Same pressure of two-point clamping device based on permanent force increasing lever - symmetrical toggle mechanism driven by pneumatic muscle

Abstract

Utilizing pneumatic muscle instead of the traditional rigid pneumatic cylinder, the pneumatic muscle has many outstanding advantages such as small ratio between output force and diameter, small ratio between output force and weight. In this paper, two different diameters pneumatic muscle, combined with the permanent force increasing lever-symmetrical toggle force-amplified mechanism, a new type of clamping device has been innovated. The large-diameter pneumatic muscle will be used for the working stroke of the pressure travel, while the small-diameter pneumatic muscle will be used for the return travel. The tension of the pneumatic muscle will decrease with the increases of the contraction, the force-amplified coefficient of the force lever- toggle mechanism will increase with the decrease of the pressure angle, which is taken full account of this complementary relationship between them. So the output force curve of the press is improved smoothly. The working principle of the system is analyzed and mechanics calculating formulae are given. The clamping device was most used such as: the workpiece size is big, long distance of two pressure head, two pressure head need the same clamping force.