US2038233A

US2038233A - Boat davit

Info

Publication number: US2038233A
Application number: US665903A
Authority: US
Inventors: Earl G Oppenheim
Original assignee: ROBERT C ROEBLING
Current assignee: ROBERT C ROEBLING
Priority date: 1933-04-13
Filing date: 1933-04-13
Publication date: 1936-04-21
Anticipated expiration: 1953-04-21

Description

prifi 21, 1936. 'E. G. OPPENHEVIM BOAT DAVIT 5 Sheets-Sheet 1 Filed April 1 3,- 1935 all Q l w mvmmmm- I g INVEVNTYOR:

ATTORNEYS April 21, -93 E. G. OPPENHEIM BOAT DAVIT Filed April 15, 1953 5 Sheets-Sheet 2 INVENTOR- BY? @fi a;

ATTORNEYS April 21 1 3 E. a. QPVPENHEIM BOAT DAVIT Filed April 13, 1933 5 Sheets-Sheet 3 INVENTO ATTORNEYS A ril 21, 1936. E. G. OPPEINHEIM Filed April 13, 1933 5 Sheets-Sheet 4 ATTORNEY$ NVENTO BYMS Aprifi 21, 1936. E. e. OPPENHE-IM BOAT DAVIT Filed April 15, 1933 5 Sheets-Sheet 5 ATI'ORN EYS Patented Apr. 21, 1936 UNITED STATES PATENT OFFICE BOAT DAVIT Application April 13, 1933, Serial No. 665,903

19 Claims.

The present invention relates to boat launching and recovering equipment.

A particular object of the invention is to provide such equipment especially, but not exclusively, adapted to lowering lifeboats, such equipment being operable in its normal manner even under extreme conditions of list, in heavy seas, etc.

On passenger liners it is customary to provide lifeboat launching equipment capable of operation even when the ships deck is at an angle of fifteen degrees to the horizontal. equipment is inoperable where the list is appreciably greater than fifteen degrees, for example,

twenty-two degrees or more.

lifeboat launching equipment on the high portion of the deck may and frequently does become inoperable, with the result that only half the lifeboat equipment is available for use in the emer- 0 gency, the useful half being that half along the lower deck edge.

Failure of lifeboat equipment to function under such conditions is recognized. An instance of its recognition is the requirement, for example, that coastwise steamers, engaged principally in transporting freight, must carry twice the number of lifeboats that would be required to take care of the entire crew and all passengers, so that in an emergency, such as one in which a relatively great list occurs, the lifeboats along the lower deck edge will be adequate to take off all persons on board.

In passenger transportation, however, it is impossible to follow this desirable practice, because of the vastly greater number of persons on board. For passenger ships, therefore, it is as much as can be done to provide along both deck edges as many lifeboats as are required. But in any case where the deck lists to such an extent that only half the lifeboats can be lowered, the failure of the other half of such lifeboat launching apparatus renders it useless.

The present invention provides lifeboat launching apparatus capable of launching a lifeboat from both deck edges, and particularly the high deck edge, even where the deck lists to an extreme extent, for example, where the deck is at an angle of as much as thirty-five degrees to the horizontal. 0 A further object of the invention is to provide lifeboat launching equipment of this type in which the boat is carried outboard of its davits and in which the weight of the boat causes its own launching when desired.

Another object of the invention is to provide Much of this,

In such case, the

lifeboat launching equipment including a davit pivoted outboard from its center of gravity, particularly in combination with ropes reeved thereon in such a manner that during the turning of the davit outboard to lower the boat the center of gravity of the boat is automatically lowered a greater distance than the center of gravity of the davit is raised during the first portion of the davit movement.

Another object is to provide a rope reeving for the davits so arranged that the boat is lowered a predetermined distance by the first portion of the outboard turning movement of the davits.

Another object is to provide a novel arrangement of goose-neck davits and cooperating-equipment for lowering the boat normally carried in the re-entrant portion of the davits, the whole construction being such that the boat will not become cradled in its davits in such a manner as to interfere with its launching, but, on the contrary, will, even in a severe list, be readily launchable by its own weight.

Still another object of the invention is to provide cross reeving for automatically trimming the lifeboat being lowered.

Further objects include the provision of novel means for snubbing the lifeboat oscillations that would normally occur in lowering the boat at sea; the provision of means for raising the boat blocks and ropes when the boat has been launched; the provision of novel means for carrying the boat in its davits, and lowering it to the deck edge or loading position, as well as the provision of other means and equipment hereinafter described more in detail and which will become apparent as the following description proceeds.

The accompanying drawings illustrate certain preferred embodiments of the invention, but are not to be taken as definitions of the limits of the invention, reference for that purpose being had to the appended claims.

