Trawl cable vibration meter
OwnerChristopher N. Tupper, Charles P. Saundersinventors
Life of this patent
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Abstract
A trawl cable vibration meter is described for monitoring the vibration in the trawl cables which connect a vessel and a set of trawl doors. The doors are connected to a fishing net and are towed along the ocean floor. A sensor, mounted on the vessel at a location where stress is tranferred to the vessel, provides signals corresponding to the vibration in each cable which is indicative of the interaction between the trawl door and the ocean bottom. An interface provides ongoing information on the vibration, and an alarm system for notifying an operator when a threshold has been exceeded.
Claims28
An apparatus for detecting and measuring the load vibration in port and starboard trawl cables, each of said cables connected to separate cable handling mechanisms, where load is transferred from the cables to a fishing vessel on which said mechanisms are mounted, the mechanisms supporting the entire loads from respective cables, and each of said cables attached to trawl doors which ride along the ocean floor, said trawl doors connected to a fishing net, said apparatus comprising:
- two vibration detection mechanisms, one corresponding to each trawl cable, each of said detection mechanisms mounted on the cable handling mechanism for the respective cable, each of said detection mechanisms for detecting load vibration representative of a time rate of stress change in one of said two trawl cables connected between an associated cable handling mechanism and trawl door and indicative of interaction between the trawl doors and the ocean floor, said detection mechanism generating an electrical signal corresponding to said vibration;
- and
- an operator interface connected to receive each electrical signal and to provide information to an operator regarding the vibration in each trawl cable.
An apparatus for detecting and measuring the vibration in port and starboard trawl cables, each of said cables connected to separate cable handling mechanisms mounted on a fishing vessel, and each of said cables attached to trawl doors which ride along the ocean connected to a fishing net, said apparatus comprising:
- two vibration detection mechanisms, one corresponding to each trawl cable, each of said detection mechanisms mounted on the cable handling mechanism for the respective cable, each of said detection mechanisms for detecting vibration in one of said two trawl cables indicative of interaction between the trawl doors and the ocean floor and for generating an electrical corresponding to said vibration;
- and
- an operator interface connected to receive each electrical signal and to provide information to an operator regarding the vibration in each trawl cable, said interface having two separate visible indicators, each providing information about the vibration in one of said trawl cables, wherein said two visible indicators are two light bars, one corresponding to said port trawl cable and the other corresponding to said starboard trawl cable, the lit portion of said light bars indicative of the intensity of the vibration in each cable.
An apparatus for detecting and measuring the vibration in port and starboard trawl cables, each of said cables connected to separate cable handling mechanisms mounted on a fishing vessel, and each of said cables attached to trawl doors which ride along the ocean floor and are connected to a fishing net, said apparatus comprising:
- two vibration detection mechanisms, one corresponding to each trawl cable, each of said detection mechanisms mounted on the cable handling mechanism for the respective cable, each of said detection mechanisms for detecting vibration in one of said two trawl cables indicative of interaction between the trawl doors and the ocean floor, said detection mechanism generating an electrical signal corresponding to said vibration;
- and
- an operator interface connected to receive each electrical signal and to provide information to an operator regarding the vibration in each trawl cable, said operator interface including signal processing circuitry for confining the frequencies of each signal to a range with a lower range of about 0.7 hertz and a higher range of about 20 hertz, said lower range set to filter frequencies from ocean motion.
An apparatus for detecting the load vibration in a trawl cable which is connected to a cable handling mechanism on a vessel and to a trawl door which is towed along the ocean floor, the cable handling mechanism including a trawl block mounted to the vessel, said apparatus comprising:
- a vibration detection mechanism, mounted inboard the trawl block at a location on the cable handling mechanism for measuring load vibration of the cable handling mechanism where load is transferred between said cable and said vessel, said vibration detection mechanism providing an output based on the load vibration in said trawl cable indicative of the interaction between said trawl door and said ocean floor;
- a triggering mechanism for receiving an output from said vibration detection mechanism and for comparing said output to a threshold value;
- and
- an alarm mechanism responsive to a determination that said output exceeds said threshold value.
An apparatus for detecting and measuring the load vibration in port and starboard trawl cables, each of said cables connected to separate cable handling mechanisms mounted on a fishing vessel, and each of said cables attached to trawl doors which ride along the ocean floor and are connected to a fishing net, said apparatus comprising:
- two vibration detection mechanisms, one corresponding to each trawl cable, each of said detection mechanisms mounted on the cable handling mechanism for the respective cable, each of said detection mechanisms for detecting load vibration in one of said two trawl cables indicative of interaction between the trawl doors and the ocean floor and for generating an electrical signal corresponding to said vibration;
- and
- an operator interface connected to receive each electrical signal and to provide information to an operator regarding the vibration in each trawl cable, said vibration detection mechanisms mounted to a corresponding brake lever arm of a winch assembly associated with each said cable handling mechanism where load from each cable is transferred to each said winch assembly.
Dependencies are inferred from the claim text.