JPS6147794B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a load pattern correction device for further correcting a load pattern generation device for compensating for an unbalanced load between an in-car load and a counterweight in an elevator.

FIG. 1 shows an example of a conventional elevator control system. In the figure, 1 is a reference pattern generator that generates a reference speed pattern signal for the elevator, 2 is a relay contact for switching with the landing pattern, and 3 is an addition/subtraction between the reference signal output from the reference pattern generator 1 and the feedback signal. Point 4 is an amplifier that amplifies the output of addition/subtraction point 3. 5 is a field winding of a generator which will be described later, 6 is a DC generator directly connected to an induction motor (not shown) constituting a Ward Leonard, and 7 is a separately excited hoisting motor which is excited with a substantially constant current and which will be described later. A field winding, 8 is a DC motor for a hoisting machine, and 9 is an interpol winding used for taking out a current anti-hunt signal. 11 is a counterweight, and 12 is an elevator car connected to the counterweight 11 by a rope via a sheep 10 directly connected to the shaft of the hoist 8. 13 is a landing pattern generator that generates a reference pattern signal near landing based on the expected landing position; 14 is installed under the floor of the car 12 and inserted between the floating car floor and the car frame. A load detector 15 detects the load inside the car 12 by detecting the displacement of the anti-vibration rubber, and 15 detects the terminal voltage from a pilot brush provided in the commutator of the hoisting machine and applies voltage negative feedback and voltage anti-hunt. 16 is a circuit that applies current anti-hunt using the current signal taken out from both ends of the interpol 9; 17 is a landing signal that synchronously rectifies the signal obtained by the landing pattern generator 13 and uses it as a reference signal at the time of landing. The generator circuit 18 is a load pattern generator that stores the signal from the load detector 14 just before the vehicle is running, and generates a signal that changes depending on the load and adds it to the reference signal as a constant signal while the vehicle is running, as shown in FIG. be.

Next, FIG. 2 is a characteristic diagram showing the relationship between the speed pattern of the elevator and the armature current of the hoisting motor 8 in the case of full load rising operation. In FIG. 2, 21 is the elevator speed pattern that is the output of the reference pattern generator 1, 22 is the load pattern that is the output of the load pattern generator 18 and is necessary to flow an armature current that balances the unbalanced load, and 23 is the elevator speed pattern that is the output of the reference pattern generator 1. This is a reference signal obtained by combining the speed pattern 21 and the load pattern 22, and by this reference signal 23, 2
As shown in 4, the armature current flows and the influence of the unbalanced load is canceled, and the elevator can start without hanging down.
Moreover, it is possible to land on the floor with high precision.

However, when comparing the landing pattern signal (output of the landing signal generation circuit 17) and the load pattern signal (output of the load pattern generation device 18) when the speed becomes extremely low near the landing of the elevator, for example, According to the circuit shown in Figure 1, the load pattern signal is about 10 times stronger. In order to reduce the dependence on this load pattern, it is sufficient to sufficiently increase the amplification factor of the amplifier 4, but when using a magnetic amplifier as an amplifier, there is a limit in terms of responsiveness, etc., and it is difficult to improve it. It is. Also, in order to reduce the dependence on the load pattern, it would be better to create a current minor loop so that the load pattern and current are balanced.
This is generally difficult to achieve when using magnetic amplifiers. In this way, it is difficult to reduce the dependence on the load pattern, and the error occurs immediately and when the brake is released at the start, the load torque of the motor (unbalanced torque) and the torque generated by the armature current are balanced. This has the drawback of causing misalignment, resulting in drop-off and landing errors. The causes of this error are: (1) Changes over time in the vibration isolating rubber for displacement detection due to the load of the weighing device under the car floor (rubber crushing, etc.), (2) Changes over time in the linear homer of the conversion section of the weighing device, (3) ) The main cause is temperature drift in the linear homer of the weighing device, etc. In most cases, this is a phenomenon in which the zero point of the load pattern is out of order, which causes a shock when the elevator starts up, an unstable landing position of the elevator, and a deterioration in landing accuracy.

Therefore, the present invention provides a load pattern correction device that can always correct the balanced load to the correct balance even if the vibration isolating rubber under the car floor changes over time or temperature drift occurs in the differential transformer, power transformer, load pattern generator, etc. The purpose is to provide.

The main feature of the present invention is that when an elevator car lands on the floor, the car is controlled by the landing pattern and is balanced against the unbalanced torque due to the weight difference between the car and the counterweight, and the load pattern and the balancing current are generated when the car is stationary. The detected value is regarded as a deviation (deviation) from the correct value of the load pattern, the deviation value is stored in memory again, and the deviation value is added to the load pattern as a correction signal to correct the load pattern. The main point is that it is corrected to an accurate pattern.

