US1423576A - Towing vessels - Google Patents

Description

1,%28,5?6, Patented. July 25, 1922.

3 SHEETS-SHEET1.

T. S. MILLER. Towme VESSELS.

APPLICATION FILED NOV. 10. 1920.

Patented July 25, 1922.

3 SHEETS-SHEET 2.

V M ATTORNEYS T. S. MILLERx TOWING VESSELS.

APPLICATION FILED NOV. 10, 1920.

Patented July 25, 1922.

3 SHEETS-SHEET 3- WINVENTOR.

A TTOR NE Y6 THOMAS SPENCER MILLER, 01 SOUTH ORANGE, NEW JERSEY.-

TOWING vnssnrs' rues, we.

Specification of Letters Patent.

llatenterl July 535, 15-122.

Original application filed. March 22, 1918, Serial No. $323,931. Dividedand this. application filed November 10, 1920'.

To all re/1.0m it may concern Be it known that I. Tiroirixs Firnxonn MILLER, a citizen of the United States, and a resident of South Orange, in the county of Essex and State of New Jersey, have in vented certain new and useful Improvements in Towing Vessels, or which the following is a specification.

My invention relates to new and. useful improvements in towing systems for vessels. In my prior application, Serial No. 177,072, '[iled June 26, 1917, and upon which Letters Patent No. 1,319,601 were granted Oct. 21, 1919, and Serial No. 218,158, tiled February 19, 1918 and upon which Letters Patent No. 1,320,023 were granted October 28, 1919, l have described embodiments of winding engines adapted forthetowing of vessels which are original with me, and in which provision is made to maintain a substantially constant tension in a tow line or hawser, by taking up the line whenever there is a decrease of tension so as to restore the normal tension thereto, or to pay out the line whenever there is a material increase of tension, in order to limit the tension to a desired point. i Vhen I say that the winding engine of my invention maintains a substantially constant tension, 1 do not mean that it maintains an unvariable tension in the towing line, but include within the term small. variations of tension, in contradistinction to the operation oi other known types of towing engines. wherein the stress or tension on the tow line varies as high as 300 or 400 per cent. One of the advantages of such a mode of operation that it enables the use of a towing hawser much lighter, i. e., of less cross section and'also shorter than those commonly employed, even though the towing is to be done in a heavy or rough sea where the wave actionis pronounced. In such a situation,-a winding engine of the type referred'to operates to compensate for either increases or decreases in the tension of the line, so as to maintain an approximately normal tension therein, and thereby relieve the tow line of excessive strain.

My present invention contemplates the application of the same principle to a heavy tow line anchored at its ends to suitable anchoring devices on the towing ship and the towed ship, in order to relieve such a line from strains to which. it may be subjected as the result oi relative movement between Serial No. 422,990.

the ships, due to wave action. In the application of the invention, according to my present invention, the tow line is anchored to the towed vessel and to bollards or other suitable anchoring device or devices on the towing vessel, and. provision is made whereby the anchoring device or devices is relieved oil? the full strain to which they would ordinarily be subjected by the wave action, by so applying the functions of the towing engine to said towing line, that the anchoring device or devices, and the towing line, at the point at which it is connected to said devices, will be relieved of a portion of the strain to which they would ordinarily be subjected, a portion of the strain being sustaiued, or opposed by, the towing engine. In

other words, I provide a system in which the force or strain to which the towing line is subjected, is distributed or divided so that it is in part sustained by the towing engine, and in part sustained by a portion. of the towing line at the point at which it is con nected to the towing vessel. This is an im portant object, because it is well known that when a towing line, which is in normal condition as regards strength throughout its length, is subjected to strains suil'icient to break it, the break occurs at or adjacent to the point at which the towing line is bent about and connected to the anchoring device on the towing vessel.

In my present invention, the towing en gine is provided with a line which iscennected to the towing line at a distance from the point to which said towing line is con nected to one of the vessels, so that the towing engine will be responsive to changes in tension, existing in the major portion of the tow line, due to wave action, and that portion of the tow line between said point of connection, and the anchoring device will be relieved of tension to such an extent as to preclude possibility of rupture of the towing line at the anchoring device, under normal conditions, and while the towing engine functions.

The system or my present invention has the further advantage that, when towing in a smooth sea, under whichconditions the tow line is not subjected to changes in tension due to wave action, the operation of the towing engine may be suspended, and the towing strains sustained wholly by the tow line throughout its length, but should the sea be rough, and the wave action sufficient to warrant it, the towing engine may be placed into action to cooperate with the tow line for the purposes above stated.

My present application is a division of my application Ser. No. 228,931 which was filed in the Patent Ofiice on or about March 22, 1918, upon which application Letters Patent 1,360,968, dated November 30, 1920, was granted and the invention covered thereby consists in the improvements to be more fully described hereinafter, and the novelty of which will be particuarly pointed out and distinctly claimed.

