The present invention relates to wheelbarrows, and in particular, to readily maneuverable wheelbarrows with ergonomic handle designs and requiring small leverage to lift a load.
Wheelbarrows are well known as a tool for moving heavy loads for a short distance. Typically, a wheelbarrow has a container made from sheet metal supported by a forward wheel and two rear legs. The handles are typically formed as a pair of parallel pipes extending to the rear of the container.
The conventional wheelbarrow handle design suffers from a number of disadvantages. Although the conventional handle design is relatively comfortable to lift, the forward directed force required to move the wheelbarrow must be directed along the length of the handles. This applies transverse stress on the wrists of the user, rapidly leading to tiredness and aching joints. The conventional wheelbarrow handle design is also inconvenient for tipping-up the wheelbarrow, typically requiring at least one change of hand position during the lifting action.
Various other features of the conventional wheelbarrow design also have drawbacks. The single, forwardly-placed wheel makes the wheelbarrow unstable when the rear legs are raised. This instability is further aggravated by the positioning of the center of gravity of the container well above the wheel. Finally, the forward positioning of the wheel relative to the center of gravity leaves a large proportion of the loaded weight to be supported at the handles by the user.
Some of the aforementioned shortcomings have been addressed by a number of two-wheel wheelbarrows designs, typically made form molded plastic. An example of such a wheelbarrow is described in U.S. Pat. No. 5,615,903. Clearly, such a design is considerably more stable than a single-wheeled design. However, the high center of gravity, forwardly placed wheels, and poor handle design still present considerable disadvantages. Linkage between the two wheels may also make it difficult to steer the wheelbarrow in tight turns.
There is therefore a need for a wheelbarrow which has ergonomic handle design, and which is stable and easy to lift and maneuver.