【国外标准】 Standard Test Method for Determining the Force-Draw and Let-Down Curves for Archery Bows

3.1 This test method establishes the procedure to be used to measure the force necessary to draw an archery bow from brace height to the full draw position, and the holding force necessary to retain the bow string when the bow is let-down from full draw to brace height. The force values taken at increments of draw length are then plotted versus draw length using rectangular coordinates. The resulting curves are known as the force-draw curve and the let-down curve.3.2 The force-draw curve is used to determine the energy that the limbs of the bow store when it is drawn. The area under the curve between the positions of brace height and full draw can be expressed as stored energy.3.3 The let-down curve is used to determine the energy required to restrain the bowstring as the bow is let-down from full draw to brace height. The energy represented by the area under the curve can be subtracted from the stored energy in order to establish the static hysteresis of the bow system.1.1 This test method covers the procedure to be used to determine the force-draw and let-down curves for archery bows.1.2 The values stated in inch-pound units are to be regarded as the standard. The SI units given in parentheses are for information only.1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.