A FIRE PUMP FOR SMALL BRIGADES.
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A Fire-fighting Equipment for Villages or Small Townships. When Mounted on Six Wheels it is Suitable for Soft Ground.
AFIRE-FICETING unit for the smaller tire-brigades has been prepared by Morris Motors, Ltd. in conjunction with the Gwynne Engineering Co., Ltd., the Gwytme two-stage turbine pump being combined with a Morris 15.9 h.p. chassis, an extremely interesting development of the product being its equipment, when so required, as a siX-wheeler for use in farming districts and in other places where soft ground has to be traversed in order to reach water, so that the Morris-Gwynne fire pump will be obtainable either as a four-wheeler or a six-wheeler, because, of course, in towns and other places where a hard road stir= face can always be guaranteed the employment of six wheels would not be necessary.
The whole idea underlying the design of this unit is cheapness in production in order that it may be brought within the limits of expenditure possible in a small township, or in a combination of villages, whilst, of course, there is the second application of the machine as an auxiliary to fleets of larger engines: Briefly to describe the machine, an exceptionally strong frame with deep channel-section pressed-steel side members, braced with deep Cross-members, has been adopted, an ample margin of strength being obtained without excessive weight. The four-cylindered engine of 80 mm, bore by 125 mm. stroke develops up to 35 h.p. and is the well-known Morris 15.9 h.p. unit with detaohable cylinder head, side-by-side valves, forced-feed lubrication to the three main bearings and trough-feed to the big-ends, the engine being combined unit-wise with the gearbox, and the whole being carried on a three-point suspension system.
The drive is taken from the engine through a single-plate dry clutch, the gearbox gives four forward speeds and reverse, the gear ratios being 1 to 1, 1.7 to 1, 2.3 to 1, 3.45 to 1 and the reverse 4.45 to 1, the final drive to a threequarter floating type rear axle being by an overhead worm. The fire pump is driven by a separate shaft direct from the engine by means of an auxiliary gearbox interposed between the uniVersal couplings on the main cardan shaft, and the pump drive is brought into operation by means of a separate gear lever situated close to the driver's seat. It is quite impossible to engage both pump and the main driving shaft at the same time, and there is also a neutral position which renders both shafts entirely free from the engine.
The pump, as we have said, is of the two-stage turbine type with impellers set back to back in order to minimize end thrust. The central suction is 4 ins, in diameter, and there are two 2-in, discharge branches situated on the pump cover facing towards the rear of the machine and easily accessible for hose coupling. The pump will deliver 250 gallons of water per minute, against a total gauge head of 100 lb. per sq. in. at 2,250 r.p.m., a pumping range being obtainable from 100 to 350 gallons per minute, according to the gauge head. The pump is constructed in gunmetal with a stainless steel spindle, and 'a radial thrust bearing which serves to locate the impellers deals with any small-end thrust which might arise. A roller type main bearing is used, situated in a bracket carrying the thrust at the coupling end of the pump, whilst the tail end of the spindle runs in grease-lubricated bearings of ample length formed in the suction passage.
Water for cooling the engine is circulated from the pump to the engine jacket, draining off through a large overflow pipe in the radiator. A non-return valve between the engine and the pump prevents the engine cooling water being accidentally drained, and there is a special filter incorporated in the circuit.
The fire pump can be primed by means of a patent rotary exhauster driven through a frietion drive from the pump spindle and only engaged when required. The body has ample accommodation for all the equipment necessary in fire fighting. The main hose box will carry at least 2,000 ft. of canvas delivery hose, easily accessible from either side. Four. 10-ft. lengths of 4-in. armoured rubber-lined suction hose with screwed couplings are carried below the footboards, one end of one of the hoses being equipped with a basket sieve. Large lockers are fitted for carrying hydrant stand pipes, hydrant keys, adapters, extra branch pipes, jets, etc. Other boxes accommodate tool kit, jacks and the light:ing accumulator, whilst the spare wheel is housed in a special compartment underneath the rear running board, being very quickly accessible. A two-gallon foam extinguisher and two Pyrene extinguishers are included in the equipment, whilst there is an instrument board at the rear over the pump, the front driving dash accommodating the usual instruments required to be within the view of the driver. 'Where a small extensicn ladder is required, a 30-ft. Ajax 'pattern is supplied, suitably mounted on rollers supported by brass rods at each end of the hose box.
The vehicle is well sprung and i. mounted tippet 32-in., by 4-in, pneumatic tyres, twins -on the rear wheels, a mechanical tyre pump being driven off the timing gears and provided with sufficient flexible tubing for reaching either front or rear tyres. The frent-wheel brakes are of the Rubery type operated by a vacuum servo motor, front and rear brakes being applied simultaneously by the pedal.