Automatically length adjustable water ski tow rope

• US 5,906,170 A
• Filed: 03/11/1998
• Issued: 05/25/1999
• Est. Priority Date: 03/11/1998
• Status: Expired due to Fees

• Current Assignee: Robertson G. David
• Original Assignee: Robertson G. David
• Inventors: Robertson, G. David
• Primary Examiner(s): Sotelo, Jesus D.
• Application Number:
  US09/046,844
• Time in Patent Office: 440 Days
• Field of Search: 114/253, 114/254, 114/294, 242/370, 242/388, 242/397, 242/570, 242/590, 242/600, 242/615
• US Class Current: 114/254
• CPC Class Codes: B63B 34/67 Connection means on the towing watercraft, e.g. pylons, side poles or winches

Abstract

Water skiers towed behind a boat can be towed by varying lengths of rope automatically adjusted by letting out or reeling in the rope to provide different lengths. The rope, trailable aft of the boat having a first boat-connecting end and a second terminal handle end has at least one length indicator placed on the rope between the first boat connecting end and the second terminal handle end. The rope is connected to a winching means mounted on said boat attached to the first boat-connecting end. A switching means allows an occupant of the boat to actuate the winching means as the boat moves through the water. A sensing means senses the passage of the length indicator on the rope, and provides a signal to the winching means upon sensing the length indicator. This signal stops the winching means, disposing the sensing means within ten centimeters of the length indicator, thereby providing at least two precisely predetermined lengths of rope trailable aft of the boat.

Claims

1. A water ski tow rope apparatus comprising:

a boat;

a rope trailable aft of the boat having a first boat-connecting end and a second terminal handle end;

at least one contrasting color length indicator placed on the rope between the first boat connecting end and the second terminal handle end;

winching means mounted on said boat attached to the first boat-connecting end;

activating means allowing an occupant of the boat to actuate the winching means as the boat moves through the water; and

photocell means to sense the contrasting color length indicator on the rope, the sensing means providing a signal to the winching means upon sensing the length indicator, the signal stopping the winching means, disposing the sensing means within ten centimeters of the length indicator, thereby providing at least two precisely predetermined lengths of rope trailable aft of the boat.

2. The water ski tow rope apparatus of claim 1 wherein the water ski tow rope apparatus further comprises more than one indicia placed on the rope at predetermined intervals.

3. The water ski tow rope apparatus of claim 1 wherein the apparatus further includes a central mounting stand to hold the rope fast to the boat.

4. The water ski tow rope apparatus of claim 3 wherein the apparatus further includes a redirecting means on the central mounting stand to redirect the rope from a winch means mounted on the boat below the central mounting stand to the top of the stand and there to the towed water skier.

5. The water ski tow rope apparatus of claim 1 further including on the tow rope contrasting color indicator means and on the sensing means a means to detect variations in the amount of light reflected from the rope.

6. The water ski tow rope apparatus of claim 5 further including a photoelectric cell to measure the variation in the amount of light reflected.

7. The water ski tow rope apparatus of claim 1 further including a magnetic means.

8. The water ski tow rope apparatus of claim 1 further including on the tow rope contrasting color indicator means and on the sensing means a means to detect variations in the amount of light reflected from the rope and a photoelectric cell to measure the variation in the amount of light reflected.

9. The water ski tow rope apparatus of claim 1 further including a two-way switching means to take in and play out rope.

10. The water ski tow rope apparatus of claim 9 wherein the indicator further comprises a plug of non-corrosive material interweaved with the strands of the rope.

11. A water ski tow rope comprising;

a substantially non-stretchable rope having a first end suitable for attachment to a boat and a second end having handle means; and

at least one indicator of length incorporated on the rope.

12. The water ski tow rope of claim 11 wherein the sensing means further comprises a first jaw member and a second jaw member movable relative to the first jaw member that opens when the portion of larger diameter forces the first member away from the second member, the movement throwing an electric switch.

13. The water ski tow rope of claim 11 further including magnetic means.

14. The water ski tow rope of claim 11 wherein the length indicator is a portion of the rope having a larger diameter than the rest of the rope.

15. The water ski tow rope of claim 11 wherein the indicator further comprises a plug of non-corrosive material interweaved with the strands of the rope.

16. A water ski tow rope apparatus comprising:

a boat;

a rope trailable aft of the boat having a first boat-connecting end and a second terminal handle end;

the rope having a portion of larger diameter having interwoven with the strands at least one plug of non-corrosive material placed on the rope between the first boat connecting end and the second terminal handle end;

winching means mounted on said boat attached to the first boat-connecting end;

activating means allowing an occupant of the boat to actuate the winching means as the boat moves through the water; and

a means to detect the plug having a first jaw member and a second jaw member movable relative to the first jaws member that opens when the portion of larger diameter forces the first member away from the second member, the movement throwing an electric switch, to provide a signal to the winching means upon sensing the length indicator, the signal stopping the winching means, disposing the sensing means within ten centimeters of the length indicator, thereby providing at least two precisely predetermined lengths of rope trailable aft of the boat.

17. The water ski tow rope apparatus of claim 16 wherein the length indicator is a portion of the rope having a larger diameter than the rest of the rope, the indicator further comprises a plug of non-corrosive material interweaved with the strands of the rope and the sensing means further comprises a first jaw member and a second jaw member movable relative to the first jaw member that opens when the portion of larger diameter forces the first member away from the second member, the movement throwing an electric switch.