Secondary winding

“ To understand compound winding we must first understand two other methods of winding. In the series winding [106] (Fig. 49) , all the current generated in the armature flows through the coils of the field-magnet. There is only one circuit. The same current flows through the coils of the magnet and through the outer circuit, which may contain lights or motors. Such a dynamo is commonly used for arc lights. It will not regulate itself. If left to itself it will give less electrical pressure when more pressure is needed. ”

“ If the ratio of the winder is 5 to 1, that is if the rubber is twisted five times to every revolution of the main wheel of the winder, 100 turns of the winder will be sufficient for the first trial. This propelling power can be increased as the trials proceed. When the winding has been accomplished the rubber hooks should be detached from the winder hooks and attached to the hooks at the front of the side members as shown in the diagram. ”

“ Wind the Motors Slowly, especially after the first row of knots begin, as it puts the rubber to the least amount of strain by doing this. Quick winding not only strains the rubber but makes the knots form in bunches, and uneven winding, of course, produces an uneven unwinding. ”

“ Figs. 375 and 376.—Single layer and double layer barrel winding. Barrel winding is a method of arranging the ends of armature coils as they pass from one pole to the next, in which, instead of using involute or butterfly connections, V-shaped end connections are used which lie on a cylindrical surface, which is a continuation of the armature surface. The coil ends must of necessity be arranged in two layers, but the method may be used for either one or two coils per slot, the difference in arrangement for these is here illustrated.
340
Barrel winding has been very widely adopted. ”

“ Evidently, if the spring is strong enough to more than lift the leg, a loss of power will159 result, since the rider would have to hold it in check even in coming up in order to keep it from stopping with a bang, as is sometimes noticed when he jumps from a treadle machine. The winding and unwinding of the spring involves no loss of power except in heat incident to motion and imperfect elasticity, which is quite small. ”

“ In the larger size machine they are of the single type. The illustration shows plainly the characteristic feature of barrel winding, namely the oblique end connectors carried out on the extended drum.
Bastard Winding.—In this type of winding, the end connectors project from the inductors in straight lines parallel to the shaft and then are bent inward. It has the 341 effect of being somewhat shorter than the barrel winding. In order to secure better ventilation, it is usual to combine a bastard winding at the rear end of the armature with a barrel winding at the commutator end. ”

“ A concentrated winding is one in which the armature has only one tooth per phase per pole, that is, the number of teeth equals the number of poles. A concentrated winding of the half coil type has only one side of a coil in each slot as in fig. ”

“ The maintaining power for keeping the clock going while winding is peculiar and probably unique. None of those already described could have kept in gear long enough, maintaining sufficient force all the time, as that part takes 10 minutes to wind, even if the man does not loiter over it. This is managed without a single extra wheel beyond the ordinary winding pinion of large clocks. The winding wheel on the end of the barrel is close to the great wheel, and you see the pinion with the winding arbor in the oblique piece of the front frame of the clock. ”

“ WINDING-TACKLE PENDANT. A strong rope made fast to the lower mast-head, and forming the support of the winding-tackle.
WIND IN THE TEETH. Dead against a ship.
WINDLASS [from the Ang.-Sax. windles] . A machine erected in the fore-part of a ship which serves to ride by, as well as heave in the cable. It is composed of the carrick-heads or windlass-heads, which are secured to all the deck-beams beneath, and backed by long sleeper knees on deck. The main-piece is whelped like the capstan, and suspended at its ends by powerful spindles falling into metal bearings in the carrick or windlass heads. ”

“ Its action may be compared to that of a wheel, which, running down a hill, acquires sufficient momentum to carry it up another. There are several toys which owe their operation to the same principle, of which we may particularize the windmill, whose fliers are pulled round by a string affixed to the axis of the sails. In playing with the bandilor, a certain address is required to prevent the sudden check which the toy would otherwise receive when it arrived at the end of the string, and which would necessarily so destroy its momentum as to prevent its winding itself up again. ”

“ If the rubber strands are divided they wind up many more turns than when combined in one bunch. If eight strands are twisted together you cannot turn as many times as with four strands. Fig. 260 shows a one to one gear and its connections, and Fig. 261 a gear with a greater ratio.
A gear of one to one might be placed at the opposite end of the framework from the propeller, thus extending the number of revolutions in that manner, the second rope or motor extending back and below the first, Fig. 262.
Fig. 262. ↑
Winding Devices. ”

“ The object of this winding is to check any tendency toward hunting when the alternator is to be run as a synchronous motor, either for rotary condenser or power service. The amortisseur winding consists of heavy copper bars, placed around and through the pole faces and short circuited at the ends by heavy copper rings; it serves as a starting winding to bring the rotor up to speed as an induction motor, and also serves as a damping device to neutralize any tendency toward "hunting" caused by variation in speed of the generator supplying the current. ”

“ Other systems of winding have been introduced with only partial success, the principal one being a modification of drum-winding: a tube on which the yarn is wound rests horizontally on a revolving drum, the thread traverses the width of the drum, and thus a bobbin is built up, having level edges sufficiently firm without any protecting flanges. ”

“ Winches Iron Are Handles for turning round Grindstones, Wheels of Chain Pumps, &c. Wind Bringing a Ship's Head about, is called Winding of her, and when rides at an Anchor, she is said to wind up. Also when she is under Sail, they use to enquire, How she Winds, that is, which way she lies with her Head; so, to Wind the Boat, is to turn her Head about. Wind Taught Implying as much as stiff in the Wind, for a Thing is Taught, when it is stiff. Thus too much Rigging over Head, or any Thing holding Wind Aloft, is said to hold a Ship Wind Taught ”

