JPH0151434B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a control device for a hydraulic elevator that controls a flow rate according to a pattern signal to run a car.

[Prior art]

Figures 1 to 5 show a conventional hydraulic elevator control system. In the figures, 1 is a hoistway, 2 is a cylinder buried in a pit in the hoistway 1, and 9 is pressure oil filled in this cylinder. , 4 is a plunger supported by this pressure oil, 5 is a cage placed on the top of this plunger 4, 5a is a floor, and 6 is a floor 5 of this cage.
A load detection device is installed under a, 7 is a landing floor, 8 is a cam attached to the car 5, 9 is a deceleration command switch for decelerating the moving car 5, and 10 is for stopping the car 5. The stop command switch 11 always functions as a check valve, and when the electromagnetic coil 11b is energized, it is switched and conducts in the opposite direction.The electromagnetic switching valve 11a is a switch between the cylinder 2 and the electromagnetic switching valve 11. 12 is a hydraulic pump that rotates reversibly and sends and receives pressure oil to and from the electromagnetic switching valve 11 via the pipe 12a, and 13 is a three-phase induction that drives this hydraulic pump 12. The electric motor 14 is this three-phase induction motor 13
15 is a tube 15a that detects the rotation speed of the speed generator.
An oil tank that sends and receives pressure oil to and from the hydraulic pump 12 via. 16 is an oil temperature detection device that detects the oil temperature in the oil tank 15; R, S, and T are three-phase AC power supplies; 21 is a rectifier circuit that converts three-phase AC into DC; 22 is a capacitor that smoothes this DC; 23 is an inverter that controls the pulse width of DC to generate three-phase AC with variable voltage and variable frequency; 24 is a regenerative inverter that returns the DC to three-phase AC power supplies R, S, and T; 25 is the load of the load detection device 6 Signal 6a and speed generator 1
4, the oil pressure signal 16a of the oil temperature detection device 16, the deceleration command signal 9a, and the normally open contact 30Tc, which is closed from when a start command is issued until a stop command is issued. A speed control device to which a command signal and a signal 30da generated by a normally open contact 30d of an operating contactor are respectively input,
The inverter 23 is controlled by outputting a signal 25a. 30a to 30c are normally open contacts of the operating contactor 30 shown in FIG. 3, which connect the three-phase induction motor 13 to the inverter 23.

FIG. 2 shows details of the speed control device 25 shown in FIG. 1, and 40 is a delay circuit 41U that outputs an output after a predetermined time delay after the normally open contact 30Tc closes.
is an upward running pattern generation circuit, which _starts at time _t1 as shown in FIG. It becomes zero at time _t6 . Reference numeral 41D is a downward running pattern generating circuit which outputs a running pattern signal shown in FIG. 4b'. 41Ua is an upper contact that remains closed during upward operation; 41Da and 41Db are lower contacts that remain closed during downward operation; and 42 is a contact that remains closed during upward operation. A setting bias pattern circuit that initializes the amount of leakage and issues a command to rotate the hydraulic pump 12 at a rotation rate equivalent to the amount of leakage in the hydraulic pump 12 at a predetermined temperature with no load; 43 is a computing unit; It operates based on the oil temperature signal 16a and the load signal 6a, and adds and corrects the output of the setting bias pattern circuit 42 via the adder 44.
45 is a bias pattern generating circuit that issues a command to rotate at a rotation speed corresponding to the amount of leakage of the hydraulic pump 12 at that time when the normally open contact 30Tc is closed, and becomes zero when the stop command signal 30d is issued. be. 46 is a running pattern generation circuit 41U or 4
An adder which adds the output of 1D and the output of the bias pattern generation circuit 45 and outputs the pattern signals shown in FIG. 4c and c'. 47 is a conversion circuit that converts the speed signal 14a to the same voltage level as the pattern signal; 48 is a subtracter that takes the difference between the output of the adder 46 and the output of the conversion circuit 47; and 49 is a predetermined value for the output of this subtracter 48. 50 is an adder that adds the output of the transmission circuit 49 and the output of the conversion circuit 47 to output a frequency command signal ω ₀ ;
51 is a function generating circuit that generates a linear voltage command signal V in response to the frequency command signal ω ₀ of this adder 50, and 52 is a frequency command signal ω ₀ and a voltage command signal V
This is a reference sine wave generation circuit that outputs a signal 25a so that a three-phase sine wave AC is output from the inverter 23 based on the sine wave.