Referring to the drawings by characters of reference, Figure 1 designates a diagrammatic view showing in side elevation a towing vessel and a towed vessel with my pres ent invention applied thereto;

Fig. 2 is an enlarged view in side elevation of the stern portion of a towing vessel showing that end of the towing system which is connected thereto;

Fig. 3 is a View in side elevation of the stern portion of a towing vessel showing my towing system applied thereto, and with the parts in the position assumed when the towing engine is inactive, and the towing is being done by a towing line in the usual well known manner;

Fig. 41 is a view in side elevation of the stern portion of a towing vessel showing a slightly modified form of the invention;

Fig. 5 is a top plan view of a winding engine used in connection with the system shown in Figs. 1 to 41 inclusive, and in itself also constituting my invention;

Fig. 6 is a view in side elevation of the engine shown in Fig. 5;

Fig. 7 is a view in front elevation of the engine shown in Figs. 5 and 6;

Fig. 8 is a sectional View showing the means whereby the engine is controlled to increase and decrease the tension on the towing line, and

*ig. 9 is a plan view of the controlling valve and showing, in dotted lines, the steam ducts.

Referring to the drawings by characters of reference, 1 designates a towing vessel and 2 designates a towed vessel. These ves sels are connected by a towing line or hawser 2, one end of which is connected to the towed vessel, as at 3, and the other end of which is connected to bollards 4;, or suitable anchoring device on the towing vessel.

The towing line or hawser 2 is preferably made in two sections connected by means of eyes 5 and a link 6, so as to provide a flexible hawser section 7 between the bollards 4 and said point of connection, as clearly shown in Figs. 1, 2 and 3. The flexible connection formed by the eyes or links 5 and the link 6 is preferably located adjacent the stern of the towing vessel, so that the section '7 of the tow line will extend in the neighborhood of T5 to 100 feet from the stern of the vessel, although it will be understood that I do not limit myself to this length, as the end section 7 of the towing line or hawser may be of any lengthto give the requisite yield or elasticity when the vessels are subjected to wave action, as will be presently described. Mounted at any suitable point on the hull of the vessel 1, is a winding engine 8 of the type hereinbefore mentioned, that is, one which is capable of regulating the tension in a cable, by paying the same out when the latter is subjected to excessive tension, and to take it up whenits tension falls below normal. This engine may be of the construction heretofore de scribed in my said applications, or may be that shown in Figs. 5 to 8 inclusive.

The drum on this engine is connected by a line 9 to the main line or hawser at a point intermediate the connections between the ends of said hawser and the towing and towed vessel, the point of connection preferably bein at the flexible connection constituted by t e members 5 and 6, heretofore described. I will first describe the construction and operation of the winding engine, and will then describe the operation of the system shown in the Figs. 1 to 4.

Referring to Figs. 5 to 8 inclusive, 10 designatesgenerally the bed frame of a towing engine consisting of the side members 11 connected by transverse members 12, 13. Above these side members 11 are arranged alining bearings 14, in which turns a horizontally disposed transverse power shaft 15 carrying on its outer ends crank discs 16, having crank pins 17. These crank pins 17 are connected by pitmen, indicated in dotand-dash lines at 18, to cross heads 20 sliding on guide-ways 21, and connected to piston rods 22 of pistons (not shown) in fluid pressure engine cylinders 22, mounted on said bed frame, said cylinders being provided with slide valves 23, of any well known suitable type. In view of the fact that the engine cylinders and slide valves may be of any well known structure which will serve the purpose for which they are employed, I do not deem it necessary to illustrate or describe the same specifically herein.

The slide valves are driven from eccentrics 24L mounted on the said powershaft and connected to said slide valves by connecting rods, indicated by dot-and-dash lines at 25. The engine cylinders thus previously described, are employed to operate or control the. power shaft in a manner to be presently described. On the forward. portion of the frame are arranged bearing blocks 26, having arcuate upper bearing surfaces 27, located beneath the power shaft 15, and preferably concentric thereto. Arranged on these bearing blocks 26 to rock or turn on the curved surfaces 27 thereof, are rocking members 28, having curved surfaces 29, preferably curved to conform to the curved surfaces 27 heretofore described. The members 2S constitute the lower members ofa two-part bearing, each of which is completed by an upper bearing part 30 carried by the lower portions of side members 31 of a rocking frame constituted by saidside members and a rear transverse member 32. The bearing members 28, 30 embrace the power shaft 15 which serves in part to support the said frame. The shaft is relieved in part of the weight of the frame and parts, hereinafter described, carried thereby, by the support constituted by the enga ement between the members 28 and the members 26, so that said shaft is relieved from undue strain, and friction between the bearings and the shaft is reduced. On the upper portion of the side members 31, are located alining bearings 33 of any suitable construction, in which turns a drum shaft 3 upon which is mounted a flanged drum 35, and' keyed to said shaft and fixed to the drum 35 is a driving gear 36, which meshes with a driving pinion 37 fixed to the power shaft 15. By the gearing described the drum may, under certain conditions, be held against rotation by the motor, and under other condi; tions, the drum may be driven to take up the towing line. This drum 35 is adapted to receive and have wound thereon, the line 9, heretofore described, the increase in the tension of the line, or decrease therein, serving to rock the drum and drum frame on the shaft 15, and the members 26 as a fulcrum or hearing. This rocking movement is employed to control the action or operation of the engine cylinders to drive the drum to take up the line when the tension of the latter is reduced below normal, or to permit the drum to be overhauled to pay out the line when the tension increases above normal.

