A self-resetting, automatic hinge, comprising:
- a sleeving compartment complete with a sleeving and a fix plate annexed thereto, the sleeving having a square entry port, a cylinder column, complete with a hollow cylinder and a fix plate annexed thereto and a longitudinal guidance groove on an internal surface thereof, serving to set in transmission elements including:
- a transmission lever, a top of said lever having a substantially square stem, with an annular washer provided underneath the substantially square stem and bearing further down, the bearing being engaged into a concave ring provided in a middle of a screw collar provided on the transmission lever in a manner to project a little over the surface of the screw collar and to adhere tightly to the bottom of the annular washer so as to serve to avoid frictional drag on the transmission lever in rotation, on top of the transmission lever there is furthermore provided a ring groove alongside an outer rim thereof, to be reinforced by facilitating holding thereof by the sleeve of a bumper to be provided otherwise, an underside of an annular ring being formed into a round stem with a two-way helical groove provided over an outer surface above the bottom of said round stem, an extension thereof being executed into a smaller concentric stem, a middle portion of the round stem that is part of the transmission lever being furnished with a small round hole that serves to provide for a passage along the hollow interior of the transmission lever;
- a sliding sleeve, complete with one set of inner and outer pins projecting from an internal surface and outer surface thereof respectively, the bottom of said sliding sleeve is further provided with a round hole and two relatively smaller holes;
- the sliding sleeve being incorporated to the transmission lever complete with inner pins for sliding coupling to a two-way helical groove whereas an outer pin is to be engaged to the guidance groove provided on the inner surface of the cylinder, such that the round hole at the bottom of the sliding sleeve will allow penetration thereinto by a smaller round stem provided on the transmission lever;
- a piston, attached to the bottom of the sliding sleeve and having a round hole and two relatively smaller holes of the same dimension as those provided at the bottom of the sliding sleeve aligned therewith being fastened with screws;
- an oil-proofing ring, made of rubber and bonded with an iron piece underneath, to be secured to the position of the round stem as provided below the substantially square stem provided as a part of the transmission lever to enhance security from displacement;
- a spring, disposed around the transmission lever and lying between the oil-proofing ring and the sliding sleeve;
- and
- a threaded adjusting bolt, a tip of which is conical, serving to adjust and restrict an aperture port provided at the terminal end of the transmission lever.