EP2700603B1 - Method for determining the position of a lift car and corresponding device - Google Patents

Description

The invention relates to a method for determining the position of an elevator car and the corresponding device.

In order to comply with the standards in force, the elevator cabins must provide users with visible information, and audibly with information on the position of the cab at each floor, and in particular a explicit information on the arrival floor.

To know the position of the cabin, it is known to have the position sensors of the cabin at each floor level, or to have in the elevator shaft notched strips read by sensors connected to the cabin.

These known solutions are accurate and reliable, but require extensive wiring and complex placement over the entire height of the elevator shaft.

In addition, for the renovation of old installations, interventions in the control cabinet are complex. As a result, the upgrading of an old installation often results in the replacement of the control cabinet, and the corresponding costs.

GB2063521 shows a process that uses cabin position sensors on each floor. US2006118364 shows a method that uses a notched strip disposed along the well and read by a sensor linked to the cabin.

One of the aims of the invention is to propose a method for determining the position of an elevator car which does not call for a permanent installation in an elevator shaft.

Another object of the invention is to provide a connecting device between the control cabinet and the elevator car, which allows the compliance of old lifts to the new standards by limiting the replacement to the single button box of the cabin.

Yet another object of the invention is to provide a connecting device between the control cabinet and the cabin which reduces the number of cables required.

• au stator du moteur, on mesure l'énergie consommée par le moteur et le nombre de tours du champ tournant statorique ;
• à partir du glissement du rotor du moteur et des mesures de l'énergie consommée par le moteur et du nombre de tours du champ tournant, on calcule la distance parcourue par la cabine, et
• on détermine la position de la cabine par rapport à un niveau de référence.

The invention relates to a method for determining the position of an elevator car driven by an asynchronous motor, characterized in that , for a displacement of the cabin:

• at the motor stator, the energy consumed by the motor and the number of revolutions of the stator rotating field are measured;
• from the sliding of the rotor of the engine and the measurements of the energy consumed by the engine and the number of revolutions of the rotating field, the distance traveled by the cabin is calculated, and
• the position of the car relative to a reference level is determined.

Advantageously, the measurements of the energy consumed by the motor and the number of revolutions of the stator rotating field are performed on a phase wire of the stator.

Preferably, the measurements on a phase wire of the stator are carried out by means of a ferrite ring.

Advantageously, the measurement of the energy consumed by the motor comprises the measurements of the voltage, the current and the phase shift between voltage and current.

Advantageously, the sliding of the rotor is determined during a calibration phase comprising a rise of the cabin from a reference level to the highest level, and a descent of the cabin from the highest level to the next. at the reference level, by measuring, between the descent and the climb, the differences in the number of revolutions of the rotating field and the energy consumed by the engine, to deduce a ratio of the slip in relation to the energy consumed.

Preferably, during a learning phase, the distances between the car and the reference level corresponding to the height positions of the stages are stored.

Advantageously, to calculate the distance traveled by the cab, from the number of revolutions of the rotating field and the slip, the speed of rotation of the rotor is calculated, the speed of movement of the car and the distance traveled by the cabin.

Advantageously, with each passage of the cabin at the reference level, a synchronization is provided for the determination of the position of the cabin. The invention also relates to the use of the method described above for triggering the announcement of floors.

• dans la cabine d'ascenseur, une boîte à boutons équipée de moyens de multiplexage/démultiplexage et de moyens d'annonce visuels et sonores ;
• près de l'armoire de manoeuvre, un boîtier de liaison entre armoire de manoeuvre et cabine d'ascenseur ;
• et entre la boîte à boutons et le boîtier de liaison, une ligne de communication série.

The invention also relates to a device for implementing the method described above, characterized in that it comprises:

• in the elevator car, a button box equipped with multiplexing / demultiplexing means and visual and audible announcement means;
• near the control cabinet, a connection box between control cabinet and elevator car;
• and between the button box and the link box, a serial communication line.

• des moyens de mesure, sur un fil de phase du stator du moteur d'entraînement de la cabine, de la tension, du courant, du déphasage entre tension et courant, et de la fréquence du champ tournant statorique,
• des moyens de calcul du glissement du rotor, de la vitesse du rotor, de la vitesse de la cabine, et de la position de la cabine par rapport à un niveau de référence,et
• des moyens de multiplexage/démultiplexage pour assurer une communication parallèle avec l'armoire de manoeuvre et une communication série avec la boîte à boutons de la cabine.