The drum frame and the drum are movable on the shaft 15, this movement in the outhauling or pulling direction of the line being opposed by cushioning or yielding means, preferably in the form of coiled springs 38 arranged preferably at the rear of the rocking frame, and exerting their force to swing the frame'in the inhauling direction. The said springs are of such strength as to oppose the forward movement of the drum frame yielding to the pulling stress of the towing hawser, thus permitting said frame to move forward in outhaul direction, and correspondingly shift the hear: ing axis of the drum. Should the tension or pull in the tow line drop, the springs exert their force to move the drum frame and the drum in the opposite or inhauling direction, and swing it together with the bearing axis of the drum in a backward direction. 1 preferably provide two of these springs, the same being of spiral form, and carried by tension or pull bars 39 pivotally connected to the bed frame, as at 40, said pull bars extending upwards from the bed frame, in rear of the swinging drum frame. The springs are confined between a rearwardly extending projection ll on the swing:- iing frame, which projection extends beneath the lower ends of said springs, and by compression plates 42 engagingthe upper ends of the springs, and held in place :by nuts 43 threaded on the upper ends of said bars. By adjusting the nuts 43 lengthwise of the tension bars 39, the compression plates 42 may be adjusted to requlate the expansive force of said springs. From the above description it will be seen that the frame and the drum carried thereby will be movable under changes of tension in the towing line wound on the drum, increases of tension serving to pull said frame forward in the outhaulingr direction, which movement is opposed by the force of springs 38, while decreases of tension in the towing line will result in said springs exerting their force to rock the drum and drum. frame in the inhauling direction. The force of the springs 38 is so regulated as to be under compression, or active under predetermined normal pull on the line so that a material reduction in normal pull or tension will result inthe spring force exceeding said pull, and thereby move the drum and drum shaft in the inhaul direction.

This movement of the drum under changes of tension in the hauling line, is employed to operate a controller, preferably in the form of a controlling valve for the engine, to control the supply of fluid pressure, so that when the tension on the line increas s, the pressure in the cylinders is reduced or relieved to permit the engine to be overhauled or run free until the tension on the towing line is normal, and when the tension on the towing line falls below normal, the supply of fluid pressure is increased, and the engine cylinders operate to drive the drum to wind. in the towing line until the tension of said line is increased to normal.

This result is accomplished in the embodiment shown by the control of a controlling valve for the fluid pressure which will now be described, referring particularly to Figs. 5, 6 and. 8 of the drawings.

44: designates a throttle valve of any suitreversing valve forming part of the controlling valve structure. This controlling valve comprises the vertically disposed casing 49, divided by a vertical partition 50 into cylindrical chamber 51, 52, the latter being connected by oppositely disposed conduits 58 with the valve chests 23 of the engine cylinders 22, one of said conduits being indicated in dotted lines in Figure 8, and both of said conduits being indicated in full lines in Figures 5 and 9. In the chamber 51 is a cylindrical valveway having upper and lower sets of annular openings 54:, 55, and intermediate annular openings 56 com-municating respectively with annular steamways 57, 58 and 59, respectively. The steamway 59 opens to the main steam line supply pipe through the said throttle valve 44, the steamway 57 to the exhaust pipe 60 leading from the cylinder valve chests 23 and the steamway 58 communicates with a port 61 leading to a cylindrical valveway 62 opening at its upper end into the chamber 52 and at its lower end into a port 63 opening through the valveway heretofore described, into the exhaust chamber 64 in the valve casing, the latter also communicating with the exhaust passage 57, as shown in Figure 8. The up per and lower ends of the valve chamber 51 are connected by means of the by-pass or exhaust chamber 64: by means of the ports 65, 66, and the annular passages 67, 68. The main exhaust connection is shown at 69 in Figs. 8 and 9. In the cylindrical valve cage or chamber 51 is arranged a double piston valve having heads 70, 71 connected by a.

