JPS6194980A - Controller for hydraulic elevator - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a device for controlling a hydraulic elevator that drives a hydraulic pump to cause a car to travel.

[Conventional technology]

One of the hydraulic control methods for hydraulic elevators is one using a flow control valve. When ascending, the electric motor is rotated at a constant rotation speed, this electric motor drives the hydraulic pump, and a fixed amount of oil is returned to the oil tank from the hydraulic pump. The speed of the car is controlled by adjusting the amount returned to the car with a flow control valve, and when descending, the car is lowered by its own weight, and this is adjusted with a flow control valve to control the speed of the car. In this method, excess oil is circulated during the ascent, and potential energy is consumed to heat the oil during the descent, resulting in large energy loss and a significant rise in oil temperature.

As an improvement on this t'L, for example, Japanese Patent Application Laid-Open No. 57-9
As shown in Japanese Patent No. 8477, an induction motor that drives a constant discharge oil pump is controlled by a control device made of semiconductor, and the voltage and frequency are adjusted over a wide range to control the rotational speed of the motor. It is suggested that something be done. That is, the discharge amount of the hydraulic pump is variably controlled by changing the rotational speed of the electric motor, which is inexpensive and highly reliable.

[Problem that the invention seeks to solve]

In the conventional hydraulic elevator control device as described above, due to leakage of the hydraulic pump, even if the hydraulic pump is rotated,
The car may not start immediately, ie, at time t, as shown in FIG. If an operation command is issued at t, the hydraulic pump will gradually accelerate until time t
1, the rotational speed n1 is reached. However, the car does not start due to leakage from the hydraulic pump.5 When the rotational speed exceeds nl, oil in excess of the amount of leakage is discharged from the hydraulic pump, and the car starts moving. In this way, a large amount of oil that exceeds the amount of leakage is supplied to the pipeline between the hydraulic pump and the check valve (described later), generating high pressure and rapidly pushing the check valve open, causing a large Start-up shock and vibration occur. The car reaches a constant speed at time t2, starts decelerating at time t3, and stops at time t4. The hydraulic pump continues to rotate further and stops at time t5. The starting shock is mainly caused by the significant increase in the rotational speed of the hydraulic pump 6 when the car is started, so if the rotational speed is gradually increased as shown in Fig. 7, the car will start at time t11. Start up, and from then on, time t1□
l t131 t141 At t15, the route of constant speed running, deceleration, car stop, and hydraulic pump stop is followed. In this way, when the rotational speed is gradually increased, the impact becomes smaller, but the start-up delay increases, the operation time becomes longer, and the transportation efficiency deteriorates. In addition, when descending, the reverse valve is opened by the energization of the electromagnetic coil, and the pressure oil from the hydraulic cylinder is returned to the oil tank. There is no oil, and the hydraulic pump has no power to stop this flow. Therefore, the oil from the hydraulic cylinder is suddenly returned to the oil tank through the pipe, which causes a start-up shock, which causes problems such as worsening the riding comfort of the car.

This invention has been made to solve the above problems, and an object of the present invention is to provide a control device for a hydraulic elevator that suppresses sudden changes in flow rate and pressure and can smoothly start a car.

[Means for solving problems]

A control device for a hydraulic elevator according to the present invention detects the pressure exerted on oil by the weight of a car and the temperature of oil passing through a hydraulic pump, and generates a pressure signal and an oil temperature signal after a predetermined period of time after an operation command is issued. The leakage amount of the hydraulic pump is calculated from this, the oil temperature signal, and the leakage coefficient of the hydraulic pump, and this leakage amount signal and the following running pattern signal are used as pattern signals to control the electric motor. It is something to control.

[Effect]

In the hydraulic elevator control device according to the present invention,
At least the pressure signal is held for a predetermined period of time after the operation command is issued, and the amount of leakage from the hydraulic pump is calculated, so that the amount of leakage is calculated in a state where load fluctuations caused by getting on and off the car are stable.