In the drawings;

Fig. 1 is a fragmentary elevation of one of a pair of davits and cooperating equipment embodying the present invention and showing the normal position of a lifeboat with respect thereto;

Fig. ,2 is a side elevation showing one form of reeving for the lifeboat;

Fig. 3 is a similar view, on a reduced scale, of the same equipment, but showing the lowered lifeboat in the automatically trimmed position it would occupy when the ship is .down at the bow;

Fig. 4 is an enlarged detail view of one of the gripe ropes;

Fig. 5 is a fragmentary horizontal sectional view through a portion of a lifeboat and its cooperating davit;

Fig. 6 is a view in elevation, on a reduced scale. showing in lowered position a lifeboat with a modified form of reeving;

Fig. 7 is a top plan view of a snubber device;

Fig. 8 is an enlarged vertical transverse sectional view taken on the line 8-8 of Fig. 7;

Fig. 9 is a still further enlarged fragmentary view showing the snubber adjustment;

Fig. 10 is a View in side elevation of another form of boat reeving, showing the reeving arrangement itself, but with certain cooperating parts omitted for clarity of illustration;

Fig. 11 is an end view of a portion of one of the lifeboat block releasing devices, and

Fig. 12 is a longitudinal vertical sectional view therethrough taken on the line |2-l2 of Fig. 11.

Referring in detail to the drawings, and particularly to Fig. 1, there is shown the forward davit of a pair of davits forming part of a lifeboat launching apparatus. The other davit of the pair is preferably constructed like the forward davit of Fig. 1. The davit, indicated generally at H, is pivoted at I3 outboard of the ship and below the ships boat deck I5. In accordance with the invention, the davits rock in a vertical plane about their pivots from the housed position of Fig. 1 in a counterclockwise direction, as viewed in this figure, during launching of the lifeboat l1. Each davit has a reentrant upper portion l9, which preferably overlies the ships deck so that the center of gravity of the davit is inboard of the davit pivot I3. It is also preferable that the center of gravity of the assembly of two davits and the lifeboat carried by them in housed position be inboard of the davit pivots, with the result that there is normally no tendency for the assembly to move arcuately outboard.

In accordance with the invention, the lifeboat raising and lowering tackle is so arranged that when the boat is to be launched, the boat may be lowered by its tackle, being directed outwardly by the outboard davit surface as the boat moves downwardly, for example, to the dotted line posion of Fig. 1, in which position the boat is substantially at a level with the ships deck l5 for the purpose. for example, of taking on passengers. During this boat movement, the davits remain stationary. If the ropes of the davit tackle be paid out, the davits will now swing about their pivots arcuately downwardly and outwardly away from the ship. The boat tackle is so constructed and arranged that during the preliminary outboard movement of the davits the distance downwardly travelled by the boat will exceed the distance travelled upwardly by the centers of gravity of the davits. The centers of gravity of the davits during this preliminary davit movement travel arcuately upwardly until they reach the vertical plane passing through both davit pivots, after which they move arcuately downwardly.

The davit tackle may include a single sheave block 2| pivotally carried preferably by the reentrant portion [9 of the davit. The davit control rope 23 may have one end attached to the block 2| and pass around a stationary sheave, thereafter being rove through the block 2| to any suitable form of winding means, such as the drum 25 fixed on a power-driven shaft 21.

This shaft may be mounted in bearings 31 fixed to the ships deck l5.

As shown in Fig. 1, the davit is provided with an upper block 35 and a second block 31 inboard of the first block and preferably extending in an inboard direction from the re-entrant portion IQ of the davit. Near the edge of the ships deck [5, and in any case preferably in an outboard position with respect to the davit block 31, is the winding drum 39 for the rope 4| of the boat tackle. It will be understood that this winding drum may be power-operated from any convenient or suitable source. The drum is shown as having a shaft 43 mounted in bearings 45 fixed to the ships deck l5. It will be understood that the specific means for winding and unwinding this rope and the manner and kind of power supplied may vary in practice. The boat rope M is shown as being attached, preferably by means hereinafter described, to the bow of the lifeboat ll. It passes upwardly in an inboard direction over the sheave of davit block 35, thence through inboard davit block 31 and thence to drum 3!! or other winding means. It will be noted that in raising the boat to the full line position of Fig. 1 it is drawn not only upwardly, but also in an inboard direction. Upon being lowered, the boat rides on the davit surface and is thrust or cammed by the davit surface in an outboard direction. When the boat has been lowered to the dotted line position of Fig. l and the davit is allowed to move outboard, initial outboard movement of inboard davit block 31 tends more and more to shorten the distance and length of boat rope ll between inboard davit block 31 and boat rope winding drum 39. Due to this arrangement of the parts, the downward movement of the boat that occurs as the davit is allowed to move outwardly exceeds upward movement of the davits center of gravity as it moves from its housed position of Fig. 1 to the vertical plane containing the davit pivots. The arcuate outward movement of the davits may be allowed to continue until the lifeboat is in such a position that it can be launched well clear of the ship.