That is, in order to keep the landing accuracy of the elevator stable, comfortable, and highly accurate when the car lands on the floor, the pattern of the landing signal generation circuit 17 is adjusted linearly with respect to the landing error as shown in FIG. generate voltage,
When the car 12 reaches near the expected landing position and its speed becomes extremely low, the relay contact 2 is switched to the landing signal generation circuit 17 side, and the electric motor is activated by a pattern voltage proportional to the landing error from the expected landing position. Conventionally, control for accurately stopping the car at the expected landing position by adjusting the slave current (landing control) has been commonly performed. In addition, in the case of a gearless elevator, in order to ensure a comfortable ride and a highly accurate landing, it is recommended to apply the brakes approximately 0.6 to 1 [sec] after the elevator has balanced and stopped using the above-mentioned landing control. It's normal. During the time when the car is at rest due to such landing control, an armature current that perfectly balances the unbalanced torque flows through the motor 8. This is because when there is no balance, the car moves and the landing error changes, so the landing pattern output changes as shown in FIG. 8 and always reaches an equilibrium point. At this time, the load pattern output and the amount of current feedback should be exactly balanced and the landing error should be zero, but if there is a deviation in the load pattern, the motor torque due to the load pattern will be an unbalanced torque. A landing error occurs due to the inability to balance, and the deviation is compensated for by the landing pattern shown in Figure 8, which is proportional to this error and is output, and equilibrium/rest is reached at a certain landing error position. Become. Therefore, the present invention detects the difference between the amount of current feedback and the load pattern when the output torque of the motor 8 and the unbalanced torque are balanced and the car 12 is in a stationary state through control based on such a landing pattern. By treating this difference as a shift in the load pattern and writing it into memory, and using that memory to correct the load pattern in the direction without any shift in subsequent control, accurate loading can be achieved even if the load pattern changes over time. This makes it possible to prevent the suspension from falling when starting.

The present invention will be described in detail below based on illustrated embodiments. FIG. 3 is a block diagram showing a speed control system in one embodiment of the present invention, and the same parts as in FIG. In Figure 3, 1
Reference numeral 8 denotes the load pattern generation device described above, 19 a load pattern correction device according to the present invention, and 20 a memory rewriting command signal.

FIG. 4 is a circuit diagram showing details of the load pattern correction device 19. In Figure 4, MT is a relay that turns ON when it detects that the elevator has decelerated and entered the landing zone and approached the landing level (for example, within ±30 [mm]), and the car starts. When the door is completely closed, the normally closed contact LUDb of the relay LUD (not shown) turns OFF from the positive power supply PC. At that time, the contact
A certain time constant (for example, 0.5
[sec]. Afterwards, relay MT is turned off. Relay MT
When OFF, the normally closed contact MTb of relay MT closes, and therefore the positive power supply PC - contact
MTb - Contact BKa - Resistance 2R - Relay RY ₁ - Negative potential
Current flows through the NC circuit and rewriting relay RY ₁ is energized. Here, BKa is a normally open contact of a contactor BK (not shown) for controlling the electromagnetic brake of the elevator, and when this contactor BK turns ON, the brake coil is excited and the brake is released. Conversely, when BK is turned OFF, the brake coil is deenergized, so the brake is activated by the spring force.

IC ₁ is an operational amplifier that constitutes an adder circuit, and this adder circuit receives the output of the load pattern generator 18.
V ₁₂ and a signal V _I1 proportional to the main circuit current are input. It is necessary to consider (including the configuration of the current anti-hunt circuit 16) so that the input signal V _I1 has the opposite polarity to V _I2 . In addition, when the input resistances R1 and R2 are correct, the values of the load pattern 22 are correct (this can be checked as the load pattern output that generates a torque exactly equivalent to the unbalanced torque when _RY2 in Fig. 4 is OFF). Select so that the IC ₁ output becomes zero when the adjustment resistor VR ₁ is set to zero.
Next, the adjustment resistor VR ₁ is adjusted to set the output AI of the operational amplifier IC ₁ to, for example, 7.5 [V].
This is because the input characteristics of the AD converter generally handles only positive input, and is not an essential problem. C ₁ inserted into the feedback circuit of IC ₁ detects the vibration component of the current and the load pattern 2 when the car lands on the floor.
This is a smoothing capacitor to eliminate the influence of fluctuations in The ADC is an 8-bit AD converter that converts the output AI of the operational amplifier IC ₁ into a digital quantity. As shown in FIG. 6, this ADC outputs a DATA READY signal that goes high every few milliseconds, and outputs a correct signal during the high level.
IC ₅ is a monostable multivibrator, and when relay contact RY1a ₁ is open, it is a reset terminal.
CD has become low level and is preventing memory rewriting of 8-bit latch IC4. When the contact _RY1a1 closes, the reset terminal CD becomes high level, and only during the time constant determined by the resistor R5 and capacitor C2 when the input terminal A inverts from "L" to "H" at the rising edge of the DATA READY signal. It becomes a high level and writes the ADC output state and the deviation between the load pattern and the actual balance current during that time, and after a few milliseconds, it becomes a low level and is memorized. relay
While RY1 is ON, it can be rewritten and memorized every few milliseconds. The output of latch IC4 is D
- Input to A converter DAC, output of DAC is terminal
Issued by AO.

