초록 ▼

A transversely mounted, single pneumatic spring, and dual bell crank and idler link assembly providing a compact counterbalance for hinged closures such as automobile trunk lids. Pneumatic spring enhancements, e.g., a multi-output force feature and a pressure decay compensation feature may be incorp

A transversely mounted, single pneumatic spring, and dual bell crank and idler link assembly providing a compact counterbalance for hinged closures such as automobile trunk lids. Pneumatic spring enhancements, e.g., a multi-output force feature and a pressure decay compensation feature may be incorporated in the spring unit to enhance opening of the lid and to improve life expectancy of the pneumatic spring by minimizing and effectively negating pressure loss due to leakage of gas past the shaft seal. Excess spring cylinder length can provide space or volume zones used for the enhancement features. Structure which provides a multiple output force for the pneumatic spring, utilizes positioning of the spring shaft end bushing and seal to vary the working volume by changing effective cross-section area of the piston shaft near the end of a compression stroke. The extra cylinder length enables a sealed partition wall to separate extra volume and the operative volume part of the cylinder. The extra volume is filled with a supply of gas under higher pressure than that of the spring operative gas pressure and, in conjunction with permeability characteristics of the spring shaft seal and the partition wall seal, enables compensation for leakage from the cylinder. Multiple force output provisions can be used in a substantially vertically disposed spring, filled with a predetermined quantity of oil.

대표청구항 ▼

A pneumatic spring link comprising: a cylinder assembly with a closed end; a piston assembly in said cylinder with a piston shaft extending from the other end of said cylinder, bushing means on said shaft, an annular seal means around said shaft, a piston means fixed on the end of said shaft; the ot

A pneumatic spring link comprising: a cylinder assembly with a closed end; a piston assembly in said cylinder with a piston shaft extending from the other end of said cylinder, bushing means on said shaft, an annular seal means around said shaft, a piston means fixed on the end of said shaft; the other end of said cylinder having means to retain said bushing means within said cylinder; said shaft seal means providing a seal against the cylinder, and a dynamic seal around said shaft; a predetermined small quantity of oil being contained in said cylinder; a predetermined accurate quantity of gas under at least several atmospheres of pressure in said cylinder; and wall means within said cylinder, at a location between the retracted position of said piston means and said closed end, fixed relative to said cylinder wall providing a partition wall dividing said cylinder into plural chambers, the chamber closest to said closed end being a fixed volume chamber; said wall means having a peripheral seal means engaging the inner surface of said cylinder and providing a seal against gas flow at least from said fixed volume chamber past the sealing engagement of said peripheral seal means into the remaining space of said cylinder; said fixed volume chamber containing a predetermined quantity of gas under greater pressure than the gas in the remaining space of said cylinder when the shaft is in a retracted condition; said annular shaft seal means and said peripheral seal means having specific gas permeability characteristics, whereby said wall means and the fixed volume chamber with gas under greater pressure provides a pressure decay compensation means aiding maintenance of desired pressure in the cylinder space occupied by said piston shaft.