The invention provides means for holding down the inboard side of the lifeboat so that it will not move upwardly with respect to its davits beyond a predetermined point. In the form shown, this means includes a gripe 41 looped at its upper end about a hook 49 formed on or fixed to the inboard boat edge. This gripe has its lower end fixed to the ship and may have its bight positioned by a stay rope 5|. This mechanism aids in insuring that even in case of a severe list of the ship the lifeboat will not be frictionally held or cradled in the re-entrant portions of the davits on the high deck edge to such an extent as to interfere with launching the boat. In launching, the gripe rides off the hook 48.

A gripe 55 may have one end attached to the upper part of the davit, pass around the lifeboat and thence in an inboard direction over a fixed sheave 51 on the davit and thence downwardly to a suitable form of holding device 59. This device may have a holding hook 6| releasable from the gripe 55 by a manually-operated handle lever 63. This arrangement permits instantaneous release of the lifeboat for lowering and at the same time normally maintains it rigidly in housed position against the davits.

It will be understood that boat'tackle is pro-.

vided for the stern of the boat like that above described for the bow of the boat.

The two davits for each boat are preferably connected together by cross-tie devices 65 to insure rigidity of the two-davit structure.

Moreover, a single drum or other winding means may be used for both davits of a pair, and, as indicated in Fig. 2, a single winding means, such as the shaft 43, may be used for the drums of the bow and stern ropes of the lifeboat tackle.

The invention provides means associated with the davit for slidably engaging the lifeboat, and in the form of the invention here illustrated this means is shown as a. track 15 secured to the outboard davit face. Cooperating with the track 15 is a wearing surface, herein shown as a curved plate 11, on the lifeboat. The plate 11 may be secured to a guide strip 19 having an angularly extending edge. This construction is preferably used at both bow and stem of the lifeboat so that the inwardly extending portions of the guides 19, which are located between the two davits, serve as limiting stops against their respective tracks 15 to insure proper positioning of the lifeboat with respect to the davits until the side edges of the boat are clear of the davits.

As shown in Fig. 1, each boat rope II is provided, for attachment to the boat, with a loop, hook, or chain link 8|. In certain modifications of boat reeving herein described, the link 8| is carried by a sheave block. In all cases it may be attached to the boat as shown in Figs. 2, 11 and 12.

Referring particularly to Figs. 2, 11 and 12, a bracket 85 is provided for each end of the boat. Pivoted to each bracket is a hook member 81 having an upper hook portion 89 engaged with the link BI and also having a downwardly extending arm 9|. The hook member 81 is pivoted at 93 to its bracket, and due to the weight of the boat there is a tendency for the hook member to rotate in a clockwise direction, as viewed in Fig. 12, with the result that the hook member normally tends to disengage itself from the link 8|. Such disengagement, however, is prevented by abutment of arm 9| against one arm 95 of a hand lever 91, normally bearing against a plate 98, and pivotally attached at 99 to the upper end of a link IUI, whose lower end is attached toa crank arm I 83 on a shaft I05 rotatably mounted in bearings I 81 fixed within the boat. A release lever I09 is fixed to shaft I95 for the purpose of rocking it in a direction to move the links IIII down.- wardly, thereby moving abutments 95 clear of the hook members 81 to release the boat from its boat tackle. With the construction described, both ends of the boat are simultaneously released, so,

that hand levers 91 would ordinarily not be used, but would be actuated only in some emergency causing the hook members 81 to fail to function, in which event the hand levers may be lifted away from the plates 98 against which they normally bear, to free the hook member from them and thereby permit release of the boat from its tackle.

The invention provides means operable when the boat has been launched, and upon release of the boat from the boat tackle, to raise the links BI and their sheaves, if sheaves are used, as in Figs. 2 and 10, upwardly far enough to clear the heads of persons in the boat.

Fig. 1 shows a preferred means for causing this upward movement, and, as herein shown, there is provided for this purpose a weighted sheave block I I5 not fixed to any part of either davit, but riding on boat rope 4I between its sheave blocks 35 and 31. The weighted sheave block H5 is movably secured to the davit by a rope I I1, whose ends are fixed to the davit and whose bight passes over a secondary pulley I I9 in the weighted sheave block II5.

Upon release of the boat tackle from the boat, the weight of sheave block II5 causes it to move downwardly within the limit allowed by the slack of rope H1, and as it moves downwardly it car'- ries with it its associated run of boat rope 4|, thereby causing the released end of the boat rope to move upwardly.