reduced portion 72, the said heads being so spaced that when the valve is moved, the space between the heads will span either of the openings 55, 56, or the openings 54:, 56, so that in the first position the exhaust ports 60 of the cylinder valve chests 23 will be connected to the exhaust 69 of the casing, through the chamber 6d, on the one hand, and the steam inlet 48 with the port 61, on the other hand, while in the second position of said. valve, the steam inlet 48 will be con nected to the port 54 to reverse the flow of steam to the en ine c' linders and the vassage will be connected to the exhaust chamber 64; through the passages 66. This piston valve is provided with an extension rod 73 extending through a stuiiing box 74L in the head of the valve casing, such rod being threaded through a hand-wheel nut 75 rotatably mounted on the casing, said hand wheel nut being operable to shift the valve to either of the positions above set forth, and said rod 73 being held against rotation by any suitable means, for eXample, as shown in my said prior applications. In the cylindrical valveway 62 is arranged a cylindrical cage, or liner, 62, having openings 63 communicating with the port 63, openings 61'' communicating with a port 61 and openings 6d communicating with an annular port 65" in the valve casingand surrounding the said line-r. The inlet steam flowing from the inlet port 48 to the port 61 passes through the openings 61 around the head 7 6, out through the ports 64: into the annular port 65* and thence through the conduits 53 leading to the valve chests or the steam engines. Arranged to reciprocate in the cylindrical valveway 62 is a puppet valve consisting of a hollow shell having a head 76 normally located in the chamber 52 and adapted to cooperate with the edge of an annular shoulder 7 6 constituting a valve seat to control the flow of steam between the chamber 52 and the port 61. The head 76 is provided with an annular passage or groove 76 communicating through openings with the bore of the hollow puppet valve, that portion 76 of the head at the, upper end of the latter being formed to engage the inner surface of the upper portion of .the liner 62 and there-b serve as a uide for the reciprocatory movements of the valve. The head is also provided with an opening 76 through which the interior of the valve communicates with the chamber 52. This hollow puppet valve is provided at its lower end with an annular piston head 77 connected to the head 76 by a reduced 3 stem 78 which permits passage of the steam by said valve in passing from port 61, and opening 61 to the chamber 52 and the duct 53 leading to the engine cylinders. The head 77 terminates at its lower end adjacent the passage 68 so that the chamber 52 communicates through the bore of the puppet valve with said passage 63 .under conditions to be described presently. The puppet valve is normally urge-d toward its seatvby an expansion spring 79 seated at one end on said valve, said spring having its opposite end seated in a spring plate 80 in the upper end of the chamber 52, and engaged by an adjusting bolt 81 threaded through the head of the casing, and operable to regulate the expansive force of the spring. Arranged in the valveway 62, beneath the head 77 of the puppet valve, is a piston head 82 which is adapted to engage either the lower end of said head 77 to cut cit communication be tween the chamber 52 and the passage 63 through the puppet valve, or be moved away from said head to permit free communication between said chamber 52 and the passage 63. This piston 82 is carried by a stem 83 having at its lower end an enlarged cylindrical portion 8a slidably disposed in the head 85. The portion 840i the said stem 83 is connected to a vertical threaded rod 86 having a spherical upper end, by a ball and socket joint, as shown in Fig. 8. The rod 86 has a squared or polysided lower end 87 seated in a correspondingly formed seat 88 (see Fig. 6), in the bed-frame 10 to prevent turning of the said stem, but permitting with the pinion 89 on said stem 86, said vertical reciprocation thereof. On this rod 86-is threaded a pinion nut 89 having a collar 90 straddled by a yoke 91, on one end of the lever 92, fulcrumed intermediate its ends, at 93, on the main frame. The end of the lever 92, opposite to that hearing the yoke 91, is connected by a link 98 with a block 9 1-, which is slidab'ly disposed in a slot95 in a bracket 96, rigidly mounted on the lower rear end of the drum frame for movement therewith. ed on an adjusting bolt 97 extending longitudinally of the slot 95 and having bearings 98 in the portions of the bracket at the ends of the slots, said bolt being operable to adjust the block lengthwise of the slot and thereby regulate the degree of throw of the lever under the movements of the drum frame.

By this arrangement it will be seen that whenever the drum frame moves in the out hauling direction, due to an increase of tension in the towing line to overcome the opposing force of the spring 38, the rear portoin of said drum frame will be raised thereby lifting the bracket 96, which results in swinging the lever 92 to lower the yoke 91, the latter movement serving to withdraw the valve head 82 from engagement with the head 77. The sliding adjustable connection consisting of the screw 97, and block 94 affords the proper adjustment of the valve movement. so that it will operate properly when the drum frame moves forward and rearward under changes in tension of the towing line. It will be seen that the block 9 1 may be moved in either direction lengthwise of the slot 95 by means of the screw bolt 97 to thereby vary the swing of the lever 92, and consequently the extent of movement of the piston head 82.

