Mechanically operable suction device for lifting and holding objects

摘要

A mechanically operable suction device for lifting and holding objects includes a housing having therein an intake chamber adapted to be connected to a vacuum source, an intake orifice opening into the intake chamber from the surrounding atmosphere, and a cylinder chamber. A valve member within the intake chamber is movable between a ready position sealing the intake orifice and a suction position spaced from and opening the intake orifice. A plunger is connected to the valve member and extends therefrom through the orifice. Abutting the plunger on an object to be lifted moves the valve member from the ready position to the suction position. A control piston connected to the valve member extends into and seals the cylinder chamber from the intake chamber. The control piston is movable with the valve member between first and second positions when the valve member is in the ready and suction positions thereof, respectively. A first surface area portion of the control piston is exposed to atmospheric pressure when the control piston is in the first position thereof, and a second surface area portion of the control piston is exposed to atmospheric pressure when the control piston is in the second position. The second surface area portion is smaller than the first surface area portion, and the cross-sectional area of the intake orifice is less than that of the first surface area portion and greater than that of the second surface area portion.