Points from the New York Show.
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By Our Own Correspondent.'
The annual Commercial Vehicle Show, or as it is called in the U.S., the Truck Show, has now become quite a feature, and each succeeding one serves as an index pointing towards the trend of opinion regarding design and construction. One noticeable feature of this year's exhibit is the general high standard of excellence obtained by the majority of manufacturers. Two years ago, heavy-vehicle design was in a state of chaos. Last year seemed to be the transition period ; this year conclusivelyindicates main features of design.
Copying Europe.
I will not attempt to go into details, except to mention one or two points worthy of interest. General features, distinguishing design in the U.S. from that of Europe. shall be my theme. To the European engineer, who has spent some time in the States, it is very evident that European design le being. gradually adopted—undoubtedly a case of the survival of the fittest. Averages are very deceptive, but it is safe to say that the majority of trucks turned out by reputable makers have now : four-cylinder motors, placed under the bonnet in front of the driver; selective, three-speed or four-speed transmissions; and a final drive to the rear axle, either by chains, or worm, or spur gearing. The days of the two-cylinder, horizontal, opposed motor are over, though there are still some "relics " to be seen among certain manufacturers. The fourwheel drive, the planetary transmiseion, and other freakish designs seem also to have gone the way of the weak, and curiously enough, there were very few modern freakish
designs to take their places. The outstanding features of argument at the show are the strong probability of the abandonment of wood wheels for steel wheels, the very rapid advance that the worm-drive transmission is making, and the adoption of more flexible types of frames.
Concerning Wheels.
The American manufacturer has undoubtedly the advantage over his European brother of having first-class raw material to. make his wood wheels from; in addition he has first-class wheel makers. Climatic conditions are, however, very severe ; and there is also the rapidly-growing scarcity of suitable timber, so that, perforce, their attention must turn to a suitable substitute. There is a wide difference in opinion here as to whether the star-section or the cruciform-shaped spoke should he used, or whether the hollow spoke is more desirable for cast-steel wheels. The hollow-spoke steel wheel has. of course, the advantage that it is more sightly in appearance', is more mildly kept clean and painted, and, in my opinion. will be much more suitable for use with the demountable type of tire, which is coming into gradual use in this country.One of the leading firms (the Timken Axle Cn.1 is showing a hollow-apoke wheel with a hollow box-rim, made out of malleable cast iron_ As the section thicknesaes are kept down very small, this material closely approximates wrought iron, and it will be interesting to see how these wheels behave in actual practice. A number of important steel wheels were shown, chiefly from Switzerland. but the manufacturers of steel wheels in America are very much alive to the situation, and several really first-class domestic wheels were on exhibit.
Tires for Isolated Vehicles.
The tire situation, at present, rather camplicates the wheel question. Many users of trucks are situated miles away from the base of supplies, and, if the pressed-on type of tire is used, it very often involves serious hardship when the time comes for replacement. The demountable tires have sprung. therefore, into very great prominence, and there are really some very good demonntables on the market. There are too, really some very bad ones. The advantages of demountable
tires are, of course, obvious. The disadvantages on small tucks are few, but, on large trucks, it is a question of p-inion; at present, the balance of opinion seems to favour the pressed-on type of tiro as being more suitable.
The Final-drive Controversy.
The worm drive was adopted by the Pierce-Arrow Motor Car Co., for its five-ton truck, over two years ago; and the company has had to face many arguments and much criticism. The makers: of chains, at one time, for example. were exceed ingly bitter in their denunciation of this type of drive. This is now entirely changed; there were several good worm-drive trucks on show, and, in addition, one of the leading manufacturers of axles (the Timken-Detroit Axle Co.) has now made an agreement with David Brown and Sons, Ltd., of Huddersfield, and intends to push the worm drive very strongly in this country, both for commercial vehicles and pleasure cars. Several gear makers are also turning their attention to this type of drive, and they told me that the I inquiries they were receiving from various manufacturers showed that they were keenly alive to the advantages of adopting it. There are some half-dozen trucks this year using the worm drive.
Flexible v. Rigid Frames.
In former years, the American manufacturer believed in making his truck frame just as rigid and strong as possible, contending that by so doing he was able to take up the stresses and shocks to best advantage. Naturally, this made the truck very heavy, and, owing to the very severe road conditions encountered, it did not work out successfully. It is now the accepted belief that the frame must be sufficiently flexible to accommodate itself to the various irregularities, by springing a little under shock, and that it will then withstand such shock better than if it were constructed in a rigid manner. Many of these designs, however, point to an extreme being developed. In one truck, for instance, there are no diagonal braces, and behind the gearbox support, there are practically no cross-members whatsoever.
Lack of Standardization.
