摘要 |
The hardness meter is so designed as to render the applied measurement load independent from the force that the operator is capable to exhert and as to provide an instantaneous load permitting a precise measure even if the equipment is shifted during the operation. Such hardness meter includes, between the mobile structure operated by the user's hands and the penetrating pin, a device capable of exherting an instantaneous force on the penetrating pin. This device is formed by a plated spring (49) carried by an inertia mass (45) sliding along the guiding columns (10 and 11) and presenting a convexity which may be released from one side to the other of the median plane; when it is arranged on one side of the plane it is loaded and when it turns to the other side provides the instantaneous force which throws along said columns the inertial mass braked, however by friction means (50, 51 and 52) thus preventing the discharge of the reaction forces against the operator's hands. |