The invention provides a form of reeving for snubbing boat oscillations that would have a tendency to occur if the ship is pitching while the lifeboat is being lowered from its davits clear of the ship. Figs. 2 and 3 show a form of reeving adapted for this purpose. As here shown, two ropes are used for the boat tackle, the bow of the boat being supported by a bight in one of the ropes and the stern by a bight in the other. In this instance, a rope X has one end wound on drum 39, from which it extends upwardly in an inboard direction to one of the sheaves 31, thence upwardly in an outboard direction to its upper davit block 35. The rope X is rove through this block, thence downwardly to lifeboat block I25, thence upwardly to an inner block 35 on the second davit, thence downwardly in an inboard direction under the sheave of weighted sheave block II5 to inner inboard fixed sheave 31 of the second davit, thence downwardly in an outboard direction to winding drum.

The second boat rope Y is rove similarly, having one end attached to right-hand winding drum, thence extending inboard upwardly to inher inboard sheave block 31, thence upwardly in an outboard direction to inner sheave block 35 of the right-hand davit, thence downwardly to the stern boat-supporting sheave block I25, thence upwardly to outer uppermost sheave block 35 of the left-hand davit, thence inboard downwardly under its weighted sheave block II 5 to; inboard sheave block 31, thence downwardly outboard to winding drum.

Referring to Fig. 3, the boat is here shown in lowered position and the ships deck I5 down by the bow. Where the ship is pitching, the inertia of the boat causes it always to move forward or aft in relation to the davits, the boat-attaching sheave blocks riding forward and aft on their boat ropes during pitching motion of the ship. By hindering the rotation of the boat-attaching sheave blocks, or by increasing friction by a nonrotating substitute for the boat-attaching sheave blocks, the energy transmitted to the boat by the pitching ship is more quickly dissipated, and hence the boat oscillations are materially reduced in number and in violence in comparison with the same energy being dissipated only by nearly frictionless boat-attaching sheave blocks and air friction, for instance.

The total length of rope X between its winding drums is the same as the total length of rope Y between its winding drums, and the boat I 1, due to its own weight, tends to assume a horizontal position. Whether the boat has been lowered much or little, the total length of rope X between its davit head sheaves continues to be the same as the length of rope Y between its davit sheaves, so thatthe tendency of the boat to assume a substantially horizontal position continues whether it is being raised or lowered. In this manner trimming is accomplished automatically.

The invention provides a form of reeving tending to overcome not only the effect of pitching and inwardly from the boat.

motion. Such a form of reeving is shown in Fig. 6. Here the boat is shown in partly lowered position with the davits at their limit of outward movement. Only the davit for the bow of the lifeboat is shown, it being understood that the other davit of the pair has similar tackle. In this construction also a pair of boat ropes are used, one for supporting the bow of the boat and one for supporting the stern, but the ropes of Fig. 6 are rove to minimize sidewise oscillation of the boat due to rolling motion of the ship. In Fig. 6, rope R has an end attached to the forward boat rope winding drum 39 and, in normal or housed position of the davits, passes from the drum inboard upwardly to the inner boat rope block 31 of the davit i i, thence outboard upwardly to outer sheave Ml on the outermost end of the davit, thence downwardly to the bow-supporting block thence upwardly to an intermediate sheave on the second davit, not shown. The intermediate sheave on the second davit is positioned the same as, and corresponds to, the intermediate sheave M3 on the first or forward davit. After passing through the intermediate sheave block MB of the second or rearward davit, the rope R passes over an inner sheave 31 of the second or rearward davit and thence to rearward winding drum 39.

The second rope L is similarly rove with similar tackle and has one end attached to winding drum 39, from which it passes in the direction of the rope R over an inner sheave on the first or forward davit, which davit is shown in Fig. 6, thence to intermediate sheave I43 on the first or forward davit, as shown in Fig. 6 thence downwardly to the stern boat block, not shown, thence upwardly to the outer sheave Ml of the second or rearward davit, thence to an inner sheave 3'! of the second or rearward davit, thence to rearward winding drum 39.

It will thus be seen that the bow of the boat is carried by the bight of rope B, one of whose upwardly extending runs from the boat passes over an outer sheave of one davit and the other of whose upwardly extending runs passes over an intermediate sheave of the second davit. The stern of the boat is carried by the bight of rope one of whose upwardly extending runs passes through the intermediate block of the first davit and the other of whose upwardly extending runs passes over the outer sheave l4! of the second davit. This reeving results in giving a V shape to rope R and a V shape to rope L, when viewed in front elevation. The tendency of the boat to swing inboard and outboard due to rolling of the ship is minimized; for example, any tendency of the boat to move toward the ship, as viewed in Fig. 6, due, for example, to rolling of the ship, would cause the boat-supporting blocks I25 to ride on those runs of ropes R and L extending upwardly The tendency of the boat to move away from the ship would cause the boat-supporting blocks to ride along those runs of ropes R and L extending upwardly and outwardly to the outer sheaves of the davits. Such relative motions oi the boat-supporting blocks on the runs of ropes R. and L are lessened in violence and number of oscillations by introduction of additional friction at the boat-supporting sheaves IE5, or by using a non-rotating substitute for them.