Leaving aside standards and general design, we find quite a variance in the sizes and weights of details. This is the more remarkable. as the Society of Automobile Engineers has, for the past two years, been trying to standardize many of the details of the commercial vehicle. As this method of standardization is mostly along the line of averages, instead of from what is found to be beet front actual practice, it is hoped that the leading manufacturers will still retain the courage of their opinions, and will put out what, in their opinion, seems beat. For instance, the size of motor for a given load capacity is not yet settled. There is a journalistic tendency toward the small motor with a many-speed gearbox, but this has not yet been put into practice. With this question is also included the speed of the truck. one well-known five-ton truck having a maximum speed of Eq miles per hour, whilst another, of equal prominence, has a speed of 14 miles per hour. As the motors are approximately the same size, and are governed to the same number of r.p.m.. it is evident that one of these is very much over powered for the work it has to do, and must cause needless consumption of petrol. Of course, the characteristic of the American driver to linger on high speed as long as possible, and his utter 'disregard of gear changes, has a good deal to do with this. Personally, I feel that this idea will disappear in a short time, as the advantage of utilizing the gem-box becomes better understood.
The vertical, gilled-tube type of radiator is catching on. and there are several very neat examples ahown. The upper tank with gills east on, h Is Daimler, seems to be very popular. One firm, by the way, has its tubes fastened in in marinecondenser fashion; using the screwed ferrule and rubber
washer at each end. Spring supports for the radiator are very common, though the simple trennion type has a number of follower&
This question of spring supports is troubling many designers, and there are several instances of engines and gearboxes, and indeed the whole transmission, having various kinds of marinas. Presumably to absorb the road shocks, and to provide certain means of flexibility. It is convenient to state, here, that the auxiliary springs on the front and rear axles are also quite favoured, the helical spring directly between the frame and the axle being the most popular.
For quite some time, the Packard truck was looked enon as being the leading example to follow, and many other designs of details were obvious copies. This is now being departed from, and while the Packard truck remains practically unchanged, there is quite a change in design amongst the smaller makers.
Air Cooling Not in Favour.
One of the old leading exponents of the air-cooled engine (The Frayer-Miller Cu.), which showed a chassis at the 1907 Olympia Truck Show, has now abandoned the air-cooled power plant entirely, and has come out with a series of trucke of new design. Thew trucks are extremely good in many details, and it is worth while noting, that in this country, where one would expect the air-cooled type of motor to be strune, on account of the very low temperatures experienced during winter time, this company has seen fit to abandon this type and to take over the accepted water-cooled type.
A Few Special Lines.
We come now to special exhibits. One or two fire-engines were shown, but nothing of the centrifugal type. The same problem is to be met with here as was met two or three years ago in Great Britain, when the fire-engine industry was confined to practically two firms, until Messrs. Dennis broke in on the bueine.se with their turbine fire-pump. This situation, as I said, exists here, and to my mind it would seem that a modern fire-engine, equipped with centrifugal pumps, and built by a firm which has had large experience, both with fire engines and with motor trucks, should command success. Municipal conditions in this country are nothing like as bad
as the Press represents them to be, and I fully believe that the American public will buy what to them seems beet. The fire-trucks ails:wit are chiefly in the nature of hose-carriers.
One type of truck, or rather road tractor, which has sprung into prominence recently is the Martin tractor. The basic selling idea behind this is that the tractor will take a temcern's horse-wagons, and will draw the loads much more cheaply and much more quickly than a team of homes could. They openly state that the average horse-wagon is not snit able for this service, and contend that, whilst this tractor will cause the horse-wagon to be disabled very quickly, yet, when these are used up, a. wagon much more suitable for tractor purposes can be built. For many conditions, these tractors have a distinct use, and it is certainly very interest ing to see one, drawing a heavy, laden horse-wagon, turn round in a small circle, and, if necessary, leave the load behind, ;led go to fetch another. This tractor has three wheels, and is. I think, open to the usual objections to the three-wheeled vehicle. It also impressed me as having its mechauism very inaccessible. Another special truck shown is the American La France Fire Engine Co.'s truck fitted with the Manly hydraulic drive. This particular hydraulic truck seems to have a fair complication of pipes, pumps, unions, etc. It will un doubtedly give an immense torque at. low speeds, but it would seem that the experience with average gasoline trucks has rendered this feature quite unnecessary. Curiously, in this truck, where ,one would expect to find a small-power engine, actually a 50 h.p. four-cylinder, 5i in. bore by 6 in. stroke motor is used, with a load capacity of five tons, and a maximum speed of 12 miles per hoer. The A. O. Smith truck, manufactured in Milwaukee, is notable in its design on account of the herring-bone type of transmission gearing. This truck is fitted also with a worm-drive rear axle, and the manufacturer claims that, with this complete transmission, extreme silence can be secured. The gearbox contains two shafts, one above the other, the gearing being of the constant-mesh herring-bone type. put into action by means of large dog clutches sliding on the shafts, and, as the face of the gears is very wide, it is readily understood that the wear should be small. I was of the opinion, at first, that these were of the Witerst type of herring-bone gears, but closer inspection showed that they were simply double herring-bone gears. This truck is also distinguished by the fact that the thrust and torque reactione to the rear axle are taken up in a large tube, surrounding the propeller shaft. This tube seems to be welded directly to the gearbox, and the whole construction is pivoted at the front end of the gearbox, instead of at the usual position.
