초록 ▼

A straddle crane including four vertical column members, two side beam or torsion members, and at least one header beam member, and having wheel or caster assemblies supporting each vertical column member. The straddle crane is implemented for two-wheel or four-wheel steering and for two-wheel or fo

A straddle crane including four vertical column members, two side beam or torsion members, and at least one header beam member, and having wheel or caster assemblies supporting each vertical column member. The straddle crane is implemented for two-wheel or four-wheel steering and for two-wheel or four-wheel driving with open or closed ends. The structures of the header beam and the side beam members are appropriately selected, and the attachment means therefor to the vertical column members are chosen to accommodate the various forces and stresses occurring on the structure during normal operation over uneven terrain or surfaces. The header beam member is sufficiently flexible to permit movement of the casters over and in contact with uneven terrain without producing unacceptable shear stresses in the header beam member. The torsion beam member defines a closed geometric figure in cross section to provide torsional and bending resistance to the loads applied to the vertical columns.

대표청구항 ▼

In a multi-wheeled straddle vehicle having two pairs of load bearing columns with casters at the lower ends thereof, the improvement comprising: a torsion member having a cross section defining a closed geometric figure connecting each member of one pair of columns with a corresponding member of the

In a multi-wheeled straddle vehicle having two pairs of load bearing columns with casters at the lower ends thereof, the improvement comprising: a torsion member having a cross section defining a closed geometric figure connecting each member of one pair of columns with a corresponding member of the other pair of columns by means of gussets at each end of said torsion member, the structure and size of said torsion member providing sufficient torsional and bending resistance to support downward and inward loads applied to said load bearing columns; and a header beam member having an open cross section and a tubular center, said header beam member being sized and dimensioned to provide sufficient buckling resistance and being sufficiently flexible to provide for movement of the casters over and in contact with uneven terrain without producing unacceptable shear stresses in said header beam member, said header beam member connecting the members of one pair of load bearing columns at an upper portion thereof.