〔Example〕

1 to 5 are diagrams showing an embodiment of the present invention.

In the figure, (1) is the elevator hoistway, and (2) is the hoistway (1
), (3) is the pressure oil filled in the hydraulic cylinder (2), (4) is the plunger that moves up and down with the pressure oil (3), and (5) is the top of the plunger (4). A car installed on the car, (6) a cam attached to the heel (5), and (7) a deceleration command that is installed on the hoistway (1) and issues a deceleration command signal (7a) when engaged with the cam (6). The switch (8) is the stop command switch that also issues the stop command signal (8a), (9) is the floor, and α0 is the pipe (
11B) Detect the pressure exerted on the oil by the weight of the K-connected cage (5) (hereinafter referred to as cage pressure), and calculate the pressure kip 8'(l
oa), the α force always functions as a check valve, and when the electromagnetic coil (ImA) is energized, it is switched to allow the flow to pass in the opposite direction. (11B"l is the electromagnetic switching valve) A pipe line connected between the valve αυ and the hydraulic cylinder (2) to send and receive pressure oil; (2) is a hydraulic line that rotates reversibly and sends and receives pressure oil to and from the electromagnetic switching valve αυ via the pipe line (12A). pump, a3 is a three-phase induction motor that drives the hydraulic pump (2), C14) is a speed change detection word that is directly connected to electric motor α3 and detects its rotational speed and generates a speed signal (14a), αQ is a pipe line An oil tank that sends and receives oil to and from the hydraulic pump (2) via (15A), 0Q is an oil@detector that is installed inside the oil tank α, and detects the oil temperature and issues an oil temperature signal (16a). ,
R, S, and T are three-phase AC power supplies, Ql) is a rectifier circuit that converts three-phase AC to DC, (A) is a smoothing capacitor that smoothes the DC output of rectifier circuit Q1), and Han is a transistor and diode for DC input. An inverter that converts into variable voltage/frequency three-phase alternating current by controlling the pulse width with a circuit consisting of (
C) is connected between the AC power supplies R, S, and T and the DC side of the inverter wire, and converts the DC regenerated power into AC power.
The regenerative inverter returns to S and T, (to) pressure signal (LOA), oil @ signal (16a), speed signal (14a)
), a speed control device that inputs a deceleration command signal (7a), a stop command signal (8a), and a later-output operation command signal (to) and generates a control signal 'j) (25a) for controlling the transistor of the inverter blade; (30a) to (30C) are magnetic contactor contacts for operation that are inserted between the inverter blade and the motor α9 and are closed from when a start command is issued until a stop command is issued;
To) When a driving command is issued to the hakato (5), the driving command signal becomes "H" and becomes "L" after the hakato (5) stops, and when the driving command signal (to) becomes rHJ, there is a predetermined time delay. hand(
A delay circuit that emits an output (between time 1 and -12o in FIG. 3),
(G) is a delay circuit that outputs an output after a certain period of time when the output of the delay circuit (to) is input, and (41U) is a delay circuit (
7) output, deceleration command signal (7a) and stop command (B
Enter Ji+ (8a) to accelerate when climbing, high speed constant speed,
Climb travel pattern signal that commands deceleration and low constant speed (
41Ua), an upward running pattern generation circuit (4
LD) is a descending travel pattern generating circuit that also generates the descending travel pattern signal (4xDa), (41UA) is a rising relay contact that is closed during the ascending operation period, and (41DA) is a descending relay that is closed during the descending operation period. Contact point (c) is pressure signal 1 (loa) and oil r! A signal (16a)
is input, and when the output of the delay circuit becomes rHJ, it is output as a pressure signal (43a) and oil temperature signal (4sb), respectively, and when the output of the delay circuit (to) becomes "L", a pressure signal (4sb) is output.
3a) and a holding circuit that releases the holding of the oil temperature signal (43b); the foundation is a leakage coefficient correction circuit that stores or sets the leakage coefficient value of the hydraulic pump (2) and issues a leakage coefficient value signal (44a); (c) inputs the pressure signal (43a), oil@hakugo (43b), and leakage coefficient value signal (44a), calculates the 0 formula that will be given later, and calculates the leakage amount corresponding to the leakage amount from the hydraulic pump@. When the output of the delay circuit (to) becomes "H", the arithmetic circuit outputs the signal No. (45a), and the circuit (■) emits a bias pattern signal (46a) that causes the hydraulic pump @ to rotate at a rotational speed corresponding to the leakage amount at that time. The bias pattern generation circuit (0'i) generates the rising or falling running pattern signal (41
Ua), (41Da) and bias pattern signal (46
a) and outputs a pattern signal (47a), and in this embodiment, an adder is used.The 5 decoy is a conversion circuit that converts the speed signal (14a) to the same voltage level as the pattern signal. , Gin is the pattern signal (4
7a) and an adder 3' that outputs the deviation of the output of the conversion circuit (goods).
ω is a transmission circuit that transmits the outputs of the adders θ at a predetermined amplification degree, and (51) is the output of the transmission circuit ω and the conversion circuit (
Add the outputs of c) to get the frequency command @number ω. (52) is a frequency command signal ω. On the other hand, a function generating circuit (53) is a function generating circuit to which a voltage command signal (2) that varies linearly, for example, is a frequency command signal (ω). and voltage command signal v to the transistors in the inverter (c) so that a sine wave three-phase alternating current is output from the inverter wire.
This is a reference sine wave residual circuit that generates a control signal (ZSa).