Another worm-drive truck is the Bleir, in which the radiator, motor, gearbox, and actually the rear axle itself are all suspended from a sub-frame, pivoted at the front of the main frame. If readers will think of this construction for a :hart time. they will see that this is practically a tractor design.. the propelling mechanism being on one frame, and the carrying structure being really another frame. The method of working this out, using only two axles, is very ingenious, but the question that first strikes the observer is the very large amount of unsprung weight en the rear wheels.
A few trucks are shown with a rear-axle drive of the Milnes-Daimler type; the Studebaker three-tonner, which is a new arrival, had a rear axle almost identical with the Milnes-Daimler. This truck, by the way, has three distinct sets of brakes, a peculiar feature of two of the sets being that., in order to apply them simultaneously, the driver would have to let go of the steering wheel, and pull on one lever with his right hand, and the other with his left hand. There is one truck fitted with an electric self-starter of the Gray-Davis type. The makers must have had the courage of their opinions, inasmuch as they have provided absolutely no means of starting the truck, other than by electricity. I took this up with the attendant, who seemed to be of the opinion that there was a starting crank somewhere on the truck for emergency purposes, but close inspection revealed no method at. all of using this, until the attendant thought of using a can-opener on the front of the dust. pan in order to allow the starting crank to go in. The gearbox oil this truck is also noticeable on account of its immense size ; in fact, if the gear were taken out and the holes plugged up, it would have made a bath tub of a size usually fouud in country hotels.
Hoisting Devices and Steel Bodywork.
I think what must have struck the European most about the bodies is the large variety of dumping and hoisting devices ehown. Practically every exhibitor has some idea Ise another dealing with rapid means of handling the load. This question is of course, very complicated in this country, on account of the high wages paid even to the labourers, and any method whereby the work of one man can be saved
is sure to be approved. The majority of users have the mechanical dump. operated by gears or screws, but one notable ease, the Pierce-Arrow, has a dumping device operated by hydraulic means—a-rotary pump, driven by the transmission, forcing oil into what is practically an ordinary
hydraulic ram. The piston of this ram is connected by moms of cables to the front end of the body. This device dumps a Joao) of five tons in 10 see. The Mack truck has a device consisting of two roller chains at each side of the driver's cab, geared up to the transmission, and connected by means of two arms to the forward end ef the body. This device is worked out very neatly indeed, and is able to dump the load in some 30 sec. A combination of steel-body and screw-dumping device, either power or hand driven, at the manufacturer's discretion, is shown by the E. G. Budd Co.. of Philadelphia. This device, which is very simple, consists of a cross-shaft, carrying a bevel pinion meshing with a gear wheel, which wheel in its turn is counected to a slow pitch screw, alone which a nut travels, this nut being connected to the body. The Peerless Co. showed a tipping gear of very neat design. also operated from the transmiseion. A word must be said hereas to the American tendency
towards steel bodies. The use of autogeneous oxy-acetylene welding has caused a type of body to be developed in which steel plates and members are used. Pressed-steel or straightsteel sheets are welded together, the whole producing a very smooth and really very strong body: Bodies of all shapes and sizes can be built up in this manner, and several completely-, enclosed van types were shown. It is interesting to note that the stake type, or slatted type, of body can also be produced by this means. The finish leaves nothing to be desired, and
those who are familiar with the beautiful work put into the Pullman sleepers will appreciate what is possible by using steel as a substitute for wood. Other steel bodies shown are of ordinary tank type, suitably braced, of course, to withstand the special conditions imposed by road traction. There is just as wide a diversity of opinion in this country as in Great Britain as to the size and type of body required for different work, and, although several attempts have been made by manfacturers of bodies to standardize this part of the truck, it is now generally accepted that the bodies must be supplied as a sepaiate fluting to be built to suit the purchaser.
Motorbuses Yet to Come.
The omnibus has not yet reached a period of development in this country, but there are signs which indicate that the time is coming when such models must be seriously considered as rivals of the street car and the local railroad. Several firms are looking into this question, and carriage builders and chassis builders are awakening to the fact that there is a future for this section of the industry. The success of the omnibuses in New York has, of course, done much to develop this idea. Taking the show as a whole, it will be SPP-11 that a very high standard of excellence obtains, and the American manufacturer who, two years ago, was very much behind in design, has now come to the front, and there are quite a large number of American trucks which could be_ shown in Great Britain and Europe without any fear whatsoever that they would not rank favourably with their foreign competitors. The Commercial Vehicle Show this year must be pronounced (list ince success. " KURT."