GB371853A - Improvements in liquid level indicators for reservoirs - Google Patents

Abstract

371,853. Indicating liquid levels. FARFALLINI, I., 28, Via Aquila, Turin, Italy. Jan. 20, 1931, No. 1951. [Class 123 (i).] In a liquid level indicator of the type in which a flexible transmission is actuated by hand at the indicating point to an extent which is determined by the position of a float, the flexible transmission comprises a flexible wire surrounded by a helical coil of relatively large pitch, and then by the usual casing. In Fig. 1, a pointer 1<11> moves over a graduated dial, and its spindle is provided with a pinion 3 gearing with an annular-toothed rack 4 connected to a wire 5 which is attached at its further end to a sliding piston 8. The piston is guided in a tube 9 by a slot moving over a fixed pin 11 and is pressed outward by a spring 10. The wire 5 is tensioned between the springs 10, 12. The other end of the rack is connected to another flexible wire 13, and, in accordance with the invention, a helical coil 14<1> of relatively large pitch is interposed between the wire 13 and the flexible metal casing 14 in order to reduce friction. A similar coil 6<1> is arranged in the casing 6, and is preferably of smaller pitch, while the wire 5 may be of a material such as twisted catgut. The other end of the wire 13 is attached to a rack 15 and the wire is tensioned by a spring 16. The springs 12, 16 are each weaker than the spring 10. The rack 15 engages a pinion on a spindle 19 having a helical groove 19<1>, and passing through a float 22. As the float moves vertically due to variations in liquid level, it is also moved angularly, and thereby determines the amount of rotation which can be given before the stop 22<1> comes into contact with a projecting strip 21. This rotation is effected by pressing the knob 7, and its amount is indicated by the pointer 1<11>. In a modification, hand actuation of the flexible wire is effected bv a knob on the spindle of the indicator pointer, and in another modification, by means of a pawl' device which actuates a rack on an extension of the rack 4.