At the present time there is a great variety of various hand trucks, dollies, and wheeled carriers which can be selected for transporting heavy longitudinal objects such as panels, mattresses, doors, etc.
One such device (U.S. Pat. No. 3,090,635 to M. Masterson, 1963) comprises an elongated bed for supporting an object to be transported, and a pair of wheels journalled on a common axis. In other words, the wheels are parallel to each other with the load being located between the wheels. A disadvantage of this device is that it does not have any means for fixing the load during transportation and the operator has to manually support the load while pushing the device in the required direction.
Another hand truck (U.S. Pat. No. 4,695,067 to R. Willey, 1987). for transporting longitudinal objects contains a wheeled axle with parallel wheels installed on the ends of the axle, a load-supporting platform located between the wheels, and a spring-loaded clamping mechanism for clamping the load in the course of transportation. This truck requires a space between the wheels and cannot be made narrow.
Many other conventional wheeled hand trucks for transporting longitudinal objects are known, but they all have at least two parallel wheels installed on a common axis. In other words, such hand trucks always require a space between their wheels and therefore cannot be made very narrow. For this reason, conventional hand trucks cannot be used in very narrow spaces.
In case the hand truck is a two-wheeled device, it has no self-supporting means and therefore requires that the operator support the truck during loading, unloading, and transportation.
In other words, existing hand trucks for loading, unloading and transporting longitudinal objects are inconvenient in use, require extra space in storage, and must be supported by the operator in use.