Next, the operation of this embodiment will be explained.

Suppose now that the car (5) is stopped and a call is made in the upward direction. Pressure signal 'jl- (loa) and oil temperature signal (1
6a) is always output, and the holding circuit (c) is not in the holding state, so the above signals (10a) and (16a) are directly output as the pressure signal (43a) and oil temperature signal (43b"l).
It is output as . In addition, the leakage coefficient correction circuit 1 also receives a leakage coefficient value signal (44a) stored or set in advance.
It's in full force. Therefore, the arithmetic circuit (c) also operates at all times and outputs the leak amount signal (45a).

That is, generally a hydraulic pump (2) for a hydraulic elevator.
An IMO type screw pump is used, and the leakage amount of this hydraulic pump (2) is expressed by the following formula depending on the pump discharge pressure, oil temperature, and pump customization.

Here, Q: Leakage amount from the pump: Leakage coefficient due to variations in pump manufacturing P: Pump discharge hole pressure: Engler viscosity of oil that changes in response to oil temperature Calculation circuit ■ calculates the above equation 0. Basket (5)
During operation, the pump discharge hole pressure P is the pressure signal (LOA), and the viscosity E is the oil temperature signal 'i! r (x6a) and the coefficient correspond to the leakage coefficient value signal (44a) K, respectively.

It is this leakage tQ that causes a shock when starting the car (5).
This is because it has not been corrected. Therefore, basket (5)
Detects the car pressure and oil temperature during startup and running before the car (5) starts, gives a leakage coefficient value, calculates the leakage amount from these, and corrects the leakage amount when the car (5) starts up and runs. Then, the discharge pressure of the hydraulic pump (2) will not change suddenly, so the startup shock can be suppressed.5For example, when the car (5) is about to answer 8 calls without any load, the car pressure is 15 kg. /am2, oil temperature is 3
Assuming that the viscosity E at 5°C is 4.9 and the leakage coefficient K of the hydraulic pump powder is 6, the following equation is obtained, and the amount of leakage at startup and during running in this state is approximately 10.51'. This leakage amount tuna': leakage amount signal (45a) is output from the arithmetic circuit.

Therefore, while the car (5) is open and passengers are getting on and off, the pressure signal (loa) changes, so the leakage signal (
45a) is also constantly changing.

