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US 6,290,248 B1Granted
Universal dolly attachment device
OwnerJoe Yrigoyeninventor
Life of this patent
Estimating the term…
Abstract
An improved trailer dolly having a fifth wheel and also carrying a ball-type trailer hitch to give the driver the option of towing either type of trailer and having steering means built into the dolly to provide sure and positive steering and control of the towed trailer.
Claims30
A trailer dolly comprising:
- a frame,
- an axle supporting said frame,
- steerable wheels mounted on each end of said axle,
- a fifth wheel mounted on said frame,
- a ball mount coupling mounted on said frame,
- means for steering said wheels from a towing vehicle,
- means for releasably connecting said dolly to be towed by said towing vehicle,
- a hydraulic reservoir mounted on said frame,
- a double acting cylinder mounted on said axle,
- means connecting said cylinder to steer said wheels, and
- means connecting said reservoir to supply hydraulic fluid to said cylinder to steer said wheels.
8 more elements
A trailer dolly comprising:
- a frame,
- a tongue projecting forwardly from said frame,
- coupling means carried by said tongue for releasably connecting said tongue to a towing vehicle,
- an axle supporting said frame,
- steerable wheels mounted on each end of said axle,
- a fifth wheel mounted on said frame,
- a ball mount coupling mounted on said frame,
- means for steering said wheels from a towing vehicle,
- at least one friction bar carried by said tongue and projecting forward of said coupling means,
- a friction plate formed of high friction material engageable with said friction bar,
- a squeeze plate,
- means for adjustably squeezing said squeeze plate and said friction plate against said friction bar to restrict pitching movement of said tongue, and
- means connecting the forward end of said friction bar to said towing vehicle.
10 more elements
A trailer dolly comprising:
- a frame,
- an axle supporting said frame,
- steerable wheels mounted on each end of said axle,
- a fifth wheel mounted on said frame,
- a ball mount coupling mounted on said frame,
- means for steering said wheels from a towing vehicle,
- a tongue projecting forward from said frame,
- coupling means carried by said tongue for releasably connecting said tongue to a towing vehicle,
- at least one friction bar carried by said tongue and projecting forward of said coupling means,
- a friction plate formed of high friction material engageable with said friction bar,
- a squeeze plate,
- means for adjustably squeezing said squeeze plate and said friction plate against said friction bar to restrict vertical movement of said tongue, and
- stabilizer bars located on each side of said tongue and connectable to said towing vehicle.
10 more elements
A trailer dolly comprising:
- a frame,
- an axle supporting said frame,
- steerable wheels mounted on each end of said axle,
- a fifth wheel mounted on said frame,
- a ball mount coupling mounted on said frame,
- means for steering said wheels from a towing vehicle,
- a first double-acting hydraulic cylinder mounted on said towing vehicle,
- a first piston slideable within said first cylinder and having one end coupled for movement by a steering box of said towing vehicle,
- a second double-acting hydraulic cylinder mounted on said dolly,
- a second piston slideable within said second cylinder,
- means hydraulically coupling said first cylinder with said second cylinder such that movement of said first piston within said first cylinder will cause similar movement of said second piston within said second cylinder, and
- means rigidly yet adjustably connecting said second piston to control movement of said wheels.
9 more elements
A trailer dolly comprising:
- a frame,
- an axle supporting said frame,
- steerable wheels mounted on each end of said axle,
- a fifth wheel mounted on said frame,
- a ball mount coupling mounted on said frame,
- a tongue projecting forward from said frame,
- stabilizer bars located on each side of said tongue and connectable to said towing vehicle,
- means for steering said wheels from a towing vehicle,
- a first double-acting hydraulic cylinder mounted on said towing vehicle,
- a first piston slideable within said first cylinder and having one end coupled for movement by a steering box of said towing vehicle,
- a second double-acting hydraulic cylinder mounted on said dolly,
- a second piston slideable within said second cylinder,
- means hydraulically coupling said first cylinder with said second cylinder such that movement of said first piston within said first cylinder will cause similar movement of said second piston within said second cylinder, and
- means rigidly yet adjustably connecting said second piston to control movement of said wheels.
11 more elements
A trailer dolly comprising:
- a frame,
- an axle supporting said frame,
- steerable wheels mounted on each end of said axle,
- a fifth wheel mounted on said frame,
- a ball mount coupling mounted on said frame,
- means for steering said wheels from a towing vehicle,
- a tongue projecting forwardly from said frame to connect said dolly to a towing vehicle,
- stabilizer bars located on each side of said tongue and connectable to said towing vehicle,
- said stabilizer bars being rigid members extending farther forward than said tongue and extending parallel to said tongue on opposite sides thereof and serving to connect said dolly with said towing vehicle to permit limited rolling motion of said dolly with respect to said towing vehicle, while preventing yawing and also serving to restrict pitching movement of said dolly with respect to said towing vehicle.
6 more elements
Dependencies are inferred from the claim text.