In order to "show the extent of movement of the valve and to give a visible indication that it is functioning properly, I may provide the upper end of the valve 76 with a yoke 100 threaded. into the upper portion of the valve, as at 101, said yoke having connected thereto a rod 102 extending through an opening in the plate 80 and through a longitudinal bore 103 in the bolt 81. as shown in Fig. i. The upper end of the rod 103 may he provided with an indicator or pointer 104 cooperating with a scale 105 to indicate the extent of movement of the valve.

Means is provided for manual ustment, regulation and operation of the puppet valve 76. independently of the automatic means controlled b movement of the drum frame, and is useful for the adiustmentof the valve when setting it for the desired inpullino power. so that the steam pressure will be properly regulated by the automatic control. This means consists preferably in a vertical shaft 106, carrying a pinion 107. in mesh This block is threadpinion 107 being long enough to be in constant driving engagement with the pinion' 89 during all positions of movement or ad justment of the latter lengthwise of the stem 88. On the shaft 106 is a beveled gear 108,

meshing with a'beveled gear 109 on one end of a horizontally disposed connecting shaft 110, said shaft carrying on its opposite end a beveled gear 111 (see Fig. 5) meshing with a beveled gear 112 on the lower end of a vertical shaft 113, mounted in bearings 114 on a valve casing. The shaft 113 carries on its upper end a pinion 115 meshing with a beveled gear 116 on the end of a horizontally disposed shaft 117 mounted in bearings 118, and carrying on one end a hand wheel 119, by which said shaft may be revolved.

The construction and arrangement of the "winding engine and its controlling means being as above described, the operation is as follows: v v

The towing or winding engine is constructed to automatically take in and pay out its line 9, so as to maintain an approximately constant pull thereon, and when arranged to function in this manner, it is set to sustain or oppose either part, or all of the pull on the hawser, according as the dip portion or section 7 is in position tosustain part of the strain, or is depressed to such an extent as to be free of strain, for example, when it is in position shown in Figs. 1, 2 and 1. The normal strain on the hawser or'towing line which is to be sustained or opposed by the towing or winding engine, can be regulated by the operator by means of the manual udjustmeru; heretofore described, within a range of, say from 500 to 25,000 lbs. or more.

If, for example, the towing engine is to be regulated as to exert automatically a pull of 18.000 lbs. on the line 9, and the towing line 9/, at a pressure of 120 lbs. steam pres sure in the engine cylinders, and the valves are in substantially the position shown in 8, when steam is turned. on through the throttle valve 14 the engine will revolve the drum to take up the line 9,. and will continue this winding operation. until the strain on the towing line 9 and the towing line 2 increases toward 18,000 lbs. winding or setting up operation, the movable drum frame carrying the drum, will be held in backward position by the springs 38, that is, in substantially the position shown in full lines in Fig. 8 of the drawings. It

.will be understood that the springs 38 will have an initial force or compression sufficient to hold the drum in this position until sufficient cable stress is applied to the drum and drum frame to tend to pull the drum, and drum frame in the outhawling direction. When the pull on the towing line approaches the determined amount, say 18,000 lbs, said pull will serve to gradually pull the drum 115 Dur ng the 1 this forward movement of the drum frame serving to lift the rear portion thereof, and operating the valve controlling connections to permit the valve head '7 6 to seat on the shoulder 76 for an instant only, and cut off the supply of steam to the engine cylinders, and if such movement is continued, the head or piston 82 will. be withdrawn from the head 77, thereby opening the cylinders to the exhaust 63 through the hollow puppet valve. cylinders 22* will act as a cushion, only to the degree which is required, the exhaust port being instantly closed when the resistance to paying out the towing line is reduced slightly below normal, and valve head 76 is raised slightly to supply the required steam pressure. The point at which the valve 7 6 closes, is determined by he preliminary vertical adjustment of said valve relative to its seat 76 through the operation of the hand wheel 119, shifting the valve stem 86 by means of the nut 90. This operation, i. e., the adjustment of the valve, having taken place, the drum frame normally maintains a position corresponding to the desired pull on the line 9 and the towing line 2, so that increases in the tension in said lines will serve to further pull the drum frame in the outhauling direction against the force of the springs 38, while decreasing in tension will result in the force of said springs being exerted to move the drum frame in the inhauling direction. Should the tension in the line 9 and the towing line 2 be increased, and the drum frame consequently moved in the outhauling direction, the rear end of the drum frame will be raised, lifting the forward end of the lever 92, and lowering the end 91 which is connected to the gear 89, and consequently lowering the stem 86, thereby moving the head 82 away from the adjacent end of the valve head 77 to separate it from the latter, the result being that the chamber 52 will be opened to the exhaust port 63 through the hollow puppet valve 76, and the space provided between the lower end of the latter and the head 82, and the steam will be permitted to escape from the engine cylinders to the exhaust. The