It will be seen that the snubbing and lessening of boat oscillations is accomplished as in the conmotion of the ship, but also the effect of rolling struction described in'connection with Figs. 2 and 3. The tendency of the boat to assume a horizontal position, from bow to stern, is the same as that with the reeving of Figs. 2 and 3.

Referring now to Fig. 10, there is here shown only the rope reeving and necessary sheaves. For clarity of reeving illustration, the davits themselves have been omitted and the boat-supporting sheaves have been omitted. It will be understood, however, that there is a right-hand davit and a left-hand davit, as hereinbefore described, and that the eight sheaves in the righthand group are carried by the right-hand davit and that the eight sheaves in the left-hand group are carried by the left-hand davit; also, that the lifeboat I1 is supported from the ropes, in the manner indicated, by any suitable means, such, for example, as a double sheave block at the righthand or bow and a second double sheave block at the left-hand or stern.

Instead of supporting the boat by double sheaves, the boat ropes of Fig. 10 may support the boat at each end by a frictional pressure-exerting device slidable on the ropes and attached to the boat, such, for example, as the device provided by the present invention, illustrated in Figs. 7, 8 and 9 and hereinafter described.

In Fig. 10 the right-hand davit, understood to be carrying the right-hand sheaves, will be designated as davit I, and the left-hand davit, carrying the left-hand sheaves, as davit II. The same winding means may be employed as the means hereinabove described and including drum means 39 and power-operated drum shaft 43.

Each of the two davits I and II carries near its upper end a pair of outermost sheaves 2t! and 263 and four

innermost sheaves

295, 201, 239 and 2H. These innermost sheaves may be located on the davit in the same position as the sheaves 37, hcreinbefore described. Intermediate the outermost and innermost sheaves, the davit carries a pair of intermediate sheaves H3 and 215. The sheaves 2 l3 and H may be located on the davit in the same position as the sheave M3 in Fig. 6. It is not necessary that the sheaves 2 l3 and 2 I 5, when the davit is in its normal or housed position, be lower than the outermost sheaves 20! and #33, for they may be as high as or higher than the sheaves 2M and 203. The sheaves 213 and H5 are shown, in the reeving diagram of Fig. 10, as beinglower than sheaves Zlll and 203, first, because they may be so located, and second, to indicate that their axes are not in the same vertical plane as the axes of sheaves 201 and 283. With this explanation it will be understood that as an observer views Fig. the sheaves 20! and 293 are nearest the observer; that sheaves 2l3 and THE are inboard thereof, that is, further away from the observer; and that the four

sheaves

295, 201, 209 and 2| 1 are still further inboard, that is, still further away from the observer.

The sheaves carried by the second davit II are similarly arranged. The outermost sheaves carried by davit II are indicated by reference numerals 20 l and 2%; the intermediate sheaves of davit II are indicated by reference numerals M3 and 215'; the innermost sheaves of davit II are indicated by reference numerals 2B5, 25?, 209' and 2H.

In the reeving of Fig. 10, four boat ropes are used and are indicated by reference characters A, B, C and D. The right-hand end of rope A is attached to Winding means 39, from which it runs inboard upwardly over innermost sheave 205, thence outboard upwardly over right-hand outermost sheave 201, thence downwardly to the bow of the lifeboat, thence upwardly toward the second davit II and inboard downwardly over right-hand intermediate sheave 2|5 thereof, thence over innermost sheave 2H andthence outboard downwardly to the winding means.

Boat rope B, starting at the right-hand side of the figure, is attached to the winding means and runs thence upwardly in an inboard direction over innermost sheave 201 of davit I, thence upwardly in an outboard direction over righthand intermediate sheave 213 of davit I, thence to the bow of the lifeboat, crossing boat rope A, thence upwardly toward the second davit and over right-hand outermost sheave 203' thereof, thence inboard downwardly to innermost sheave 209' thereof, and thence outboard downwardly to the winding means.

Boat rope 0, starting at the right, runs from the winding means inboard upwardly over innermost sheave 269 of davit I, thence outboard upwardly over left-hand outermost sheave 203 thereof, thence downwardly to the stern of the lifeboat, thence upwardly to left-hand intermediate sheave 213 of davit II, thence inboard downwardly over innermost sheave 20'! thereof, thence outboard downwardly to the winding means.

