Abstract: A joystick comprising a control handle within which is located an inclination sensitive potentiometer. The potentiometer includes an elongate resistance element and an electrically conductive liquid wiper. Movement of the potentiometer causes the wiper to flow along the resistance element and to vary the output resistance of the potentiometer.

Abstract: A device for metering the flow of a fluid, such as a lubricating medium, at a controlled rate. The fluid is stored within a reservoir having a resiliently expandable wall which maintains the fluid under pressure. A transparent cover is provided for visual observation of the wall to indicate the volume of fluid in the reservoir. The pressurized fluid is directed from the reservoir through an elongate flow passage having a cross-sectional area which is sized in relation to the passage length to establish a predetermined rate of fluid flow. In one embodiment the device is automatically energized upon threading engagement with the opening of a structure to be lubricated, and can then be disengaged and stored in a partially full condition. In another embodiment the flow rate can be readily varied by changing the length of a circular flow passage, or the device can be energized or de-energized, by rotating the transparent cover.