escape of steam from the engine cylinders permits the pull on the line 9 and the towing line 2, to overhaul the engine without increasing the steam pressure in the cylinders until the tension on the towing line 2' and the line 9 drops to the point determined, whereupon, the previously springs 38 will raise the rear end of the frame, and through the valve connection cause the stem 86 and the head 82 to move toward. the puppet valve, until said head 82 engages the adjacent end YT of the puppet valve and closes communication between the The steam pocketed in the engine compressed chamber 52 and exhaust port 63 through the puppet valve, thus maintaining the steam in the cylinders at the required pressure to cushion the pistons and thereby maintain the desired pull on the towingline. By the operation of the hand-wheel 119 in either direction, the connections between the lever 91 and the puppet valve 76 may be changed to regulate the 1 point at which the controlling valve closes, so that the towing engine may be regulated to pull any amount within the limits of capacity of the engine. Should a decrease in tension in the towing line take place, the springs 38 will contract, thereby serving to lower the rear end of the drum frame, and thereby swing the drum frame in the inhauling direction, which will serve to raise the stem 86, and consequently lift the valve 77 from its seat 76, so that the steam inlet through the throttle lcis opened through the port 61 and the valveway 62, to the chamber 52, and the steam is permitted to flow into the engine cylinders to move the pistons therein to drive the drum in a direction to wind the rope thereon, and restore the determine 1 tension in the line 9 and the towing line 2. When the desired tension is reached, the pull on the line moves the drum frame in the outhauling direction, lifting the rear end of said frame against the force of the springs 38, and the valve stem 86 is thereby moved to shift-the head 82 to permit the steam pres sure and the spring 79 to move the valve 76 towards closed position. The description of the operation just given, applies to the operation of the towing line after the same has been connected to the tow, and will be understood that in connecting up the towed vessel to the towing vessel, that the automatic valve does not function. It will also be understood that the above operation applies to conditions wherein thedefleotion or depression of the part 7 of the towing line, is such that said part does not sustain any part, or only an inconsiderable part of the strain on the towing line, under which conditions the tension or pull on the towing line and the line 9 will be the same.

When it is desired to pay out the towing line to connect it to the towed vessel, the hand wheel 119 is operated to set the puppet valve 76 to cause the engines to pull, say 4000 lbs, which raises the said puppet valve from its seat and establishes communication between the chamber 51and port 61. The double headed piston valve 70, 71 is raised to bridge the ports 67, 5S, and thus communication is established between the steam supply and the conduit 62 leading to the cylinders, The flow of steam is thereby reversed from what it is during the towing operation, and the engine may be operated to pay out the towing line under power. it will be understood that during the functioning of the engine yielding and re covering device for the tow line, the reversing valve is in the position shown in Fig. 8 and it is only raised to the position justdescribed when it is desired to drive the engine to positively pay out the line. During the operation as a towing engine, the line is paid out by relieving the pressure in the engine cylinders so that the pull of the line can overhaul the drum and the engine.

Should the distance between the ships increase for any reason, for example, due to wave action, or an increase of speed of the towing ship, and the tension in the towing line 2 is increased above normal, for which the towing engine has been set, the tension on the line 9 will be increased, and the towing engine will pay out said line'in the effort to normalize the tension in its line 9, and in the hawser or towing line 2, and this will continue until the dip or deflection in the hawser section 7 is straightened out sufliciently to assume some of the pulling force exerted on the hawser. As soon as the dip portion 7 of the hawser begins to have tension or pull, there will be less tension or pull on the line 9 to be relieved by the operation of the tension engine, and the tension in the hawser portion 7 increases until finally that share of the pull exerted on the line 9 is reduced to normal, whereupon, the towing engine ceases to pay out the line 9, and holds the line 9 under the previously determined tension, the remainder of the pull on the hawser being sustained by the section 7 of the hawser. The result is, that the major portion of the pull exerted on the towing ship by the hawscr 2, is distributed or d.i-' vided, part being exerted on the towing engine, and part on the device or devices by which the hawser is anchored to the towing ship, and the hawser, at the point at which it is connected to the towing ship, is largely relieved of the strain. For examplgsbduld the tension engine be set to maintain :1 nor mal pull of 18,000 lbs. on its line 0 and on the hawser, under conditions which would maintain the portion 7 of the hawser with little or no strain, there would be 18,000 lbs. pull on the main portion of the hawser, 18,000 lbs. pull on the line 0 sustained by the towing engine, and no pull or strain on the portion 7. Should the relative movement of the ships, from any causes, increase the pull on the main hawser or towing line, say to 24,000 lbs, the effect would be to aighten out the hawser portion i, so that there would be a. substantially continuous trajectory in the hawser between the ships, but the towing engine being set to sustain 18,000 lbs. of the strain, the section 7 would only sustain 6,000 lbs. ofthe strain, which is far beneath any strain necessary or liable to break the hawser. Should the pull in the hawser be then decreased below approximately 24-,000 lbs, the tension in the lines 9 and 7 will be correspondingly decreased, and the towing engine will then act as a recovering device will then operate to take up its line 9 to restore the normal tension therein, which will serve'like ise to pull up the main hawser, thereby restoring the slack in the hawser section 7, whereupon the same tension will be maintained in the line 9 and the towing line 2.