When the closing of the door is nearing completion at time t8 in FIG. (c)
1 holds the pressure signal (loa) and oil temperature signal (16a) at that point, and converts it to the pressure signal (43a).
and output as an oil temperature signal (43b). The arithmetic circuit (2) calculates these signals (43a), (43b) and each coefficient value signal (44a), and provides a constant value leakage amount signal (45a) to the bias pattern generation circuit (4).

When the door is closed and the starting conditions are met, a starting command is issued, and the operating electromagnetic contactor contacts (30a) to (30C) are closed.
The electric motor 03 is connected to the inverter wire. In addition, the bias pattern generation circuit (4e) generates a bias pattern signal Ji+ (46a) based on the above calculation result shown in FIG.
, ) occurs. This signal (46a') is added to adder 07)
becomes a pattern signal (47a) through adder 0!
jl calculates the deviation from the speed signal (14a) via the conversion circuit (goods), and sends it to the adder (51) via the transmission circuit ω.
is input. Here, the frequency command signal ω is added to the speed signal (i4a). and the function remainder circuit (52
) becomes the voltage command signal v. These signals ω. .

By ■, the reference sine wave generation circuit (53) is
25a) is emitted, the transistor of the inverter (c) is controlled in pulse width, and a three-phase alternating current of low voltage and frequency according to the bias pattern signal (46a) is passed from the inverter wire. Now, the electric motor α3 is connected to the hydraulic pump (6) at a low rotational speed equivalent to the leakage amount of the hydraulic pump (2).
to drive. Therefore, the bias pattern signal (46
In a), the car (5) does not rise.

At time t21, the output of the delay circuit becomes "H", and the upward running pattern generating circuit (41U) outputs the signal shown in FIG. 3(a).
) is determined as the upward running pattern signal (41Ua). At this time, connect the rising relay contact (4xcrA).

Since the adder θη is closed, the pattern signal (47a) shown in FIG. Ru. That is, after time t2□, the hydraulic pump (2) sends out more pressure oil than its leakage amount. The oil is transferred from the oil tank αQ to the pipe (15A) to the hydraulic pump to the arm passage (
12A) - Electromagnetic switching valve a - Pipeline (lIE) - Hydraulic cylinder (2) The oil is sent to the hydraulic cylinder (2) through the route, and the oil (5) is raised by an amount corresponding to this oil layer.

The hydraulic pump (12) is accelerated and eventually reaches a constant speed. At time t2□, when the car (5) reaches a point a predetermined distance before the called floor, the cam (6) activates the deceleration command switch (7). The car is engaged, and a deceleration command @ number (7a) is issued.The ascending travel pattern signal (41 [7a)] gradually decreases and eventually comes to output a constant value.Car (5)
continues to rise at a low speed in accordance with this, and at time t23, the cam (6) engages with the stop command switch (8) and the stop command signal (8a) is illuminated, and the upward travel pattern signal (4
1σa) further decreases and becomes zero at time t24. on the other hand,
The bias pattern signal (46 &) also begins to decrease at time t23 and becomes zero at time t25. For this reason, the pattern belief J
i! r(47a) rapidly decreases between time t23 and time t24. The cage (5) is connected to a hydraulic pump (2).
) becomes less than the amount equivalent to the leakage amount t26
Stop at.

During this time, the leakage fault signal (451L3) from the arithmetic circuit () is the value held when the door is closed, and the bias pattern generation circuit (g) also outputs the bias pattern signal (46a).
is emitting. However, when the car (5) stops and the door opens and the operation command signal (to) becomes rLJ, the signal holding state of the holding circuit is released and the leakage amount deviation (45a) changes every moment, but there is a delay. Since the output of the circuit (to) is "L", the bias pattern signal (46a) is not generated.

Next, the descending operation will be explained.

