Powered method and apparatus for lifting a boat

In a boat lift assembly having a mechanical boat lift with a frame, movable lifting structure in the frame for support and lifting of a boat in the lift, a drive mechanism between the frame and the lifting structure, and a manually operable actuator wheel of at least two feet in diameter connected to the mechanism;

• the improvement of an electrical power boat lift actuator wheel drive comprising
• (a) a tractive drive unit having a tractive friction wheel, a DC motor, and a reduction drive connecting the motor to the friction wheel;
• (b) a drive unit subframe having the drive unit mounted thereon and mount means for movable mounting of the subframe;
• (c) a drive unit mount having securement structure fixedly fastened to said lift frame, subframe support structure secured to said mount means with said subframe and drive unit being mounted on and being relatively movable with respect to said support structure;
• (d) self-operating biasing means at least partially on said subframe and drive unit for resiliently biasing said friction wheel directly against and in operative frictional engagement with actuator wheel;
• (e) polarized electrical connector means connected to said motor for quick connection and disconnection of said motor to a battery in the boat;
• and
• (f) switch means connected to said motor and said polarized connector for selectively running said motor in either direction to selectively raise or lower the lifting structure and the boat with the motor being powerable by the boat battery.

An electric boat lift drive for a mechanical boat lift having a frame, a lifting structure, a lifting mechanism between the frame and the lifting structure, and a manually operable actuator wheel of at least two feet in diameter, comprising:

• (a) a tractive drive unit having a drive wheel, a DC motor, and a reduction drive connecting the motor to the drive wheel;
• (b) a drive unit subframe having a mount securingly receptive of said drive unit, and means for movable suspension of the subframe and drive unit with respect to the frame and the actuator wheel;
• (c) a drive unit mount having means for being secured to the lift frame, and support means for movably supporting and locating the subframe and drive unit;
• (d) means for movably fastening the movable suspension means of the subframe to the support means;
• (e) adjustment means in said unit mount for adjusting the relative positions of the subframe and the drive unit with respect to the actuator wheel;
• (f) a quick connect polarized electrical connector means for connecting the motor to a battery in a boat;
• and
• (g) a normally off control switch having means connected to said polarized connector and to said motor for selectively running the motor in either direction of rotation under the power of the boat battery.

A method of electrically raising and lowering a boat in a boat lift, comprising the steps of

• (a) floating a boat with a battery therein into a boat lift;
• (b) connecting the boat battery to a DC electric motor mounted on the lift;
• (c) switching the motor on in a first direction of rotation and rotating a traction wheel in a corresponding first direction of rotation with power from the boat battery;
• (d) biasing the traction wheel against an actuator wheel of the boat lift with structure operative between a frame of the lift and the traction wheel;
• (e) frictionally driving the actuator wheel in a corresponding first direction to raise a movable portion of the boat lift and the boat up out of the water to a storage position;
• (f) stopping the motor;
• (g) switching the polarity of the electrical connection of the motor to the boat battery and running the motor in a second direction and similarly frictionally driving the actuator wheel in a corresponding second direction and lowering the movable portion of the lift and lowering the boat back into the water with power from the boat battery;
• (h) disconnecting the motor from the boat battery;
• and
• (i) removing the boat and battery from the lowered lift.

A method of converting any one of a variety of manual boat lifts into a boat battery powered boat lift, wherein the manual lift has a multiple post frame, lifting structure, a lifting drive mechanism, and a manual lifting actuator wheel of at least two feet in diameter and fixed in location with respect to at least one post of the frame, comprising the steps of

• (a) securing a drive unit mount to the frame, said mount having a drive unit support structure;
• (b) adjusting the position of the drive unit mount with respect to the actuator wheel in a first co-ordinance direction by sliding the mount to a desired position on the frame and fixing the mount in this desired position;
• (c) adjusting the position of the drive unit support structure with respect to the actuator wheel in a second co-ordinate direction by extending the support structure in a normal direction to the first co-ordinate direction to a desired position and fixing the support structure in the desired position;
• (d) movably suspending an electric tractive drive unit on said positionally fixed support structure;
• (e) biasing a tractive friction drive wheel of the drive unit resiliently against the actuator wheel with self-operating wheel biasing structure;
• (f) quick connecting the drive unit to the battery in a boat to be lifted and then lowered, and providing DC power from the boat battery for selective operation of the drive unit in either a raising or lowering mode.