JPS6153983B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in an elevator control device that uses pulses emitted as the car runs to generate car position information and thereby control the elevator.

To control the operation of an elevator, it is necessary to know where the elevator car is currently located in the hoistway. In recent years, as a method of detecting the car position, a method that counts pulses emitted in synchronization with the travel distance of the car has been widely adopted because it has the following advantages.

It has a better space factor than the conventional mechanical type that uses floor selectors and limit switches.

High accuracy.

Easy to maintain, inspect, and adjust.

This is a signal suitable for microcomputers, which have become increasingly used in elevator control in recent years.

Next, a crane-type elevator, which is the majority of current elevators, is shown in FIG. 1 and explained.
In FIG. 1, 1 is an elevator car (hereinafter simply referred to as car 1), and 2 is a counterweight (hereinafter simply referred to as weight 2). 3 is a main rope connecting the car 1 and the weight 2. 4 is an electric motor that drives the elevator; 5 is a sheave connected to the electric motor directly or via a reduction gear; on which the main rope 3 is hung. 6 is a tail cord that transmits signals between the car 1 and a control panel (not shown). 7 is a relay terminal block, 8 is a signal line, 9 is a car load detection device that detects the load inside the car 1, and 10 is a compen rope (or chain) that compensates for unbalance of the suspension caused by differences in car position. .

Next, a method of compensating for the unbalanced load of the elevator in such a configuration will be explained. first,
Unbalanced torque due to differences in loading conditions in the car is controlled by the output signal of the car load detection device 9 so that the electric motor 4 generates torque corresponding to the unbalanced torque. In addition, unbalanced torque that occurs due to changes in the conditions of the tail cord 6 and main rope 3 depending on the position of the car 1 is caused by the compensation rope 10.
will be compensated by. This compen rope 10 is
Ideally, it should be selected according to the formula below.

W ₁₀ = W ₃ − _{W 6} /4 ………(1) Here, W ₁₀ , W ₃ , W ₆ are compen ropes 10,
This is the weight for each unit length of the main rope 3 and tail cord 6.

However, the weight of the main rope 3 and tail cord 6
W ₃ and W ₆ vary depending on the specifications of the elevator, and on the other hand, the compen rope 1 according to equation (1)
0 requires very many types of compen ropes 10. For elevator manufacturers, there are many types of compen ropes10.
It would be a huge burden and not realistic to have all of these in place. In reality, elevator manufacturers have several types of compen ropes 10 and select the one closest to formula (1) from among them. In this way, if the actual compensator rope 10 is not the ideal one shown by equation (1), an unbalanced torque (hereinafter referred to as unbalanced torque X) that varies depending on the position of the car 1 is generated. This unbalanced torque
This can cause shocks such as "dropping" or "lifting" when the elevator starts, and can impair landing accuracy.

The unbalanced torque X changes depending on the car position, but the weight of the compen rope 10
If there is not a big difference from the value in equation (1), the unbalanced torque (Explain Compenrope 10 so that The unbalanced torque X increases proportionally as the car changes from that position. The proportionality constant is the weight of a unit length of compen rope used.
The difference between W ₁₀ ′ and W ₁₀ in equation (1) is ΔW ₁₀ = W ₁₀ −W ₁₀ ′ (2). FIG. 2 is for explaining this, with the vertical axis representing the unbalanced torque X and the horizontal axis representing the car position, with D representing the lowest floor and U representing the highest floor. Figure 2 shows the case where ΔW ₁₀ > 0, but Δ
When W ₁₀ <0, the straight line has the opposite slope.

An object of the present invention is to solve the above-mentioned problems in an elevator control device that obtains highly accurate car position information using pulses emitted in synchronization with the travel distance of a car.

