JP5255686B2 - Elevator control method - Google Patents

Description

Detailed description

  The present invention relates to a control method for controlling an elevator, particularly a variable speed, low weight, counterweightless elevator.

  In many residential applications, elevator cars and their hoisting mechanisms are (a) maximum planned traffic capacity or maximum number of people and (b) occasional movement of large furniture and / or wheelchair boarding. It is designed to be sized according to the size of the floor area that is possible. Large hydraulic motors and large fuses, especially for hydraulic and drum elevators that do not require or require counterweights, require bulky motors and large fuses, especially when building new elevators or retrofitting older elevators in older buildings Various problems arise in some cases. The inevitably swollen motor, large fuses and associated high current wires are also costly.

  However, most elevator operations typically carry less than 30% of the standard load. In approximately half the service, no passengers are in the car (see the virtual usage curve for elevators without counterweight in Figure 1).

  In traction sheave elevators, the counterweight is usually sized according to the weight of the car plus half the load. That is, energy equivalent to the weight of the car is saved when the car is operating in a full or unloaded condition. However, in a descent operation in a no-load state that is common in residential elevators, the hoisting mechanism requires maximum power in order to eliminate the net difference between the counterweight and the car in the no-load state. This causes extra energy consumption. U.S. Pat. No. 5,988,252 discloses a counterweight elevator system with a control system that measures the load capacity of the car, which measures the speed profile of the car based on the load capacity of the car To do. In a particular embodiment, the control system includes a load measuring device and uses the weight of the car to select one of two driving speed profiles: a normal driving speed profile and a reduced driving speed profile. The control system compares the measured load load with a preselected threshold. The threshold value is, for example, a numerical value obtained by adding the weight of the car and a value obtained by multiplying the percentage balance by the prescribed full load amount of the elevator system. If this threshold is exceeded, a deceleration operating speed profile is selected. In this way, a reduced degree of balance can be used. The selected percentage balance may be measured experimentally or estimated taking into account the building size, application and other operating characteristics. Thus, US Pat. No. 5,988,522 saves energy by making the counterweight less than half the load and reducing the speed of the hoist mechanism when the car is nearly full. This kind of weight-reduced counterweight system is practically difficult to implement.

  In many cases hydraulic, drum-driven, screw-driven or chain-driven elevators without counterweights are used, since these elevators offer several advantages, for example in terms of shaft space efficiency. In the conventional system for reducing the size of an elevator hoist motor without a counterweight, the motor is made smaller than usual in a specific element, and the number of activations per hour is limited. However, this still requires the motor to be about 70% of the total volume. This means that in a lift operation with no load, the motor consumes the weight of the car and the energy to carry almost the entire load.

  One of the objects of the present invention is to eliminate the drawbacks of the conventional system and to realize a system in which the elevator hoisting mechanism of an elevator without a counterweight is smaller than that of the conventional system. It is another object of the present invention to provide a traction sheave elevator that is economical in size and has no counterweight. Additional objectives are set forth herein either explicitly or implicitly. One of the objects of the present invention is to reduce the size of the machine and electric drive and possibly other components to sub-standards without significantly losing the size and capacity of the car.

  The invention is based on the idea that the variable speed hoisting mechanism is combined with an elevator without a counterweight where the car is light. The invention is defined in detail in the claims. Other embodiments of the invention feature elements that fall within the scope of the other claims. Some inventive embodiments are also described in the present specification. The contents of the present invention may also be defined differently from the scope of the claims. When considering the present invention particularly in light of sub-tasks explicitly or implicitly indicated, or in view of the advantages or types of advantages achieved, the content of the present invention may be comprised of several different inventions. In this case, some of the definitions included in the claims may be unnecessary from the viewpoint of other inventive concepts.

  (1) A hoisting motor and a driving device by a significant combination of a lightweight riding car, a load measuring device or other means for predicting the actual load of an elevator, and a variable speed hoist and an optional regenerative mechanism It is possible to significantly reduce the size and price of the battery, (2) a smaller fuse, and (3) a significant improvement in energy consumption. By providing an optional regenerative mechanism, the energy generated by the descent operation is saved and fed back to the power supply system. By using a variable speed hoisting mechanism in combination with an elevator without a counterweight, this mechanism can be adjusted for any load at each trip. On the other hand, conventional elevators, for example the elevator of US Pat. No. 5,988,252, have fixed counterweights and therefore use several fixed balancing systems for the majority of the operation. In other words, the motor uses energy to lift the counterweight in spite of the descent in the unloaded state.

It is a figure which shows the virtual utilization curve of the elevator without a counterweight. It is a figure which shows the traction sheave elevator without a counterweight.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, preferred embodiments of the invention will be described in detail with reference to the drawings.

  In FIG. 2, the elevator without a counterweight may be a traction sheave elevator without a counterweight. FIG. 2 shows a traction sheave elevator without a counterweight, which includes an elevator car 1, a hoisting device with a variable speed motor drive (for example, frequency converter 12 and AC motor 10), traction sheave 11, turning pulleys 4, 6 , 15 and a hoisting rope 3.