Boat rope D, starting at the right, runs inboard upwardly from the winding means over innermost sheave 2| I of davit I, thence outboard upwardly over left-hand intermediate sheave 2| 5 thereof, thence downwardly to the stern of the lifeboat, crossing boat rope C, thence upwardly over left-hand outermost sheave 25! of davit II, thence inboard downwardly over innermost sheave 205 thereof, and thence outboard downwardly to the winding means.

Due to this reeving, each boat rope, if viewed from either the right or left-hand side of Fig. 10, would be observed to run in the direction of a vertical V, being attached either to the bow or stern of the boat at the bottom of the V and at the top of one arm of the V running over an intermediate sheave of one davit and at the top of the other arm of the V running over an outermost sheave of the other davit. Further, all runs of ropes between the outermost sheaves and the innermost sheaves run inboard downwardly; and between intermediate sheaves and innermost sheaves run inboard downwardly; and between all innermost sheaves and the winding means run outboard downwardly. This reeving causes the lifeboat to tend to assume a horizontal position from bow to stern, as with the reeving of Fig. 2, and also tends to decrease side swing in the manner of the reeving of Fig. 6, while retaining all the launching advantages of the reeving of Fig. 1.

It will be noted that all boat ropes are herein shown as having both ends attached to the winding means, though it will be understood that one end of each rope may be fixed and that only its other end need be attached to the winding means.

In the arrangement of Fig. 10 it is assumed that ropes A and B pass under two sheaves having the same axis and in one block, attached to the bow of the lifeboat as hereinbefore described. In such case, the ropes will cross as indicated in Fig. 10. Ropes C and D may pass under similar sheaves in a corresponding block attached to the stern of the lifeboat, in which case ropes C and D will cross as indicated in Fig. 10.

The invention provides means for use instead of sheaves, in connection with all reeving herein described except the reeving of Fig. 1, for sliding frictionally on the boat ropes while at the same time attaching them to either the bow or stern of the lifeboat.

An example of such means, constructed in accordance with this invention, is shown in Figs. 7, 8 and 9, and comprises a plate member 221, L-shaped in cross section and having a plurality of openings 223 therein. A pair of rope-guiding devices 225, which may be composed of inner and outer wire coils, cross each other under the plate ZEI and have their ends projecting upwardly through openings 223 in the plate. A U-bolt 221 receives between its arms the crossed rope guides, and is provided with locking means, such as the nuts 229 and 23l, for clamping it to the plate. This U-bolt also serves to attach the boat ropes to the boat, one being fastened to each of the boat-releasing hooks 89 in the manner indicated in Fig. 12. in place of the loop or link 8| there shown. Above the plate and secured to each upwardly extending end of the rope guides is a U-shaped positioner 239 threaded to receive a machine screw 24I, whose inner end bears against the rope guide 225 and exerts pressure thereon. These positioners, as herein shown, limit movement of the rope guides 225 in the plate 22L and also in cooperation with the machine screw 24l, serve as means for varying the resistance to relative movement between the ropes and rope guides. The desired resistance depends upon the weight to be carried by the boat ropes and should be great enough to prevent too free relative movement, but not great enough to prevent substantial relative movement. For example, the resistance should not be great enough to prevent relative movement where the ship is down by the bow or stern and the lifeboat, in such case, due to its own weight, tends to assume a horizontal position. Nor should the resistance be too great to prevent relative movement between the ropes and the rope guides, tending to stabilize the boat, in cases where the ship is rolling and the lifeboat swings toward and from the ship. It will be evident that, by properly adjusting the pressure of the rope guides on their ropes, too free relative movement will be avoided, but at the same time enough relative movement will be permitted to allow the boat tackle to support the boat at all times in a position tending to stabilization and with a minimum of oscillation.

What is claimed is:

1. A ship having a pair of pivoted davits each having a re-entrant portion, a boat located in their re-entrant portions, each davit having an upper sheave and having a lower sheave inboard of said upper sheave, boat reeving winding means, and boat reeving carrying said boat in said davits and including, for each davit, a line runningfrom said boat to an upper davit sheave, thence to a davit lower sheave and thence downwardly from said lower sheave in an outboard direction directly to said winding means, said winding means including a rotatable member associated with the boat reeving and lying outboard of a plane containing the axis of the davit pivots and containing the axis of at least one of the lower davit sheaves.

