Patent ID: 9677347
Date: 2017-06-13
CPC Classifications: E21B,F16F,G01V

Claim:
1. A downhole logging tool, comprising: a shock absorber disposed for downhole use on the downhole logging tool, the shock absorber comprising an elongate hollow member defined by a series of mutually aligned, plastically deformable annuli, each of the annuli being of similar dimensions to one another and having aligned perforations defining the hollowness of the elongate hollow member, whereby the elongate hollow member defines a hollow cylindrical shape, the annuli being spaced from one another in a direction of elongation by respective rigid spacer members secured to the annuli, wherein the annuli of the series are so spaced from one another by one or more of the spacer members such that, on compression of the shock absorber, the annuli deform plastically to a lesser extent in regions at which the spacer members are secured than at other regions, arrangement of the annuli and the spacer members causing compression to occur substantially parallel to a length of the shock absorber, and wherein at least two of the annuli adjacent one another in the series are spaced from one another by three or more of the spacer members that are disposed at equally spaced intervals about a circumference defined by the annuli.