STEAM CAPSTAN-STEAM WINDLASS.
In modern vessels, steam power is made available for handling the capstans or other appliances used for weighing anchor, to the great saving of labor.
H. J. Johnson’s patent capstan, Plates 96 and 97, is the one now fitted on board the U.S.S. Lancaster and other vessels, and may be described as follows:
Fig. 442 is a side view of the entire machine. Fig. 443 is a top view of the machine as it appears after the removal of the capstan, wild-cat, and deck on which they are placed. Fig. 444 is a vertical section, on line x x of Fig. 445, of that part of the machine below the deck on which the capstan is placed; and Fig. 445 is a top view of the bed-piece for supporting the cylinders, the lower end of the capstan-spindle, and the independent gear-shaft.
In said drawings, A represents the bed-piece of the machine. It is a bell-shaped hollow casting, formed with a bottom flange, A’, provided with a series of holes to receive bolts to secure it to a ship’s deck. There is formed upon two sides of said bell-shaped casting, A, large lugs, A2, made with the vertical outer face of each set at an angle of ninety degrees to the other; and to these lugs the steam cylinders B are bolted, and thus remain suspended. From the side of the bed-piece, A, there is also projecting, one above the other, two large brackets, A3, to support the two bearings,a3, of the vertical crank-shaft, C, of the engine. Its crank portion, C’, being close to and between the two brackets A3, is thus properly sustained. The lower end of the crank-shaft, C, rests in an adjustable step, a‘, secured to an extension of the bottom flange, A’, of the bed-piece. The upper end of the crank-shaft, C, is retained in bearings in a bracket, D, secured to the top of the upper one of the brackets, A3. This bracket, D, also carries the bearings for the lower end of an independent shaft, E, placed directly above and in line with the axis of the crank-shaft, C. The upper end of the shaft, E, is retained in bearings supported by a bracket, F, that is bolted to the under side of the deck-beam, G.
The capstan-spindle, H, to which is secured the capstan, H’, and the wild-cat, H2, is retained vertically by bearings,
|I, in the top of the bed-piece, A, and has its lower end supported in a bearing-step, I’, attached to transverse ribs in the interior of and forming part of the bottom of the bell-shaped bed-piece, A. Upon the capstan-spindle, H, there is placed directly above the top of the bed-piece, A, the large gear-wheel, K, having the lower end of its hub resting upon the bearing, I. This gear, K, has a long hub or sleeve, K’, attached thereto, or preferably cast therewith, and the upper end of this hub carries a pinion, K2, to mesh with a large gear-wheel, L, secured to the independent shaft, E.The gear, K, pinion, K2, and connecting hub, K’, are mounted loosely upon the capstan-spindle, H. and are, free to turn thereon at a different speed from the latter.|
Upon the hub of the large gear-wheel, L, there is mounted, or preferably cast therewith, a pinion, L’, keyed or otherwise secured to the shaft, E.
The rim-wheel, M, is connected with its hub, M’, by means of slightly-tapering keys, N, inserted in perforations, m, made correspondingly in the inner periphery of the rim-wheel and the outer periphery of its central portion or hub. When the keys, N, are removed, the central portion, M’, is disconnected from its cogged rim, and will revolve with the capstan-spindle, H, when the latter is rotated by turning the capstan and its wild-cat by hand, while the engine and its train of gears remain stationary.
The crank-shaft, C, carries on its lower portion the eccentrics, c, operating the slide-valves of the engines. It carries also, near its top, the pinion, P, that transmits the rotating motion of the crank-shaft to the transmitting gear, K, running loosely around the capstan-spindle, as above stated, and motion is transmitted from the pinion, K2, on the hub of the gear, K, successively to the gear-wheel, L, pinion, L’, and rim-wheel, M, and through the hub, M’, of the latter to the capstan-spindle when the keys, N, are in position, the power of the engine being multiplied according to the relative size of the gear-wheels and the pinions gearing with them.
The engines are made, as shown in the drawings, to be operated with slide-valves, and have a reversing-valve attached, and other appliances commonly used in steam-engines.
From the description, it is evident that the general action of the steam capstan is similar to that of an ordinary hand capstan. But one chain can be hove in at a time. In case of there being no steam up, the removal of the keys, N, place the capstan at once in condition to be revolved by the usual capstan-bars shipped in the pigeon-holes, V, V.
Steam Windlass. Instead of a steam capstan, some vessels are fitted with Sickel’s Power and Hand Windlass.
