Implements or apparatus for applying pushing or pulling force – Apparatus for hauling or hoisting load – including driven... – Device includes rotatably driven – cable contacting drum
Patent
1996-06-28
1998-04-07
Matecki, Katherine
Implements or apparatus for applying pushing or pulling force
Apparatus for hauling or hoisting load, including driven...
Device includes rotatably driven, cable contacting drum
254377, B66D 108
Patent
active
057355061
DESCRIPTION:
BRIEF SUMMARY
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to winches which are moved by a hydraulic motor. It applies more particularly to winches equipping helicopters and which especially allow there to be immersed in the sea a sonar known as a "dipping sonar" which is suspended from the end of the cable of the winch so that it can be brought back on board the helicopter afterwards.
2. Discussion of the Background
Helicopters are often equipped with a winch which allows loads to be set down and picked back up in places which are difficult to access, by making the helicopter hover.
In the case of helicopters specialized for submarine hunting, use is made of a very specific winch which, with the aid of an electric supporting cable, allows a specialized sonar to be immersed for detecting the presence of a submarine, and allows this sonar to be recovered in order to go and take measurements a little further on.
Such a mission imposes particularly severe stresses on the device employed. Indeed it is necessary to be able to lower and to raise the sonar with a high average speed, typically 5 m per second, while protecting the cable which is relatively fragile in order to avoid loss of the sonar. Furthermore, it is also necessary to ensure the safety of the helicopter by avoiding sharp and excessive forces at the winch by avoiding the overheating of the oil of the hydraulic circuit, because the volume of hydraulic fluid is low for reasons of weight and there is therefore the risk of its temperature rising rapidly and exceeding the safety temperatures. These constraints have to be respected while at the same time maintaining good reliability and nevertheless keeping down the cost of the device.
Winches are known which are designed so that descent takes place by free fall by mechanically disengaging the motor from the drum on which the cable is wound. This method is clearly dangerous.
The winches most commonly used at the present time include a hydraulic motor which both allows the sonar to be raised back up and allows its descent to be controlled. Such a winch assembly has been represented diagrammatically in FIG. 1.
In this winch, a hydraulic motor 101 drives a worm 102 which itself drives a wheel 103 keyed to the shaft 111 of the drum on which the cable is wound and unwound. This worm system makes it possible in a simple and reliable manner to obtain the desired reduction ratio. It does, however, have the drawback of having a low efficiency, some 40%, in the reverse direction. In this mode of operation, that is to say when the load on the cable is driving the hydraulic motor when this load is descending, this low efficiency here is of little inconvenience bearing in mind the control circuits used, represented diagrammatically by the hydraulic control unit 104.
Furthermore, use is made of a brake 105 actuated by the hydraulic energy of the unit 104 or with the aid of a control lever 106. This brake allows the winch to be immobilized in periods when it is not operating.
Finally, in order for it to be possible for the winch to be operated even if the hydraulic system breaks down, an electric motor 107 is provided which drives the worm 102 by means of a reduction gear 108 and a dog clutch 109. This dog clutch is engaged mechanically by a second control lever 110 which furthermore mechanically controls a discharge valve situated in the hydraulic unit 104, which allows the hydraulic motor 101 to rotate freely in such cases.
FIG. 2 represents the mechanical part of FIG. 1, simplified, and the hydraulic unit 104 in greater detail.
The load 201 on the winch is fastened to the end of a cable 202 which is wound on a drum 203. This drum 203 is driven by the hydraulic motor 101 itself released, or immobilized, as the case may be, by a brake 105.
The motor 101 is fed from a source of hydraulic fluid under pressure P by means of a shut-off valve 204 and of a 4-way servo-valve 205. The shut-off valve makes it possible to apply all of the pressure to the servo-valve under the control of a pilot electr
REFERENCES:
patent: 3035414 (1962-05-01), Smith
patent: 3780990 (1973-12-01), Edlund et al.
patent: 4004779 (1977-01-01), Flesburg
patent: 4188790 (1980-02-01), Pedersen
patent: 4275870 (1981-06-01), Henneman et al.
patent: 4555092 (1985-11-01), Overholt
patent: 4861297 (1989-08-01), Warnan
patent: 4954110 (1990-09-01), Warnan
patent: 4991534 (1991-02-01), Warnan et al.
patent: 5014953 (1991-05-01), Warnan et al.
patent: 5044160 (1991-09-01), Warnan et al.
patent: 5091894 (1992-02-01), Warnan
patent: 5381909 (1995-01-01), Warnan
Canto Daniel
Warnan Fran.cedilla.ois
"Thomson-CSF"
Matecki Katherine
LandOfFree
Winch with hydraulic motor especially for helicopter equipped wi does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Winch with hydraulic motor especially for helicopter equipped wi, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Winch with hydraulic motor especially for helicopter equipped wi will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-6455