IC2 is an output inverting amplifier, VR2 is a variable resistor for fine adjustment of the gain of IC2, and A-D converter ADC and D-A
This is for correcting the conversion error of the converter DAC. IC3 outputs load correction to load pattern 22 (output of IC2)
This is an operational amplifier for adding. When the power is turned on, RY2 receives the first rewrite signal and relay RY
There is no guarantee that the output state of latch IC4 is correct until RY1 turns ON.
This is a relay to control IC2 so that it does not output until it turns ON. This relay RY
Once relay RY1 is turned on, relay 2 holds itself and remains energized until the next time the power is turned off. Due to this self-holding, there is no correction until rewriting when the power is turned on, so although the error may become slightly larger, danger can be prevented.

FIG. 7 shows an example of a correction value display circuit. That is, digital outputs BIT1 to BIT8 of latch IC4 in FIG. 4 are buffer converters, respectively.
Input to IC11~IC18 and output BIT1~BIT8
is current amplified, and emitter follower circuits Q1 to Q8
given to the gate. Emitsuta follower circuit Q1
~Q8 are connected to light emitting diodes LD1 to LD8 via resistors R11 to R18. This circuit shows each digit of the binary system in the order of LD1 to LD8 if the error is zero, and sets it so that it becomes "10000000". 10111001" lights up, so you can set the upper and lower limits of the error, and when the value exceeds that value, you can easily notify that the load pattern needs to be readjusted and corrected. . This light emitting diode display can provide accurate information in terms of maintenance and optimize maintenance periods.

Note that the correction device of the present invention is applicable not only to the above-mentioned control system but also to a control system having a current minor loop. In addition, the means for detecting the armature current of the motor 8 is not limited to detection using the Interpol 9, but it is also possible to use other current shunts, Hall elements, etc., and the detection signal can be sent to the main circuit via an insulating unit, etc. It is also possible to take it out by insulating it with direct current.

As described above, according to the present invention, the following effects are achieved.

(1) Even if the load pattern changes over time, the output is automatically corrected, resulting in high landing accuracy.
Moreover, it is possible to provide a stable elevator with a comfortable ride at all times.

(2) Since it is corrected every time it lands on the floor, it is less affected by the creep phenomenon of the anti-vibration rubber under the car floor, which takes several minutes.

(3) The value when the torque generated by the hoist actually balances with the unbalanced load is converted into the signal level of the load pattern, and the deviation is memorized, so correction is reliable.

[Brief explanation of the drawing]

Fig. 1 is a block diagram showing a conventional elevator control system, Fig. 2 is a characteristic diagram showing the relationship between the elevator speed pattern and current, and Fig. 3 is a diagram showing the load pattern correction device according to the present invention in the elevator control system. 4 is a circuit diagram showing an embodiment of the elevator load pattern correction device according to the present invention; FIG. 5 is a diagram showing the characteristics of the load pattern generator 18 in FIG. 4; 6 is a diagram showing signal waveforms of various parts related to the operation of the monostable multivibrator IC5 for storage in FIG. 4, FIG. 7 is a diagram showing each embodiment of the display circuit, and FIG. FIG. 1... Reference pattern generator, 6... DC generator,
7... DC motor for hoisting, 10... Sheep, 11... Counterweight, 12... Elevator car, 13... Landing pattern generator, 14... Load detector, 17... Landing signal generation circuit, 18... Load pattern generator ,
19... Load pattern correction device, ADC... Analog-digital converter, DAC... Digital-analog converter, IC4... Latch circuit, IC5... Monostable multivibrator, RY1... Rewriting relay,
RY2...Relay for correction.

Claims (1)

[Claims] 1. A load pattern generator that detects the load in the elevator car and generates a load pattern signal corresponding to the unbalanced load with the counterweight, and a reference pattern that generates a reference speed pattern signal for raising and lowering the car. and a landing signal generating device that emits a landing pattern signal corresponding to a landing error when the car lands on the floor, and by passing a current corresponding to the load pattern signal to a DC motor that drives the car up and down. While balancing the unbalanced load,
When the car is raised or lowered, the elevator speed of the car is controlled by adjusting the current based on the reference speed pattern signal, and when the car lands on the floor, the elevator speed of the car is adjusted by adjusting the current based on the landing pattern signal. In an elevator control device that adjusts the rest position of the electric motor, when the car is in a resting state under the unbalanced load and the mechanical brake is not yet activated by the control at the time of landing based on the landing pattern signal, the electric motor a storage device that stores a deviation signal between a signal proportional to the value of the current flowing through the load pattern signal and the load pattern signal, and using the deviation signal stored in the storage device,
A load pattern correction device for an elevator, comprising: a correction circuit that corrects the load pattern signal in subsequent control. 2. The storage device includes an AD converter that converts the deviation signal into a digital quantity, a latch circuit that stores the output of this DD converter, and a latch circuit that converts the output of this latch circuit into an analog quantity and stores the digital quantity. 2. The elevator load pattern correction device according to claim 1, further comprising a DA converter that outputs a signal used for correction to the correction circuit.