By shutting off the supply of steam to the engine cylinders, by means of the throttle valve 44:, the functions of the towing engines may be suspended, and the hawser composed of the sections 2 and 7 may be employed to serve as a towing connection between the vessels, in which case said sections of the towing line would assume the position substantially as shown in Fig. 8. It will be understood that this arrangement will be found advantageous when towing in smooth seas, or when the wave action or other conditions are such that it is not likely that large changes of tension in the hawser will take place. The towing engine is, however,

all times available to perform the yielding and recovering functions heretofore described, simply by turning on the steam through the throttle valve, and regulating the operation of the controlling valve by means of: a hand-wheel 119.

If desired, one of the crank discs 16 may be provided with a brake band 120 operable by a foot lever 121 to retard the power shaft when the towing line has been paid out, or whenever the functions of a brake are desired.

In towing engines internal friction of the towing engine and its parts has hitherto constituted an important consideration which could not be disregarded, because it, together with the steam pressure, constitute the two forces which oppose the hawser stress, but one of the advantages of my invention is that within reasonable limits this internal friction may be ignored. By way of explanation, suppose a towing machine could be built which would be frictionless and that it would oppose a 30,000 lb. hawser stress at 100 lbs. steam pressure, in which case the only force opposing" the hawser stress would be the force exerted by the steam pressure. In actual practice, however, in an engine of the capabilities mentioned, about 30% (thirty) of the force afforded by the steam pressure would be expended in overcoming the friction in the machine, so that but 21,000 lbs. pull would be available to haul in the hawser. Should the hawser pull exceed 21,000 lbs. it might go as high as the theoretical force exerted by the steam enginei. e., 30,000 lbs, plus the force expended in overcoming friction-i. e., 9000 lbs, which equals 39,000 lbs, that is, the hawser might build up as high as 89,000 lbs. before it would ovehaul the machine and could become slackened, which obviously would result in an extraordinary overstrain in the hawser which might result in the breaking of the latter. These conditions cannot take place in my invention, because the steam pressure is immediately reduced in the cylinders as soon as there is an increase of cable stress above 21,000 lbs. When the hawser pulls beyond 21,000 lbs. the steam is reduced, the hawser is then opposed by the friction of the machine, say 9000 lbs, and a reduced pressure of steam, say about 12,000 lbs. Then if the hawser pull slackens say to 20,000 lbs, the valve opens and the steam pressure is again increased in the cylinders, causing the engine to wind up the hawser until its stress is again raised to normal, whereupon it is held by the engine until there is either an appreciable drop or rise in the hawser stress. The advantage of this is apparent, because I am able to disregard the friction within reasonable limits as the total force of the friction and steam pressure can never exist simultaneously in opposition to the hawser when the hawser stress builds up over the determined normal, inasmuch as the steam pressure is immediately reduced whenever the hawser stress rises above normal and there is consequently no force but the fric tion plus the amount of steam pressure permitted to exist by the opening of the controlling valve in proportion to the degree to which said valve is open. All of the above has assumed that there be no friction in the elements necessary to communicate the movement of the drum frame to the valve. It is clear that themore frictionless these elements are the more nearly uniform can the hawser stress be maintained. However, for practical reasons a slight increase in hawser stress without the engine being overhauled is advantageous because in smooth seas slight raises in hawser stress will not require any movement of the engine. This effects a saving of steam.

For example, a winding-in hawser stress of about 18,000 lbs. and an outhauling hawser stress of about 22,000 would mean that the engine would stand still until the hawser stress exceeds 22,000 lbs, on the one hand, or dropped below 18,000, on the other. The difference in hawser stress in above eX- ample is 1000 lbs. If the difference in hawser stress is much greater than 1000 lbs, then stronger and heavier hawsers must be provided. 1

Under certain conditions itmight be desirable to increase the size of the hawser and regulate the difference between inhauling and paying out much greater than 4000 lbs. perhaps 10,000 lbs. and even more.

