Hydrofoil cavitation sensing and control apparatus

• US 3,910,216 A
• Filed: 06/10/1974
• Issued: 10/07/1975
• Est. Priority Date: 06/10/1974
• Status: Expired due to Term

• Current Assignee: William M. Shultz
• Original Assignee: William M. Shultz
• Inventors: Shultz, William M.
• Primary Examiner(s): Blix, Trygve M.
• Assistant Examiner(s): Frankfort, Charles E.
• Application Number:
  US05/478,117
• Time in Patent Office: 484 Days
• Field of Search: 114/66.5R,66.5H 115/11,14 340/5R,8R 73/67 415/1,27 417/42
• US Class Current: 114/275
• CPC Class Codes: B63B 1/28 with movable hydrofoils

Abstract

A cavitation detection and control system for controlling the movement of a hydrofoil within a safe, cavitation-free, acceleration and speed region. The system utilizes transducers, associated with the hydrofoil propulsion apparatus and associated with the foil/strut apparatus, for sensing the onset and duration of cavitation in the liquid working medium adjacent to or within these apparatus and a receiver for converting the sensed cavitation data into a signal. An alarm device is responsive to that signal so that the helmsman can reduce the thrust for operating the hydrofoil movement within a cavitation-free region. A data storing device is connected to the receivers output for retaining occurrence of the onset and duration of cavitation.

Claims

1. System for detecting the occurrence of cavitation during the start to maximum speed of the thrust and speed operation of a hydrofoil boat employing liquid propulsion means and strut/foil means, comprising in combination:

a. first transducer means associated with said liquid propulsion means for detecting cavitation noise in said liquid of said propulsion means and for converting said cavitation noise into a first signal;

b. second transducer means associated with said hydrofoil/strut means for detecting cavitation noise about said hydrofoil/strut system ambient liquid medium and converting said cavitation noise into a second signal;

c. receiving means for sensing the presence of said first and said second signals, and for generating an output signal, and d. means connected to said receiving means and responsive to said output signal for imparting a warning to an operator of said hydrofoil boat signifying the presence of said first and said second signals.

2. A system as claimed in claim 1 wherein said first transducer means is mounted in said liquid propulsion means associated pumping system, and wherein said second transducer means is mounted to said strut/foil structural intersection.

3. A system as claimed in claim 2 wherein said means connected to said receiving means includes an alarm device to tell an associated helmsman to reduce said thrust and speed control operation.

4. A system as claimed in claim 3 wherein said means connected to said receiving means includes a recording device for retaining the output of said receiving means.

5. An apparatus for informing of cavitation development during acceleration and speed control operation of a hydrofoil boat with strut/foil means employing waterjet propulsion apparatus comprising in combination:

a. first transducer means associated with said waterjet propulsion apparatus for detecting and converting cavitation into a first signal;

b. second transducer means associated with said hydrofoil boat strut/foil means for detecting and converting cavitation into a second signal;

c. receiving means electrically connected to said first and second transducer means and adapted to sense said first and second signals at a predetermined level, and for generating an output signal, and d. means connected to said receiving means and responsive to said output signal for imparting a warning to an operator of said hydrofoil boat signifying the presence of said first and said second signals.

6. An apparatus as claimed in claim 5 wherein said first transducer means is mounted at said waterjet propulsion apparatus associated pumping means and wherein said second transducer means is mounted at said strut/foil structural intersection.

7. An apparatus as claimed in claim 5 wherein said means connected to said receiving means includes a recording device.