Patent ID: 7980030

Claim:
A C-type underbracing ( 10 ) for installing on bottom of a utility pole ( 21 ), comprising: a body portion ( 12 ) forming a half-annular shaped cylinder with a rectangular cross section, wherein an outer radius (Rb) of the body portion ( 12 ) is enlarged when compared to an inner radius (Rp) of the body portion ( 12 ), and the inner radius of the body portion ( 12 ) is slightly larger than the outer radius of the utility pole ( 21 ), a pair of enlarged end portions ( 11 , 11 ′) forming rectangular-shaped blocks with rectangular cross sectional areas, which are larger than that of the body portion ( 12 ), a pair of conjunction portions ( 17 , 17 ′) having top surfaces being inclined from the body portion ( 12 ) to the enlarged end portions ( 11 , 11 ′), base surfaces being flat and lying on a bottom plane to align bottom surfaces of the body portion and the enlarged end portions, inner lateral surfaces being contacted to the circumference of the utility pole ( 21 ), outer lateral surfaces forming slightly convex contours from the body portion ( 12 ) to the enlarged end portions ( 11 , 11 ′), so that the cross sections of the conjunction portions are varied from the cross section of the body portion ( 12 ) in the width and the height portion to the cross sections of the enlarged end portions ( 11 , 11 ′), a hook receiving hole ( 13 ), which is horizontally through a center of the body portion ( 12 ), a hook mounting seat ( 15 ) forming a circular-shaped flat area, which is sunk down around the hook receiving hole ( 13 ) for increasing frictional forces, a pair of nut mounting portions ( 16 , 16 ′) forming flat surfaces for seating nuts and a pair of slit-shaped holes ( 14 , 14 ′) for horizontally inserting U-bolts ( 20 ) through the body portion ( 12 ), wherein said nut mounting portions ( 16 , 16 ′) and slit-shaped holes ( 14 , 14 ′) are disposed proximate both sides of said hook receiving hole ( 13 ), and a pair of seating surfaces ( 18 ) of the nut mounting portions ( 16 , 16 ′) being inclined 5°˜10° outward for easily tightening the nuts, so that the U bolts ( 20 ) and nuts gradually move outward of the slit-shaped holes ( 14 , 14 ′) to be prevented the nuts and U bolts ( 20 ) adhering to the mounting portions ( 16 , 16 ′) during the installation of underbracing ( 10 ).