| 摘要 |
<p>A telescopic undercarriage for raising and lowering a frame. The undercarriage includes a base section having a pair of parallel base legs extending from a first end to a second end of the base section, the base section including a first plurality of braces extending between respective upper surfaces of the base legs and a second plurality of braces extending between respective lower surfaces of the base legs, the base legs, first plurality of braces and second plurality of braces collectively providing an elongate central base section passage. The undercarriage also includes an extendable section slidably disposed within the base section passage and having opposed legs, a drive system for extending and retracting the extendable section relative to the base section.</p> |
