JPS6135111B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an elevator control device that corrects a car landing error.

In general, high-end elevators such as DC gearless elevators are generally used in large-scale buildings, and often have long lifting and descending strokes. When the lift distance is about 70m or more, even if the landing error is small when the elevator lands on the lower floors of the building where many passengers come and go, the hoisting machine and car in the elevator machine room will be affected by the coming and going of passengers. The hanging rope between the elevators expands and contracts, resulting in errors in the elevator's landing. In a building with about 60 floors, for example, even if the car returns to the first floor on the morning of work and opens the door with zero landing error, the rope will stretch 70 to 80 mm by the time the passengers have boarded the car. The floor of the terminal is lower than the first floor landing floor, creating a danger for passengers to trip.

To prevent this, we use a rope expansion/contraction correction device called a wire stretch return, which detects when the landing error due to rope stretching exceeds a certain amount, and slowly moves the door in a direction to reduce the error while the door is open. It has been common practice to move the car to re-align the floors.

On the other hand, as a speed pattern, when accelerating, the voltage is advanced by a timer, and when decelerating, the voltage is lowered according to the remaining distance to the expected landing floor in order to increase landing accuracy.The step pattern shown in Figure 1 is passed through a primary delay circuit. It has been commonly used because it is cheap and easy to obtain in a smoothed form. When a step pattern is smoothed by a delay circuit, if the response speed of the control system is fast, current ripples are likely to occur at the transition points of the step pattern shown in FIG. 1, resulting in poor riding comfort. In order to maintain system stability, the amount of current disturbance prevention is made much larger than necessary to delay the current response and smooth the ride.

When a rope expansion/contraction correction operation is performed in such a system, the following problems occur because the current response is slow.

(1) It takes, for example, about 2 seconds to settle the balance current. Therefore, when the elevator brake has already been released and the balancing current has been cut off, it will be dangerous if the brake is not opened after waiting for more than this time after the balancing current starts flowing, and it will take time before the rope expansion/contraction correction can be performed. Not in time.

(2) The brake is loosened during the rope expansion/contraction correction operation, but if a person suddenly gets on and off, or a cart loaded with luggage comes in and out, the required balance torque will change suddenly, but the electric current cannot follow it, so the motor The car suddenly moves significantly due to insufficient torque. Experiments have shown that if 3 or 4 people step out at the same time, the basket may jump up about 200 mm, which is dangerous.

(3) Because the response of the control is slow, the time limit may be completed and the operation may be terminated before the landing level is sufficiently improved.

These problems may cause practical problems, and urgent improvements have been desired.

SUMMARY OF THE INVENTION An object of the present invention is to provide an elevator control device that eliminates the above-mentioned drawbacks and allows safe level adjustment by making the current response speed during rope expansion/contraction correction faster than during running.

The present invention will be explained below based on the illustrated embodiments. FIG. 2 shows a block diagram of an embodiment of the present invention. 1 in the figure is the DC generator armature of the motor generator.
Reference numeral 2 is a DC motor armature of a hoisting machine, and 3 is a separately excited field winding for the DC motor, through which a substantially constant current is passed. 4 is its commutator winding, 5 is the DC motor armature 2
The sheave 6 is a rope that is directly connected to the cage 7. A cage 7 is connected to one end of the rope, and a counterweight 8 is connected to the other end. 9 is a step pattern generation circuit; 10 is a delay circuit such as a first-order delay; 11 is a landing pattern generation circuit; 12a and 12b are turned off when the car 7 approaches about 150 mm before the landing level during deceleration; After the car 7 has stopped, there is a call to be answered next, and when the door is completely closed, the a and b contacts of a relay 12 (not shown) are turned on, 13 is an addition/subtraction section, 14 is an amplifier, 1
5 is a DC generator field winding, 16 is a pilot brush for detecting the armature voltage of the hoisting motor, 17 is a proportional differential circuit for voltage return and voltage disturbance prevention, 18, 1
9 are both differentiating circuits for preventing current disturbance, 18R, 1
9R is a resistor, 18C, 19C are capacitors, 2
0a ₁ , 20a ₂ , 20a ₃ , and 20b are a contacts of a rope expansion/contraction correction command relay 20, which will be described later. Further, 21 is provided under the floor of the car 7, and this car 7
A load measuring device 22, such as a linear homer, is used to generate armature torque using the output of the load measuring device 21 to balance the differential torque between the car 7 and the counterweight 8. This is a load pattern generator. 23a ₁ and 23a ₂ are a contacts of a travel command relay 23, which will be described later.

