Abstract: A cartridge style, pop up, differential pressure indicator includes a threaded body member, a cover structure and a cylindrical indicator button, which carries a magnet at its lower end, and is slidably supported in the cover for movement between a depressed, hidden position and an extended indicating position. The button is engaged at one side by a leaf spring which in the depressed position urges a lip on the button under a ledge in the cover to serve as a detent. A piston slidably supported in the body is subject to differential fluid pressures and carries a magnet at its upper end, poled in a manner to repel the magnet in the indicator button to urge the latter against the bias of the detent spring and upwardly to the extended, indicating position. A semicircular bimetal strip supported in the cover engages the detent spring at lower temperatures to prevent false release of the indicator button due to cold weather, high fluid viscosity situations.

Abstract: The invention is a device which provides for separation of contaminants from a relatively high velocity stream of gas. The invention provides a first stage wherein the gas stream is decelerated and the contaminant particles are caused to separate from the air stream by interacting with a first surface. The interaction results in the particles to acquire a radial velocity vector and by virtue of the momentum of the contaminants particles. The contaminant particles are forced to the outer layer of the gas stream. The second stage of separation provides for further magnification of the radial velocity vector and also induces a slight tangential velocity component to the contaminant particle. By impacting the contaminants against a vane mounted within the gas stream, the contaminant particles, as a result of this impact, acquire a slight swirl or circular motion which causes the contaminant particles to be more localized.