A screen plate with grooves is described. The grooves are provided at the bottom with perforations. The direction of the grooves substantially deviates from the flow direction of the pulp to be screened. By different inclination of the side planes of the grooves the turbulance force on the pulp can be varied to meet the different needs of various screening applications.

A pin screen includes a plate having a plurality of closely spaced small apertures. The plate is supported in a substantially horizontally fixed position, and each of the apertures defined therein are adapted to receive a pin in a substantially vertical orientation. The heads of the pins are larger than the diameters of the apertures to assure that the pins do not fall through the apertures. The pins are vertically movable relative to the horizontal plate between a lower position in which the bo...

A focusing screen includes a plurality of light deflecting portions, each of which includes a prism component having a light deflecting function for providing part of an out-of-focus image with displacement in one direction, and a diffraction grating component formed on the prism component and having a plurality of unit structures. At least a portion of each of the unit structures is formed by a curved surface.

A well screen is provided with a coating of a fusible material for corrosion protection and to prevent screen plugging during storage, handling and placement. The fusible material, preferably wax, is selected for its ability to melt at the normal subsurface temperature of the well. This opens the screen to production, permitting the passage of fluids therethrough.

An industrial screen such as used to process coal, ore and the like comprises elongate plastic profile bars having depending flanges clad by metal sheaths which reinforce the profile bars. The clad profile bars are pressed into notches located in metal support members which support the bars in spaced apart parallel relationship. Metal rods which pass under the support members and transversely through the flanges as well as their reinforcing sheaths secure the profile bars to the support members....

A luminescent screen consists of a carrier and a luminescent layer carried by the carrier. The carrier consists of a substance which is the basic substance of the luminescence.

An electrophotographic printing machine in which an arcuate screen member has a curvature substantially equal to the curvature of an arcuate photoconductive member employed therein. The centers of curvature of the screen member and photoconductive member are located in substantial coincidence with one another.

A plastic funnel having a truncated cone-shaped filtering element which snaps into the neck thereof so as to provide a removable, replaceable, and easily cleaned filtering medium having a smooth flow path and a large filtering area relative to the exit area of the funnel.

Folding glass doors have a novel pivotal mounting for easy removal for cleaning. An optional wire mesh curtain may be mounted behind the doors. A draft control at the bottom of the frame is adjustable by a foot or hand operated lever. Installation of the frame is facilitated by an improved lintel bracket.

A screen ceiling is disclosed comprising a plurality of elongated panels arranged generally in vertical planes with adjacent ends of panels secured to supporting gusset joints in turn suspended from an overhead fixed support structure. Each gusset joint has an outwardly extending support for each panel connected thereto. The outwardly projecting supports in turn have projections extending through one or more openings in the panels which openings are adjacent the ends thereof. Joining and locking...