A method and means for indicating the level of electrolyte in a vehicle battery

摘要

837,816. Batteries. DECOURT, R. R. Nov. 15, 1956 [Nov. 29, 1955; Dec. 14, 1955; July 9, 1956], No. 34943/56. Class 53. [Also in Group XVIII] The necessity of topping-up the electrolyte in an accumulator A is indicated by, for example, a lamp 15 when the electrolyte drops below the level of any of the outlets a, b, c of a tube 1 leading into a closed, slightly pressurized, chamber 2 the liquid space of which is connected to the liquid space of a chamber 12 which is at atmospheric pressure. The resultant reduction of pressure in the chamber 2 allows the level of the liquid, preferably oil, therein to rise with consequential drop in the liquid level of the chamber 12, causing a float 13 to complete the electrical circuit, supplying the lamp 15, by connecting across terminals 11, 14. The lamp 15 may be tested by closing a switch 16 shortcircuiting the terminal 11, 14. The chamber 2 is supplied with air from a chamber 4 through a tube 3 the end of which dips into the liquid in the chamber 2, and the chamber 4 contains a resistor 6 for heating, and thus pressurizing, the air in the chamber 4 and consequently, if the accumulator has been topped up, the air in the chamber 2, the resistor circuit being under the control of a car tail lamp switch 8 which is closed when a brake pedal is actuated. The resistor circuit is also under the control of the float 13 which breaks the contact between terminals 10, 11 when the pressure in the chamber 2 is high enough. On the resistor circuit being opened the chamber 4 cools down causing air to be drawn into it through a tube 5 one end of which is open to the atmosphere and the other end of which dips into the liquid in the chamber 4. Fig. 2 shows an alternative form of the apparatus, the chamber 12 being contained in the chamber 2 and both of these chambers being contained in the chamber 4 while the terminal 14 is placed at the centre of the chamber 2 to reduce the effects of car movement on the liquid level. There are two resistors 61 and 611 for use alternatively with a 12-volt or a 6-volt accumulator, the resistor circuit including a bimetallic strip 17 to break the circuit on a high temperature being reached consequent on prolonged braking with low electrolyte level. Fig. 5 (not shown) shows a manifold connected to the end of the tube 1 for fitting to the battery A. Various alternative means for supplying the chamber 2 with gas under pressure are suggested; for example an injector may be operated by heat from a car engine, or a hand- or pedal-operated plunger, or by the pressure of the air due to the motion of the car, or by using the pressure of gas formed within the accumulator itself. Variations of the last-mentioned method are described with reference to Figs. 6, 7 and 8 (not shown).