Patent GB-656849-A (GB)
Title: Improvements in or relating to fluid flow meters or logs
IPC: G01P5/07
Filed: 1947-12-23
Abstract: 656,849. Logs. ATELIERS NEYRETBEYLIER & PICCARD-PICTET. Dec. 23, 1947, No. 33944. Convention date, Dec. 28, 1946. [Class 97 (ii)] A log or fluid flow meter comprises a helical screw 22, Fig. 1, operating through reduction gearing at least one impulse-generating electrical contact, and a cylindrical body 7 in which is mounted a removable assembly comprising one chamber 34 for the reduction gearing and another chamber 35 for the electrical contact, the chambers being separated by a fluid-tight partition 38, and a conical member 8 coaxial with the body 7 and forming an extension thereof wherein an alignment tube 6 is fitted in which the bearings 2, 3 of the screw shaft 1 are set, the shaft being provided with retaining means for the screw 22. The cylindrical body 7 and the' conical member 8 are assembled together by interengagement of lug extensions 13, Fig. 2, on the member 8 which pass through apertures in, and, on rotation, lock behind a suitably slotted undercut flange 12 on the end of the body 7. These members may be secured together in their interengaging positions by means of an annular spring 10 housed in a recess 8b in the member 8 and having a lateral extension which, in its locking position, lies partly within a recess 12a of the lugs 13 and partly within the slot 12b in the flange 12, and which may be released therefrom by depression of a knob 11. As shown, the shaft 1 drives a worm 36 and worm-wheel 37, the latter being provided with two inclined cam surfaces 42a which engage fingers 41a mounted on a fork 40, thereby causing, in response to the rotation of the screw 22, oscillations of a shaft 39 which passes through the fluidtight partition 38 into the contact chamber 35. Thes oscillations are transmitted to a fork 45, Fig. 4, fitted with fingers which engage alternately pins 44a, 44b which are connected electrically to spring- pins 45a, 45b traversing the contact chamber and through the insulating cover 46 into contact with the enlarged face of a stud 47 to which the external lead is connected. The enlarged face of the stud 47 is provided with a small circle of insulating material and by relative rotation of the parts concerned either pin 45a or 45b may be brought into contact with this insulated spot in order to halve the number of impulses per revolution of the screw 22. The contact chamber 35 may be rotated to affect this adjustment by rotation of the conical member 8 through the intermediary of the alignment tube 6 and the pin connections 9, 55. The bearing assemblies 2, 3 are carried in a housing 5 which at its forward end carries a cap 15 having an annular portion 15b surrounding the shaft 1 with a slight clearance. A cone-shaped sleeve 16, pressed into an annular flange 15a in the cap 15, surrounds the shaft I and together with the cap 15 forms a decantation chamber preventing solid particles from entering the apparatus. A member 18, splined to the shaft 1, extends rearwardly over the sleeve 16 towards the body member 8 but with sufficient clearance to permit its free rotation. The screw 22 is provided with a seating 21 which fits over the member 18 and is held fast to the end of the shaft by a spring-urged bayonet fitting comprising a cylindrical holder 24 provided with spurs 28 fitting in notches in an abutment-ring 30.