Now, when the car (5) is stopped and there is a call in the descending direction, the operation command signal (to) is sent at time t1 in Fig. 4, as in the case of ascending.
When it becomes "H", the output of the delay circuit (to) becomes rHJ at time t30 after a predetermined time, and the pressure signal (X
Oa) and the oil temperature signal (X6a) are held in a holding circuit, and the arithmetic circuit (c) gives a constant value to the bias pattern generation circuit. When the starting conditions are met, the bias pattern signal (46a) is determined as in the case of rising, thereby controlling the rotation speed of the electric motor α, and driving the hydraulic pump (2) to correct the leakage amount and Oil is supplied to the pipe (15A). In addition, the electromagnetic coil (1
1A) is also energized, but since there is a delay in operation, the pipe (12A) and pipe (llB)'ri are gradually brought into communication.

At time t, an output is generated from the delay circuit θ0, and the lower
(3) A descending traveling pattern signal (41Da) shown in FIG. 4(a) is determined from the descending traveling pattern generating circuit (41D). Therefore, the pattern signal shown in FIG. 4(C) is generated from the adder 0η (47a) is output. The electric motor 03 is controlled by the pattern signal (47a) and starts to gradually decelerate from time t31. Along with this deceleration, oil flows from the hydraulic cylinder (2) into the oil tank αυ Z0. Electric motor a3 reverses after stopping at time z1, starts decelerating when the deceleration command signal (7a) is output at time t3□, and stops at time z2.5 Between time z1 and time 22, electric motor α3 is under hydraulic pressure. Since it is driven by the pump@, it acts as an induction generator and returns the regenerated power to the AC power supplies R, S, and T via the regenerative inverter (c).After time z2, the electric motor (
) rotates forward again. At time t33, the stop command signal (
When 8a) is issued, the magnetic coil (IIA) that controls the electromagnetic switching valve αnl7)' is deenergized, the electromagnetic switching valve α→ returns to its original state, and the outflow of pressure oil from the hydraulic cylinder (2) is prevented, and the car ( 5) is stopped.

On the other hand, the downward running pattern signal (41Da) also occurs at time t3.
It starts to decrease at 3 and becomes zero at time t34. Similarly, the bias pattern signal (46a) begins to decrease at time t33 and becomes zero at time t35. Travel pattern signal (47
a) becomes a constant value for a while after time t33, and at time t3
The decrease q starts from 4 and becomes zero at time t35. Electric motor α1
is controlled by this pattern signal (47a) to drive the hydraulic pump (2).

In this way, the car pressure and oil temperature are detected prior to starting the car (5), and the leakage coefficient of the hydraulic pump (c) is stored or set in advance, and the leakage amount is calculated from these and calculated. This value is used to generate a bias pattern signal (46a), and the electric motor α1 is operated at a low speed to compensate for the leakage fit of the hydraulic pump (2). By adding (41Ua) and (41Da), motor α3
I am trying to start it. Therefore, when ascending, the hydraulic pump (2) is prevented from suddenly discharging a large amount of oil, and when descending, the rapid flow of oil is suppressed, so the car (5) can be moved without vibration. It can be started smoothly.

Here, the timing of holding the pressure signal (LOA) and the oil 1 signal (16a) will be explained with reference to FIG.

The leakage amount signal (45a) issued at the time of startup is the pressure signal (1
0a) and the oil temperature signal (16a).
Figure 5(b)). This means, for example, that Kato (5) stops and
This is to prevent the load pressure from fluctuating due to passengers or luggage getting on and off from the time t0 when the door begins to open until the time when the door closes. That is, when the load pressure changes significantly, the load pressure mainly changes due to the natural period T of the system. It vibrates. Therefore, the pressure signal (1o
If a) is input, in some cases, as shown in FIG. 5(a), a pressure signal ji) (10a) with a large error will be input. On the other hand, the delay time (between time t and -t2o) is the natural period T of the system.

If the value is about 1/2, the vibration is considerably damped, so the error can be sufficiently reduced, and the leakage signal can be corrected more accurately.

In addition, the operation command signal (c) input to the delay circuit (to)
may be a door closing completion signal, and the door position signal of the door closing machine after the time when the door is closed to the extent that passengers or luggage cannot get on or off the vehicle may be used as the door closing completion @ sign.

