number of one or more persons or objects present in the entry area;

identifying a location of one or more persons or objects in the entry area;

the movement and/or direction of movement of a person or object in the entrance area is detected.

8. The method of claim 7, wherein the first and second light sources are selected from the group consisting of,

wherein one of the following state-adapted reactions (67; 69) is initiated:

waiting until one or more persons or objects present in the entry area are stepped on before the elevator car moves;

waiting until the situation changes or a broadcast notification is issued if one or more persons or objects remain near the door;

if one or more persons or objects move in the direction of the door, an adaptation of the opening or closing process of the door is carried out.

9. The method of claim 5, wherein the step of identifying the respective state (66; 68) comprises one of the following steps:

determining the number of people or objects located in the elevator car;

checking whether the number of persons located in the elevator car exceeds an allowed number;

identifying a location of one or more persons or objects in an elevator car;

the movement and/or direction of movement of a person or object in the elevator car is detected.

10. The method according to claim 9, wherein one of the following state-adapted reactions (67; 69) is initiated:

preventing elevator car movement and/or issuing a broadcast announcement when the number of people in the elevator car exceeds an allowed number;

if the person stays near the door range, waiting until the condition changes or a broadcast notice is sent out;

if the person moves towards the door direction, the opening or closing process of the door is adjusted in a matching mode;

if an unauthorized elevator user is present in the elevator car, a broadcast announcement or an activation alarm signal is issued.

11. The method of claim 6, wherein the step of identifying the respective classification status (66; 68) comprises one of the following steps:

identifying whether a person or object is in the region of the elevator door;

identifying a position of an elevator door;

the closed state of the elevator door is monitored.

12. The method according to claim 11, wherein one of the following state-adapted reactions (67; 69) is initiated:

stopping the closing of the door or the opening process of the door;

slowing the closing of the door or the opening process of the door;

if the person stays near the door range, waiting until the condition changes or a broadcast notice is sent out;

if the person moves towards the door direction, the opening or closing process of the door is adjusted in a matching mode;

a maintenance call is placed or an emergency call is initiated.

13. The method of claim 12, wherein the first and second light sources are selected from the group consisting of,

wherein the three-dimensional images are compared and one of the compared images is an image provided by the memory.

14. The method of claim 12, wherein the first and second light sources are selected from the group consisting of,

wherein the three-dimensional images are compared, one of the compared images being one of the images detected by the sensor group (11) in time succession.

15. The method of claim 14, wherein the first and second light sources are selected from the group consisting of,

wherein the evaluation method is carried out by a processing unit for evaluation, said evaluation method being based on a three-dimensional mathematical operation.

16. The method of claim 15, wherein the first and second light sources are selected from the group consisting of,

wherein the light source (10) emits light pulses in the infrared range.

17. The method of claim 16, wherein:

the light source is a light emitting diode or a laser diode.

18. The method of claim 17, wherein the first and second light sources are selected from the group consisting of,

wherein the sensor group (11) is an image sensor, and the image sensor is connected with a CMOS processing chip.

19. A device for monitoring the area of an elevator installation,

the device comprises a three-dimensional semiconductor sensor (9; 39; 79) for detecting three-dimensional image information and is designed for carrying out the method of claims 1 to 18.