2. A ship having a pair of davits each having a re-entrant portion, a boat located in their reentrant portions, each davit having a pivot, the re-entrant portion of each davit lying inboard of its pivot in the normal position of the davit and moving upwardly upon initial outboard movement of the davit, a rotatable member carried by the ship, means for causing a lowering movement of the boat upon initial outboard movement of the davit comprising reeving running from the boat upwardly to the davits, thence inboard of the davits, and immediately thereafter leaving said davits and running downwardly in an outboard direction to said rotatable member, and releasable means for holding said davits inboard with the boat in the davit re-entrant portion.

3. A ship having a pair of davits each having a re-entrant portion, a boat located in their reentrant portions, each davit being pivoted to the ship and movable outboard and downwardly with respect to the ship, the re-entrant portion of each davit lying inboard of its pivot in the normal position of the davit and moving upwardly upon initial outboard davit movement, a rotatable member carried by the ship, means for causing, by initial outboard davit movement, a lowering movement of said boat in excess of the upward movement of the re-entrant davit portions, said means including boat reeving running from said boat upwardly to the davits, thence to an inboard davit portion and immediately thereafter leaving said davits and running downwardly in an outboard direction to said rotatable member, and releasable means for holding said davits inboard with the boat in the davit re-entrant portion.

4. A ship having a pair of davits each having a re-entrant portion, a boat located in their reentrant portions, each davit having a pivot, the center of gravity of each davit lying inboard of its pivot in the normal position of the davit and moving upwardly upon initial outboard movement of the davit, a rotatable member carried by the ship, means for causing a lowering movement of the boat upon initial outboard movement of the davit comprising reeving running from the boat upwardly to the davits, thence inboard of the davits, and immediately thereafter leaving the davits and running downwardly in an outboard direction to said rotatable member, and releasable means for holding said davits inboard with the boat in the davit re-entrant portion.

5. A ship having a pair of davits each having a re-entrant portion, a boat located in their reentrant portions, each davit being pivoted to the ship and movable outboard and downwardly with respect to the ship, the center of gravity of each davit lying inboard of its pivot in the normal position of the davit and moving upwardly upon initial outboard davit movement, a rotatable member carried by the ship, and means for causing, by initial outboard davit movement, a lowering movement of said boat in excess of the upward movement of the centers of gravity of said davits, said means including boat reeving running from said boat upwardly to the davits, thence to an inboard davit portion, and immediately thereafter leaving said davits and running downwardly in an outboard direction to said rotatable member, and releasable means for holding said davits inboard with the boat in the davit re-entrant portion.

6. A ship having boat handling equipment including a pair of davits, a boat carried thereby, and oscillation snubbing means supporting said boat from said davits and including boat reeving running from one of said davits to the other and having a sheave attached to the bow of the boat, and further reeving running from one of said davits to the other and having between the davits a sheave attached to the stern of the boat, said boat having means for simultaneously releasing both of said sheaves therefrom, and said reeving having weight means for raising said sheaves from said boat when they are released therefrom.

'7. A ship having boat handling equipment including a pair of davits, a boat carried thereby, winding means on said ship, and boat trimming tackle supporting said boat from said davits and including outer blocks, inner blocks and intermediate blocks on each davit and a plurality of ropes associated with said blocks, each of said ropes running through an inner block on each davit, an outer block of one of said davits and an intermediate block of the other davit, and, between said last-mentioned two blocks, being associated with said boat, said ropes being associated with said winding means.

8. A ship having boat handling equipment including a pair of davits, a boat carried thereby, winding means on said ship, and boat trimming tackle supporting said boat from said davits and including outer blocks, inner blocks and intermediate blocks on each davit and a plurality of ropes associated with said blocks, each of said ropes running through an inner block on each davit, an outer block of one of said davits and an intermediate block of the other davit, and, between said last-mentioned two blocks, being associated with said boat, and beyond said inner blocks running in an outboard direction to said winding means.

9. A ship having boat handling equipment including a pair of re-entrant davits having their lower ends pivoted to said ship and movable in a Vertical direction about their pivots, a boat carried by said davits in the re-entrant portions thereof, winding means on said ship for raising and lowering said boat with respect to said davits, boat trimming tackle supporting said boat from said davits and including outer blocks, inner blocks and intermediate blocks on each davit, a plurality of ropes associated therewith, each rope running through an inner block of each davit, an outer block of one of said davits and an intermediate block of the other davit, and between said last-mentioned two blocks being associated with said boat, said ropes being associated with said winding means, said davits having raising and lowering tackle and winding means therefor carried by said ship.

10. A ship having boat handling equipment including a pair of davits, a boat carried thereby, winding means on said ship, and boat trimming tackle supporting said boat from said davits and including outer blocks and inner blocks on each davit and a plurality of ropes associated with said blocks, each of said ropes running through an outer block of one of said davits and an inner block of the other and between said blocks having means connected to said boat, detaching mechanism for simultaneously releasing said means from the boat, and elements operable thereupon to raise said means above the boat.

