GB670405A - Means for controlling a member of great length for use with wave guides - Google Patents

Abstract

670,405. Wave-guides. BRITISH THOMSON-HOUSTON CO., Ltd. April 20, 1950 [April 22, 1949], No. 9744/50. Addition to 668,782. Class 40 (viii). [Also in Group XL (c)] In a wave-guide according to the parent Specification in which an adjustable member is movable in a direction so as to alter the width of the guide and vary the phase velocity of waves passing along the guide, the adjustable member is moved uniformly at all points along its length by a plurality of means operable from a mechanism attached to a support for the guide, the mechanism being itself operable by an external source of power. In Fig. 1, the wave-guide comprises the space between a channel member 10 and a member 1 movable vertically between guide supports 4, 5. A source of power (not shown) drives bevel gearing 11, 13 which, through a pin and slot connection 15, 16 imparts an endwise reciprocating motion to a series of rods such as 21, 22 along the length of the guide. At intervals along the guide the rods are coupled to levers 24 pivoted at 28 and having at their free ends pin and slot connections 30, 32 for imparting a vertical reciprocating movement to the adjustable member 1. Endwise movement of the member 1 is prevented by a roller 41 at each end. Alternatively the levers 24 may carry cams at their free ends which engage rollers on the upper edge of the member 1; or wedge-shaped cams carried directly on the rods 21 may engage rollers on the member 1. In a further modification, Fig. 4, the rods 21, 22 are rotatable by a source of power and carry cams 71 which act through a roller 77 and plunger 76 to cause transverse movement of the member 1; or the rotatable rods may be coupled to the member 1 by a crank and eccentric mechanism. In all cases where cams are used, tension springs keep the member 1 in operative connection with the cams.