Advantageously, the housing comprises:

• means for measuring, on a phase wire of the stator of the driving motor of the car, the voltage, the current, the phase shift between voltage and current, and the frequency of the stator rotating field,
• means for calculating the rotor slip, the rotor speed, the speed of the car, and the position of the car relative to a reference level, and
• multiplexing / demultiplexing means for parallel communication with the control cabinet and serial communication with the cabin button box.

• la figure 1 représente un schéma du principe de fonctionnement du procédé selon l'invention ;
• la figure 2 est un schéma d'un dispositif selon l'invention.

Other characteristics and advantages of the invention appear from the following description given with reference to the appended drawings in which:

• the figure 1 represents a diagram of the operating principle of the method according to the invention;
• the figure 2 is a diagram of a device according to the invention.

On the figure 1 , the control cabinet 1 controls the drive motor 2 of the elevator car.

The motor 2 is a conventional asynchronous motor, whose stator is fed with three-phase current. On one of the 3 phase wires, is arranged a ring 4 of ferrite to allow the measurement of the voltage, the current and the phase difference between current and voltage, and the frequency of the stator rotating field. The first calculation means 5 define at 8 the energy consumed by the motor, and at the frequency of the stator rotating field. The second calculation means 6 define at 9 the sliding of the rotor of the motor 2. The third calculation means 7 define at 11 the speed of the rotor. The fourth calculation means 12 define the speed of the cabin. They receive at 13 an indication of the direction of movement of the cabin, uphill or downhill. They receive at 14 a synchronization signal at each passage of the cabin at the reference level corresponding preferably to level 0. On the basis of this information, they define in 15 the position of the cabin relative to the reference level, corresponding to the absolute position of the cabin. During a learning phase symbolized at 16, the distances between the reference level and the positions of the cabin, corresponding to the levels of the different stages, are stored. Visual and audio information delivered to booth 18 is available at 17.

The direction of movement of the cabin corresponds to the direction of rotation of the rotor, that is to say to the direction of rotation of the rotating field of the stator, which is determined by measuring the voltage on the three phases of the stator.

The method for determining the position of an elevator car according to the invention takes place as follows, the measuring and calculation means being active. First, rotor slip is calculated during a calibration phase. The cabin is sent from the reference level to the highest level and then from the highest level to the reference level.

During these two trips for which the distances traveled by the cab are identical, the mechanical loads of the engine are different. Indeed, uphill, the counterweight ensures the drive of the cabin, and downhill, the motor ensures the displacement.

Between the descent and the climb, the difference in the number of revolutions of the stator rotating field of the motor, with respect to the difference of energy supplied to the motor corresponds to the ratio R = slip / energy, which is a characteristic characteristic preserved.

Then, during a learning phase, the cab is sent from the reference level to the highest level with stop at all intermediate levels, and the positions of the stages according to the current, the slip and the direction of travel. of the cabin, are stored.

In normal operation, on a single phase wire of the stator and by means of the ferrite ring 4, the current, the voltage, the phase difference between current and voltage, and the frequency of the stator rotating field are measured. The first calculation means 5 deduce on the one hand in 8, the energy supplied to the engine 2, or consumed by the engine 2, which is equivalent, on the other hand in 10, the frequency of the stator rotating field of the engine . The second calculation means 6 apply to the calculated energy available at 8 the ratio R to deduce the slip available at 9. The third calculation means 7, from the slip and the frequency of the stator rotating field, define the speed rotation of the rotor. The fourth calculation means 12 convert the speed of rotation of the rotor into a linear speed of movement of the cabin driven by the rotor. Depending on the travel time, they define the distance traveled by the cabin, and from the reference level 0, they define the absolute position of the cabin. In comparison with the height positions of the different floors, the announcement of the information relating to the floors, and in particular to the floor of arrival, are delivered in the cabin, from the absolute position of the cabin, and without reference to a floor signal obtained by sensor or by contact in the elevator shaft.

In other words, the measurement of the electrical quantities at the stator makes it possible to determine a theoretical distance traveled as a function of the number of revolutions made by the stator field of the motor, and by calculating the sliding of the rotor with respect to the rotating field as a function of the power supplied to the engine, it is precisely determined the distance traveled by the cabin.