11. A ship having a pair of davits, a boat associated therewith, each davit having a pair of outer sheaves and a pair of inner sheaves, a rope running from one outer sheave of one davit to one inner sheave of the second davit, a second rope running from an inner sheave of the first davit to an outer sheave of the second davit, both of said first-named ropes having sheave means movable thereon and attached to one end of said boat, a third rope running from the other outer sheave of the first davit to the other inner sheave of the second davit, a fourth rope running from the other inner sheave of the first davit to the other outer sheave of the second davit, both of said second-named ropes having sheave means movable thereon and attached to the other end of said boat, and means for moving all of said ropes to vary the position of the boat with respect to said davits.

12. A ship having a pair of davits, a boat associated therewith, each davit having a pair of outer sheaves and a pair of inner sheaves, a rope running from one outer sheave of one davit to one inner sheave of the second davit, a second rope running from an inner sheave of the first davit to an outer sheave of the second davit, both of said first-named ropes having sheave means movable thereon and attached to one end of said boat, a third rope running from the other outer sheave of the first davit to the other inner sheave of the second davit, a fourth rope running from the other inner sheave of the first davit to the other outer sheave of the second davit, both of said second-named ropes having sheave means movable thereon and attached to the other end of said boat, and means for moving all of said ropes to vary the position of the boat with respect to said davits, both of the sheave means having devices for varying frictional resistance to their movement on their respective ropes.

13. A ship having a pair of davits, a boat associated therewith, each davit having a pair of outer sheaves and a pair of inner sheaves, a rope running from one outer sheave Olf one davit to one inner sheave of the second davit, a second rope running from an inner sheave of the first davit to an outer sheave of the second davit, a frictional resistance device slidable on both of said first-named ropes and attached to the bow of said boat, said device having crossed rope guides and pressure exerting elements movable thereon to vary frictional resistance between said guides and their ropes, a third rope running from the other outer sheave of the first davit to the other inner sheave of the second davit, a fourth rope running from the other inher sheave of the first davit to the other outer sheave of the second davit, a frictional resistance device slidable on both of said second-named ropes and attached to the stern of said boat, said device having crossed rope guides and pressure exerting elements movable thereon to vary frictional resistance between said guides and their ropes.

14.. A ship having boat launching equipment including davits, a boat, tackle supporting said boat from said davits and including ropes, and means connecting said ropes to said boat including a frictional resistance device slidable on its rope, said device having a rope guiding sleeve and a. pressure exerting element cooperating therewith and movable against said guiding sleeve to vary the frictional resistance between the guiding sleeve and its rope.

15. A ship having boat launching equipment including davits, a boat, and tackle supporting said boat from said davits and including ropes, and means connecting said ropes to said boat including a frictional resistance device having crossed rope guiding sleeves, each guiding sleeve slidably receiving one of said ropes and guiding one rope across another.

16. A ship having boat launching equipment including davits, a boat, and tackle supporting said boat from said davits and including ropes, and means connecting said ropes to said boat including a frictional resistance device having crossed rope guiding sleeves, each guiding sleeve slidably receiving one of said ropes and guiding one rope across another, said frictional resistance device having a pressure exerting element for each rope guiding sleeve, said elements being movable with respect to their guiding sleeves to vary the frictional resistance between the guiding sleeves and their ropes.

17. A ship having boat handling equipment including a pair of pivoted davits each having a re-entrant portion, a boat located in their reentrant portions, each davit having an upper sheave and a lower sheave inboard of the upper sheave, winding'means positioned outboard of a plane containing two straight lines, one from the pivot of one davit to the lower sheave of that davit and the other from the second davit pivot to the lower sheave of the second davit, boat reeving carrying said boat in said davits and including, for each davit, a line running from said boat to an upper davit sheave, thence to a lower davit sheave, and immediately thereafter downwardly from said lower sheave in an outboard direction to said winding means.

18. A ship having a pair of davits, each having a pair of spaced standing blocks, pivots for the davits, boat reeving passing over the standing blocks of the davits, a boat attached to the reeving, the reeving passing from each end of the boat upwardly to one davit standing block, thence inboard downwardly to the other davit standing block, thence downwardly off the davits to the deck in an outboard direction the continuation of which direction line passes above the pivots, and releasable means for holding the davits inboard.

19. A ship having boat handling equipment including pivoted davits movable into and out of housed position, means for turning said davits outboard comprising a boat for said davits and reeving supporting said boat in said davits, a rotatable member carried by the ship and said reeving running upwardly from said boat to said davits, thence downwardly, and thence leaving said davits running downwardly in an outboard direction to the rotatable member carried by the ship, and releasable means for retaining the boat and davits in housed position.

EARL G. OPPENHEIM.