“ The current flowing in the primary winding causes repeated reversals of magnetic flux through the iron core. These variations of flux induce pressures in both coils; that induced in the primary called the reverse pressure is opposite in direction and very nearly equal to the impressed pressure, that is, to the pressure applied to the primary winding. Accordingly the only force available to cause current to flow through the primary winding is the difference between the impressed pressure and reverse pressure, the effective pressure. ”

“ The governing is entirely automatic. If the pressure on the wind wheel, which it will be seen is set off the centre line of the mill and tower, exceeds that found desirable—and this can be regulated by means of a spring on the fantail—the windmill automatically turns on the turn-table and presents an ellipse to the wind instead of a circular face, thus decreasing the area exposed to the wind gradually until the wheel reaches its final position, or is hauled out of gear, when the edges only are opposed to the full force of the wind. ”

“ When the wind rises to such a speed as to overbalance the force of the spring each door opens and lets the blast pass through. One collateral advantage of this type of windmill is that it may be made to act virtually as its own stand, the only necessity in its erection being that it should have a collar fitting round the topmost bearing, which collar is fastened by four strong steel ropes to stakes securely set in the ground. The dynamo is then placed at the lower bearing and protected from the weather by a metal shield through which the shaft of the axis passes. ”

“ Although it may never be known to whom the world is indebted for the windlass, there are circumstances which point to the construction of wells and raising of water from them, as among the first uses to which it as well as the pulley, was applied. The windlass possesses an important advantage over the single pulley in lifting weights, or overcoming any resistance since the intensity of the force transmitted through it can be modified, either by varying the length of the crank, or the circumference of the roller on which the rope is coiled. ”

“ To a model aeroplane enthusiast a winder is an enormous acquisition. The converted egg-beater type of winder, so much in evidence, leaves much to be desired, the chief fault being that the bearing spindles wear so quickly, apart from the fact that they are awkward to manipulate single-handed. ”

“ A windmill consists of a series of inclined planes, each of which forms one of the radii of a circle, or spokes of a wheel, to the axle of which a gearing is adjusted by which the power generated is utilized. The wheel is made to face the wind by the wind itself blowing against a sort of rudder which projects from the axis. The wind blowing against the inclined surfaces or vanes of the wheel causes each vane to move in accordance with the law of component forces, thus revolving the wheel as a whole. ”

“ From Table V it will be seen also that a wind velocity of fifteen miles per hour develops a power three times as great as an eight-mile wind, and a twenty-mile wind is twice as powerful as a fifteen-mile, or six times that of an eight-mile. Hence, a small increase in velocity greatly increases the power of the windmill, while a low velocity gives but little working force. ”

“ It may be stated that the loss of velocity by a given windage is directly as the windage, and inversely as the diameter of the bore, very nearly.
Wind-gauge. In a military sense, is an attachment to the sight (either front- or rear-sight) of a fire-arm by which an allowance for the effect of wind on the projectile can be made in aiming. Though usually called wind-gauge, it is also used to counteract drift or any other deviation which can be anticipated. In the old model target-rifles, the front-sight is capable of a slight movement. ”

“ Dines says:—“It had been assumed in the above that the wind pressure varies as the square of the velocity. The experiments have proved this to be the case, for when upon a calm day equilibrium for any plate is once attained, it has been found impossible to disturb it by any alteration of the velocity of rotation, and since the centrifugal force varies as the square of the velocity the wind pressure must do so also. For the smaller planes the maximum velocity of which the machine is capable is about seventy miles per hour.” ”

“ The windlass is made in a conical form, being a little larger at one end, than at the other; and if the friction of its bearings be relieved by the ordinary friction rollers, it will so far multiply the force applied, as to break a double inch-rope, by the power of one man at the crank. An endless rope, or one of which the two ends are spliced together, is passed five or six times round the small end of the windlass, and down under a single pulley below: then, as the windlass is turned by the crank, the rope is constantly given off from one part, while the circumference is greater. ”

“ When we expose the sails of a windmill obliquely to the gale, we check the velocity of a small portion of the atmosphere, and convert its own rectilinear motion into one of rotation in the sails; we thus change the direction of force, but we create no power. The same may be observed with regard to the sails of a vessel; the quantity of motion given by them is precisely the same as that which is destroyed in the atmosphere. ”

“ The horizontal wheel, on the other hand, occupying a horizontal zone and attached to a shaft that is vertical, like the usual small water turbine, in position (but not in the fluid impact) receives the wind impact upon only some of the vanes at a time—not the whole circumference—with less proportional power and greater complexity of construction. ”

“ Dismissing the old windmill and the æolian wheel as not fully coming up to the mark, M. Plessuer turns to sails as affording a possible solution of the problem. "The utilization of the power of the winds," he writes, "and its transformation into mechanical work are only possible by means of sailing vehicles, driven by wind upon a circular railway, the power generated by such rotation being transmitted to an axle and thence to machinery." ”

“ Outlook. 83: 243. My. 26, ’06. 60w. Kinzbrunner, C. Alternate current windings, their theory and construction: a handbook for student designers and all practical men. *$1.50. Van Nostrand.
The clear and simple explanation of the principles of alternating current windings given in this volume makes it suitable not only for students and designers but also for the workman engaged in the manufacture and repair of alternating winding currents. Chapter 1, treats of The production of alternating currents; Chapter 2, Alternating current windings; Chapter 3, Continuous current windings ”