GB1470784A - Hydrostatic nuts - Google Patents

Abstract

1470784 Screw and nut gearing HORSTMANN GEAR CO Ltd 13 March 1975 [18 Dec 1973] 58453/73 Heading F2Q A hydrostatic nut, Fig. 1, is longitudinally divided into two or more elements, 1, 4, &c, each carrying a portion of the internal thread, each element having a plane radial or part chordal face 5 abutting a corresponding plane face of an adjacent element, and one of these abutting faces is provided with recesses 9, Fig. 4, which form fluid flow channels leading from an outer fluid feed passage in the nut to the internal thread. In an alternative embodiment, Fig. 10, the fluid feed passage 40 communicates with short recesses 42 in one plane face, and the fluid flow channels 43 are formed as slots in a sheet metal member 39 which is interposed between the adjacent plane faces, the closed ends of slots 43 overlapping the recesses 42. An external casing member 38 surrounding the feed passage 40 may carry a union fitting 41 for entry of the fluid, which is fed to the flanks of the nut thread and into the clearance space 37 between the nut and a mating screw 34, with the fluid outflow emerging from the ends of the nut thread. In another embodiment, Fig. 11 (not shown), a number of fluid unions are disposed around the nut, and alternate unions serve respectively for the inflow and outflow of fluid. Separate fluid supply lines, severally controlled by flow restrictors, may be fitted. The separate nut elements may be secured together by bolts, clamps or adhesive, or may be secured within an external assembly.