US2929081A - Davits for launching ships' lifeboats - Google Patents

Description

March 22, 1960 H. G: TAYLOR DAVITS FOR LAUNCHING SHIPS LIFEBOATS Filed Dec. 5, 1956 as 24 23 IO United States Patent I 50 2,929,081 DAVITS FOR LAUNCHENG SHIPS LIFEBOATS Humphrey George Taylor, deceased, late of Wolverhampton, England, by Harry R. Powell, Stourbridge, and Thomas H. Wolverson, Wolverhampton, England, administrators, assignors to Welin-Maclachlan Davits Limited, London, England Application December 5, 1956, Serial No. 626,536

Claims priority, application Great Britain December 5, 1955 2 Claims. (Cl. 9-42) This invention relates to davits for launching ships lifeboats, the chief object being to provide new or improved means for steadying the boat whilst the davit is being moved outboard to a position from which the. boat can be lowered away down the ships side.

According to the present invention, the davit is provided or formed with locating abutments which co-operate with the gunwales of the suspended boat so as to steady the latter against lateral swinging on its suspension or falls at all times except when the boat is being lowered away from or hoisted up to the davit.

Preferably the locating abutments on the davit will have associated therewith appropriate leading surfaces which, as the boat being raised approaches the davit, may be engaged by the gunwales so as to steady the boat and guide it into correctly located engagement with said abutments.

Thus the invention provides for the suspended boat being maintained against lateral swinging whilst in the stowed position and throughout the movement of the davit between the stowed and boat-lowering positions.

The invention is more particularly applicable to lifeboat davits of the kind in which the davit arm is guided for rectilinear movement between the stowed and boatlowering positions, for example lifeboat davits of the between-decks type in which the davit arm moves along straight guides fixed to the underside of an upper deck.

An embodiment of the invention, as applied to a lifeboat davit of the between-decks type above mentioned is shown in the accompanying drawing which is a fragmentary sectional view taken athwartships and shows in full outline, the davit arms with the lifeboat suspended therefrom in stowed position between decks, and, in chain lines, the extreme outboard position of the davit arms and lifeboat and also a further position of the latter as it is being lowered away.

Referring to the drawing, each of the two davit arms 10, from the outboard end of which the lifeboat 11 is suspended, is fitted with outer and inner rollers 12, 13 respectively which engage a fixed straight track 14 disposed athwartships between upper and lower decks 15, 16 respectively, and said davit arms are each loaded in the outboard direction by a weight 17 freely suspended by a rope or cable 18 which passes over a system of pulleys 19 and is connected to an anchorage 20 on the davit arm 10 so as to exert an outboard pull thereon to effect, or assist in effecting, the outboard movement of the davit arm 10 when the usual control ropes are payed out by the winch 21. Th track 14 is inclined downwardly in an outboard direction from a position immediately below the upper deck 15, the arrangement being such that, except under abnormal conditions of adverse list, outboard movement of the davit arms 10 will be effected either wholly by the pull exerted by the suspended weights 17 or partly by said pull and partly by the direct gravitational load of the davit arms 10 upon their tracks 14 so long as these have a favourable incli- 2 nation. In the latter event, the proportion in which these two forces act to effect outboard movement of the davit arms 10 will vary with the list; thus with increasing adverse list the proportional effect of the suspended weight 17 will increase and that of the direct gravitational load on the tracks 14 will decrease. In thisconnection, the inclined setting of the tracks 14 and the size of the suspended weights 17 which assist the outboard movement of the davits 10 preferably are such as to ensure that launchings can be carried out successfully under conditions involving up to at least 25 of adverse list.

Each weight 17 works in a normally vertical housing or guideway 22 in the ships side.

The outboard movement of each davit arm 10 is dc termined by its roller 12 engaging the closed outer end of its track 14 which serves as a stop, and each davit arm 10 is of very wide or obtuse V-shape, the limb with the inboard direction from the included angle, and which has the track engaging rollers 12, 13 on it, being aligned with the fixed track 14, whilst-the other limb is either substantiallyhorizontal or, as shown has a small upward inclination toward its outboard end which carries the usual head sheave 23, the pivotally mounted suspension hook or tusk 24 and associated locking device (not shown).

The lifeboat 11 is suspended from the head sheaves 23 on the davit arms 10 by the usual pulley blocks 25 and control ropes or falls 26 which pass inboard over guide pulleys 27 to the winch 21.

In order to steady the lifeboat when in its raised position and also while it is being moved by the davit arms 10 between stowed and lowering positions, the present invention provides a pair of opposed downwardly sloping steadying arms 28' whose inner and upper ends are integrally fixed to the end of the davit arms 10 and whose lower ends are adapted to engage the lifeboat gunwales. As clearly shown in the drawing, the gunwale engaging ends of the arms 28' are provided with locating recesses formed between downwardly presented abutment faces 28 and laterally presented abutment faces 29 which engage between them the boat gunwales 30 to prevent any lateral swinging of the boat when suspended on its falls in either its stowed position or its lowering position except when the boat is actually being lowered away or hoisted up to the davit. To insure during boat hoisting that the gunwales will properly engage the recesses afforded by the faces 28, 29, the arms 28' are provided with inwardly sloping guiding members 31 which as the boat approaches its uppermost position, engage the gunwales and direct them into the recesses.

In the stowed position the load may be partially taken off the suspension hook or tusk by appropriately arranged gripe wires (not shown) connected to suitably positioned anchorages on the upper deck and passed under the lifeboat, said gripe wires including the usual slip hooks for releasing them before launching the boat.

Having fully described the invention, what is claimed and desired to secure by Letters Patent is:

l. A davit for launching ships lifeboats comprising an arm having an outer end containing a head sheavefrom which the lifeboat is suspended, and a pair of opposed downwardly sloping steadying arms having inner ends integrally 'fixed to said davit arm adjacent the-outer end In,..cembination with a davit for launching lifeboats .a lidrof the type having davit arms containing head sheaves from which a lifeboat is suspended and each of which arms is guided for rectilinear movement between stewed and boat lowering positions, a pair of opposed downwardly and outwardly sloping arms having inner ends integrally attached to each of said davit arnis adjacent the ends thereof and having outer ends each provided with a. gunwale receiving recess formed between downwardly and laterally present abutment faces, said recesses being adapted to engage the opposite gunwales of lifeboat to steady the same when the latter is in its f. ra s PO i ion, and guide means integral with (,wil fl y a l nding aby ments for enga i the lifeboat gtmwales as the latter move into fully raised position to direct said gunwales into the recess formed between said downwardly and laterally presented abut ment faces.

References Cited in the file of this patent UNITED STATES PATENTS 669,179 lowers Mar. 5, 1901 1,078,080 AZ Nov. 11, 1913 1 10 E i k n, J y 1, 1,855,013 Dixon et a1. Apr. 19, 1932 1,896,845 Hyland Feb. 7, 1933 2,141,452 Schat Dec. 27, 1938 2,650,378 Weinstein Sept. 1, 1953

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