An improved apparatus for selectively controlling the passage of livestock from fields

摘要

987,173. Cattle guards. W. J. AMOS. Jan. 31, 1963 [Feb. 5, 1962], No. 4276/62. Heading E1G. Apparatus for controlling the passage of live-stock from fields comprises a pair of frames 10, 11 forming a passageway across which extend a series of chains 18, preferably spaced nine inches apart and detachably secured to rails 17 mounted between the frames 10, 11 and posts 16 secured to them. The chains may be replaced by rods or cables (not shown). Each rail 17 is supported by cables 19, 20 associated with a spring controlled lever 22 tending to raise the rails. Adjustable stops 27 are mounted on the posts 16. This spring mounting allows the chains to yield when at a height of nine inches for a vehicle to pass. At this height it is stated that both sheep and cattle will be prevented from passing. If chains are removed to make the spacing twenty-seven inches and the remaining chains are raised slightly sheep will still be deterred but cattle will step over the chains. To restrain cows while allowing calves to pass the rails are raised only sufficiently to allow the calves to pass below the chains.