Method of and apparatus for boring holes under streets, highways or the like

Claim 1

Apparatus for boring a hole generally horizontally through the ground underneath an existing structure, operating via a trench dug in the ground extending laterally outward from one side of said structure in the desired vertical plane of the hole, said apparatus comprising a vehicle aDapted to span the trench, said vehicle having axle housings at the front and rear thereof, each axle housing having a central differential housing section with a differential therein and axle shafts extending from the differential to the outer ends of the housing, wheels on the ends of the axle shafts, a vehicle drive shaft extending between the two housings having pinions at its ends for driving the axle shafts of each housing, an engine on the vehicle, first transmission means on the vehicle driven by the engine, a boring drive shaft extending forward from the vehicle at the level of and in front of the central differential housing section of the front axle housing, means journalling said shaft for both rearward and forward thrust thereon, means for driving said shaft from the output of said first transmission means, a boring rod coupling means connected to the forward end of said shaft by a universal joint, said coupling means being adapted for connection thereto of a string of boring rod for rotation of the string by said shaft and lengthwise movement of the string by the vehicle, said universal joint permitting angling of the rearward end portion of the string relative to said shaft, a power take-off from said first transmission means, and second transmission means driven via said power take-off and connected to drive said vehicle drive shaft.