Abstract:
A remote controlled boat lift comprises a remote transmitter unit that can selectively transmit one of two pre-determined RF signals, an up receiver and down receiver connected to operate a pressure pump system and valves for selectively inflating and deflating a pontoon supported framework for docking a boat.

Description:
BACKGROUND AND SUMMARY OF THE INVENTION 
     Many boat owners have pontoon type boat lifts in their docks which can be inflated to raise their boat out of the water when not in use to eliminate the problems associated with storing a boat floating in the water. A typical boat lift is shown in U.S. Pat. No. 4,072,119, entitled &#34;VERTICAL RISING BOAT LIFT&#34;, issued Feb. 7, 1978. These prior art boat lifts are generally controlled by a manual control mounted on the dock which requires someone on the dock to operate the lift while the boat is docking or undocking. If the boat is undocking, it is necessary for the lift to first be deflated to permit the boat to be floated out of the lift, and then re-inflated to prevent damage to the lift. After re-inflation, the boat has to return to the side of the dock to pick up the person who remained there to manually operate the on-dock control. Of course, the process must be reversed to dock the boat. This procedure is an inconvenience and entails some danger as a passing boat could cause waves which might slam the boat against the dock or cause the person being picked up to misstep and go overboard. This procedure is also inconvenient and detracts from the enjoyment of boating. However, these lifts are generally expensive and if left in the deflated condition, they can be damaged or sunk and lost by the current, backwash or other similar water condition. Nevertheless, because of the inconvenience, many boat owners do not bother re-inflating the lift and instead take the risk of loss or damage. 
     To solve these and other problems of the prior art, the inventor herein has succeeded in developing a remote control device which enables a boat operator to raise and/or lower the boat lift while he is in the boat and not on the dock. With the present invention, an operator can lower the boat lift, board the boat, back the boat out of the dock, and then remotely raise the boat lift while he is in the boat. As can be appreciated, this permits one-man operation without leaving the controls of the boat, and also eliminates the problem of returning to the dock to pick up the lift operator or, conversely, leaving the lift submerged and susceptible to damage or loss. 
     The radio controlled boat lift of the present invention generally comprises a transmitter device capable of generating one of two pre-determined RF signals, a pair of receivers each of which is tuned to one of the transmitted RF signals, electrical control circuitry connected to the receivers and a pressure pump with valves to operate the boat lift. Additionally, manual pushbutton or lever controls can be provided as was typically utilized in the prior art to permit operation from the dock without possession of the remote control. 
     In operation, the boat lift initially is up with the boat out of the water and supported by the lift. An operator may then manually operate the lift to lower it, or alternatively utilize the remote control transmitter to lower the lift and boat down into the water. The operator and any passengers may then board the boat and the boat may be launched. After clearing the dock area and before leaving, the operator may then operate the remote transmitter to generate the first RF signal which when received by the correct receiver raises the lift out of the water to store it in a floating position. As mentioned above, this prevents damage or loss to the boat lift. 
     Upon returning, the operator then utilizes the remote transmitter to generate the other predetermined RF signal which is received by the down receiver and which deflates the lift to lower it into a submerged position. Once submerged, the boat may then be maneuvered into position in the dock and over the boat lift. The passengers and operator may then disembark, and either the remote transmitter or the local manual control may be utilized to inflate the boat lift and raise the boat out of the water for storage, as desired. 
     The remote control boat lift control of this invention provides the user with a safe, convenient, and enjoyable way to operate a boat lift while eliminating the disadvantages that are associated with manual operation. 
    
    
     BRIEF DESCRIPTION OF THE DRAWING 
     The drawing is a schematic diagram of the radio controlled boat lift control of the present invention. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     The radio controlled boat lift of this invention is indicated generally as 10 in the drawing. 
     The radio controlled boat lift control has a transmitter unit 12 which transmits one of two radio frequency signals to either an up or inflate receiver unit 14 or a down or deflate receiver unit 16. The transmitter unit 12 is enclosed in a casing and may have two buttons, an up button 11 and a down button 13. The inventor has found that a dual frequency remote control garage door opener unit may be utilized as the transmitter and receiver portions of the present invention. Upon transmitting an up signal the up receiver unit 14 will energize relay 22 and close contact 24. With contact 24 closed, voltage is supplied from the power supply 26 which then turns pressure pump 28 on. The energizing of relay 22 also closes contact 30. With contact 30 closed, voltage is supplied from the power supply 26 to open the up or inflate valve 34. Therefore, the air from pump 28 flows through valve 34 to inflate pontoons 44, 46. A step down transformer 32 having a primary winding 31 and a secondary winding 33 is connected to the power supply 26. 
     A signal sent to the down receiver 16 will energize relay 36 and close contact 38. The closing of contact 38 will supply voltage from the power supply 26 to open the down or deflate valve 40, thereby deflating pontoons 44, 46. 
     A hose 42 connects the pressure pump 28 to each of the pontoons 44 and 46. To raise and lower the boat a frame assembly indicated generally as 48 is utilized. The frame assembly is not described in detail because its use is well known in the art of boat lifts. 
     With the radio controlled boat lift and the boat in the up position, the pontoons 44 and 46 are filled with air. When the user wishes to launch the boat, the down button 13 of the transmitter 12 is pressed and held down. Valve 40 opens, releasing air that has been stored in the pontoons causing buoyancy to be lost and the boat and frame 48 are lowered into the water. When the boat and frame have been lowered into the water, down button 13 is released and the driver and passengers may then safely board the boat. Releasing the down button 13 also causes valve 40 to close. The boat then clears the dock area and the user presses and holds down the up button 11 of the transmitter 12. Once the up button 11 is pressed and held down the pressure pump 28 is energized and valve 34 is opened. Air is forced into the pontoons 44, 46 through hose 42 and the frame 48 lifts upwardly until it is out of the water. When the frame 48 is out of the water the up button 11 is released shutting off valve 34 and pressure pump 28. If desired, timers may be substituted for relays 22, 36 and used to automatically raise or lower the lift after only an intermittent operation of buttons 11, 13. 
     Upon returning from the boating trip, the user presses and holds the down button 13 of the transmitter 12 to lower the boat lift into the water. Once the frame 48 is in the water the boat is then floated into position over the frame 48. Once the driver and passengers have safely disembarked the up button 11 of the transmitter 12 is pressed and held to lift the boat to its initial position. 
     Also, manual override switches may be provided for occasions when the user is on the dock and the transmitter 12 is not within reach. For example, manual switch 18 may be pressed to inflate the boat lift or manual switch 20 may be pressed to deflate the boat lift. 
     In addition to valves 34 and 40 there may be a manual valve 50 which allows the user to operate the boat lift manually. 
     There are various changes and modifications which may be made to this invention as would be apparent to those skilled in the art. However, these changes or modifications are included in the teaching of the disclosure, and it is intended that the invention be limited only by the scope of the claims appended hereto.