In Figure 4 of the drawings isshown a slightly modified form of the invention from that shown in Figures 1 to 3, inclusive, but

in no way departing from the spirit and scope of the invention. In this form of the invention the line 9 instead of being connected directly to the towing line, passes about a block 9 connected to the towing line, from which point said line 9 is doubled on itself as at 9*, and connected to any suitable fixed point 9 on the hull of the vessel. By this arrangement the towing engine can function to sustain or oppose a higher tension in the towing line than is possible by the arrangement shown in Figures 1 to 3. For example, if the towing engine is regulated to sustain or oppose a stress of 18,000 lbs, the arrangement of the line 9 in Figure 4. will serve to utilize this force of 18,000 lbs. on the towing engine to sustain a tension of approximately 36,000 lbs. on the towing line.

In Figure 8, I have shown in dotted lines a modified form of the manual adjustment for the controlling valve. In this form, a gear 122 mounted on a shaft 123 meshes with the gear 89, heretofore described. Said shaft 123 being mounted in a suitable bearing 124 on the valve casing, and in any suitable hearing (not shown) on the bed frame. At the upper end ofthe shaft 123 is a beveled gear 125, meshing with a beveled gear 126 on the end of a horizontal shaft 127, similar to the shaft 117 heretofore described.

While I have illustrated the line 9 connected to a yielding towing engine, it is to be understood that the same results can be attained by other yielding and recovering means supplying the requisite spring action or elasticity, such elastic action being supplied in part or wholly in the connecting line 9 itself, or in mechanism connected with said line.

What I claim and desire to Secure by Letters Patent of the United States is:

1. In combination, a towing vessel and a towed vessel, a hawser connecting said vessels, a line connected to said hawser at an intermediate point, and a yielding and recovering means connected to said line.

2. In combination, atowing vessel and a towed vessel, a hawser connecting said vessels, a line connected to an intermediate point on said hawser, and means on one of said vessels for automatically paying out said line upon a determined increase of tension therein, and for recovering said line upon a determined decrease of tension therein.

3. In combination, a towing vessel, and a towed vessel, a hawser connected to one of said vessels, an extensible connection between the hawser and the other vessel, a line connected to said hawser and to means on said other vessel for maintaining a substantially constant tension in said line.

4.111 combination, a towing vessel and a towed vessel, 2. hawser connected to one of said vessels, a lostmotion connection between the hawser and the other vessel, a line connected to the hawser and to means on said other vessel for maintaining a substantially constant tension in said line.

5. In combination, a towing vessel and a towed vessel, a hawser connecting said vessels, a line connected to the hawser between the vessels, and means on one of said vessels and acting through said line to regulate the tension in said hawser.

6. In combination, a towing vessel and a towed vessel, a hawser connecting said vessels, a fluid pressure device on one of said vessels and sustaining a portion only of the tension on said hawser, the remaining tension being sustained by the connection between said hawser and one of said vessels.

7. In combination, a towing vessel and a towed vessel, a hawser connected to the towed vessel and to a fixed device on the towing vessel, a yielding and recovering means on the towing vessel and connected by a line to an intermediate point on the hawser.

8. In combination, a towing vessel and a towed vessel, a hawser connected to the towed vessel and to an anchoring device on the towing vessel, and means independent of said anchoring device for automatically relieving strain in that part of the hawser connected to said anchoring device.

9. In combination, a towing vessel and a towed vessel, a hawser connected to the towed vessel and to an anchoring device on the towing vessel, and means for automatically relieving strain in that part of the hawser connected to said anchoring device, said means consisting of a line connected to the hawser intermediate its ends, and fluidpressure means on one of the vessels for maintaining a determined tension in said line.

10. In combination, a towing vessel and a towed vessel, a hawser connecting said vessels, a yielding and recovering means on one of the vessels and connected by a line to the hawser at a point intermediate the ends of the latter, and means whereby said yielding and recovering means sustains more of the stress exerted by the hawser than that portion of the hawser connected to said. vessel.

11. In combination, a tOWiIig vessel and a towed vessel, a hawser connecting said vessels, a line connected to the hawser intermediate its ends, means whereby the power of a fluid opposes strain on said line, and means for reducing said power upon increase of strain in said line, and for increasing said power upon a decrease of strain in said line.

12. In combination, a towing vessel and a towed vessel, a hawser connecting said vessels, and a yielding connection between one of said vessels and an intermediate point of said hawser.

13. In combination, a towing vessel and a towed vessel, a hawser connecting one of said vessels to an anchoring device on the other vessel, and means independent of said anchoring device for automatically relieving strain in that part of the hawser connected to said anchoring device.

THOMAS SPENCER MILLER. lVitnesses:

WILLIAM J. PETERSON, THOMAS S. MARTIN.

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