JPH06127852A - Elevator start control method - Google Patents

Abstract

PURPOSE:To perform smooth start regardless of whether an induction motor is driven from the hoisting machine side or not after the release of a brake. CONSTITUTION:An elevator system is provided with a hoisting machine 8 for driving a car 7, an induction motor 3 for driving the hoisting machine 8, a brake 6 for braking the hoisting machine 8, and a pulse signal generator 4 direct-coupled to an inverter device 2 and the induction motor 3. In such an elevator system, the inverter is started before the release of the brake 6 to make the induction motor 3 only excited, and then if the induction motor 3 is at a stop without being driven from the hoisting machine 8 side after the release of the brake 6, only the exciting action of the induction motor 3 is performed. In the case of the induction motor 3 being driven from the hoisting machine 8 side and rotated, normal operation is started after zero speed control.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a technique for realizing a good riding comfort in an elevator system using an induction motor driven by an inverter as a hoisting motor.

[0002]

2. Description of the Related Art A conventional elevator driving method will be described with reference to an example of a conventional elevator drive system shown in FIG.

In a conventional elevator control method, when a call is received from the floor, the elevator control device 1 issues an operation command to the inverter device 2, releases the brake 6, and the pulse signal generator 4 mounted on the induction motor 3. Signal from
The control arithmetic unit 16 in the inverter unit 2 receives and sends a signal to the driver 15 by a predetermined arithmetic operation to turn on / off the switching element to drive the induction motor 3 so that the induction motor 3 rotates in a predetermined speed pattern, Ring 5
The hoisting machine 8 is driven via the. The sheave 9 attached to the hoisting machine 8 rotates, and the car 7 and the counterweight 10 connected by the rope 14 attached to the sheave are driven up and down.

At the time of starting such an elevator,
The time from the time when the elevator start signal is input to the time when the brake that holds the car is released is the same as the time when the elevator start signal is input until the speed of the induction motor is controlled by the inverter. There is a method of adjusting with the external timer 17.

[0005]

In the conventional elevator start-up control method, the time from the time when the elevator start-up signal is input to the time when the brake 6 holding the car 7 is released changes due to environmental changes or the like. Depending on the factor, the inverter device 2 starts from the time when the elevator start signal is input.
When the induction motor 3 becomes longer than the time it takes to drive the induction motor 3 in the speed pattern of the elevator by the driver 15, unnecessary torque is output when the brake 6 is turned on. If the brake 6 is released in the state of being balanced, the torque is generated for a moment more than necessary even if almost no torque is required, and the torque is immediately reduced. I was feeling uncomfortable.

Further, when the brake release time is short and the counterweight 10 and the car 7 are unbalanced, the induction motor 3 is driven from the hoisting machine 8 side, so that a rapid change in the torque holding the induction motor 3 causes an elevator. Was deteriorating the comfort of starting.

According to the present invention, after the brake is released, if the induction motor 3 is not driven by the hoisting machine 8 and is stopped, only the exciting action of the induction motor is performed, and the induction motor 3 is driven from the hoisting machine 8 side. When the vehicle is rotated, the zero speed control is performed to stabilize and improve the riding comfort when the elevator is started.

[0008]

In order to achieve the above object, in the elevator start control method according to the present invention, after the inverter is started before the brake is released and only the exciting action of the induction motor is performed, After releasing the brake, if the induction motor is not driven by the hoisting machine side and is stopped, only the exciting action of the induction motor is performed, and if the induction motor is driven by the hoisting machine side and rotates, zero speed control is performed. After that, it is characterized by entering a normal driving state.

That is, the induction motor is provided with a pulse generator, the inverter device for driving the induction motor is provided with a counter for counting the output pulses of the pulse generator, and software for controlling using the counter is provided. As the block, a block for zero speed control and a block for excitation function are provided.

[0010]

In the elevator system configured as described above, when a start signal is input to the inverter device from the elevator control device, the inverter device first only excites the induction motor. The inverter device outputs a brake release signal to the elevator controller, and the elevator controller releases the brake. If the car and counterweight are in equilibrium, the sheave will not rotate even if the brake is released,
Therefore, the induction motor does not rotate. That is, no pulse signal is generated from the pulse signal generator, and the value of the counter of the inverter device becomes almost zero. At this time, the inverter device only excites the induction motor. When the car and the counterweight are unbalanced, the sheave rotates when the brake is released, and the induction motor is driven to rotate. That is, a pulse signal is generated from the pulse signal generator, and the counter of the inverter device counts the pulse signal. At this time, the inverter device controls the induction motor at zero speed. In either case, the car remains stopped for a predetermined time, and after an appropriate time has elapsed, the inverter device starts operation according to a regular speed pattern.

