较长的轴类零件,淬火后需检测其端部硬度时,由于轴较长,将其一端放在硬度计V型铁上,工件不能自行平衡。若另一端用手或其他支承物支承,则测得的硬度值又不易准确。为此,笔者设计了一种平衡臂,结构如附图,将平衡臂套在被测一端,使其平衡即可检测。若因被测轴过长,装上平衡臂重心仍不在检测位 Long shaft parts, to be tested after quenching the hardness of its end, because the shaft is longer, one end of the V-type iron on the durometer, the workpiece can not be self-balancing. If the other end is supported by hand or other support, the measured hardness value is not accurate. To this end, I designed a balance arm, the structure shown in Figure, the balance arm set at the end of the test, so that it can balance the test. If the measured shaft is too long, the center of gravity balance arm is still not in the test position