GB1483474A - Fluid resistors - Google Patents

Abstract

1483474 Fluid regulation SYBRON CORP 27 Nov 1974 [3 Dec 1973] 51408/74 Heading G3H [Also in Division B3] A fluid resistor comprises a laminated member 36, Figs. 3 and 4, having a rigid substrate provided with a flat surface and a metallic layer, e.g. copper, of substantially constant thickness deposited on the surface. The member 36 has a groove 35 formed through the metallic layer by photoetching. A rigid plate 42 co-operates with the grooved surface of the member 36 to close the groove and thereby define a capilliary passageway extending between inlet and outlet passage means. In the embodiment shown the plate 42 is formed with an inlet passage (60) therethrough, Fig. 2 (not shown),and is angularly adjustable to vary the effective length of the capilliary passageway between the inlet passage and an outlet passage 40 in the member 36. Alternatively the member and plate may be relatively adjustable along a linear path. In another embodiment, Figs. 9 to 14 (not shown), the laminated member (140) and plate (134) are relatively fixed. However, the member (140) has a pair of grooves (160, 162) formed therein and the plate (134) has two pairs of inlet and outlet apertures, whereby two different resistance paths are available. Alternatively, the apertures may be so arranged in the plate (134) that by its assembly in one of two alternative orientations only one of the grooves is effective. The substrate of the laminated member may be of aluminium in which case it is initially coated with a layer of material resistant to photoetching, e.g. polyethylene, epoxy or polyester adhesive, before receiving the copper layer. The etched copper layer may be coated with a layer of nickel. The substrate may instead be formed of a substance resistant to photoetching, e.g. fibreglass, in which case the initial coating is not necessary. The plate may be of carbon-filled p.t.f.e.