Electricity: motor control systems – Closed loop acceleration control system for dc motor with... – Armature control
Patent
1992-02-06
1993-11-09
Shoop, Jr., William M.
Electricity: motor control systems
Closed loop acceleration control system for dc motor with...
Armature control
388930, 318651, H02P 104
Patent
active
052610268
DESCRIPTION:
BRIEF SUMMARY
TECHNICAL FIELD OF THE INVENTION
This invention relates to a controlling apparatus for use in a balanced work or cargo handling system adapted to create a balanced condition between a work or cargo suspended by a driver means and a work lifting means of a work handling system by generating a force corresponding to the load or weight of the work in the driver means so that the work can be raised or lowered freely by an operator by applying a weak manual force by his, and more particularly to a controlling apparatus for use in a balanced work or cargo handling system adapted to accurately detect the weight of a work even when a drift occurs in an acceleration detector due to changes in ambient temperature etc., and therefore enable stable work raising and lowering operations to be achieved.
BACKGROUND ART OF THE INVENTION
The prior art methods and apparatuses for controlling balanced cargo or work handling systems of the kind specified above are disclosed in the publications of Japanese Laid-Open Patent Application Nos. SHO 63-196495, SHO 63-315497, HEI 1-127600 and HEI 1-133900 filed by the applicant (assignee) of the present invention.
However, the prior art controlling apparatuses for use in balanced cargo or work handling systems disclosed in the above-mentioned applications are not provided with an arithmetic unit adapted to correct fluctuations in the acceleration detection signal sent out by an acceleration detector unit.
These prior art controlling apparatuses for use in balanced cargo or work handling system have been disadvantageous in that it cannot detect the load or weight of a work or cargo accurately in case a drift occurs in the acceleration detector due to changes in the ambient temperature, etc, and also in case a negative feedback of the acceleration is made during raising and lowering of the work or cargo, the above-mentioned drift renders it impossible to conduct a stable cargo or work handling operation.
SUMMARY OF THE INVENTION
The present invention has been made in view of the above-mentioned circumstances in the prior art, and has for its object to provide a controlling apparatus for use in a balanced work or cargo handling system, which is capable of detecting the load or weight of a work even when a drift occurs in an acceleration detector due to changes in the ambient temperature, etc, and cancelling the influence of the drift even in case of negative acceleration signal feedback during the raising or lowering of the work, to thereby enable stable work raising/lowering operation to be achieved.
To achieve the above-mentioned object, according to a first aspect of the present invention, there is provided a controlling apparatus for use in a balanced work handling system, comprising: a work lifting means for raising and lowering a work suspended thereby; a driver means for driving the work lifting means; a speed detector means for detecting the rotational speed of the driver means; a position detector means for detecting the position of the work lifting means; a load detector means for detecting the loading applied to the work; a speed command instructing means for outputting a speed command signal in response to the amount of manipulation of an operating lever by an operator; an acceleration detector means for detecting the acceleration exerted on the work; a weight storage and arithmetic means for storing and computing the weight of the work in accordance with a signal transmitted by the load detector means; a command arithmetic unit for computing a command signal to be outputted to the driver means in accordance with an output signal transmitted by each of the above means, and an acceleration correcting arithmetic means adapted to output the difference between an averaged signal obtained by averaging the drifted acceleration signals transmitted by the acceleration detector means during a predetermined period of time and the drifted acceleration signal as a corrected acceleration signal to the command arithmetic unit and the weight storage and arithmetic means, respectively
REFERENCES:
patent: 4520906 (1985-06-01), Watanabe
patent: 4554999 (1985-11-01), Kamaike
patent: 4580084 (1986-04-01), Takahashi et al.
patent: 4651073 (1987-03-01), Shimizu et al.
patent: 4803409 (1989-02-01), Horikawa
patent: 4808895 (1989-02-01), Fujita et al.
Patent Abstracts of Japan, vol. 014, No. 196 (M-0964) Apr. 20, 1990 and JP-A-2 038 297 (Komatsu) Feb. 7, 1990.
Patent Abstracts of Japan, vol. 014, No. 384 (M-1013 Aug. 20, 1990 and JP-A-2 144 400 (Komatsu) Jun. 4, 1990.
Kamata Seiji
Takeda Shuu
Tomaru Hitoshi
Kabushiki Kaisha Komatsu Seisakusho
Kananen Ronald P.
Martin D.
Shoop Jr. William M.
LandOfFree
Controlling apparatus for balanced cargo or work handling system does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Controlling apparatus for balanced cargo or work handling system, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Controlling apparatus for balanced cargo or work handling system will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1149110