Next, FIG. 3 shows a circuit diagram of a speed pattern command and a brake operation command at the time of rope expansion/contraction correction. In the figure,
PC is a positive power supply bus, NC is a negative power supply bus, and WSLa is a contact a of a proximity relay (not shown) that is energized when the landing error is larger than, for example, 10 mm and opened when it is smaller than, for example, 5 mm. The above-mentioned output is produced using an iron detection plate fixed to the sensor. Furthermore, INSb is the b contact of an inspection relay (not shown) that is turned on during inspection, and 23b is turned on while driving and landing on the floor (also during rope expansion/contraction correction operation).
B contact 24a of relay 23 (not shown) to be turned off
is an a contact of a door opening relay 24 (not shown) which is turned on when the door is fully opened, WSR is a rope expansion/contraction correction detection relay, and WSRa ₁ and WSRa ₂ are its a contacts. WBK is an on-delay electromagnetic brake release command timer that is turned on when the wire stretches back and excites the electromagnetic brake for controlling the hoisting machine (not shown); 20 is a rope expansion/contraction correction command relay; R and C are off-day relays for the rope expansion/contraction correction command relay 20. These are time-limiting resistors and capacitors.

In FIG. 2, when the elevator departs from a certain floor, when the door closes close to fully closed, the relay 12 is turned on by a known circuit (not shown), and the a contact 12a is turned on.
closes and the velocity pattern becomes valid. At this time, since the a contact 24a is open in Fig. 3, the relay
Both WSR and 20 are off, and the a contact 2 in Figure 2
The contact points 0a ₁ to 20a ₃ and the b contact 20b are as shown in the figure. The stepped pattern generator 9 generates pattern voltages in the illustrated stepwise manner based on time during acceleration and based on distance during deceleration, and is smoothed by the delay circuit 10 as shown in the curve shown in FIG. Since the relay 12 is on, the output of the delay circuit 10 is the adder/subtractor 1
Added to 3. The output signal Vf of the proportional differentiation circuit 17 is added to this adder/subtractor 13 as a negative feedback signal, and the load pattern W generated by the load pattern generator 22 is added as a + signal (in the direction of canceling the unbalanced torque). , differentiation circuit 18,
The output signal If of No. 19 becomes a - signal. These differences are amplified by an amplifier 14 and applied to the DC generator field winding 15, and the generator generated voltage generated across the armature 1 is applied to the DC motor armature 2 of the hoisting machine to generate torque. The car 7 is then accelerated and driven according to the pattern shown in FIG. As the car 7 approaches the floor where the next call is to be stopped, it decelerates by known means and when it approaches about 150 mm before the landing level, the relay 12 is turned off and the landing pattern generation circuit 11 is turned off.
The landing pattern shown by the dotted line in Figure 1 (this is, for example, a type of differential transformer installed on the car 7) is used to determine the landing position of the hoistway between the excitation winding and the detection winding. (This is a well-known method that uses vanes made of specially shaped iron plates attached nearby.) This pattern becomes smaller continuously and smoothly as it approaches the landing point, and if it overruns, it becomes reverse polarity and serves to return the car 7 to the landing level. As shown in Fig. 1, the output of the delay circuit 10 essentially waves, and in particular, when trying to produce a distance-based effect, the time constant of the delay circuit 10 cannot be made that large, and the response speed of the control system is fast. The current responds faithfully and the current waves, making it feel uncomfortable. Therefore, in this embodiment, since the rope expansion/contraction correction command relay 20 is off as described above, the differentiating circuit 19 is connected in parallel to the differentiating circuit 18, and the time constant value required to maintain stability (for example, 0.1 to 0.2 seconds) is used. The differentiating circuit 18 is set to a significantly larger time constant value (for example, 2 to 4 times the value of the time constant) to reduce ripples in the current.
and 19 resistance values and capacitance values of the capacitor are selected.