Figure 3 shows the control circuit connection diagram, (+), (-)
8 is a control power supply, 8 is a start command circuit that is closed by a call signal, a door closed detection signal, etc., 30T is a control power supply (+) at one end via the start command circuit 28, and a control power supply (-) at the other end. The operation command time relay 30Ta connected to is the normally open contact of this time relay 30T, and one end is the normally closed contact 10 of the stop command switch 10.
The other end is connected to one end of the time relay 30T via c to the control power source (+). 30Tb is the normally open contact of the timed relay 30T, 30Tc,
30Td is the normally open contact of the time relay 30T,
Reference numeral 30 denotes an operating contactor controlled by a normally open contact 30Tb, which includes normally open contacts 30a and 30 shown in FIGS. 1 to 3.
b, 30c, 30d, and 30f are opened and closed.

Next, the operation will be explained. When the car is stopped and there is a call in the upward direction, a start command is issued to the car 5 after the door has been closed, and the time relay 30T is energized. This time relay 30T maintains itself when the car 5 starts moving and leaves the stopping point.

When the operating contactor 30 is excited by the time relay 30T, power is supplied to the motor 13 through the normally open contacts 30a to 30c, and a signal is output from the bias pattern generation circuit 45 through the normally open contact 30Tc.
The bias pattern retains its value at time t ₀
A bias pattern occurs. With this bias pattern, the inverter 23 emits a three-phase alternating current of low voltage and frequency, and the electric motor 13 drives the pump 12 at a low rotation rate corresponding to the leakage of the hydraulic pump 12 calculated in advance. Therefore basket 5
will never rise.

After a certain period of time after the time relay 30T is excited, an output is issued from the delay circuit 40 at time t ₁ , a running pattern is output from the upward running pattern generation circuit 40U, and the bias pattern and running pattern are as shown in Fig. 4c.
The amount of pressure oil supplied from the pump 12 gradually increases to push the check valve 11, and the car 5 starts running as shown in FIG. 5, and eventually reaches a constant speed at time _t2 . When the car 5 comes to a predetermined position in front of the destination floor, the cam 8 activates the deceleration command switch 9.
Then, at time _t3 , the upward running pattern generation circuit 41U
gradually decreases and decelerates, and eventually reaches a constant low speed and car 5 continues to rise. When the cam 8 operates the stop command switch 10 at time _t5 , the start command circuit 28
is opened by the operation of the deceleration command switch 9, and when the normally closed contact 10b is opened, the time relay 30
Since T is deenergized and the output of the ascending travel pattern generation circuit 41U has fallen to zero, the travel pattern further decreases and the discharge amount to the cylinder 2 decreases, so the check valve 1
Car 1 gradually closes, and at time _t6 , car 5 almost comes to a halt. Although the time relay 30T is deenergized, the time limit contact 30Tb remains closed for a certain period of time, so the time relay 30 is in an energized state and the motor 13 continues to rotate due to the bias pattern signal. When the time limit contact 30Tb is opened after the time limit, the time limit relay 30
Due to the deenergization of the normally open contacts 30a to 30c at time _t7
The power supply to the electric motor 13 is cut off at the normally open contact 3.
0d, the bias pattern generation circuit 45 is also cut off, and at time _t8 , the electric motor 13 and the car 5 are stopped.

Next, when there is a down call, when a start command is issued after the door is closed, the time relay 30T is energized, the contact 30Tb is closed, and the time relay 30 is energized.
By closing the contacts 30a to 30c, power is supplied to the motor 13, and a bias pattern is generated.
At time t ₀ ', the pump 12 rotates at a low speed in the direction of discharging oil from the pump 12, as in the case of rising. This corrects the leakage. Further, the solenoid valve coil 11b is energized by the contacts 30f and 30Tb, and the valve 11 is opened.

After a certain period of time, an output is issued from the delay circuit 40, and at time t' ₁ , the downward running pattern generation circuit 41D
The running pattern is output as shown in Figure 4c.
The bias pattern and the running pattern are added, and therefore the motor 13 gradually lowers its rotation and rotates from zero rotation to the reverse direction, and the car 5 runs in the downward direction as shown in FIG. 5, and eventually reaches time t' ₂ The speed becomes constant. When the cam 8 operates the deceleration command switch 9,
As with the ascent, it decelerates at time t′ ₃ , then reaches a constant low speed and continues descending. When the stop command switch 10 is operated, the running pattern is further reduced and the pump 12 is rotated by the bias pattern.
Since only the leakage amount is supplied, the car 5 almost stops at time _t'6 .

