Abstract: A display sign includes a translucent, planar back panel attached to a front, open portion of a generally rectangular housing which contains a light source. Disposed on a front surface of the back panel in a vertically spaced manner are a first plurality of parallel, linear, horizontally aligned tracks, or rails. The display sign further includes a plurality of front panels each having a respective second plurality of horizontally aligned, vertically spaced, linear tracks on an aft surface thereon. Each of the second tracks is adapted to engage a respective one of the first tracks on the front of the sign's back panel for securely and removably attaching the front panels to the back panel. The depth of each of the second tracks, or the extent each of the second tracks extends outwardly from the aft surface of a front panel, is the same for all tracks on a given front panel, with the depth of the tracks on adjacent panels being different.

Abstract: A display letter mounting arrangement for use in an open face sign having a flat forward, or display, surface is disclosed. Each letter, or alphanumeric character, is provided on an individual flat panel which is inserted between generally horizontally oriented, parallel, upper and lower tracks. A high contrast, or illuminated, background screen is provided aft of the planar arrangement of letter panels which are positioned immediately adjacent one another. Each panel includes an opaque partition secured to a lateral edge of the panel along the length thereof so as to be positioned between immediately adjacent panels on the sign in an overlapping manner. Each partition, or inter-panel strip, has a cross section in the form of an "h", with the recessed portion thereof securely attached to the lateral edge of a panel permitting the extended portion of the partition to engage and overlap the proximal edge portion of an immediately adjacent panel.

Abstract: Method and means for separating emulsified and entrained oils from water, machine coolants, and substantially any other liquid comprising initially directing a flow stream into an inlet trap for removing relatively large particles from the flow stream, passing the flow stream through a centrifuge for removing substantially all of the entrained solids in the flow stream, moving the flow stream through a de-emulsifier for coalescing of the emulsified oil into droplets sufficiently large for processing in a separator and for filtering any remaining solids from the flow stream, providing a backwash action from the de-emulsifier for recycling of said finally removed solids through the centrifuge, passing the flow stream through a separator for separation of the oil from the other liquid components of the flow stream whereby the separated oil and clean effluent may be removed from the system.