Brake cylinder

“ It might be well also to explain the principle and purpose of the cylinder brake. It is almost impossible to cut mechanical gearing which will run easily and yet be entirely free from slogger. Consequently the revolution of a printing machine cylinder [39] would be more or less jerky unless steadied in some way. This is especially the case when it reaches the stone, and, owing to the pressure applied, lifts a little in the gearing. A recognition of this simple matter will enable an intelligent workman to arrange the brake action with judgment and effect. ”

“ In 1891 a so-called high-speed air brake was perfected, this brake being really a modified quick-action automatic brake. This modification consists of the addition of an automatic pressure-reducing valve connected with each brake cylinder. In the high-speed air brake as applied when the train is running rapidly, the highest possible pressure is applied at once to the wheels, but this pressure is lessened by the automatic pressure-reducing valves as the speed diminishes. This method of applying the brakes is the most effective way of getting the full benefit of their stopping power. ”

“ An instance of the weight reduction obtainable in using six cylinders instead of four is shown in Critchley’s list, for one of the four-cylinder engines developed 118.5 brake horse-power and weighed 1,100 lbs., whereas a six-cylinder engine by the same manufacturer developed 117.5 brake horse-power with a weight of 880 lbs., the respective cylinder dimensions being 7.48 diameter by 9.06 stroke for the four-cylinder engine, and 6.1 diameter by 7.28 stroke for the six-cylinder type. ”

“ In this calculation we have nothing to do with the size of the cylinder or the steam pressure, because the scale beam tells us how many lbs. the brake exerts on the scale, and we treat the brake and brake pulley as levers. Thus by multiplying the lbs. on the scale by the leverage of the brake arm we get the number of lbs. exerted at the centre of the crank shaft, and by dividing this by the radius of the brake pulley we get the number of lbs. on the circumference, or, what is the same thing, the perimeter of the brake pulley. ”

“ The water under each piston is forced into the next cylinder above, so that the rams all travel upwards at proportional speeds, so as to reach the top of their stroke at the same time.
1218. Self-sustaining gear. The revolution of the pinion tends to lift the barrel and its brake wheel out of the brake; lowering is performed by relieving the brake wheel by a lever which raises it from the brake. Cherry’s patent.
1219. Belt hoist. Worked by a loose vertical belt, which is tightened by the lever and pulley when required to hoist, and in lowering a load the belt friction acts as a brake. ”

“ Every car carries at least two brakes of band pattern—one, usually worked by a side hand-lever, acting on the axle or hubs of the driving-wheel; the other, operated by the foot, acting on the transmission gear (see Fig. 48) . The latter brake is generally arranged to withdraw the clutch simultaneously. Tests have proved that even heavy cars can be pulled up in astonishingly short distances, considering their rate of travel. ”

“ For this reason the felt should be wound, starting from the wheel end, in a direction opposite to the forward motion of the wheel, covering the axle for a distance of six or eight inches. The felt should be fastened to the shaft with shellac and bound in three or four places with cord.
While oil on the brake bands is not desirable, oil on all of the bearing points of the brake mechanism is highly desirable. Some time, when driving in a city, take notice of the number of times the brake is applied. Then stop to think how each action is taking place in the brake mechanism. ”

“ As every car is equipped with two distinct sets of brakes, drivers should learn to use first one and then the other on long grades, and this may be helped out considerably by using the motor as a brake—that is, by cutting off the ignition and allowing the machine to push the engine under compression, and even more by engaging a lower gear before cutting off the ignition, so that there is a greater leverage obtained to retard the car. ”

“ The approach of the corves toward the pit mouth was signaled by a bell, brought into action by a piece of mechanism worked from the shaft of the engine. When the bell sounded, the brakesman checked the speed by taking hold of the hand-gear connected [118] with the steam-valves, which were so arranged that by their means he could regulate the speed of the engine, and stop or set it in motion when required. Connected with the fly-wheel was a powerful wooden brake, acting by pressure against its rim, something like the brake of a railway carriage against its wheels. ”

“ Don’t, then, subject your bearings to an unnecessary strain by forcing your motor to labor as it must, if too steep a hill is taken on too high a gear. See that your hand brake can lock your wheels. On a five-mile grade one brake may burn out, and on most cars in this country the hand brake is next to worthless from lack of use and care. Letting the engine act as a brake is a good practice on long descents.
On going through sand or mud that looks as if it might stop you, change into a lower gear and don’t lose your forward momentum. It is easier to keep a car going than to start it again. ”

