JPH04266376A - Hydraulic elevator control device - Google Patents

Abstract

PURPOSE:To provide a hydraulic elevator control device capable of restricting the acceleration of a cage at the time of an emergency stop. CONSTITUTION:A synchronous motor is used for controlling elevation of a cage. A series circuit comprising a resistor and a switching means is inserted between the input terminals of the synchronous motor so that the switch means is short-circuited at the time of any emergency stop of the cage to cause the synchronous motor to produce braking effect by its power generating action via a resistor.

Description

[Detailed description of the invention]

0001

[Field of Industrial Application] This invention relates to a control device for a fluid pressure elevator controlled by a VVVF (variable voltage variable frequency) device, and in particular to a control device for a fluid pressure elevator that can suppress acceleration by dynamic braking in an emergency. be.

0002

[Prior Art] Conventionally, a control method using a flow control valve has been common as a speed control device for a hydraulic elevator using hydraulic pressure, etc., but a motor rotation speed control method with less energy loss has been proposed. There is. The electric motor rotation speed control system suppresses the energy loss by sending only the required amount of pressure oil when ascending and regeneratively braking the electric motor during descending. In addition, this method uses a variable voltage variable frequency (VVVF) inverter to control the rotation speed of the induction motor over a wide range, and uses a constant discharge pump to control the discharge amount by changing the rotation speed of the induction motor. can be controlled.

FIG. 2 is a block diagram showing a conventional fluid pressure elevator control device using an electric motor rotation speed control method, and FIG.
2 is a side view showing the pressure oil drive unit, that is, the elevator drive unit, FIG. 4 is a wiring diagram showing the peripheral circuit of the operation command contactor not shown in FIG. 2, and FIG. 5 is a side view of the speed control device in FIG. A block diagram showing details, and FIG. 6 are waveform diagrams showing each pattern.

In FIG. 2, a cylinder (2) is installed at the bottom of the hoistway (1), and the cylinder (2) is filled with pressure oil (3).
) is filled. A barb wheel (4a) is provided on the top of the plunger (4) supported by pressure oil (3), and a rope (7) with one end fixed is hung around the barb wheel (4a). The other end of the rope (7) is connected to an elevator car (hereinafter simply referred to as a car) (5), and the car (5) is supported so as to be movable up and down along a guide rail (6). A cam (
8), and a plurality of deceleration command switches (9) and stop command switches (10) are provided on the inner wall of the hoistway (1) so as to face the cam (8). Also, the hoistway (
1) A plurality of landing floors (not shown) are installed on the side wall.

Pressure oil (3) in the cylinder (2) is supplied to the pipe (11
a) to the electromagnetic switching valve (11). The electromagnetic switching valve (11) always functions as a check valve, and conducts in the opposite direction when the electromagnetic coil (11b) is energized. The electromagnetic switching valve (11) is connected via the pipe (12a).
) is rotated in both directions by a three-phase induction motor (13) and is connected to an electromagnetic switching valve (11
) to send and receive pressure oil (3). The induction motor (13) is provided with a pulse encoder (14) for detecting the number of rotations. Also, hydraulic pump (12)
is provided with a tank (15) for storing pressure oil (3), and the pressure oil (3) is sent and received via a pipe (15a). The surrounding structure of the elevator drive unit including the hydraulic pump (12) is as shown in FIG. 3, and the hydraulic pump (12) is connected to the tank (
15).

The number of rotations, that is, the speed of the induction motor (13) is V
The inverter circuit (20) that performs VVF control includes a rectifier (21) that receives three-phase AC power supplies R, S, and T as input, and a rectifier (
21), an inverter (23) that controls the pulse width of the DC voltage between both ends of the capacitor (22) and outputs a three-phase AC voltage using VVVF, and consumes regenerative power. capacitor (
resistor (24) connected in parallel to resistor (22);
4) Control transistor (24a) connected in series with
It is equipped with

Induction motor (13) and inverter circuit (2)
0), normally open contacts (30a) to (30c) of the operating contactor (30) (see FIG. 4) are inserted. Speed control device (25) for controlling the inverter (23)
is the deceleration command signal (9a) from the deceleration command switch (9).
), the speed signal (14a) from the speed generator (14), the operation command signal via the normally open contact (30Tc) of the operation command time relay (30T) (see Figure 4), and the operation contactor (
A control signal (25a) is output based on the operating signal via the normally open contact (30d) of the controller 30).