The present invention will be described below with reference to the drawings. FIG. 4 is a control block diagram of an elevator representing an embodiment of the present invention. In the figure, 11 is a speed reference generator, 12 is a speed generator connected to the electric motor 4, and its output 12a is input to a speed amplifier 13 as a speed feedback signal, after which the deviation from the speed reference 11a is calculated. The output of the speed amplifier 13 is a current reference, and the output 9a (intra-cage load compensation signal) of the in-car load detection device 9 and the output of an operational amplifier 22, that is, a compensation signal 22a, which will be described later, are added to the output of the current detector 18. The deviation from the current feedback signal 18a, which is the output, is taken and the signal is input to the current amplifier 14. The output of the current amplifier 14 is converted into a signal suitable for a power converter 16 and transmitted by a signal converter 15, such as a phase shift control device. The power conversion device 16 transmits the electric power of the power source 17 to the electric motor 4 based on the output signal of the signal conversion device 15, and generates torque. 19 to 27 constitute a device for compensating unbalanced torque; 1
9 is a pulse generator that generates pulses in synchronization with the travel distance of the elevator car, and this output 19
a is counted by the counter 20. The counter 20 counts up when the car is going up, and counts down when the car is going down, based on a signal not shown. Count value 20a of counter 20
This becomes a car position signal and is input to the digital-to-analog converter 21. The car position signal 21a converted into an analog quantity is amplified by the operational amplifier 22 and becomes a compensation signal 22a. 23 and 24 are volumes, 25 to 27 are resistors, and 28 is a DC power line.

Next, the effects of this invention configured as described above will be explained. FIG. 3 is for explaining this, and shows the elevator car position on the horizontal axis and the compensation signal 22a on the vertical axis. The slope in FIG. 3 is the gain adjustment volume 2 of the operational amplifier 22.
4, and the zero cross point can be adjusted using the bias adjustment volume 23. In this way, in this invention, since the amount of compensation corresponding to the unbalanced torque X shown in FIG. 2 can be added to the current reference, that is, the torque command, the unbalanced torque Variations will be compensated.

In the above-mentioned embodiment, the digital car position information was converted to an analog value, and a compensation signal was created using an amplifier, a resistor, and a volume. However, using a digital calculator such as a microcomputer,
It is also possible to create a suitable compensation signal by calculating digital car position information. In that case, if the speed control system is constructed in an analog manner as in the above embodiment, it is ultimately necessary to convert the compensation signal into an analog quantity using a D/A converter or the like. Furthermore, when the entire speed control system is processed entirely in digital quantities using a digital computer such as a microcomputer, the compensation amount of this invention is calculated and processed within the computer and is reflected in the control. .

If the compensation according to the present invention is added to the elevator control system, the unbalanced torque X that cannot be compensated for by the compensation rope caused by the difference in car position can be completely compensated for. Therefore, when starting with the brake released, no matter where the car position is,
It is possible to eliminate starting shocks such as "hanging down" and "lifting up". Furthermore, landing errors caused by unbalanced torque X can also be eliminated.

[Brief explanation of the drawing]

Figure 1 is a diagram showing the configuration of a hanging type elevator.
Fig. 2 is a diagram showing the relationship between unbalanced torque due to inappropriate compensation rope and car position, and Fig. 3 is a diagram showing the relationship between compensation amount and car position to explain the effects of an embodiment of the present invention. , FIG. 4 is a block diagram showing an embodiment of the present invention. 1... Elevator car, 2... Counterweight, 3... Main rope, 4... Electric motor, 5... Sheave, 6... Tail cord, 7... Relay terminal block, 8
...Signal line, 9...Car load detection device, 10...
...Compenrope, 11...Speed reference generator,
13...Speed amplifier, 15...Signal conversion device, 1
6... Power converter, 17... Power supply, 19... Pulse generator, 22... Operational amplifier, 23, 24...
...Volume, 25-27...Resistor, 28...DC control power supply.

Claims (1)

[Claims] 1. A pulse generator that generates pulses in accordance with the travel distance of the car in a crane-type elevator in which an elevator car is balanced by a counterweight and the car and the counterweight are connected by a compensation rope. and a counter that counts the pulses output from this pulse generator, and the count value of this counter is inputted as car position information, and the unbalanced torque that cannot be compensated for by the compen rope caused by the car position at that time is calculated. 1. A control device for an elevator, comprising: arithmetic means for calculating a compensation signal, and for controlling an elevator by adding the compensation signal obtained by the arithmetic means to a torque command value of a control system of the elevator.