IMPROVEMENTS IN OR RELATING TO ADJUSTMENT DEVICES FOR ADJ USTMENT TO BE EFFECTED BY A PRESSURE REGULATOR

摘要

1445110 Screw and nut gearing; valves SPIRAX SARCO Ltd 3 Dec 1974 [6 Dec 1973] 56725/73 Headings F2Q and F2V In a screw and nut gear which provides a lockable means of adjustment for an air line pressure regulating valve, Fig. 1, an adjuster member 13 in screw threaded engagement with a housing 11 is rotatable by an adjustment knob 12, through a hexagonal spigot 14 slidingly engaged in a corresponding aperture in the adjuster 13, whilst the knob 12 is slidably mounted on the housing 11, in such a manner that the knob 12 may be drawn outwards and lodged in a first axial position in which rotation is freely permitted, and it may be slid home to a second axial position in which it becomes locked against rotation. The knob 12 comprises two synthetic plastics members resiliently snapped together, including a cup-shaped member 12A incorporating the integral spigot 14, and a collar member 12B, Fig. 8, and Fig. 6. In the first axial position, inwardly directed tips 16A of resilient lugs, Fig. 8, of collar 12B enter an annular groove 18 in housing 11. In the second axial position, external splines 17 on two regions of housing 11, Fig. 3, engage internal splines 15, Fig. 6, in collar 12B, thereby locking the knob against rotation, and the knob may optionally there be retained by entry of the lug tips 16A into a further groove (not shown). The air flow regulating valve has a body 1 with an air way 2, a diaphragm 3, and a valve member 4, sliding on a spigot 6 with an 0-ring seal interposed, and supported by a valve spring 5. The adjuster member 13, by means of the knob adjustment movements described above, may be used to govern the compression in a diaphragm spring 10, thereby adjusting the setting of the air flow valve. The adjustment means may be coupled to control devices other than air valves.