Next, let us consider a case where the empty car 7 stops at the lower floor of a building, the door opens, and passengers board one after another. E in Figure 4 shows the landing error; at t = 0, the door opens and the passenger begins to board, and the brake is already applied, but the lobe 6 begins to stretch due to the weight of the passenger, and at t = t ₁ , the landing error occurs. is a given value E ₁ (e.g. 10
mm), this is the a contact point in Figure 3.
WSLa is closed, and since it is not during inspection, B contact INSb is also closed, and since it is stopped, B contact 23b is also closed, and since the door is fully open, A contact 24a is also closed, so the rope expansion/contraction detection relay WSR is turned on. Then, the rope expansion/contraction correction command relay 20 in FIG. 3 is turned on, disconnecting the differential circuit 19 in FIG. 2, reconnecting the load pattern and the landing pattern, and causing a current to balance the unbalanced load to flow in advance before opening the brake. Since the electromagnetic brake release command timer WBK in Fig. 3 is set to turn on after 0.5 seconds, for example, the exciting current I _B flows to the electromagnetic brake (not shown) as shown in Fig. 4, and the level error of car 7 is reduced. Move slowly in the direction.
At this time, the differentiating circuit 19 is disconnected by the rope expansion/contraction correction command connector 20. Since the implantation pattern is a smooth pattern, the remaining differential circuit 18
The constant should be selected as small as possible within the range that maintains the stability of the system, so the response speed is fast, and even if passengers get on the train one after another and the load torque suddenly changes, it can easily be followed and there is no danger. When the landing error returns to a predetermined value (for example, ±5 mm), the a contact WSLa turns off, and the rope expansion/contraction correction detection relay WSR and the electromagnetic brake release command timer WBK turn off to release the brake, but the rope expansion/contraction correction command relay 20 It turns off after a delay of the time constant of resistor R and capacitor C. This is because the speed pattern is turned off after applying the brakes, and this is to prevent the car 7 from moving suddenly if the pattern disappears just before the brakes are applied.

As detailed above, according to the present invention, (1) a smooth ride can be obtained even if an inexpensive stepped pattern is used, and a sufficiently fast response speed can be obtained during the rope expansion/contraction correction operation when driving with the door open; It is safe.

(2) Since the current response is not faster than necessary during high-speed driving, there are great practical effects such as safety even if noise is added to the pattern.

In the above description, a relay contact is used to turn on and off the differential circuit, but it is of course possible to use an impedance element such as a transistor to continuously switch the differential circuit.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing an elevator speed pattern waveform, FIG. 2 is a block diagram showing an embodiment of the present invention, FIG. 3 is a control circuit diagram of FIG. 2, and FIG.
It is a figure which shows the time chart for demonstrating the operation|movement of a figure. 2... DC motor armature, 5... Sheave, 7... Car, 18, 19... Differential circuit, 20... Rope expansion/contraction correction command relay, 20a ₁ , 20b... Contact.

Claims (1)

[Claims] 1 A rope-suspended elevator in which the car is driven by a DC motor, in which a pattern value is obtained by smoothing the output of a step-like pattern generation circuit through a delay circuit during running, and a pattern from the landing pattern generation circuit when landing on the floor. The value and the output of the load pattern generator are connected and added to an adder/subtractor during running, and the return voltage of the DC motor is negatively returned to the adder/subtractor via a return loop, and the car is placed on the floor. In the elevator control device, the landing level is corrected by connecting the output of the landing pattern generating circuit and the output of the load pattern generating device to an adder/subtractor using a rope expansion/contraction correction command device. Two differentiating circuits for preventing disturbances are provided in parallel and connected to the adder/subtractor in a negative feedback loop, and one of these two differentiating circuits is opened by the operation of the rope expansion/contraction correction command device. An elevator control device characterized by: