THE TWIN CITY CHASSIS.
Page 19
If you've noticed an error in this article please click here to report it so we can fix it.
Two Models to Carry 2 ton and 31 ton Loads, Partly Built Up From Components ' Produced by Well-known American Manufacturers.
TWIN CITY CHASSIS are products 1, of the Minneapolis Steel and Machinery Co.'s Works. Two models are being marketed in this country, and, as considerable consignments are on the way, besides those already here, immediate delivery can be given of either the 2 ton or 31 ton types. They are being handled in the British Isles by the Twin City Truck Co., Ltd., 61, Gra,cechurch Street, E.C. 3.
The smaller model is provided with a Buda, four-eylindered monobloc engine with a bore and stroke of 4 and 5 ins. respectively. Three speeds forward are provided by the gearbox, -which -is mounted as a unit with the engine and clutch. The gear ratios are top 1 to I, second 1.7 to I, and brit 4 to I.
The clutch is of the dry plate type, which is becoming so popular on a large number of chassis, both in this and other countries. The drive is taken through a two-piece propeller shaft, provided with three universal joints and supported at its centre by a bearing slung from a cross-member to a Clark internal gear dual rear axle, in which the load• is taken by a separate member consisting of a round steel bar curved outeatits centre to allow space for the intermediate bevel gear drive and the axle shafts.. In the Clark axle the bevel pinion, crown wheel, and differential gear are mounted upon Hyatt • flexible Toiler bearings, as also are the wheels at, their inner sides; at the outer sides the wheels are supported on double row radial ball bearings.
Both brakes operate on the rear wheel drums, one being of the internal expanding type and the other of the externat contracting band type.
The frame, which is of very :tout construction, with well guseeted crossmembers and ends, is built up from structural steel—a material which .stood up to its work remarkably well when employed in the frames of lorries built for transport work on the Western Front.
A stout, spring-mounted fender is situated at the front end of the frame.
The torque and braking strains are taken through the rear springs, which ace, strengthened for this purpose. The radiator is of the built-up type with cast header and bottom tank. Pump circulation is employed for the water ; the oil is also 'under pressure. The 34 ton model differs in many
respects from the one just described. It has a Twin City engine with four cylinders cast en bloc, with a bore and stroke of 44E ins, and 6 ins. respectively. This power unit embodies several inter
eating features. It.has.a three-bearing crankshaft with adequate bearing surfaces. The cylinder heads are removable, complete with the valve gear, excepting the camshaft, which is situated in the crankcase. Four valves are employed for each cylinder, and it is claimed that this gives the engine very high efficiency. The cylinders themselves have renewable cast-iron sleeves.
The drive is taken through a dry-plate 'clutch to a gearbox situated amidships, and thence by a cardan shaft to an overhead worm-driven Timken rear axle.
In the case of this heavier model the rear tyres are twin solids, and the wheels are of the cast steel spoked type. Four speeds fqrward are given by the gearbox, which is a remarkably compact component.
Stout radius rods are employed at each side of the rear axle.