Operating devices and speed gear
In Fig. 91 is illustrated an automatic clutch, to take the place ol the usual compensating gear. The upper or ratchet ring is made fast one to each driving wheel hub; the ratchet block is pivoted in the lower ring that is loose, having small motion on the shaft, which is stopped by keys. The small collar and key are fixed to the axle, so that on a straight run both pawl blocks bear in the forward teeth of the hub ring. When rounding a curve the outer wheel gains on the inner wheel, throwing the ratchet block into the position shown in the right hand section of the cut. This clutch drives in the same manner in backing a vehicle, making a great improvement over the old forward rachcts, and a very simple device as compared with the more complex compensating gear that requires a divided and sleeved axle. It is the invention of R. F. Stewart, Pontico Hills, N. Y.
The compensating gear
The compensating gear, so essential to the driving mechanism of motor vehicles, and so difficult to make by amateurs , can now be purchased from the Boston Gear Works, Boston, Mass. Their details are illustrated in Figs. 92 to 95. The sleeve extension on the side is the friction pulley for the band brake. They are made in two sizes—8 inch pitch diameter, with sprocket teeth cut to order, with two
bevel gear wheels and three pinions, and with sprocket wheels, i0 inches diameter, with two bevel gear wheels and six pinions for heavy vehicles. The size and cut of the sprocket wheels, which are fastened with screws to the flanges on the rim, may be varied to order.
In Fig. 94 are shown the details in section of a single chain wheel, and in Fig. 95 the arrangement in section for a two chain wheel. The cuts are scaled to about one-third the size of the smaller gear.
The bevels, L and C, are secured respectively to the hollow shafts, .A/and R. These shafts, which are independent ol each other, are reinforced by the tubing, W, which is held in place by means of the collar, P. The two bevels mentioned are driven by three pinions, E. The cut illustrates only two pinions.
When the power is applied to the sprocket wheel, G, it is equally distributed to the bevel gears, C and L, by means of the pinion, E, and two other similar ones, which pinions in driving do not revolve on the stud, A. These pinions being loose on the stud, A, when one bevel offers more resistance than the other (as in the case of the vehicle turning a corner ), it is obvious that the bevels can adjust themselves according to the resistance ottered, the rubber tires are therefore not injured by skidding.
D and E represent a section of case for holding the parts together.
./is a Iriction sleeve to receive the brake band. As can be seen trom the illustration, the shaft is in two parts, separated by a collar that is fixed to a reinforcing liner tube. When the power is applied to the sprocket wheels it is equally distributed to the bevel gears on the split shaft by means of the interposing pinions. When one gear offers more resistance than the other, as in turning a corner, the two gears can adjust themselves according to the resistance offered, as the pinions are loose on their studs, which are the driving parts of the gear.
The reeves variable speed gear.
In Fig. y6 is illustrated the principles of the variable speed gear as made by the Reeves Pulley Company, Columbus, Indiana , for motor vehicles. Variable speed is one of the important features in motor cycle design. Every motor cycle experimentalist knows that road conditions are constantly varying , and to meet these everchanging conditions it is absolutely essential to have a pliable speed device. This consists of two cones mounted on the motor shaft and two similar cones on the countershaft , both pairs being adjustable laterally on their respective shafts by the bar arrangement shown in the diagram, so that when the cones on the motor shaft are close together those on the countershaft are far apart and vice versa, allowing locked adjustment at all intermediate stages. The specially constructed belt runs between these cones bearing upon the conical surfaces with the beveled edges ot the belt only. When the cones on the motor shaft are forced together the belt is therefore expanded and forced to run on a larger circle around the shaft, while simultaneously the cones on the countershaft are separated, allowing the belt to contract so as to run on a smaller circle around the countershaft.
The belt is composed of a series of leather and iron strips, riveted on to a rawhide base, which enables a powerful grip on the edges witiiout in the least kinking the belt. The central swivel bearings of the operating levers have a screw take-up to adjust the tightness of the belt. A double screw shaft, with a sprocket wheel and chain to a hand wheel, enables the driver to gradually change the speed. This device is in use on gasoline automobiles built by the above company.
A motor tricycle gear.
A very compact gasoline motor and two-speed gear train is illustrated in Fig. 97. It is a French design, made by Dalifol & Thomas, Paris, France.
The main axle, motor and gear-box are bracketed from the tricycle frame shown across the top of the cut. The motor, A, is in a vertical position and provided with air-cooling rib flanges.
The motor-shaft terminates in the female portion of a friction clutch B, the male part of the same B' being carried on the end of a shaft, O, in the same line. On this latter shaft are mounted two friction clutches, C, D, the male portions of which C, D', are controlled by a single lever, K, in such a way that only one of the clutches can be in gear at a time. For the high gear, the two parts of the clutch, C, are brought into contact, the power 0i the motor being then transmitted through the pinion, F, to the large gear wheel, E, on the tricycle axle. . For the low gear the lever, K, is pulled over to the opposite side, thus throwing out the clutch C and bringing the two parts of the clutch D into engagement, and by the same lever arm, K', the ratchet clutch, M, is locked to drive the pinion, J, for the slow gear motion.
In this position the power is transmitted to the wheel, E, through the pinions, G, H, /, and J. The spur wheels, F and J, are always in mesh with the wheel E, they being so arranged that as one is driving the other runs free, and vice versa. The gear is entirely enclosed in a dust-proof case and the whole driving gear reduced to the smallest possible space, with its center of gravity at the driving wheel axle.
A friction clutch motor connection.
A very compact and direct connection from a motor to the compensating gear of a vehicle is shown in Fig. 98. It is the subject of an English patent and shows a very compact arrangement of the operation of the friction clutch by a quick thread-screw and lever. C is an extension of the motor crank shaft, to which is keyed the friction pulley, T,
with a ball bearing at c to counteract the thrust of the quick screw X, which is operated by the lever W. U is the matched friction pulley made fast on the pinion sleeve, O, with a cap bearing on the thrust-screw X. A small helical spring, a, between the end of the crank shaft and the pinion sleeve cap, pushes the clutch open. The pinion sleeve is feather keyed to the crank shaft C1. Y is a nut screwed into the frame, V, forming a bearing for the outer end of the pinion sleeve and for the thrust-screw bearing thread. The compensating gear and box is of the usual construction and well shown in the cut without reference to the lettered parts. It has ball bearings, as shown at R R, and forms part of the driven axle.
A gasoline motor starter.
In Fig. 99 is illustrated a starting device, designed and made by Mr. Estcourt. in England, for the purpose of starting the motor by the driver without leaving his seat. A starting wheel, B, with oblique saw teeth, is fixed on the motor shaft, A. A sprocket chain. C, C, is wound on a
drum containing a coiled spring, D, so arranged as to rewind the chain with a stop, /, so as to allow it to hang free from the ratchet wheel when the finger loop at E is dropped to the eye in the vehicle floor—G, is a small sheave under the floor, in which the lanyard, F, runs—K, is a slotted plate with flanges, or guard, for guiding the chain. For starting, the driver takes the loop, E, or its handle, in hand, first drawing the chain in contact with the teeth of the wheel, makes a sudden pull to the extent of the unwinding ot the chain, and as suddenly returns the handle to the floor, when the chain is wound up by the spring, and stopped just clear of the sprocket wheel. If the motor does not start at the first effort it is repeated.
Steering wheel gear
In Figs. 100 and 101, we illustrate two of a number of designs for setting the steering wheels at right angles to the radius of their respective curves. When a vehicle is in the act of rounding a curve, it is imperative, in order to prevent side-slip, that the axes of all the wheels should radiate from one point; that is to say, assuming the axis of the rear wheels to be fixed, then prolongations of the axis of the two front wheels shoidd intersect a prolongation of the axis of the rear wheels at one and the same point, and this should be
the case to whatever extent the front wheels are turned. By swivelling the steering axle on its central bearing, it may readily be seen that the axle is in line with the radius of the curve that the vehic e is moving over, and that the plane of motion for each wheel is at right angles to the radius of the curve. With this arrangement of the steering gear, the wheels run perfectly free and do not crowd each other with side thrust and cause friction.
When the wheel pivots are placed near to or within the hubs, the axle in rounding a curve, is not parallel with the radius of the curve, the inner end taking a forward position and the outer end a backward position from the radius of the curve drawn through the centre of the axle. It will then be readily perceived that the planes of the wheels do not coincide with the tangent of the curves on which they are running. Hence some arrangement of the controlling parts must be made to vary the planes of the wheel to meet the requirement of their respective radii. The amount of angular change in the relation of the planes of the wheels on a curve depends upon the length of the wheel base of the vehicle, and increasing therewith. In Fig. i00 is shown the ordinary method of giving the wheel on the inner curve a greater movement than the one on the outer curve, when a steering lever is pivoted to any part of the connecting link between the two pivot arms, a, b. The angle of the pivot arms with the plane ol the wheels should vary somewhat with the width of the tread, the wheel base, and the radius of the smallest curve allowed for the vehicle to turn upon. The usual practice is about 30° to the plane of the wheel. With arms at right angle to the axle, as in Fig. i0i, with a bell crank arm pivoted on the axle, the angle of the bell crank should be about 6o°, or twice the angle, as in the first-mentioned arrangement.
The suppression of the noise from the exhaust of gasoline and steam motor vehicles has been a matter of much comment and experiment, which has resulted in a few devices that have so modified the nuisance to both man and beast as to produce only a small hissing noise that is scarcely noticed by equine sensitiveness. A cylinder of about four times the capacity of the motor cylinder, made of sheet iron, and strong enough to sustain ten pounds pressure per square inch, is in common use. It may have two or three perforated disks fastened within and be covered with asbestos felt and an outer covering of duck or tin. The end ol the cylinder opposite the exhaust entrance should also be perforated with an aggregate open area equal to four times the area of the exhaust inlet. The exhaust muffler box, or cylinder, is also made to contain a pipe for heating and vaporizing the gasoline, or for heating the charging air. In Fig. 102 is illustrated a device, made of iron pipe and
fittings, which gives a very free flow to the exhaust. The exhaust pipe terminates at the enlarging socket. The slots in the pipe are cut in a milling machine as thin as practicable , and the cap may be also slotted or drilled, giving a total area of four or more times the area of the exhaust pipe. Another form in which the final exit of the exhaust may
terminate close to the ground is also in use and has its advantages. It is shown in section, Fig 103. A tube or iron pipe one size larger than the exhaust pipe may be drilled with holes equal to four or more times the area of the exhaust pipe and closed with a cap or welded up at the end. An expanding socket tapped through will allow of a larger pipe being screwed therein to direct the final exit ol the exhaust down to so near the ground as to make it unobservable. If such a pipe is attached to the cylindrical muffler first described the exhaust may be made practically noiseless.