Bevel gear

“ At each side of the spur gear are placed bevel gears, meshing into the bevel pinions, one of which is keyed fast to the shaft or axle, while the other is firmly bolted to small pinion that drives the traction wheel, or to hub of the traction wheel, which also runs loosely on its axle. ”

“ On the other, or front end of the shaft which carries the gear, D, is a bevel gear by which another bevel gear and worm is turned. The worm rotates the worm gear, F, in two opposite arms of which are slots that carry pins projecting inwards, which may be moved toward or away from the center. This gear wheel turns free on the shaft that carries the pulley, C, and is intended for opening, by means of the pins in the arms and levers, a cover in the bottom of the hopper and a valve in the bottom of the hulling cylinder. ”

“ Now then let us understand that the crank wheel 5 operates the knitting mechanism of the machine, and the bevel gear 4, through a shaft which runs the entire length of the machine with a series of cams mounted on it, operates the narrowing mechanism. We have seen that the driving parts from the driving pulley 1 on the back of the machine, over to and 116including the large gear 3, and back to and including the small bevel gear which drives the large bevel gear 4 are in motion at all times while the machine is in operation. ”

“ Attached to the trail are the trail spade, float trail handspike, trail handles and the lunette.
Elevating Gear.—The elevating gear is of double-screw type and consists of an inner and outer elevating screw, an elevating-gear bracket, an elevating bevel gear, two elevating bevel pinions, and two elevating crank shafts. The inner elevating screw is a steel screw, threaded with a right-hand thread. It is attached at its upper end by the elevating pin to the rear end of the rocker. ”

“ Needles and Decker
Points Used on the
Automatic Narrowing
Machine.
The method of starting and stopping the narrowing or fashioning mechanism is quite a novel and ingenious arrangement. To explain it we will refer to Fig. 81. The number 4 indicates the bevel gear shown at 4 in Fig. 75, and 4-a is the small pinion a part of which may be seen in Fig. 75. The larger bevel gear 4 has a small space (three or four teeth) cut away so it acts somewhat on the principle of an intermittent gear. When the small pinion 4-a comes to this spot the large gear 4 will of course stop. ”

“ Belt-tightener. A pulley employed to cause a belt to tighten upon another pulley to enable it to transmit motion periodically instead of continuously.
Bevel-sawing machine. A wood-working machine in which the saw or the work table may be set to cut a surface at other than a right angle to the face of the work that rests against the work table or the fence as the case may be.
Bevel-square. A square whose blade may be set to any required angle to the stock that holds it.
Bevel-wheel, or bevel-gear. A gear wheel with its teeth at an angle to its shaft.
Bit. 1. A boring tool. 2. ”

“ As a large gear reduction is thus rendered possible on the back axle, it will readily be understood that the change-speed gear-box may be made considerably smaller than would be necessary for a bevel-driven live axle, where a large gear reduction is not permissible, both on account of its size and because such a gear would be very noisy in its working. ”

“ The driving power being transmitted from front sprocket or gear by shaft tube to rear gear or sprocket, all being suitably secured as above stated to frame upon rear fork rotatably supported by ball bearings connected to the frame and forks.
“This does precisely what has always been accounted to be out of the question and confutes both theoretical and practical mechanics. It is a gear that turns the corner by means of square cut teeth that mesh directly instead of by means of bevel teeth, and we call it a face gear. ”

“ The movement of handwheel is transmitted through shafts and bevel gears to worm and rack. Rack is mounted in pintle bearing, which remains stationary, and top carriage moves about its bearing in center of pintle bearing and bronze-lined slides around the outside of pintle bearing. Traversing scale is screwed to pintle bearing above rack, and pointer is formed on traversing worm-shaft bearing. ”

“ Since the efficient transmission of power through bevel gears requires that they be very accurately placed with reference to each other, and maintained very accurately in this position while they are at work, it was necessary to make the transverse frame very rigid, especially at its extreme ends. ”

