GB697194A - Improvements in hydrostatic levels - Google Patents

Abstract

697,194. Leads. SCHMIDT, C. E. April 27, 1951, No. 9904/51. Class 97 (ii). A hydrostatic level comprises a base 49, Fig. 1, a reservoir 12 in communication with the atmosphere and rotatably carried by the base, and a hydrostatic communicating member 23, between the reservoir and a level sight 31. The reservoir 12 which together with heads 10, 11 forms a reel for receiving the flexible tube 23 when not in use, is rotatably mounted by plug 46, Fig. 4, and bearings 48 on the base 49, a spring-urged snubber 57 preventing free-wheeling of the reservoir during unreeling. A cranked hollow handle 16 has one end above the level of the liquid 13 which more than half fills the reservoir, the other end being provided with a knob 18 and screwed valve 19 which is opened when the level is in use. One end of tube 23 is attached to an L-shaped connector 20 which terminates at the centre of the reservoir and the other end is fastened by nut 27 to the lower part of a valve body 25. On depressing button 43 against the action of a coiled spring housed in the upper portion of body 25, the valve stem 41 opens a valve and allows the liquid to flow up an L-shaped fitting 28, integral with body 25, into a tubular transparent level sight 31. When the liquid is at an index mark 34, a line is made by scoring blade 36, which is fastened to fitting 28 by an interengaging boss and recess and a securing screw. The base 49 may be secured to a support 63 by co-operating jaws 61, 62, the movable jaw 61 forming the solid end of a housing 60 slidable in apertures in a base flange 54 and tightened by wing nut 69. A closure cap 68 gives access to the hollow interior of housing 60 in which the sight 31 is stored when not in use. A cylindrical cover is provided having a plate and a notched lug to be engaged by jaws 61, 62 and housing 60 and wing-nut 69 respectively.