HYDRAULIC JACK Russian patent published in 2014 - IPC B66F1/08 

FIELD: construction.

SUBSTANCE: hydraulic jack comprises a vertical cylinder, a piston, an oil tank with a piston pump, having suction and injection valves, a handle, kinematically connected to the pump piston. Inside the vertical cylinder there are two longitudinal slots arranged opposite to each other on the line of the diameter, having in the upper part holes for connection with atmosphere. An attachment is fixed to the lower part of the piston, and this attachment is made in the form of two discs of such diameter, upper and lower ones, connected by their end surfaces to each other by means of a bolt. Inside the discs there are two cavities that do not communicate to each other, formed by vertical, transverse and inclined surfaces. Both cavities are of identical shape. Opposite transverse and inclined surfaces of the inner cavities are equal in area, and forces acting at them are balanced. Vertical surfaces of one inner cavity are equal in area to vertical surfaces of the other inclined cavity, and forces acting at them are balanced. In the upper part at the side of the piston both inner cavities are closed, and the plane of the bottom of each one is parallel to the lower end surface of the piston. The area of the bottom of each inner cavity is an additional surface, at which liquid applies pressure that is not balanced anyhow and matches in direction with the pressure at the lower surface of the second disc of the attachment. Inlet holes of both inner cavities are connected to the inner longitudinal slots of the body. Ledges on the upper disc that are elements of inlet holes enter these slots on the upper disc. One cavity inside discs is turned by 180° in the horizontal plane relative to the other cavity.

EFFECT: increased force at a piston and higher load-carrying ability.

13 dwg