[0011]

FIG. 1 shows an embodiment of a method for starting an elevator according to the present invention. The mechanical part is the same as the conventional device shown in FIG. That is, the brake 6 is connected to the induction motor 3 to which the pulse signal generator 4 is attached via the coupling 5.
The hoisting machine 8 is provided after the brake 6. The hoisting machine 8 is provided with a sheave 9, a rope 14 is hung on the sheave 9, and a car 7 and a counterweight 10 are attached to both ends thereof.

In the elevator start control method according to the present invention, the counter 13 for counting the output pulses of the pulse signal generator 4 in the inverter 2 for driving the induction motor 3 is used.
Further, as a software block for performing control using the counter 13, a zero speed control block 12 and a block 11 for performing an exciting action are provided in the control arithmetic unit 16 in the inverter device. A switch for switching between the two blocks by a signal from the counter 13 is provided.

In such an elevator system,
When a start signal is input from the elevator control device 1 to the inverter device 2, first, the driver 13 excites the induction motor 3 by a signal from the block 11 that excites. At this time, the control arithmetic unit 16 outputs a brake release signal to the elevator control unit 1, and the elevator control unit 1 releases the brake 6.

If the car 7 and the counterweight 10 are balanced, the sheave 9 will not rotate even if the brake 6 is released,
The induction motor also does not rotate. That is, no pulse signal is generated from the pulse signal generator 4, and the value of the counter 13 in the inverter device 2 remains substantially zero. At this time, the counter
A block 13 operates a block 11 that performs an exciting action via a switch, and the inverter device 2 only performs an exciting action on the induction motor 3.

When the car 7 and the counterweight 10 are unbalanced, when the brake 6 is released, the sheave 9 rotates,
The hoisting machine 8 drives the induction motor 3, the pulse signal is generated from the pulse signal generator 4, and the inverter device 2
Counter 13 counts the pulse signal. At this time, the counter 13 operates the zero speed control block 12 via the switch, and the inverter device 2 performs the zero speed control on the induction motor 3.

Thus, in the elevator starting control method according to the present invention, the induction motor 3 remains stopped regardless of whether the car 7 and the counterweight 10 are balanced or unbalanced even after the brake 6 is opened. In this state, after an appropriate time has passed, the inverter device 2 will be set in both blocks 11 and 12
The operation is started according to the regular speed pattern, apart from the influence of.

[0017]

According to the elevator start control method of the present invention, the following effects can be obtained by the above configuration.

First, by generating the speed pulse of the elevator at the time when the brake 6 is always released, it is possible to prevent the torque of the induction motor 3 from being generated when the brake is applied.

Second, since the induction motor 3 is controlled at zero speed by generating the speed pulse of the elevator when driven from the hoisting machine side 8, the induction motor 3 is stopped even if the brake 6 is opened. The sheave 9 or the car 7 remains stationary.

Thirdly, the time to release the brake 6 may be set to the time when the elevator control device 1 receives the brake release signal output from the inverter device 2, and the adjustment of the brake release time is unnecessary. Stable and good ride comfort is obtained at startup.

[Brief description of drawings]

FIG. 1 is a diagram showing an embodiment of a method for starting an elevator according to the present invention.

FIG. 2 is a diagram showing an example of a conventional elevator drive system.

[Explanation of symbols]

 1 Elevator control device 2 Inverter device 3 Induction motor 4 Pulse signal generator 5 Coupling 6 Brake 7 Car 8 Hoisting machine 9 Sieve 10 Counterweight 11 Block for performing excitation 12 Block for zero speed control 13 Counter 14 Rope 15 Driver 16 Control arithmetic unit

Claims (1)

[Claims] 1. An elevator system comprising a hoisting machine for driving a car, an induction motor for driving the hoisting machine, a brake for braking, an inverter device and a pulse signal generator directly connected to the induction motor, After starting the inverter before releasing the brake and performing only the exciting action of the induction motor, after the brake is released, if the induction motor is not driven from the hoisting machine side and stopped, only the exciting action of the induction motor is performed, When the induction motor is driven from the hoisting machine side and rotates, zero-speed control is performed, and then a normal operating state is entered, which is a method for controlling startup of an elevator.