04819910 is referenced by 34 patents and cites 14 patents.

A two piece ramp for drive on leveling of recreational vehicles and trailers. Two interlocking substantially rectangular blocks stacked in horizontal aligned have matching beveled end. The beveled ends slant inwardly in an upwardly direction. The longer base block contains two transverse grooves on the top surface which correlate and interlock with two transverse ridges located on the bottom surface of the smaller top block. When assembled, the angle of the inclined ramp of the base block is continued up into the inclined ramp of the top block, making one continuous inclined ramp. The width of the ramp is sufficiently sized for accommodating the conventional tires commonly used on trailers and RV's and the length is designed for lateral positioning between tandem wheels. The angle of the inclined ramp is structured for easy loading and helps prevent overshooting the targeted position. The flat top area of each block having a slip resistant textured surface.

Title
Trailer leveler
Application Number
7/227004
Publication Number
4819910
Application Date
August 1, 1988
Publication Date
April 11, 1989
Inventor
Paul F Johnston
1432 Nunneley Rd., Paradise, 95969
CA, US
IPC
E02C 3/00
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