The following description and accompanying drawings
|show the steam windlass as now fitted on board the U.S.S. “Trenton,” Plates 98 and 99Figure 446 represents a top view of the windlass. Fig. 447 represents a vertical section through the main gearwheel and the wild-cats or ribbed pulleys. Fig. 448 represents a rear elevation of the windlass and its connection with the steam-cylinders. Fig. 449 represents a side elevation of the same, partly in section, to show parts in the interior of the frame. Fig. 450 represents, in perspective, one of the keys used to connect the main driving-gear with either of the wild-cats. Fig. 451 represents a portion of an anchor chain, with a shackle uniting two sections of chain. Fig. 452 represents, in front view, the main steam and automatic pressure-regulating valves and spring-valve, and the indicator of tension upon the anchor chain. Fig. 453 represents a bottom view, partly in section, of one of the cylinders, steam chest, and connections used to operate the windlass by steam-power.|
Similar letters of reference, where they occur, denote like parts in all the figures.
The pressure of steam is limited by an automatic pressure-regulating valve, so that if the anchor chain fouls while the engine is running rapidly, it will stop before breaking it or any other part. The shackle and shackle-links at the ends of each length of chain are fitted to the wild-cats, so that they will engage with the stops or ribs, in the same manner as the other links, without mounting the ribs and slipping. Spring-keys are used to connect the wild-cats with the windlass. These keys are placed into square recesses cut out of both the wild-cats and windlass. These recesses extend through the windlass, so as to admit a bar to back out or remove the keys.
The worm-wheel pinion connecting the engines with the windlass is placed on a vibrating rotary shaft, so as to be drawn out of gear to disconnect the engines from the windlass.
The standards for sustaining the hand-power brake are made of wrought-iron plates at such distance apart as to inclose the worm-wheel pinion, and form a column between decks to resist strains of tension as well as of compression.
A spring-valve is used in connection with an automatic pressure-regulating valve, so as to insure perfect safety, even if the latter should stick while open and be inoperative.
The position of the anchors is indicated by a separate counter connected to each wild-cat, so as to register as well in paying out as in taking in the anchor chain.
The eccentrics are set on the engine-shaft, so as to operate the slide-valve of each steam-chest, and keep the exhaust-port open until the piston has reached the ends of the cylinder to avoid the use of water-cocks, and so that
|they can be started and operated from the different decks by any inexperienced person without requiring, the operator to go to the engine to let out condensed water, the admission of steam being delayed until the engine has passed the centre.In the drawings, A represents the frame that supports the shaft b of the windlass B, and the shaft cpassing through the axis of the guiding-pulleys C. The frame A is securely bolted to the deck by diagonal bolts a and other bolts. Upon the central portion of the shaft b the windlass B is mounted. It has a concave gear-wheel with slightly bevel teeth formed upon its periphery, to engage, when desired, with a worm-wheel, E, mounted upon a shaft, e, that is connected by means of cranks e1and connecting-rods e2 with the piston-rods e3 and pistons of the steam-cylinders F. The shaft bcarries also two wild-cat pulleys, D, loose upon said shaft and free to revolve, except when connected with the windlass B by keys d, introduced into openings d‘, formed partly into the flange of the windlass and partly in the rim of each wild-cat. The openings d‘ extend through to the opposite side. The opening there may be made partly circular, and too small to receive one of the keys d, but large enough to receive a crow-bar or hand-spike, f, with which the keys d can be pushed out of the opening d‘ from the opposite side from which they have been introduced, and either of the wild-cat pulleys rendered free to revolve independent of the windlass, upon each side of which the opening d‘ may be made alternately rectangular and semicircular. The keys d are provided with springs, so that they cannot drop accidentally out of the openings d‘, but must be forcibly pulled or pushed out. Each wild-cat pulley is formed with a groove, D1, to receive a brake-band, D2, that is connected with a brake-lever, D3, placed on the side of the frame to save room, and remains connected with said band D2.|
The worm-wheel E and its shaft e are made in one piece and inclined, so as to adapt the mechanism to steam or hand power. For this purpose the shaft e is formed of two lengths, connected by a universal joint, e4. The shaft was formerly supported at its upper end by a key, e5, passing through said shaft, and resting upon washers carried in a cup-bearing, g, as shown in Fig. 449. This bearingg rested upon plates i, attached to, and projecting from, the inside of the wrought-iron standards G, and was moved back and forth by means of the hand-crank H, operating a screw, h, engaging with a nut, g‘, carried by the bearing g. In future the bearing for the upper end of the shaft e is to be fitted as shown in Fig. 454. Steel balls replace the friction plates. The bearing itself is now supported by angle irons, Z (see enlarged view, Fig. 454), upon either side, bent to a radius from the universal joint, thus permitting the screw working
|in the swivel-nut to draw the worm E out of gear. Then the worm-wheel E can be placed in gear with the windlass, and be operated by steam-power, by means of the crank H bringing the worm-wheel E in gear with the windlass B. The windlass is provided with ratchet-gears B’, with which retaining pauls engage, in the usual manner. When the worm-wheel E is thrown out of gear with the windlass through the medium of the handle H, the windlass can be operated by hand by means of the double oscillating brake or lever I (united to ordinary hand-brakes), working upon connecting-rods K, and the latter operating upon levers K’, one end of which clamps the rim of the windlass B. The upper end of each of the connecting-rods K is pivoted to blocks k, that completely embrace the end lever I; and said blocks k can be shifted without any effort, as they are provided with friction-rollers, k‘, and can be clamped upon the lever I in any desired position, to vary the leverage according to the weight that is to be lifted.When operating the windlass by steam, the pressure marked upon the steam-gauge or indicator L will correspond with the strain in tons borne by the anchor-chain, according to the area of the steam-pistons and their relative motion compared with the motion of the chain. Thus the size of the steam-cylinder can be varied so that for each increase of one pound of pressure, as shown upon the gauge, the increase of the strain upon the cable may be one ton, two tons, &c., as may be desired.|
The automatic regulating-valve m is made with a piston loaded to the desired pressure, and connected, to a balance-valve that will, in its upward movement, close, and prevent the further admission of steam to the cylinders F, when the desired pressure is reached. To further insure a safe limit to the strain on the cable, the steam-pipe between the automatic regulating-valve m and the cylinder F is provided with a valve, m‘, loaded to blow off in case the automatic regulating-valve sticks open.
