Patent ID: 8561239

Claim:
An apparatus configured to raise and lower an articulating cage with respect to a fixed structure, the apparatus comprising: a pair of support structures configured to be affixed to the fixed structure, wherein at least one of the pair of support structures comprises a spring; first and second lifting arm arrangements, each of said lifting arm arrangements comprising upper and lower lifting arms having: a first end pivotally connected to a respective one of the pair of support structures such that said upper and lower lifting arms of said first lifting arm arrangement are pivotally connected to a first support structure of said pair of support structures and said upper and lower lifting arms of said second lifting arm arrangement are pivotally connected to a second support structure of said pair of support structures; and a second end pivotally connected to the articulating cage so as to allow the second end of the upper and lower lifting arms to pivot relative to a floor of the articulating cage; a load device connected to the spring at one end and proximate to the second end of the first lifting arm arrangement at the other end; and a hoist operatively connected to the load device to cause movement of the load device in order to raise and lower said articulating cage.