“ The finisher scrapes superfluous enamel out of the bottom bracket threads, and other parts where bearings, etc., require to be fitted, runs a dummy, or easy fitting tap, through the threads, wipes a little oil on the threads and screws in the bearing cups, fits the axle, cotters on the cranks and chain wheel, inserts the seat bolt, ball head cups, attaches the rear mudguard and brake work, and slips the rear wheel into the forks. ”

“ I made myself comfortable on a grassy slope and proceeded to take the engine down. This I soon discovered was no mean task. It took nearly three hours to remove the cylinders. Woe be unto the man hereafter who puts nuts where they cannot be loosened or places cylinders where they cannot be removed save by an Indian sword-swallower! The result of my investigations was that I found the front piston in fragments, mainly in the bottom of the crank-case. The gudgeon pin was broken in half and the connecting rod was waggling about merrily in the cylinder. ”

“ The brakes vary a good deal on different machines, but on high-class bicycles they are usually operated by Bowden cables and wires which are concealed in the handle-bar and are operated by inverted levers underneath the hand grips. The Bowden mechanism obviates all bell cranks, rods, and other levers because it conveys a direct pull to the brake while passing around angles which are not too acute to prevent free sliding of the wire inside the cable. ”

“ The crank axle is behind the boilers. The levers, the injector, the access to the fire-box, a pedal for working the engine brake as well as a screw brake for the carriage, are all in front. The brakes act on all six wheels, are worked by the driver, and the whole weight of the engine, car, and passengers being carried on these wheels, the car can be stopped almost instantaneously; and as over two-thirds of the entire weight of the car and passengers rests on the four driving wheels ”

“ Another popular type of brake is the roller lever brake. This is usually made up by the cycle maker to suit his own models and consists of a lever placed each side of the handle-bar which rolls or turns in a bearing. At each end of the lever there is a crank which pushes down a rod in communication with the front or rear brake shoes. The handle-bar brakework is usually assembled on the bar ready to slip into the machine in the finishing shops.
Handle-bars are largely bent by specialists, but some firms make their own. ”

“ Caution.—After you have set the gears for starting, and before you release the clutch pedal, always reach and make sure that the emergency brake lever is in the neutral position. New drivers invariably forget to do this, which results in severe strain on the bearings, and causes them to get loose; the average brake band will not stand more than fifteen to twenty minutes of continuous contact before it burns or wears beyond the point of usefulness. ”

“ The simplest way of applying a brake is by muscular force, exerted through a hand or foot lever or through a screw, by which the brake block is pressed against the rim of the wheel or the band brake tightened on its drum. This method is sufficient in the case of most road vehicles, and is largely used on railway vehicles. But the power thus available is limited, and becomes inadequate for heavy vehicles moving at high speeds. ”

“ The ignition may be switched off or on as the occasion requires. Switching it off gives greater braking power. The clutch must be left engaged, and the brakes may be used to help. It is well to use first one brake and then the other in descending long grades, as too long an application of one will cause it to heat and burn the friction material. ”

“ On back pedaling the square shoulders of the cam inclines engage, the clutch ring is moved backward with the sprocket wheel, and cam inclines on the inner side of the ring force a brake ring inward into a hollow conical brake shoe connected with the frame of the machine, and having no rotary movement. The brake shoe thus is forced inwardly into a brake cup and effects the braking by its friction. In this case, as in the former, a general indication of the nature of the device is sufficient on the question whether the latter embodies the former in the sense of the contract. ”

“ An endless hemp swifter, led through blocks with large sheaves, connects the sounding machine and deck engine, and when heaving in is kept taut by a snatch block set up with a jigger. As the wire runs out, the regulating screw of the brake must be gradually screwed up, so as to increase the power of the brake in proportion to the amount of wire out. The regulating screw is marked for each 500 fathoms. In fairly smooth water the brake will at once act when the weight strikes the bottom and the reel stops. ”

“ A clutch which grips too hard will cause the wheels to slide and wear. The brake, also, should not be too positive, but be adjusted to work easily, so that the wheel will stop turning just as the momentum is spent, to prevent sliding. Both brakes should be adjusted alike, or one will grip the wheel fast and the other turn. The gripped tire will scrape along and the pavement cuts the tire like a rasp.
Another set of men forgets that oil and grease and gasoline are the natural enemies of tires. They allow the machine to stand in the garage where there are pools of oil or gas. ”