摘要 |
<p>The present invention provides an adjustable prop/extensor, which comprises a telescopic member having two or more telescoping sections (3, 4), the prop/extensor further comprising a piston (5) and cylinder means, the cylinder means (3) containing a first pressure fluid, the piston means (5) being associated with one of the telescopic sections (4) and the cylinder means being associated with the other (3) whereby the first pressure fluid acts as a spring between the telescopic sections, the cylinder means being selectively in fluid communication with a reservoir means (14) for storing a second pressure fluid that is less compressible than said first pressure fluid.</p> |