In FIG. 4, an operation command time relay (30
T), the operating contactor (30), the electromagnetic coil (11b) and the speed control device (25) are connected in parallel to the control power sources (+) and (-), respectively. The operation command time relay (30T) is connected in series with a start command circuit (28) that is opened by the deceleration command signal (9a) and closed by the call signal, door closed detection signal, etc. 28) is equipped with a stop command switch (10) (Fig.
(see) normally closed contact (10b) and operation command time relay (
A series circuit consisting of normally open contacts (30Ta) of 30T) is connected in parallel. An abnormality detection relay (not shown) is attached to the operation command time relay (30T) and operation contactor (30).
normally open contacts (29a) and (29b) are individually connected in series. The normally open contacts (29a) and (29b) are normally closed because the abnormality detection relay is normally in an energized state.

[0009] A normally open contact (30Tb) for timed return of the operation command time relay (30T) is connected in series to the operation contactor (30). The electromagnetic coil (11b) includes a normally open contact (30f) of the operation contactor (30), a normally open contact (30Td) of the operation command time relay (30T), and a downward contact that is closed only during the downward operation period. A contact (41Db) is connected in series.

FIG. 5 shows the speed control device (25) in detail.
In the delay circuit (40), the operation command time relay (
30T) via the normally open contact (30Tc) is delayed for a certain period of time and output. Upward running pattern generation circuit (41U) and downward running pattern generation circuit (41D)
Each generates a predetermined running pattern based on the driving command signal delayed by the delay circuit (40), and switches the running pattern to a low speed based on the deceleration command signal (9a). The output terminal of the upward running pattern generation circuit (41U) has an upward contact (41U) that is closed only during the upward running period.
a) is connected, and the downward running pattern generation circuit (41D)
A downward contact (41Da) that is closed only during the descending operation period is connected to the output terminal of.

The bias pattern generation circuit (45) generates a hydraulic pump at that time based on an operation signal via the normally open contact (30d) of the operation contactor (30) and an operation command signal via the normally open contact (30Tc). A bias pattern is generated to rotate the hydraulic pump (12) at a rotation speed corresponding to the amount of leakage of the pressure oil (3) in (12), and the normally open contact (30d)
The bias pattern is made zero by the stop command signal caused by opening of the bias pattern. The adder (46) adds the bias pattern to the output of one of the running pattern generation circuits (41U) and (41D).

The conversion circuit (47) converts the speed signal (14a)
match the level of each running pattern. The subtracter (48) is the output of the adder (46) and the conversion circuit (47)
The subtraction result is input to the transmission circuit (49). The adder (50) adds the output of the conversion circuit (47) to the output amplified by the transfer circuit (49) and outputs a frequency command signal ωo. The function generator (51) generates a voltage command signal V that changes linearly with respect to the frequency command signal ωo.
occurs. The reference sine wave generation circuit (52) outputs a control signal (25a) to the inverter (23) based on the frequency command signal ωo and the voltage command signal V. The control signal (25a) causes the inverter (23) to generate a sinusoidal three-phase AC voltage.

In FIG. 6 showing each pattern waveform, (a
) is the bias pattern, (b) is the running pattern during descent, (c) is the motor pattern corresponding to the rotation speed of the induction motor (13), (d) is the speed pattern of the car (5), (e
) is the flow rate pattern of the pressure oil (3) corresponding to the actual output.