On the figure 2 , the device for implementing the method of determining the position of the elevator car is schematized. In the cabin 18, the button box 19 is equipped with advertising means 20, visual and sound, and multiplexing / demultiplexing means 21. In the vicinity of the control cabinet 1, the connecting box 22 contains on the one hand all the measurement and calculation means necessary for implementing the method for determining the position of the elevator car, and secondly multiplexing / demultiplexing means enabling it to communicate parallel with the control cabinet 1 , and serial communication with the cab via line 23.

Thus, on the one hand the control cabinet is not changed, on the other hand the wiring between the control cabinet and the cabin is reduced to a single line with two conductors. Only the button box must be replaced when the lift is brought into compliance with the appropriate safety rules for users with a disability.

• La détermination de la position de la cabine sans capteur dans la gaine d'ascenseur ;
• La gestion de l'annonce vocale en cabine correspondant à l'identification de l'étage avant arrivée à l'étage ;
• La gestion des afficheurs de palier, et notamment des flèches indiquant le sens de déplacement de la cabine ;
• Le renvoi vers l'armoire de manoeuvre des commandes d'envoi de la cabine ;
• Le renvoi vers l'armoire de manoeuvre des informations d'ouverture et de fermeture de la cabine.

The linkage housing 22 provides a number of functions including:

• Determining the position of the sensorless cab in the elevator shaft;
• The management of the voice announcement in the cabin corresponding to the identification of the floor before arrival to the floor;
• The management of the bearing displays, and in particular arrows indicating the direction of movement of the cabin;
• The return to the control cabinet of the orders of dispatch of the cabin;
• The reference to the control cabinet of the opening and closing information of the cabin.

The invention has been described with reference to an exemplary embodiment given by way of illustration and not limitation.

Claims (11)

1. A method for determining the position of an elevator car driven by an asynchronous motor, characterized in that, for movement of the car:

   - at the stator of the motor, the energy consumed by the motor and the number of revolutions of the stator rotating field is measured;

   - the distance traveled by the car is computed from the slipping of the rotor of the motor and the measurements of the energy consumed by the motor and the number of revolutions of the rotating field, and

   - the position of the car is determined relative to a reference level.
2. The method according to claim 1, characterized in that the measurements of the energy consumed by the motor and the number of revolutions of the stator rotating field are done on a phase conductor of the stator.
3. The method according to claim 2, characterized in that the measurements on a phase conductor of the stator are done using a ferrite ring.
4. The method according to claim 2, characterized in that the measurement of the energy consumed by the motor comprises measurements of the voltage, current and voltage-current phase shift.
5. The method according to claim 1, characterized in that the slipping of the rotor is determined during a calibration phase comprising a rise of the car from a reference level to the highest level, and a lowering of the car from the highest level to the reference level, measuring, between the lowering and the rising, the differences in number of revolutions of the rotating field and energy consumed by the motor, to deduce a ratio of the slipping to the consumed energy.
6. The method according to claim 1, characterized in that during a learning phase, the distances between the car and the reference level, corresponding to the height positions of the floors, are stored.
7. The method according to claim 1, characterized in that in order to compute the distance traveled by the car, from the number of revolutions of the rotating field and the slipping, the speed of rotation of the rotor is computed, the movement speed of the car and the distance traveled by the car being deduced therefrom.
8. The method according to claim 1, characterized in that each time the car passes by the reference level, a synchronization is done in order to determine the position of the car.
9. A use of the method according to one of claims 1 to 8 to trigger floor announcements.
10. A device for implementing the method according to one of the preceding claims, characterized in that it includes:

    - in the elevator car (18), a control box (19) equipped with multiplexing/demultiplexing means (21) and visual and audio announcement means (20);

    - near the switch cabinet (1), a connecting unit (22) between the switch cabinet (1) and the elevator car (18); and

    - between the control box (19) and the connecting unit (22), a serial communication line (23).
11. The device according to claim 10, characterized in that the connecting unit (22) includes:

    - means for measuring, on a phase conductor (3) of the stator of the motor (2) driving the car, the voltage, current, voltage-current phase shift, and frequency of the stator rotating field,

    - means for computing the slipping of the rotor, the speed of the rotor, the speed of the car, and the position of the car relative to a reference level, and

    - multiplexing/demultiplexing means to provide parallel communication with the switch cabinet (1) and serial communication with the control box (19) of the car (18).

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