“ FIRST COLUMBIA REAR-DRIVER—1888.
As to any kind of construction, whether of frame or of driving parts, there is no trouble when spinning on a stand without a load; the question begins when power is put upon it against a heavy resistance in actual use. A maker who has criticised the bevel chainless more severely than any one else insists that bevel-gears are especially wasteful by friction. ”

“ Gears made of laminated canvas are widely used; they are silent and outwear those made of metal. The development of such gears was brought about by the demand for a positive drive without the clash and clatter resulting from metal to metal contact. The laminated gear absorbs vibrations, eliminates noise, and reduces wear. The laminated material is one-seventh the weight of brass, one-sixth the weight of steel, one-fifth the weight of cast iron and one-half the weight of aluminum. ”

“ The question of gearing is complicated by the fact that the frame of the car oscillates vertically with respect to the axles. Spur-wheels, worm-gear, friction gear, belts, multiple-band gear, and chain-gear are or have been used. ”

“ At each machine sat a human being working with hand, foot, and eye, watching the flashing needle, guarding the margin of the seams, jerking the cloth hither and thither quickly, accurately, watching the spool to see that the thread ran freely, oiling the gear with one hand while the other continued to push the garment rapidly under the needle, the whole body swaying, bending, twisting this way and that to keep time and pace with the work. ”

“ Self-reversing gear, with one belt, two fast and one loose pulleys. The large spur wheel is driven from the bevil gear, and carries the weighted lever past the vertical position by a stop on the face-plate or disc, when it falls over and reverses the belt fork. ”

“ Gears about 5 in. in diameter and beveled will be required. Adjust the first pair of the beveled gears as at F and G. If the wheel shaft is metal, the gear may be set-screwed to the shaft, or keyed to it. If the shaft is hardwood, it will be necessary to arrange for a special connection. The shaft may be wrapped with sheet metal and this metal fastened on with screws. Then the gear may be attached by passing a pin through the set-screw hole and through the shaft. The upright shaft like the wheel shaft is best when of metal. ”

“ For the benefit of those of our readers, who have no previous acquaintance with mechanism, we shall merely premise that a gear is a wheel with a toothed circumference, like watch-wheels, or what in ruder mechanism are known as cogged-wheels; and those gears, known as level gears, are such as have the toothing on the circumference not perpendicular to the plane of the diameter, but at an acute angle to it, so that when two gears of a peculiar degree of bevil are set in contact, a horizontal rotatory movement may be communicated to one by a corresponding perpendicular rotation of the other. ”

“ The imported gear cases are clumsy and heavy, and, being made mostly of metal, are apt to be noisy. The 1898 gear cases of American make are made of a combination of rubber, leather and metal, and are light, noiseless and graceful, and most of the leading makes of the chain cycles for the coming season are built with sufficient clearance to take a gear case. ”

“ By gripping the endless rope between grip wheels (see 1208) the small wheel can be thrown into gear to grip the rope by a lever, cam or screw.
c. Differential gear may be driven from a shaft by belts or gearing. See Sections 84 and 3.
d. Screw gear. Ditto.
e. Rack gear. Ditto.
f. Worm and wheel gear. Ditto.
g. Friction gear is usually driven as No. 1211.
1211. Where the barrel shaft has a slight horizontal movement, so that, by the lever, it can be forced into gear with the friction pinion to raise the load, or into the brake block to sustain the load or lower it. ”

“ By multiplying both numerator and denominator by 4, we obtain two available gears having 24 and 40 teeth, respectively. The 24-tooth gear goes on the spindle stud and, the 40-tooth gear on the lead-screw. The number of teeth in the intermediate or “idler” gear b, which connects the stud and lead-screw gears, is not considered as it does not affect the ratios between gears a and c, but is used simply to transmit motion from one gear to the other. ”