Next, the specific operation of the conventional hydraulic elevator control system shown in FIGS. 2 to 5 will be described with reference to the waveform diagrams of each pattern in FIG. 6. Incidentally, since the ascending and descending running patterns differ only in polarity, only the descending running pattern will be described here. Assuming that the car (5) is stopped and a call is made in the downward direction, a start command is input to the car (5) after the door has been closed. At this time, the operation command time relay (30T) in FIG.
It is self-retained by closing Ta), and the normally open contact (
30Tb) to (30Td) are closed.

By closing the normally open contact (30Tb), the operating contactor (30) is energized, and the normally open contact (30a) in FIG.
) to (30c) and (30d) and (30f) in FIG.
is closed. By closing the normally open contacts (30a) to (30c), the induction motor (13) is connected to the inverter (23) and powered. Also, normally open contact (30Tc) and (
30d), the bias pattern generating circuit (45) in FIG. 5 generates a bias pattern from time t0 as shown in FIG. 6(a). With this bias pattern, the inverter (23) outputs low voltage and low frequency three-phase AC, and the induction motor (13) outputs the hydraulic pump (12).
) The hydraulic pump (12) is driven at a low rotational speed corresponding to the leakage. Therefore, by driving the bias pattern, the car (5
) does not rise and the car (5) remains stationary.

[0016] Also, during descending operation, the normally open contact (41Da)
and (41Db) are closed, so the normally open contact (3
By closing 0f), (30Td) and (41Db),
The electromagnetic coil (11b) is excited, and the electromagnetic switching valve (11)
is opened and becomes fully open at time tp.

On the other hand, a certain period of time has passed since the normally open contact (30Tc) was closed by the excitation of the operation command time relay (30T), and at time t1, the delay circuit (40) generates an output, The downward running pattern generation circuit (41D) generates a running pattern starting from time t1 as shown in FIG. 6(b). At this time, the running pattern is added to the bias pattern by the adder (46), so the induction motor (13) gradually lowers the rotation speed and rotates in the reverse direction from the zero rotation speed. As a result, the car (5) travels in the downward direction, as shown in FIG. 6(d), and reaches a constant speed at time t2.

When the car (5) descends and reaches a predetermined position in front of the destination floor at time t3, the cam (8) operates the deceleration command switch (9) to generate a deceleration command signal (9a). As a result, the downward running pattern generation circuit (41D)
The pattern signal from the car (5) decreases, and the car (5) is decelerated from time t3, reaches a constant low speed at time t4, and continues to descend. At this time, the start command circuit (28) outputs the deceleration command signal (9
It is opened by a). Therefore, at time t5, cam (
8) operates the stop command switch (10) and opens the normally closed contact (10b), the operation command time relay (3)
0T) is deenergized. As a result, the output of the downward running pattern generating circuit (41D) drops to zero, so the running pattern further decreases, and the car (5) stops at time t6. At this time, even if the operation command time relay (30T) is deenergized, the normally open contact (30Tb) remains closed for a certain period of time and then returns, so the operation contactor (30) remains energized and the induction The electric motor (13) continues to rotate according to the bias pattern.

On the other hand, due to the operation of the stop command switch (10), the operation command time relay (30T) is deenergized and the normally open contact (30Td) is opened, so that the electromagnetic coil (11
b) is deenergized, and the electromagnetic switching valve (11) is gradually closed until it is fully closed at time tD. As a result, the supply of pressure oil (3) from the cylinder (2) to the tank (15) is stopped, and the stopped state of the car (5) is maintained. Then, at time t7, the normally open contact (30Tb) is opened and the operating contactor (30) is deenergized, and the normally open contacts (30a) to (30f) are opened. As a result, the power supply to the induction motor (13) is cut off, the bias pattern generation circuit (45) stops outputting the bias pattern, and the induction motor (13) stops at time t8.