In addition, since the pressure signal (43a) and oil temperature signal (43b) are held until the door is opened after the car (5) stops running, the amount of leakage from the hydraulic pump (a) can be corrected while the car is running. It becomes possible to maintain the speed change in (5) constant, and it is possible to shorten or omit low-speed running time and improve landing precision. In addition, it is desirable that the amount of leakage is corrected by the amount equivalent to the bone leakage, but the running pattern signal (4ura), (
41Da) If the delay time until occurrence is shortened,
Even if the amount of correction is a little large, the impact will be small.

Note that the inputs to the holding circuit were the pressure signal (LOA) and the oil temperature signal (16a), but based on the actual situation, either one was used and the other was input to the calculation circuit (c) to calculate the leakage amount. However, it can be put to practical use.

Furthermore, although the leakage coefficient value No. 18 (44a) is input to the arithmetic circuit (c), there is no problem in calculating the amount of leakage even if it is inputted via the holding circuit.

In the embodiment, bias pattern signal No. 1 (46a) and running pattern signals (41Ua) and (41Ua) are used prior to activation.
Da) is added, but it is also possible to switch to another pattern signal.

Note that the electric motor [alpha] that drives the hydraulic pump (6) is not limited to an induction motor, and any electric motor that is variably controlled by a pattern signal can sufficiently achieve the intended purpose.

〔Effect of the invention〕

As described above, the present invention detects the weight of the car of a hydraulic elevator, the pressure applied to the oil, and the temperature of the oil passing through the hydraulic pump. Among the signals, at least the pressure signal is held, and the leakage amount of the hydraulic pump is calculated from this, the oil temperature signal, and the leakage coefficient of the hydraulic pump, and this leakage amount signal and the following driving pattern signal are respectively calculated. The electric motor is controlled as a pattern signal.This allows the leakage amount to be calculated while the load fluctuations caused by getting on and off the car are stabilized, suppressing sudden changes in flow rate and pressure, and starting the car smoothly. can be done.

[Brief explanation of the drawing]

1 to 5 are diagrams showing one embodiment of a hydraulic elevator control device according to the present invention, in which FIG. 1 is a block circuit diagram of the speed change control device shown in FIG. 2, and FIG. 2 is an overall configuration diagram; Fig. 3 is an explanatory diagram of the operation of the upward operation, Fig. 4 is an explanatory diagram of the operation of the downward operation, Fig. 5 is an explanatory diagram of the operation of the delay circuit (to) of Fig. 1, and Fig. 6 is an explanatory diagram of the operation of the delay circuit (to) of Fig. 1.
7 and 7 are explanatory views of the operation of a conventional hydraulic elevator control device. In the figure, (2) is the hydraulic cylinder, (5) is the cage, 00 pressure detector, (c) is the hydraulic pump, α] is the three-phase induction motor, 0Q is the oil temperature detection word, and (to) is the operation command. signal, (to) is the delay circuit, (41U) is the upward running pattern generation circuit, (
41D) is a downward running pattern generation circuit, ■ is a holding circuit,
09 is an arithmetic circuit, (c) is a bias pattern generation circuit,
(4η is a pattern generation circuit (adder). Note that the same reference numerals in the figures indicate the same parts.

Claims (1)

[Claims] (1) A running pattern generation circuit that generates a running pattern signal in a motor that controls an electric motor according to a pattern signal, and when a driving command signal is issued, a hydraulic pump is driven by the electric motor to cause the car to run. , a pressure detector that detects the pressure exerted on the oil by the weight of the car, an oil temperature detector that detects the temperature of the oil passing through the hydraulic pump, a delay circuit that delays the operation command signal by a predetermined time and outputs it;
A holding circuit that holds at least the output of the pressure detector out of the output of the pressure detector and the output of the oil temperature sensor using the output of the delay circuit; the output of this holding circuit or the output of this holding circuit and the output of the oil temperature sensor; and a pattern generation circuit that generates the travel pattern signal as the pattern signal after generating the leak rate signal as the pattern signal. A hydraulic elevator control device characterized by: