Motor (machine)

“ The electric motor is a machine which transforms the energy of an electric current into mechanical energy or motion. The direct current motor consists of the same essential parts as a direct current dynamo, viz., the field magnet, armature, commutator and brushes. ”

“ Motors are now used on sewing machines, washing machines, dish washers, vacuum cleaners, wringers, fans, refrigerating systems, pumps, grinders, freezers, churns and separators. They are made either for direct or alternating current. When purchasing a motor, be sure to designate the type of current with which it is to be used. Select motors of the right size to operate the machine. It costs more to operate a large motor on a small device than a small motor. ”

“ The speed and strength of the motor are regulated by the amount of iron and wire upon it, and by the volts pressure and ampères of electricity supplied to the brushes. Motors are made from a small size that will run a sewing-machine up to a size large [94] enough to run a railway train, and are often operated through wires at a great distance from the place where the electricity is being made, sometimes miles away. ”

“ An electric motor of small power—about eighteen kilogrammetres per second—controls the shaft on which the three rotary brushes are fixed, and the customer has only to unlock the machine, the same as all others of its kind, with his coin, and move the handle which opens the circuit and starts the motion. ”

“ The machine gets charged after a few turns of the handle, and the operator feels that, as the charging progresses, it gets harder to turn the handle. In large machines the manual work becomes so heavy that it is convenient to use an electric motor for working the machine. ”

“ With Ned and Bob to help and offer suggestions, Jerry went all over the engine to locate the trouble. It might be in one of a dozen places, for a gasolene motor is a delicate machine and can get more kinds of things the matter with it than can a baby. ”

“ In all the foregoing chapters we have been considering only the muscular engines of the human machine, counting them over and comparing their construction and their mechanism with those of the internal-combustion engine of a motor cycle. But of the levers or crank-pins through which muscular engines exert their power we have said nothing hitherto. Nor shall we get any help by now spending time on the levers of a motor cycle. We have already confessed that they are arranged in a way which is quite different from that which we find in the human machine. ”

“ The motor used for driving has several coils in the armature connected with slip rings, from which an alternating current may be tapped off; the motor acting partially as a generator, besides doing good work as a motor in driving the machine. This alternating current is conducted to a frequency meter, which consists of a powerful electro-magnet, over which are placed magnetised steel springs, having different natural periods of vibration. By means of a regulating resistance the motor is run until the spring which has the same period as the desired armature speed vibrates freely. ”

“ The clockwork motor M, Fig. 51, should be capable of running for several hours with one winding, and powerful enough to take up the work of driving the machine without any appreciable effort. The main spindle of the motor is so arranged that it makes one revolution in two minutes, and the reduction in speed between the motor shaft and the shaft to which the coupling A is attached is 30:1. ”

“ An electric motor can be turned into an electric generator by simply reversing the direction in which the armature rotates—that is, any electric machine is either a generator or a motor. This fact can be illustrated by means of Figs. 13 and 14, both of which show the armature and the poles of the field magnet. The first figure represents an electric motor, and, as can be seen, the pull between the N pole of the armature and the P pole of the field is in the direction of arrow b, hence the armature will rotate in the same direction, as indicated by arrow a. ”

“ Method of Starting a Motor.—Although motors and dynamos are practically similar in general construction and either one of them will act as the other when suitably traversed by an electric current, there are certain differences between the connections and accessories of a machine operated as generator and one employed as a motor. For instance, when a machine is operated as a dynamo, it is first driven up to speed until it has excited itself to the right pressure, and then it is connected to the circuit ”

“ If it is required to turn a lathe or other machine by power at any given place, it will simply be necessary to convey to that place two wires to conduct the current, and then attach a motor. Although heavy, a motor is compact, and a man can, without difficulty, move from place to place, on a properly-designed truck, such a machine up to the size of say ten horse-power. ”

“ The motor of a steam vehicle always stops when the machine is not moving, which is another distinguishing feature, as the gasoline motors run continually, or at least unless the car is left standing for a long time. ”

“ Furthermore, a wider belt can be employed than on cone drive machines. As a result, a maximum amount of power is delivered to the machine pulley, and is transmitted through heavy gearing to the spindle, under all conditions, thus fitting this style of machine particularly well to the heavier classes of work. Another advantage of this drive is its particular adaptation to the application of a motor. The constant speed type of motor, which is more economical, both in first cost and in the amount of power consumed, than the variable speed motor, can be employed. ”

“ So when the motor is required to do increased work, the machine slows up; but with this slowing up, the counter electro-motive force decreases, and consequently the current passing through the motor increases.
39 As with the dynamo, one of the marvels of the motor is its efficiency. In perfect machines, ninety to ninety-five per cent of the electrical energy supplied can be converted into mechanical energy. For this reason it has become a competitor with, and even successor of, steam in countless cases, and especially where water-power can be commanded. ”

“ It is natural that a machine which gives out electric energy when driven by an external power, should, when electric energy is delivered to it, reverse its action and give out mechanical power and do work.
Perhaps the simplest way to explain the cause of the movement of an electric motor, when supplied with a current, is to compare its action to the well-known attraction of unlike poles or magnets and the repulsion of like poles. ”

“ The evolution of the electric motor followed, as a natural thing, from the evolution of the dynamo, for a motor is simply a dynamo reversed. In the dynamo you revolve the armature—as the coils that move between the magnets are called—and the machine gives out current. ”

“ In placing the motor you must be governed largely by the shape and construction of the flying machine frame. If the bulk of the weight of the machine and auxiliaries is toward the rear, then the natural location for the motor will be well to the front so as to counterbalance the excess in rear weight. In the same way if the preponderance of the weight is forward, then the motor should be placed back of the center. ”

“ The first horseless machine was encumbered with levers, pedals, handles and wheels necessary for its guidance, and with taps and grease-valves to turn, which were indispensable for the functioning [90] of the engine. Now, each generation of motor-cars has dispensed with these more and more completely. One by one, almost all those handles have disappeared which require the incessant intervention of man. ”

“ There will now be a difference of pressure in favor of the machine which is driven, and it will deliver a current through the other machine and run it as a motor. The speed of the motor will continue to fall until the difference in pressure or electro-motive force between the two machines is only sufficient to cause the flow of enough current to keep the motor running against whatever frictional resistance, and other resistance there may be. ”

“ With our present knowledge of alternating currents it is useless to attempt to calculate from the simple though misleading assumptions ordinarily made, the output, conditions of maximum work, &c., of this machine. Experiment alone can determine its value, and one properly conducted and interpreted set of experiments should enable us to judge both the merit of the invention and its best possible form. I cannot see, however, how, in the form described in the last issue of this journal the motor can work under conditions of a suddenly varying load as satisfactorily as continuous current motors. ”

“ First, the ordinary individual who buys a motor cycle will not make a careful study of the manner in which the machine is built and how it works, but prefers to tackle it on the 'hit and miss' plan and learn by hard knocks and experience. Second, carelessness and the disinclination many persons have to take proper care of a piece of machinery. A motor cycle, however, cannot be expected to run properly unless it receives regular attention. ”

“ The fifth machine was a big grindstone and the sixth was an emery wheel. The boys had a long discussion, running through several days, on the question whether these machines should be belted to the counter shaft, and thus get power directly from the water-wheel, or whether each machine should be operated by an electric motor attached to it. ”

“ Lieutenant Cameron had declared.
Matt laughed.
"Why, Cameron," he answered, "I used to work in a motor plant, in Albany, New York."
"That may be, Matt, but building a motor is a different proposition from building a flying machine."
"Traquair laid down the plans. All I have to do is to follow them. It's really very simple. An aëroplane, you know, is nothing more than two oblong pieces of canvas, fastened together one above the other and pushed against the air by a motor and propeller. If the motor drives the wings fast enough, they're sure to stay up." ”

“ Constant Speed Drive. The invention of the gear type of drive, or, as it is better known, the "constant speed drive," is, without doubt, the most valuable improvement in design brought out in many years. It is the result of a demand for a machine in which the feeds would be entirely independent of the spindle speeds, and all speeds and feeds would be self-contained, thus doing away with complicated overhead works, or permitting the machine to be driven by a constant speed motor. ”

“ The owner of a motor cycle who expects to use it constantly without previous experience, and not run up against various sources of stoppage and breakage, will find himself mistaken. A frequent experience is to run the whole gamut of troubles, and thus by actual knowledge having learned to fix all the various parts, the operator is qualified to take care of his machine. ”

“ Then, there were double control wires, running from the levers to the rudder and the elevating planes, so that, if one wire broke (a thing that has caused many an aviator’s death) another would take its place.
For starting the machine from the seat—without having to have some one whirl the propeller till the engine was going—there was an electrical motor, which was a sort of boy of all work. For, when it was through its work as a motor, it became a dynamo, and filled up storage-batteries which worked the big electrical search-light, for use when the machine was flying at night. ”

“ Thus one man puts his motor in the front of his machine, another places it in the center, and still another finds the rear of the frame the best. All get good results, the comparative advantages of which it is difficult to estimate. ”

“ In some practice each line of shafting is driven by a separate engine or motor, so that it may be stopped without stopping the others. This same object may be obtained by providing a clutch for each line. It is obvious that in each line of shafting the length nearest to the driving motor transmits the whole of the power transmitted by the line, and that the diameter of the shafting may, therefore, be reduced as it proceeds from the engine in a proportion depending upon the degree to which the power it is required to transmit is reduced. ”

“ It is desirable, therefore, so far as the shafting is concerned, to place the machines requiring the most power to drive as near as possible to that end of the shafting that receives power from the motor. ”

“ Having magnetized the soft iron in the way described, we now join up the wires to the binding screws, under the base, and, the pulley being fixed on to the axle of the armature opposite to the commutator, the machine is now ready for use. To rotate the armature at a high speed it is necessary to connect the pulley by an endless band with a large, heavy wheel which can be rotated by hand.
For continuous work, as we cannot always be turning the wheel, a small steam-engine or water-motor must be employed. ”

“ Moreover, each series of motors must be mechanically connected to the same work, as that of driving a single dynamo or other machine, because if the loads on the motors of a series vary differently, these motors will not operate at constant speed. ”

“ When the machine had been fastened with a wire to the track, so that it could not start until released by the operator, and the motor had been run to make sure that it was in condition, we tossed up a coin to decide who should have the first trial. Wilbur won. ”

“ The entire Ford organization is interested in keeping every individual Ford car in constant operation, at the lowest possible cost. We have known of much damage done to many cars by unskilled repair men.
Remember that a new machine requires more careful attention during the first few days it is being driven than after the parts have become thoroughly "worked in." The car which is driven slowly and carefully when new usually gives the most satisfactory service in the end. Never start out with your car until you are sure that is has plenty of oil and water. Frequently inspect the running gear. ”