The operation when the car (5) is raised is the same as described above, except that the direction of rotation of the induction motor (13) is opposite to that when it is lowered, and the electromagnetic switching valve (11) remains closed. It is almost the same as In this way, the inverter (23)
The control method according to the present invention exhibits good performance for hydraulic elevators. Furthermore, recently, for the purpose of noise prevention and miniaturization, hydraulic pumps (12) and induction motors (13) have been developed, as shown in Figure 7.
) is beginning to be adopted, in which the elevator drive unit is immersed in a tank (15). In this case, the electromagnetic switching valve (11), the hydraulic pump (12) and the induction motor (
13) and the speed generator (14) are immersed in the pressure oil (3) in the tank (15), but whether or not it is of the submerged type is irrelevant to this invention.

By the way, if a power outage occurs while the car (5) is full and descending at the rated speed, the contactors (30a) to
(30c) (see FIG. 2) is opened, the electromagnetic coil (11b) is deenergized, the electromagnetic switching valve (11) is closed, and the car (5) is stopped. However, at this time, until the electromagnetic switching valve (11) is closed, the induction motor (1
3) is in an uncontrolled state, and the pressure oil (30) is turned off by the hydraulic pump (
The car (5) is returned to the tank (15) only by the resistance of the car (12), and as a result, the car (5) becomes overspeeded and an emergency stop (not shown) is activated, making it impossible to restart the car.

[0022] In a fluid pressure elevator control system that does not use the VVVF control method, the flow rate of pressure oil during descent is controlled by providing a solenoid valve (not shown) exclusively for descent, so even in the event of a power outage, the electromagnetic The delay in valve operation is extremely small.
The above problem does not occur. However, the electromagnetic switching valve (1
1) To speed up the closing operation, one solenoid switching valve (1)
1) is extremely difficult structurally because it is used for both raising and lowering. In addition, in order to increase the resistance of the return oil, the induction motor (13) or hydraulic pump (12) is activated during a power outage.
There are methods that add a mechanical brake to stop the car, and methods that add a mechanical brake to stop the car (
In order to suppress the speed increase in step 5), a method of adding a flywheel to increase the inertia of the induction motor (13) has been proposed, but either method is unfavorable from the viewpoint of cost, space, or energy consumption. .

[0023]

[Problems to be Solved by the Invention] As described above, in the conventional fluid pressure elevator control system, when an emergency such as a power outage occurs, the car (5) is stopped by closing the electromagnetic switching valve (11). Until then, the induction motor (13) is in an uncontrolled state, and the pressure oil (30) is returned to the tank (15) only by the resistance of the hydraulic pump (12), so the car (5) is overspeeding. There was a problem in that the emergency stop was activated, making it impossible to restart.

The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide a fluid pressure elevator control device that can suppress speed increase of the car during an emergency stop.

[0025]

[Means for Solving the Problems] A fluid pressure elevator control device according to the present invention includes a synchronous motor for controlling the elevation of a car based on the flow rate of fluid, and an inverter circuit for determining the rotation speed of the synchronous motor by VVVF. , a speed control device for controlling an inverter circuit, and a series circuit consisting of a resistor and switch means inserted between input terminals of a synchronous motor.

[0026]

[Operation] In the present invention, the switch means is short-circuited during an emergency stop of the car, and the synchronous motor is dynamically braked via the resistor, thereby suppressing speed increase of the car.

[0027]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a configuration diagram showing an embodiment of the present invention,
(1) - (12), (14), (15), (21) - (
24), (24a), (25), (30a) to (30d
) and (30Tc) are the same as above. In this case, the rectifier (21) in the inverter circuit (20) is constituted by diodes (21a) to (21f), and is a three-phase full-wave rectifier circuit. Also, inverter (2
3) is constituted by an arm in which transistors (23a) to (23f) and diodes (23A) to (23F) are connected in antiparallel. Furthermore, a normally open contact (30a)
~(30c) are inserted on the input side of the inverter circuit (20).

