| 摘要 |
An apparatus includes a swivel having a first flange with a first pivot on one side of a swivel pivot, and a second flange with a second pivot on an opposite side of the swivel pivot, and first, second, third and fourth rods. The first and second rods are each pivotally attached at a respective first end to the first pivot and extend outwardly therefrom. The third and fourth rods are each pivotally attached at a respective first end to the second pivot and extend outwardly therefrom. The first and third rods are respectively pivotable about the first and second pivots in a first plane, and the second and fourth rods are respectively pivotable about the first and second pivots in a second plane, wherein the first plane is parallel to the second plane. |
