IP Library Granted Patent US 7,931,128
Granted Patent B2
US 7,931,128 · App. 11/666,989 · Granted Apr 26, 2011

Elevator device

Assignee: Mitsubishi Electric Corporation
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Quick Facts
Patent No.
US 7,931,128
App. No.
11/666,989
Granted
Apr 26, 2011
Kind
B2
Abstract

In an elevator device, a drive unit has a drive sheave, a motor for rotating the drive sheave, and a motor driving portion for driving the motor. The motor driving portion is controlled by a control unit. When a car is running, the control unit monitors a load on at least one component within the drive unit, and generates a control command regarding a running speed of the car in accordance with a state of the load, and outputs the control command to the motor driving portion.

Claims (40)

1. An elevator device, comprising:

drive means including a drive sheave, a motor for rotating the drive sheave, and a motor driving portion for driving the motor;

suspension means looped around the drive sheave;

a car and a counterweight that are suspended by the suspension means to be raised/lowered by the drive means; and

control means for controlling the motor driving portion,

wherein the control means monitors a load on at least one component of the drive sheave, the motor for rotating the drive sheave, and the motor driving portion for driving the motor within the drive means, by monitoring at least one of a current, a temperature, a power, a switching duty, or a motor voltage of the at least one component while that at least one component is operating and while the car is running, generates a control command regarding a running speed of the car on a real-time basis in accordance with a state of the load, and outputs the control command to the motor driving portion,

wherein (i) the control means continuously raises the running speed of the car after the car has started running, until the running speed of the car reaches an upper limit that is prescribed when the car starts running, and holds the running speed of the car at the upper limit to make a shift to constant-speed running unless the load monitored while the at least one component is operating and while the car is running reaches a preset threshold, and (ii) when the load monitored while the at least one component is operating and while the car is running reaches the preset threshold before the running speed of the car reaches the upper limit, the control means shifts to a constant-speed running at a speed lower than the upper limit.

2. The elevator device according to claim 1 , wherein the control means continuously raises the running speed of the car after the car has started running, and reduces an acceleration of the car when the load reaches the threshold.

3. The elevator device according to claim 2 , wherein the control means raises the acceleration of the car until the acceleration of the car reaches a predetermined acceleration after the car has started running.

4. The elevator device according to claim 1 , wherein, when the load reaches the threshold during accelerated running of the car, the control means generates the control command such that the car is allowed to run at a constant speed.

5. The elevator device according to claim 1 , wherein, when the load reaches the threshold during accelerated running of the car, the control means generates the control command such that the load is held at the preset threshold.

6. The elevator device according to claim 1 , wherein the control means monitors at least one of a current, a voltage, and a temperature of the motor as the load.

7. The elevator device according to claim 1 , wherein;

the motor driving portion comprises an inverter; and

the control means monitors at least one of a current, a temperature, a switching duty, and a voltage of the inverter as the load.

8. The elevator device according to claim 1 , wherein the control means converts a current supplied to the motor into a d-axis current and a q-axis current in a Cartesian coordinate system, and monitors at least one of the d-axis current and the q-axis current as the load.

9. The elevator device according to claim 1 , wherein:

the motor driving portion comprises an inverter; and

the control means generates a d-axis current command and a q-axis current command in a Cartesian coordinate system to control the inverter, and monitors at least one of the d-axis current command and the q-axis current command as the load.

10. The elevator device according to claim 1 , wherein:

the motor driving portion comprises an inverter; and

the control means monitors a power supplied from the inverter to the motor as the load.

11. The elevator device according to claim 1 , wherein:

the motor driving portion comprises a regenerative resistor; and

the control means monitors a temperature of the regenerative resistor as the load.

12. The elevator device according to claim 1 , wherein:

the motor driving portion comprises a regenerative resistor, and

the control means monitors a regenerative power obtained through the regenerative resistor as the load.

13. The elevator device according to claim 1 , wherein:

the motor driving portion comprises an inverter, and a breaker connected between the inverter and a power supply; and

the control means monitors a current flowing through the breaker as the load.

14. The elevator device according to claim 1 , wherein:

the motor driving portion comprises an inverter, and a converter connected between the inverter and a power supply; and

the control means monitors a DC voltage input from the converter to the inverter.

15. The elevator device according to claim 1 , wherein:

the motor driving portion comprises an inverter; and

the control means comprising a current control portion for generating a current command to control the inverter, compares a current supplied from the inverter to the motor with the current command to indirectly monitor the load.

16. The elevator device according to claim 1 , wherein:

the drive means is provided with a speed detector for detecting a rotational speed of the motor; and

the control means comprising a speed command generating portion for generating a speed command as the control command regarding the rotational speed of the motor, compares the speed detected by the speed detector with the speed command to indirectlyonitor the load.

Assignments (2)
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Jul 29, 2020
From: MITSUBISHI ELECTRIC CORPORATION
To: MUROLET IP LLC
Reel/Frame 053343/0443 →
CORRECTIVE ASSIGNMENT TO CORRECT THE SERIAL NUMBER PREVIOUSLY RECORDED ON REEL 020175 FRAME 0070. ASSIGNOR(S) HEREBY CONFIRMS THE ASSIGNMENT. Recorded Dec 10, 2007
From: SAKAI, MASAYA; UEDA, TAKAHARU
To: MITSUBISHI ELECTRIC CORPORATION
Reel/Frame 020221/0688 →
Priority Claims (1)
JP PCT/JP2005/013640 · Jul 26, 2005 · national
Continuity (1)
Related Publication 20070284196A1 · Dec 13, 2007