Elevator – industrial lift truck – or stationary lift for vehicle – Having specific load support drive-means or its control – Includes control for power source of drive-means
Reexamination Certificate
1998-12-21
2001-03-13
Salata, Jonathan (Department: 2837)
Elevator, industrial lift truck, or stationary lift for vehicle
Having specific load support drive-means or its control
Includes control for power source of drive-means
C187S290000
Reexamination Certificate
active
06199667
ABSTRACT:
BACKGROUND OF THE INVENTION
The present invention relates generally to elevator control systems and, in particular, to an apparatus and method for controlling an elevator in an energy conservation mode of operation.
In the past, elevators were adjusted to their maximum performance parameters, thus providing the most service during heavy usage periods. Unfortunately, the elevators ran with this level of performance all the time, regardless of the building needs.
In the U.S. Pat. No. 3,891,064, there is shown an elevator system that automatically switches between rated maximum performance and a reduced performance according to traffic conditions. The system normally operates at the rated maximum velocity and acceleration mode. When the demand for elevator service falls below a predetermined level, the velocity and/or the acceleration is reduced. The system includes a plurality of “traffic sensors” each of which causes switching from the reduced performance mode to the rated maximum performance mode when a predetermined traffic condition is sensed. The “traffic sensors” can include a clock that controls the switching according to traffic history.
SUMMARY OF THE INVENTION
The present invention concerns an apparatus and method for controlling an elevator system having an elevator car mounted for movement in an elevator shaft of a building, a drive coupled to the elevator car for moving the elevator car to serve floors in the building and a plurality of hall call devices located at floors served by the elevator car for generating hall call signals in response to actuation by persons at the floors to be served by the elevator car. The apparatus includes a control means for generating a velocity pattern signal the control means storing parameter values representing desired jerk, acceleration and constant speed relative to time for the velocity pattern signal and generating the velocity pattern signal in response to each hall call signal generated by the hall call devices. The drive means responds to the velocity pattern signal to move the elevator car to the floor associated with each hall call signal. The control means generates a high performance velocity pattern signal from a first set of the parameter values in response to a first predetermined number of the hall call signals in a predetermined time period and generates an energy conservation velocity pattern signal from a second set of the parameter values in response to a second predetermined number of the hall call signals in the predetermined time period. The apparatus also includes an input device connected to the control means for generating input signals representing values of the parameters whereby a user can change at least one of the stored parameter values in each of the first and second sets of the parameter values thereby altering the high performance velocity pattern signal and the energy conservation velocity pattern signal.
The control means responds to a high performance set signal generated by the input means to continuously generate the high performance velocity pattern signal and responds to an energy conservation performance set signal generated by the input means to continuously generate the energy conservation performance velocity pattern signal. Further, the control means responds to time and day set signals generated by the input means to generate the energy conservation performance velocity pattern signal during selected times on selected days of the week. The control means delays switching from generating the high performance velocity pattern signal to generating the energy conservation performance velocity pattern signal until the high performance velocity pattern signal has been generated for a minimum predetermined time period.
The method of controlling an elevator system includes the steps of: a.) selectively operating an elevator control system in a high performance mode to move an elevator car to serve hall calls at floors in a building; b.) selectively operating the elevator control system in an energy conservation performance mode to move the elevator car to serve the hall calls; c.) selectively operating the elevator control system in a time and day performance mode including operating according to the step b. during selected time periods on selected days of the week and operating according to the step a. during all other times; and d.) when operation according to all of the steps a., b. and c. is not selected, operating the elevator control system in a dynamic mode including operating according to the step a in response to a generation of at least a predetermined number of the hall calls over a predetermined time period and operating the elevator control system according to the step b. in response to a generation of less than the predetermined number of hall calls over the predetermined time period. The high performance mode includes moving the elevator car at rated values of jerk, acceleration and constant speed and the energy conservation performance mode includes moving the elevator car at less than rated values of jerk and acceleration.
The step b. includes operating the elevator control system in an energy conservation performance mode to move the elevator car to serve the hall calls when there is a power failure and emergency power is required to move the elevator car. The step d. includes delaying switching from the high performance mode to the energy conservation mode until the elevator control system has been operated in the high performance mode for a minimum predetermined time period such as approximately three minutes. The step d. also includes switching from the energy conservation mode to the high performance mode when a hall call has been waiting to be served for a maximum predetermined time period such as approximately two minutes.
One or more sensors can be connected to an input of the control means to generate signals representing conditions that may require a change in the velocity pattern. For example, a wind speed sensor can be utilized to cause the control means to reduce the maximum constant speed to a lower constant speed. An emergency power sensor can be utilized to cause the control means to reduce the startup portion of the velocity pattern to reduce the acceleration phase of the pattern.
It is an object of the present invention to provide significant energy savings and reduction on the wear and tear on the elevator equipment without compromising the service in the building.
REFERENCES:
patent: 3891064 (1975-06-01), Clark
patent: 4349087 (1982-09-01), Bittar et al.
patent: 4548299 (1985-10-01), Nomura
patent: 4640389 (1987-02-01), Kamike
patent: 5042621 (1991-08-01), Ovaska et al.
patent: 5070290 (1991-12-01), Iwasa et al.
patent: 5159163 (1992-10-01), Bahjat et al.
patent: 5241141 (1993-08-01), Cominelli
patent: 5241142 (1993-08-01), Thangavelu
patent: 5266757 (1993-11-01), Krapek et al.
patent: 5290976 (1994-03-01), Bahjat et al.
patent: 5298695 (1994-03-01), Bahjat et al.
patent: 5307903 (1994-05-01), Morita et al.
patent: 5896948 (1999-04-01), Suur-Askola et al.
Cruz Jorge
Fischgold Carmen R.
Inventio AG
MacMillan Sobanski & Todd LLC
Salata Jonathan
LandOfFree
Method and apparatus for operating an elevator drive in... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method and apparatus for operating an elevator drive in..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method and apparatus for operating an elevator drive in... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2502870