Normally closed contact (30X) of operating contactor (30)
serves as a switch that is short-circuited in an emergency, and forms a series circuit with the resistor (24) to connect the synchronous motor (1
It is inserted between the input terminals of the transistor (24a) and connected in parallel to the transistor (24a). Also, normally closed contact (30
X) is connected to the resistor (24), for example, so as to short-circuit a part of the resistor (24). A synchronous electric motor (100) whose rotation speed is determined by VVVF by an inverter circuit (20) drives a hydraulic pump (12) to control the flow rate of pressure oil (3), and controls the elevator car (5) to move up and down. There is. Here, since a permanent magnet is used as the field of the synchronous motor (100), no particular excitation circuit is required.

Next, the operation of the embodiment of the present invention shown in FIG. 1 will be explained. If some abnormality occurs while the car (5) is running and the abnormality detection relay is deenergized and the normally open contact (29b) (see Fig. 4) is opened, the operation contactor (30) is deenergized. normally open contacts (30a) to (30c
) is open, and the inverter circuit (20) is connected to the three-phase power supply R,
Separated from S and T.

At the same time, the electromagnetic coil (11b) is deenergized, the electromagnetic switching valve (11) begins to close, and the car (5)
begins to stop. In addition, the normally closed contact (30X) is closed when the operating contactor (30) is deenergized, and the transistor (2
4a) and a part of the resistor (24).

At this time, the pressure oil (3) flows through the electromagnetic switching valve (1).
1), the water is returned to the tank (15) via the hydraulic pump (12). On the other hand, a synchronous motor (100
) is the diode (2) of each arm of the inverter (23).
3A) to (23F), a normally closed contact (30X), and a partially shorted resistor (24) to apply dynamic braking. Therefore, it is possible to suppress the speed increase of the car (5) during pressure oil recirculation until the electromagnetic switching valve (11) closes.

[0032] In addition, normally closed contact (30X) and resistor (24)
By arbitrarily setting the connection point with the resistor (24) and changing the short circuit amount of the resistor (24), the amount of dynamic braking, that is, the speed increase of the car (5) can be increased or decreased as necessary. Furthermore, in this case, the braking resistor (24) is installed not on the three-phase AC side of the synchronous motor (100) but on the DC circuit side of the inverter circuit (20), which complicates the configuration. There isn't.

In the above embodiment, pressure oil (3) was used as the car driving fluid, but other fluids may also be used. Further, although a normally closed contact (30X) is used as a switch means for short-circuiting the braking resistor (24) in an emergency, other switch means may be used.

[0034]

As described above, according to the present invention, a synchronous motor is used for car lifting control, and a series circuit consisting of a resistor and a switch means is inserted between the input terminals of the synchronous motor.
At the time of emergency stop of the car, the switch means is short-circuited and the synchronous motor is dynamically braked via the resistor, so that the effect of obtaining a fluid pressure elevator control device that can suppress the speed increase of the car at the time of emergency stop is achieved. be.

[Brief explanation of the drawing]

FIG. 1 is a configuration diagram showing an embodiment of the present invention.

FIG. 2 is a configuration diagram showing a conventional hydraulic elevator control device.

FIG. 3 is a side view showing the structure of the elevator drive section in FIG. 3;

FIG. 4 is a wiring diagram showing a peripheral circuit of a conventional operating contactor.

FIG. 5 is a block diagram showing a conventional speed control device.

FIG. 6 is a pattern waveform diagram for explaining the operation of a conventional hydraulic elevator control device.

FIG. 7 is a side view showing the structure of a conventional submerged elevator drive unit.

[Explanation of symbols]

(3) Pressure oil (5) Elevator car (20) Inverter circuit (24) Resistor (24a) Normally closed contact of operating contactor (switch means) (25) Speed control device (100) Synchronous motor

Claims (1)

[Claims] 1. A synchronous motor for controlling the elevation and descent of an elevator car based on the flow rate of fluid, an inverter circuit for determining the rotation speed of the synchronous motor by VVVF, a speed control device for controlling the inverter circuit, and a speed control device for controlling the inverter circuit. A fluid comprising a resistor inserted between input terminals of a synchronous motor and a series circuit consisting of a switch means, wherein the switch means is short-circuited during an emergency stop of the elevator car to dynamically brake the synchronous motor. Pressure elevator control device.