The position of the anchors is indicated by a separate counter connected to each wild-cat, either in paying out or heaving in the cable. Each counter is composed of a star-wheel, n, with preferably ten V-shaped teeth and indentations, with one of which a pin, p, carried by each wild-cat or its hub, engages at each revolution, and a spring, n1, retains the star-wheel immovable, except when advanced or retracted by the pin p. This star-wheel n and a corresponding wheel, n2, upon which ten consecutive numbers are placed, are mounted together upon a short shaft, carrying a worm-wheel, n3, through which the number of revolutions made by the star-wheel are transmitted to an indicator, q, placed upon the frame A, said frame carrying also the star-wheel n and its retaining spring, n1.
Anchor-chains are made in lengths of fifteen fathoms,
|that are united by shackles. These shackles, as now made and connected to the end links of each section of chain, give an increased length between the outer ends of the adjoining links. When so made they are liable to mount the stops and cause the chain to slip, when it only passes over the top of the wild-cat, and does not embrace a large proportion of its circumference. The shackle r is made short, as shown in Fig. 451, to have the distance between the outer ends of the end links s sunited by the shackle, substantially of the same length as any three consecutive links of the chain, so that they will engage the wild-cat in the same manner as other portions of the chain.The slide-valve t of the steam-chest of each cylinder F is operated by an eccentric so set on the engine-shaft that in moving the valve t the exhaust-port is kept open at the end F’ of the cylinder until the piston has reached its extreme position at that end; and the same operation is repeated at the other end. To facilitate the said operation, the slide-valve t may be made with an exhaust-port larger than it is commonly made for effective steam-engines, so as to keep the exhaust-port open until each engine has passed its centre respectively, and allow any water that may be in the cylinder to escape; and even if a small portion of the steam is wasted, this disadvantage is well overbalanced by the convenience of having the engine started and operated from the deck above by any unskilled hand without danger of accidents.|
When it is desired to operate the windlass by steam-power, the worm-wheel E is pushed into gear with the windlass by turning the crank H. Steam is then admitted to the cylinders F from the boiler through the pipe u and cock u1 by means of the hand-wheel u2, or from the deck above with a vertical rod, u3, extending upward from the hand-wheel u2. After steam has been admitted, its pressure is regulated by the valve in, that is loaded to blow off before there is any danger to the cables from too great tension. If steam is not to be used, the worm-wheel is disconnected from the windlass by inclining the shaft e forward with the screw h, revolved by the crank H, and the apparatus is in condition to be operated by the oscillating lever I, attached to the connecting-rods K, and the latter with the clamping-levers K’, that embrace the rim of the windlass B.
It is often desired, when preparing to let go an anchor, to have a few fathoms of chain lying next to the hawse-hole. For this purpose the chain may be passed over either wild-cat by revolving the latter with the hand-spike f, resting upon the horns f‘ as a fulcrum, its extremity passing against the outer ribs of the wild-cat pulley D.
The above description of steam windlass has been recently improved by the addition of a reversing-valve, Fig. 455, Plate 100, which will permit the machine to be
|revolved in either direction, due attention being given to the position of the pauls.In using this windlass, the engine can be started or operated by one person from either deck, without danger of accidents. By extending the main shaft beyond the frame, a small gypsey can be attached, so the power of the windlass may be used for any purpose, as handling the ship at dock.|
This machine has been thoroughly tested, and possesses the advantages of compactness in occupying the smallest possible space, and a design giving great strength with little weight of machine.
It can be readily and efficiently operated by any seaman. The engines can be instantly started without previous preparation.
It is fully protected from undue or dangerous strains by means of its self-acting regulating-valve.
The chain being fitted with the shackles, as shown in Fig. 451, will pass freely over the wild-cats in either direction.