Patent GB-314038-A (GB)
Title: Improvements in or relating to automatic control apparatus
IPC: C10J3/24
Filed: 1928-09-27
Abstract: 314,038. Humphreys & Glasgow, Ltd., (Assignees of Soc. de Construction d'Appareils pour Gaz Ó l'Eau et Gaz Industriels). June 23, 1928, [Convention date]. Water-gas plant. - Apparatus for controlling automatically a cyclic series of operations in gas manufacture, more particularly for carburetted water gas, comprises a fluid pressure distributing device consisting of a piston working in a cylinder having ports disposed according to the cyclic sequence. A main distributing cylinder is used for controlling the movement of those members, the time of operation of which can be symmetrically related to one of the ends of the piston stroke of that distributor, for example the blast valve, steam valve, and reversal valve, and secondary cylinders are employed for the other controls. The main distributor comprises a cylinder 1 with a double piston 2, 3, the rod 4a of which is reciprocated by a cross-head 5. The two secondary distributors have pistons worked from the rod 4a by crosspins 6 moving in adjustable cages 7 on rods 4. The fluid pressure inlets 8 are always situated between two piston heads 2, 3 and the outlets to the hydraulic cylinders for working the blast and steam valves are placed on the main distributor at 11 and 12 at an interval equal to the distance be. tween the outer faces of the double piston. The ends of the cylinders are connected together and communicate with outlets 9, 10. In that part of the piston stroke corresponding to the gas making period is a series of openings 13, one of which is connected to the hydraulic cylinder for reversal, the remainder, provided with plugs, serve for the regulation of the duration of the period of reversed gas making. The outlet openings of the cylinders controlling the stack valve and secondary air valve are placed at points 52 and 53. The cross-head 5 is adjustable on the rod 4<a>. A motor 16 drives a low speed shaft 18 which makes one revolution per cycle and causes, by a crank and connecting rod, the cross-head 5 to reciprocate. The shaft 18 carries a wheel 19 with arms for hand operation and a clutch 24. Indexes on the rods 4a and 4 move over scales on the guides which show the positions of the controlling devices. Each member has a tappet 26 on its associated piston rod which coacts with return bars 27, 28 actuated by levers 29, 30 from the member operated, so that when the member responds to control, a free passage is left for the tappet, but if the member does not respond, a bar 27 is rocked and causes levers 34 and link 35 to withdraw a slide 36 which allows a weighted lever 37 to fall and close valve 41, cutting off the pressure fluid, and to open valve 42, putting the central part of the distributor into communication with the exhaust, and the controls in the stand-by position. A switch 39 is also broken and a reading of the index on the guides shows the defective valve. A hand lever 43 is used to restore the apparatus to its operative position. In the case of failure of current an electromagnet 45 is de-energized and a spring 49 causes a lever 47 to press against a stop 48 on slide 36 and release weight 37.