The Peerless Chassis.
Page 7
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A Range of Models for Three, Four and Five-ton Loads.
There is a term the use of which is customary in descriptions and specifications of constructions the design of which is the care of mechanical engineers interested in what is called, for want of a better name, general engineering work. These are often referred to as being " massive in construction." During our examination of an example of a Peerless chassis recently, we were frequently reminded of this term. It applies in the same degree to all the various components of the chassis, to the engine as well as to such minor parts as control levers. The chassis throughout is full of features illustrating that individuality which is a characteristic of sound engineering design.
Long-stroke Engine and Unusu. ally-large Crankshaft.
The engine, a four-cylinder, is, for a commercial-vehicle chassis, a long stroke motor, its dimensons being 4-1ins, by 6 ins. bore and stroke respectively. The cylinders are cast in pairs, and, again an unusual point, are of the T-headed type. The inlet and exhaust valves are operated by separate camshafts through adjustable tappets, and it has not been thought necessary to enclose the valves and springs by the customary covers. The crankcase is made, as is now usual, in two parts, of which the lower half serves only as a receptacle for the oil. The crankshaft is very substantial indeed, the bearings being no less than 2ins, in diameter. The lubrication system of this engine is of the constant-level, splash type. The oil level is maintained by an oil pump driven through the medium of gearing from the camshaft. The carburetter is one specially designed and constructed by the Peerless Co. Ignition is by standard dual Bosch, and the water circulation by a gear pump situated on the near side. The control of the engine is by two levers on the steering wheel and by accelerator pedal. The maximum speed is limited by means of a governor which when set is locked and sealed. A unique feature of the control is that it is impossible to start the engine with the ignition lever in the fully-advanced position, as in such circumstances a steel plate is interposed between the end of the crankshaft and the starting-handle clutch, thus preventing the engagement until the ignition lever has been retarded, The water circulation, as has been remarked, is by pump. Its cooling is effected by means of a substantial radiator with horizontal gilled tubes. This is further
assisted by means of a large fan, belt driven in the customary manner, with adjustment for the tension of the belt.
Readily Adjusted Clutch Spring.
The flywheel struck Us as being unusually large and of exceptional width. It forms the female portion of a leather-lined cone clutch. The spring for this is so arranged that all the thrust is self-contained. The adjustment for this we consider is more than usually simple and accessible. A commendable feature of the clutch-operating gear is that the fork operates on a large ball thrust bearing, and as a consequence ease in operation and the minimum of wear in this part should be the user's experience. Behind the clutch is found the customary two-jointed propeller shaft, which transmits the power to the four-speed-and-reverse gearbox.
To this component even more than to the rest of the chassis can the term " substantial " be applied. The gears are 1 ins, wide, and of fives pitch. The shafts, too, are considerably larger than is usually the ease. Self-aligning ball bearings are fitted. The gearbox case contains also the main-drive bevels and differential gear. From tlifs latter are taken the two halves of the cross-shaft, which project from stuffing boxes at the sides of the gearbox. Their outer ends are carried in self-aligning double-row ball-bearings, housed in heavy cross-shaft brackets, which also serve the purpose of carrying the front shackles for the rear springs.
Carefully-designed Brakes.
Keyed to the outer end of the cross-shafts are plates between which the chain sprockets are clipped and fastened by bolts. From these sprockets the drive to chain wheels on the rear road wheels is taken in the usual manner by roller chains. Well-designed girder radius rods with split-nut adjustment take the thrust from the road wheels to the cross-shaft brackets already referred to. By means of the adjustment mentioned, the tension of the chains can be readily set to any desired amount. The braking system of this chassis is in keeping with the remainder, in that it is most thorough and efficient, and furthermore even to the ininutest detail affords evidence of careful thought and of sound engineering design. The foot brake takes effect on two drums of large diameter, one on each portion of the cross-shaft. This brake is fully compensated. It takes effect through the medium of contracting bands which are lined with fibrous material which is readily replaceable. The emergency or hand brake acts, as is usual, on drums bolted to the rear road wheels. The shoes are of the internal-expanding type, and these also are fitted with renewable liners of fibrous material. They are totally enclosed, and protected from the effects of grit and moisture. The road wheels are of the artillery type, mounted on taper roller bearings.
The frame is constructed of heavy, rolled-steel channels, well gusseted, and in the case of the side members trussed. The equipment includes the driver's seat, speedometer, three oil lamps, horn, complete set of tools, pinch bar and five-ton jack. Although the British Government is at the moment taking over almost the whole output of the Peerless Co., quick delivery of a few chassis can be obtained from Gaston, Williams and Wigmore, Ltd., of 7c, Lower Belgrave Street, London, S.W.