“ When in need of small gears for experimental or model machines the amateur usually purchases them, never thinking that he could make them on his own lathe. A small attachment can be made to fasten in the tool post of a lathe and the attachment made to take a mandrel on which to place the blank for cutting a gear. The frame is made from a 1/2 in. square iron bent as shown in the sketch with the projecting end filed to fit the tool post of the lathe. A pair of centers are fitted, one of which should have a screw thread and lock nut for adjustment in putting in and removing the mandrel. ”

“ The gear on the armature shaft should be as small, and that on the axle as large, as practicable. The intermediate gear should be of such a size that it will close the space between the small gear on the armature shaft and the large one on the axle. ”

“ Furthermore, belt connections are lighter and cheaper than gear-wheel or other rigid and positive connections, and hence the wide application of leather belts for the transmission of power, notwithstanding the slight variations of pulley velocity ratio due to the unequal elasticity of the various parts of the leather composing the belt. ”

“ The wheel is thrown into or out of gear, that is, made to bear on the rail of the chassis or relieved from it, by turning the axle with a wrench placed on the octagonal end. In the direction of the radii of the wheels, but inclined outwards, mortises are placed for the reception of the end of the iron handspikes, by acting on which while inserted the wheels are turned, and the carriage moved back and forth on the chassis. Ordinarily, when the wheels are thrown into gear, the carriage being back, it will run into battery of itself. ”

“ In hand-loom work it is not so objectionable, as there is more spring in the wires, and the heads of the hooks need not be too large, and, besides, the speed is less and the wear and tear not so great; but, even with this, if a hand-loom machine that has been in use for some time be examined, it will be seen that the points of the hooks are considerably worn, and that the edges of the knives are hollowed out like a coarse saw by the friction of the hooks on them. ”

“ To keep the beam truly in its place, which is very necessary, as all the bearings are flat, the recesses for the ends of the studs are formed so as to draw the beam without strain into its true position every time that it is thrown out of gear by the sliding frame. The end knife-edges are adjusted and tightly jammed into exact position by means of wedge pieces and set screws, and the beam is furnished with delicate adjusting weights at its top. ”

“ To save work in drawing bevil gear wheels, they are sometimes drawn in section or in outline only; thus in Figure 244 is shown a pair of bevil wheels shown in section, and in Figure 245 is a drawing of a part of an Ames lathe feed motion. B C D and E are spur gears, while G H and I are bevil gears, the cone surface on which the teeth lie being left blank, save at the edges where a tooth is in each case drawn in. Wheel D is shown in section so as to show the means by which it may be moved out of gear with C and E. Small bevil gears may also be represented by simple line shading ”

“ Double wedge gear.
1495. Governor gear. The rope attached to the cage drives a governor acting on a brake or catch which is thrown into action if the cage gains excessive speed, used in Attwood Beaver’s Patent; American Elevator Co., &c.
1496. Rack and pawl gear.
1497. Cross grip lever gear.
1498. Safety hook to prevent accident from overwinding; the projecting horns A A strike the edges of the plate B, and throw the shackle C at top out of gear.
For hoist doors the best appliance is an ordinary spring lock opened only by a key, the doors being provided with springs to close them. ”

“ Gear-case.—The modern roller chain by makers of repute is so durable that the necessity for a gear-case is not so great as when chains were of inferior quality. But if the bicycle is to require the minimum amount of care and attention a gear-case should be fitted. The Sunbeam gear-case is built into the frame and is oil-retaining, and the chain, chain-wheels, free-wheel and two-speed gear are continually lubricated by an oil-bath. A detachable gear-case is not usually oil-retaining, but serves to exclude grit and mud from the chain. ”

“ He likens his gear, in working, to the familiar breast drill, except that the drill has its teeth somewhat bevelled. If simplicity coupled with great strength and rigidity of frame, together with cheap construction and smooth and quiet action, are attained by this gear, as expected, it will evidently score a point among chainless models; but that straight-cut teeth can interact successfully at all with gears set at right angles or nearly so is contrary to all ideas heretofore, and in the lack of a model for examination we must forbear any opinion. ”