  The elevator shown in FIG. 2 is an elevator without a machine room, and the drive machine 10 is installed in the elevator shaft. The elevator shown is a traction sheave elevator with the machine on top. The route of the hoisting rope 3 of the elevator is as follows. One end of the rope is fixedly fixed to a support portion 16 provided on the upper portion of the shaft. The rope travels downward from this support, travels around the turning pulley 14 on the roof of the car, rises to the second turning pulley 15, and returns to the third turning pulley 13 on the roof of the car. From there, the rope further rises to the traction sheave 11 of the drive machine 10 and passes through the traction sheave along its ropeway. From the traction sheave 11, the rope 3 further descends toward the elevator car 1 moving along the car guide rail 2, and passes under the car through the fourth turning pulley 4 at the lower part of the guide rail 2. Thereafter, it rises again to the fifth turning pulley 5 at the lower part of the elevator car, descends again to the sixth turning pulley 6, and rises again toward the seventh turning pulley 7 at the lower part of the car. At the end of the turning pulley 7, the rope is fixed to the shaft floor 9 by springs 8 to the traction sheave and each turning pulley.

  The rope suspension acts almost at the center of the elevator car 1, and the rope pulley that supports the elevator car passes through the center of gravity of the elevator car 1 and is mounted substantially symmetrically with respect to the vertical center line.

  The drive machine 10 provided in the elevator shaft is preferably of a low profile, in other words, the machine is short in depth compared to its own width and / or height, or at least the elevator car and the elevator shaft. It is preferably thin enough to be attached between the wall. This machine may be installed in a different place, for example, a thin machine may be provided on a part or all of the virtual extension line between the elevator car and the shaft wall. A rope pulley position different from the present embodiment may be used for the traction sheave. Such a different position can be easily set by using the alternative pulley 11, and at this time, the alternative pulley transmits the traction force to another rope pulley serving as a traction sheave. In this case, the drive machine necessarily works with this further pulley. From the standpoint of machine sizing, the position of pulleys 11 and 4 is preferred as the pulley position for the highest rope speed. By increasing the number of pulleys and the rope extending to the upper and lower rigging of the elevator car, it is possible to increase the speed of the machine relative to the speed of the elevator car, and the motor torque requirements and size accordingly. It is also possible to reduce the size. For example, the traction sheave elevator according to the present invention can be implemented with a suspension ratio of 6: 1, 7: 1, 8: 1, 9: 1, 10: 1, or higher, in the elevator car upper and lower parts. . Enlarging the traction sheave and the hoisting rope can be improved by increasing the contact angle using the turning pulley. This allows the weight of the car and counterweight to be reduced and their size can also be reduced, increasing the potential for space savings in the elevator. As another method, or in addition to the above method, the weight of the car can be reduced with respect to the weight of the counterweight. By using one or more auxiliary turning pulleys, a contact angle exceeding 180 ° can be realized between the traction sheave and the hoisting rope. The equipment required for powering the motor that drives the traction sheave 11 and the equipment for elevator control may also be installed on the elevator shaft. It may be attached or partially or fully integrated with the drive machine 10.

  The drive machine may be geared or gearless. The preferred method is a gear machine. The drive machine may be fixed to an elevator shaft wall, ceiling, one or more guide rails, or other structures such as beams or frames.

  In the case of an elevator with the machine below, the machine may be attached to the bottom of the elevator shaft.

The system also includes a control unit that has load capacity measuring means in the car 1 and controls the operation of the elevator system. The total weight of the car is lighter than usual, especially lighter than elevators with similar counterweights. The speed driving unit is a variable speed driving unit. The variable speed hoisting mechanism is sized based on the output Pnom and the torque Tnom, and this is expressed by the following equation: Pnom = Mtotal * V (1)
Where V = speed, Mtotal = Mcar (mass of car) + A * maximum load, and Tnom is determined by Mtotal, acceleration, and the like.

  A is a coefficient determined by, for example, a reduction in the speed and acceleration of the motor, an increase in the idle time of the elevator, etc., has a value of 0 to 0.5, and is experimentally determined by a user survey.

A * When using a load instead of the maximum load,
1) reduce motor speed and acceleration accordingly,
2) Increase elevator idle time (for example, increase door opening and closing time)
As a result, the motor is cooled for a sufficiently long time to prevent the motor from being overloaded.

  Moreover, as long as it is within the allowable range of the waiting time of the occupants, the speed during operation when the elevator is not loaded may be greatly reduced.

  It goes without saying that the embodiments of the present invention are not limited to the above-described examples and can be modified within the scope of the claims of the present application. In particular, in the case of an elevator having a machine in the lower part, a drum elevator may be used, and the car is suspended by winding a hoisting rope around the drum of the hoisting machine. An elevator having a chain drive and a suspension mechanism is also suitable for use in the present invention. The load measuring device or other means of predicting the elevator load may be attached to an elevator car, rope, hoisting machine, other suitable elevator components, or drive motor, or other elevator The components may be used to measure the elevator car load or other load information.

Claims (1)

A control method for an elevator system without a counterweight, comprising an elevator car and a variable speed drive with an electric motor, wherein the load capacity of the elevator car is measured and the elevator system is controlled to physically control the system. / In the control method to reduce the electrical size,
The total mass of the elevator is defined by the equation Mtotal = Mcar (car weight) + A * maximum load (loading load reference value), where Mcar is the car weight, and A is the motor Is a factor having a value between 0 and 0.5, determined by one or more driving characteristics such as a reduction in speed and acceleration and an increase in the idle time of the elevator, the maximum load being the maximum load,
If the A * maximum load is set as the reference value of the load, and the load exceeds the reference value of the load, the speed corresponding to the load exceeding the A * maximum load is substituted for the A * maximum load. And acceleration are determined before operation,
Controlling the elevator,
Reduce the speed and / or acceleration of the motor,
Increase the idle time of the elevator,
Furthermore, the control method of the elevator system characterized by regenerating and using the energy at the time of descent service.

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