Furthermore, the operation of the stop command switch 10 demagnetizes the time relay 30T and opens the contact 30Td, so the solenoid valve coil 11b is demagnetized, the valve 11 gradually closes, and the oil from the cylinder 2 is stopped, so the car 5 is in a stopped state. keep it. Thereafter, as in the case of rising, the power supply to the electric motor 13 and the bias pattern are cut off at time _t'8 after a certain period of time, and the pump 12 is stopped.

Here, after the running pattern is completed, when the car is rotating slightly due to the bias pattern, the car is almost at a standstill, but both upward and downward movements move slightly in the upward direction.

This is because the bias pattern value for correcting leakage is calculated for the purpose of preventing shock at startup, so it is calculated by taking into account static frictional resistance such as cylinder packing resistance and car hoistway resistance at startup. There is.

However, after the car starts moving, the above resistance becomes a frictional resistance value, which is generally smaller than static friction. Therefore, if the same bias pattern is applied after the car is started, the car speed will be slightly higher when rising and slightly lower when falling after starting, but this is not a problem in actual use. However, when landing on the floor, the above-mentioned resistance difference causes the car to rise slightly even when it reaches the target stop position, which increases the landing error.

[Summary of the invention]

The present invention has been made to eliminate such drawbacks, and proposes a control device for a hydraulic elevator that can slightly reduce the bias pattern value after the car is started, thereby reducing landing errors.

[Embodiments of the invention]

6 to 8 show an embodiment of the present invention, and the same reference numerals as in FIGS. 1 to 5 indicate the same or corresponding parts. 54 is a subtracter, and 55 is a correction pattern, which gradually increases the difference between the static frictional resistance and the dynamic frictional resistance to the final value in order to soften the shock.

Next, the effect will be explained.

In FIG. 7 and FIG. 8, time t ₀ to t ₃ , t′ ₀
~ _t'3 is the same as the conventional one.

When a deceleration command is issued at time t ₃ or t ₃ ′, the running pattern gradually becomes zero, and the correction pattern 5
5 is subtracted by the subtracter 54, and the bias pattern is reduced to compensate for the above difference, and the bias is lowered and corrected by time _t30 and _t30 '. As a result, the above-mentioned difference is corrected, so that after the running pattern becomes zero, the car does not run when only the bias pattern is used, and the car lands accurately at a low speed, thereby improving the landing accuracy of the car.

In this embodiment, the resistance difference from static to dynamic is corrected from the start of deceleration, but it may be corrected at any time after starting the car.

Further, although the correction pattern is increased gradually, it may be changed in a stepwise manner if some shock is allowed.

〔Effect of the invention〕

As described above, the present invention controls the flow rate according to a pattern signal to run a car, and the bias pattern signal that gives a low discharge amount is slightly lowered in signal value after the car is started compared to before the car is started.
This is to correct the difference in frictional resistance from static to dynamic.

This can reduce landing errors.

[Brief explanation of drawings]

Fig. 1 is a system diagram showing a conventional hydraulic elevator control system, Fig. 2 is a detailed diagram of the speed control device shown in Fig. 1, Fig. 3 is a control circuit connection diagram, and Fig. 4 is a bias pattern and running pattern. , FIG. 5 is a diagram showing the relationship between the motor pattern and car speed, and FIG. 6 is a diagram corresponding to FIG. 2 showing details of the speed control device according to the present invention.
FIG. 7 is a diagram corresponding to FIG. 4 showing changes over time in the bias pattern, running pattern, and motor pattern, and FIG. 8 is a diagram corresponding to FIG. 5 showing the relationship between the motor pattern and car speed. 2... Cylinder, 5... Car, 12... Hydraulic pump, 13... Three-phase induction motor, 25... Speed control device, 41U, 41D... Running pattern generation circuit, 42... Setting bias pattern circuit, 45 …
... Bias pattern generation circuit, 46, 50 ... Adder, 47 ... Converter, 48, 54 ... Subtractor,
52...Reference sine wave generation circuit, 55...Correction pattern. In each figure, the same reference numerals indicate the same or corresponding parts.

Claims (1)

[Claims] 1. A bias pattern generating circuit that generates a bias pattern signal to cause the pump to discharge a lower discharge amount, a circuit that holds the bias pattern signal, and a running pattern generating circuit that generates a running pattern signal and causes the car to run, In a car that runs a car by switching the running pattern signal or superimposing it with an adder and controlling the flow rate according to this pattern signal, it is recommended to set the bias pattern signal after starting the car to a slightly lower value than before starting the car. A hydraulic elevator control device featuring features.