The Design of Commercial Vehicles.
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Are we right in the designs which are being followed, so universally, for commercial vehicles, and, in some cases, for omnibuses? I am not speaking of the mechanical design of the chassis, but, more particularly, of the design so far as it relates to the carrying, and disposition, of its load. Are we not following too closely the steps of the pleasure car, the uses for, and requirements of, which are totally different from those belonging to heavy vehicles, and, are we not losing some of the advantages of mechanical traction in doing this? I cannot help thinking that a careful consideration of the subject will show that we are doing so.
Let us look, first, at the average loot or wagon, or delivery van, of to-day. Let us begin with the small
est type of van on the market (see Fig. 1), and study the design we have at present. Upon a chassis, quite correctly designed for a two-seated car, in which case the weight of the passengers is carried between the wheels, a neat little van body has been erected. It looks very nice, and pretty, from the outside, but what is the practical outcome of it all? Look at the sketch as I have shown it. The driver has to be accommodated, whatever the type of body employed, and, in this case, he occupies just the same space as on the pleasure car, except that useful room is taken out of the inside of the van, or in other words, out of its carrying capacity. The result is that the effective value of the van, from an available capacity point of view, is reduced to the small space behind the driver's seat ; in reality, it is merely carrying about a useless ornamental top! All the carrying capacity that has been obtained by the addition of the van body could, just as easily, be secpred by fitting a box at the back of the scat, as shown by the dotted lines. All the rest of the van is " mere leather and prunella," in fact, little better than ornamentation. Indeed, so far as carrying area is concerned, very few of these little vans contain the cubic space of a large carrier tricycle. The same construction seems to be followed if larger loads are to be carried. In Fig. 2 we have a very common design for one-ton and two-ton delivery vans. Here, we find the pleasure-car chassis again, but with a longer wheel-base. Just look at it for a minute. Draw a vertical line midway between the wheels, as I have shown in dotted lines, and you will see that more than one-half of the chassis length is taken up by the necessary accommodation for the engine and driver, and that this occupies pretty much the same space as upon the small van : a little more, in point of fact, owing to the greater length of engine. The increased wheel-base certainly gives a little more accommodation at the rear, but if the frame were cut off at the back wheel peripheries, and the body built up upon that, the accommodation space for goods would still be very small ; hence, in order to get a reasonably capacious carrying space, the
chassis is carried rearwards in a long overhang, thus imposing the whole load upon the back axle.
Now, as motorists, experience teaches us that in any car in which the weight is overhung to the rear of the driving axle, the tendency to side-slip will be very much increased. Seeing that a delivery wagon has to-day a large amount of town work, the important consideration of overhang ought not to be lost sight of, for there is a still further disadvantage. When turning a corner with an overhang, either of I.ody or load, the projection to the rear swings out beyond the course set by the wheels, and there is the greater possibility of striking something rearwards. This point is, perhaps, but a small one, but it should be taken into considera. tion. We have been told, for years, by the advocates of motor haulage, that one of the great advantages of its adoption to the community is that the space occupied by the horse is saved, and that, for this reason, a given number of motor vehicles will occupy, owing to their shorter overall length, a very much less amount of road space than the same number of horse-drawn vehicles. The result is that a larger number of motor vehicles can be accommodated on the same length of road, with the consequent result that, apart from any specific difference in speed of the vehicles, the average time taken in a journey from point to point will be less. 1Vith the great increase which has taken place latterly in the wheel-base of vehicles, and with the further addition in length, brought about by overhang, very much of this undoubted and very specific advantage is thrown away : the needs of the community should be considered somewhat, since, in this matter, we are all individually affected.
There is still another disadvantage in present design, and this I consider to be one of the worst. All motorists are accustomed to inveigh against the vagaries of the covered
van, i.e., the covered horse-drawn van, because it is a fact, which is constantly being impressed upon us all by experience, that the man within the hooded van hears nothing, and sees nothing, but that which is directly in front of him, the result being that he blocks up the available roadway. We may hoot, and hoot, and hoot, until we are tired, before the sound can reach his ear, which will make him clear the road for us, and, as most of us know by experience, when we think he is aware of our presence and is making a way for us, and we draw up alongside, he suddenly swings out again and, if we are not very careful, trouble ensues. Yet in our own commercial wagons we are following exactly the course which we so heartily condemn in others! We are putting our driver inside a box, open only in front, and, moreover, we are putting him in juxtaposition to machinery, which makes more noise than is made by anything on a horsed wagon, so that we fill up his ears, to start with, with a certain amount of sound, which prevents, effectually, any additional noise which might, perchance, by creeping around his surroundings, reach his comprehension ! Are these not all disadvantages, and some of them serious ones, in our present iollow-my-leader system? But is not the chief one that which, with the same space occupied on the road and in the shed, deprives us of a serious amount of carrying capacity, which could otherwise be made available?
