12,103. Thompson, W. H., and Thompson, R. June 3. [Cognate Application No. 24,607, A.D. 1908, dated Nov. 16.] Lift valves; seats.-The hand-wheel of a screwoperated lift valve is arranged so as to operate between the usual gland on the bonnet and the valve body. In one form, shown in Fig. 1, the valve seat c2 is formed on the underside of a perforated cup c held in position by a nut D engaging a screwed shank c4. The valve stem B passes through a stuffing-box E formed in the shank, and is connected by a washer f4 and nut f3 to the handwheel f which has a screwed boss F engaging the screwed shank. A spring f2 is inserted between the nut and the hand-wheel to allow for expansion of the spindle. In a modification, a removable seat is secured to the cup and a separate sleeve is screwed on to the shank to receive the hand-wheel. In a further modification, the sleeve passes into the valve body, where it is secured by a flange and nut. In another modification, the hand-wheel has a second screw-thread, of different pitch, to engage with a screw-thread on the end of the valve spindle, which is provided with a square part to prevent it from rotating. In the form shown in Fig. 5, the hand-wheel engages a screw-thread on the end of the valve spindle and is rotatably mounted on the coupling-nut D, where it is retained by a flanged ring d' which also carries the bolts d2 of the gland.
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