How to remedy matters is the question, and here, I think, we may take a lesson from the despised methods of our ancestors—the horse-using fraternity. In Fig. 3 we have the design most commonly associated with horse-drawn vans. Here we have the same general design, so far as the body itself is concerned, as in Fig. a; that is to say, we have a large box, with doors at the back, open in front„, and containing the driver's accommodation within it. Perhaps you will say that, by adopting this body, we have already availed ourselves of the experience of our forerunners; but we have only taken a portion of the design they had evolved, and we must remember that the evolution of the horsed vehicle has been the work of many centuries. What we have done is, as I have shown above, to take the body of the delivery van, as designed for the horsed car, and to put it on a pleasure-car chassis in place of passenger scats. If we look at Fig. 3, we shall see that virtually
the whole of the weight is carried within the wheel-base, and that the rearward end of the frame, or chassis, of the van does not project beyond the periphery of the rear wheels, and we also find that the driver is brought very nearly over the guiding wheels. Of course, the horsed-van designer has not an engine to deal with, and this, it may be said, is a difficulty when designing a motor vehicle, but I think I shall be able to show that this should present no difficulty. If we turn to Fig. 4, we have the design of horsed van in which the greatest possible carrying area is secured for the road space occupied, viz., the furniture van, and, if we come to consider it, this is, after all, what we, in designing motor vehicles, have in view ; that is to say, to obtain the greatest capacity. A wagon, to give the greatest benefit, both to users and the public, should occupy as small a space as possible on the road, and should carry the largest amount of goods that can be placed upon it. In the case of a furniture van, the driver simply sits on the top of the van, and has a projecting footboard in front of him. Here, absolutely no space is wasted whatever, and, what is more, the driver is in a position which enables him to see all that is going on around him : he is equally cognisant of what is coming up behind, as he is of what he is overtaking, though he doesn't overtake much with a furniture van !
If we look at the horsed omnibus, we shall see also that the same broad design is followed, viz., that the whole of the space between and over the wheels is utilised for the carrying of the passengers, in other words, the load—it is quite immaterial whether this consists of living people or dead goods—whilst the driver is placed in front on a bracket seat, occupying a similar position to that on a furniture van. Would it not be more correct, in designing our commercial motor and public service passenger vehicles, if we were to take the whole lesson, instead of half of it, from those who have gone before, and, so far as design is concerned, instead of merely taking a pleasure-car chassis, and putting a box body on it, if we were to re-arrange matters entirely, so as to obtain the largest possible carrying caprcity upon the shortest practicable chassis? Should we not be gaining a point? Of course, we have to find room for the horse;
bat is to say, for its equivalent, the motor, but this need not interfere very much with our arrangements. , There are two ways in which we can carry out the design and achieve. the objects we have in view. In the first (see Fig. 5), by keeping the engine as at present, we can build our box body flush with what is now the dashboard, by which means we shall obtain quite as much carrying capacity, with a vehicle in which there is no overhang beyond the. wheels, as we should with one having a long overhang. We should save the space occupied by driver's seat and footboard, and utilise this area for the carriage of our goods. The driver can easily be placed beside the engine. With the ordinary construction of the day, there is ample room for him alongside of the engine, between it and the offside driving wheel. In this particular, the Lanchester Company, in its pleasure cars, has already shown us the way. This company's new zoh.p. car has two seats, one for the driver and one for the passenger, placed one on each side of the engine, and experience shows that this is not inconvenient, nor does this design make the engine less accessible.
The foregoing arrangement might, very well, be adopted in our omnibuses, too, as it would save very valuable carrying space. Some of our motor omnibuses are to-day built without overhang, excepting that required for the platform and the stairway supports, but, even with those which have not this presumed defect in construction, there is still the loss of valuable carrying space in the 3 feet 6 inches or so. which is devoted to driver's seat and footboard, whilst, as. the driver has not constantly to be jumping down, but sticks to his post the whole time he is out with the omnibus, there is no possible reason why he should not be seated alongside his engine, and, in this position, too, he would be better placed to know what is overtaking him than he is, as now, tucked in beneath his shelter. Or, if we do not care for this method of meeting the difficulty, we can place our driver over the engine, carrying his seat high up on the front of the van (see Fig. 6), or even adopt the same position as on the furniture van, putting him entirely on the top of it. With the usual length of the modern four-cylinder engine, however, there is nothing to be gained by this. Placed as suggested, the driver would be well clear of his engine, which could be got at, by lifting the bonnet, as readily as it is to-day, and steering could be done by a vertical, instead of by an inclined, wheel. This position, too, would place his head and shoulders above his vehicle, so that he would be in a better position, even than in the sketch shown in Fig. 5, for obtaining a full knowledge of his surroundings, and the result, I think, would be to make the vehicle, in this respect, safer and less of a nuisance to the public.
So far as the protection of the driver from the weather is concerned, it may be argued that, in the positions suggested. he would be entirely unprotected. But so is the driver of every other form of vehicle except the covered van, and, candidly, I do not think that drivers get much real protection from the overhanging top of a motor omnibus, or from the front overhang of a van, as is witnessed by the frequency with which they may be seen, during wet weather, shrinking behind a suspended tarpaulin. They should be prepared for the weather, like the drivers of most horsed vehicles and all horsed buses are to-day, but, if protection is desired, it will be quite easy in both cases to provide it in the shape of a hood. On a vehicle designed as Fig. 5, this would take the form very much of the hood of a bathing machine, and would give very complete protection.. In the case of a vehicle designed as Fig. 6, the hood would attach at the top of the seat, and would be very similar to the hoods already used upon two-seated cars : if made with transparent panels, very little interference with an all-round vision would be produced. I do not know whether motor-wagon designers generally have given thought to the subject in the direction I here indicate, but, if they have not, it may result to the general good if they will do so, and evolve wa9r,ons more on the lines suggested than upon those now accepted.