US1237085A - Boat raising and lowering mechanism. - Google Patents

Description

w. T. OLIVER. BOAT RAISING AND LOWER ING MECHANISM- APPLICATION FILED AUG.3| I916 Patented Aug. 14

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w. T. OLIVER. BOAT RAISING AND LOWERING MECHANISM.

APPLICATION FILED AUG.8. I9I6Q 1,2 37,085 Patented Aug; 14, 1917.

. 2 SHEETS-SHEET Z- awue m coz WOODIBURY T. OLIVER, OF NEWPORT NEWS, VIRGINIA.

BOAT RAISING AND LOWERING MECHANISM.

Specification of Letters Patent. Patentefl Aug, 191, 1917,

Application filed August 8, 1916. Serial No. 113,789.

To all whom it may concern:

Be it known that I, WOODBURY T. OLIVER, a citizen of the United States, residing at Newport News, in the county of Warwick and State of Virginia, have invented new and useful Improvements in Boat Raising and Lowering Mechanism, of which the following is a specification.

This invention relates to a mechanism for raising and lowering life boats, and its primary object is to provide a raising and lowering apparatus including means, automatically operable upon the manual actuation of a controlling device, whereby the boat will be incidentally released for a lowering action.

A further object of the invention is to provide an apparatus of the character described including a lowering mechanism per 86 automatically thrown into action upon the release of the boat and its movement to a primary position to effect the lowering of the boat and its maintenance in position in line within deck for the embarkation of passengers.

A further object of the invention is to provide an apparatus of the character de scribed which is simple of construction, reliable and efficient in action, and'wherein the lowering movements of the boat are governed and controlled by a reliable and eflicient type of retarding and cushioning devices.

Theinvention consists of the features of construction, combination and arrangement of parts hereinafter fully described and claimed, reference being had to the accompanying drawings in which Figure 1 is a longitudinal sectlon through a deck of a vessel showing in side elevation a boat in connection with my improved raising and lowering mechanism, as the parts appear in normal position.

Fig. 2 is a transverse section through a portion of the ship, showing 1n full l nes the normal position of the boat and raising and lowering mechanism, and in dotted llnes certain positions of the boat when released for the lowering action.

Fig. 3 is a side elevation on an enlarged scale of one of the davit frames and arms. and showing the davit arm as fully moved outward.

Fig. 4 is a sectional plan View of the same.

Fig. 5 is a view of the cushloning device shown in Figs. 3' and 4: on an enlarged scale- Fig. v6 is a fragmentary detail view of'the boat and one of its deck supports.

Fig. 7 is a view showing on an enlarged scale the means for locking and releasing the controlling drums of the davit arms.

Fig. 8 is a detail section of one of the davit arms, the brake mechanism, and the associated locking means.

Fig. 9 is a detail section on the line 9-9 of Fig. 8.

Referring to the drawings, 1. designates a life boat which is adapted to be normally supported by chocks or cradles 2 fixed to the deck 3 of the ship, each cradle having a segmental surface 4, extending upwardly and rearwardly from the forward portion 5 thereof on an arc of a desired radius, to support the boat on theinboard side of the keel line, leaving the boat free to move outward when released. The cradles may be 'pr0- vided withrfriction rollers 6 to adapt. the. boat to move into and out of supporting position with a desired ease and freedom.

Fixed to the deck 3 are frame elements? '80 arranged a somewhat greater distance apart than the length of the boat 8 resting in the supports 2, and each of these frame elements is-provided with a slotted guideway 9, the end Walls of which form stops 10 and 11. .85

Pivotally mounted at its lower end, as shown at 12 to the base of each frame element is a davit arm 13, and theupper. or free ends of said arms are provided with the usual outwardly curved terminals 14 .from which the boat is directly supported, as hereinafter described The davit arms normally bear against the stops l0 and are disposed in a vertical position, and are movable outwardly to aninclined position to the. extent. limited by the stops 11, in which position the arms are arranged to permit the lowering or raising of the boat beyond the line of p the side of the vessel, the two positions of the davit arms being. illustrated clearly in full and dotted lines in Fig. 2.

The boat is normally held seated in the 1 concaved seats 4 of the supports 2 by means of fastenings, consisting of lashings of ropes or cables 15, each fastened at one end to the. deck, as shown at 16, and having at its oppo-g site or free end aloop or eye 17, said fasten-f ings being passed about the bow and stern portions of the boat to secure; the same against outward displacement from the sup ports. Fixed to the deck are bifurcated and perforated keeper brackets, 18 adapte to receive the eyes 17 of the fastenings 15, and also to receive locking and releasing rods 19 which engage the eyes and hold the fastenings 15 in position. The adjacent or relatively inner ends of these rods are connected with a pivoted locking and releasing lever 20, above and below the pivotal point thereof, and this lever 20 is provided with a spring actuated dog 21 to interlock with notches 22 and 23 in a locking segment 24, by which the lever may be secured in locking and releasing positions. v

The boat is thus normally held fastened in the supports by lashings 15,but it will be understood that by simply shifting the lever 20 from locking to releasing position the rods 19 will be operated to withdraw them from engagement with the eyes 17 thus disconnectin the ends of the lashings and allowing the boat to swing outward beyond the seat supports'2 and also beyond the line of the adjacent side of the vessel,

as hereinafter described by the force of gravity, an automatic movement of the boat to'a positionready for lowering being thus obtained. In this operation the davit arms 13 swing-in the guideways 9 from contact with the shoulders 10' to contact with the shoulders 11, as will be readily understood. The boat is supported from the-curved ends 14 of the davit arms by suitable tackle comprising cables 25 and 26, each secured at one end with a double pulley block 27 to the coacting davit arm, and thence passing in the form of a loop 28 around said pulley block and a guide sheave or pulley 29 on the adjacent end of, the boat, the construction and arrangement being such as to permit contraction and expansion of the loop in the paying out of the cables to lower the boat and the winding up of the cables to raise the boat back to normal position. The opposite ends of the respective cables pass around guide sheaves 30 on the deck and are secured to drums 31 and 32 on a winding shaft 33, controlled in operation as hereinafter described.

In order to prevent too violent motion of the davit arms in launching the boat, and

also to enable the davit arms to be moved backward to normal position, I provide winding and cushioning devices for cooperation witheach davit arm. Each of these winding devices comprises a winding cable 34 secured at one end to the davit arm, passing intermediately over a guide pulley 35 andsecured and wound at its opposite end around a drum 86 on a shaft 37 to which is also fixed a worm gear 38. Meshing with this 'worm' gear 38 is a worm 39 mounted on a shaft 40 journaled in vertically movable bearings and having an angular end portion 41 for the attachment of a crank or other tool whereby winding motion may be communicated with the drum to retract or move the davit arms back from advance to normal position. The worm shafts are adjustable by means of links 42 to slide the worms into and out of engagement with the worm wheels, and each link is. connected with a crank arm 43 on a rock shaft 44 having another crank arm 45, the crank arms 45 of the respective links being coupled by connecting rods 46 to the locking and releasing rods 19 whereby when said locking and releasing rods are released the connecting rods will be simultaneously drawn.

upon to lower the worms to free'the drum 36 and cable 34 for unwinding motion, while on the contrary when the locking and releasing rods are again moved to locking position the worms will be moved into engagement with the worm wheels, so that the drums may be rotated to wind up the cables for the retraction of the davit arms.

The means for cushioning and controlling the outward movement of the davit arms comprises a lug 47 on each davit arm to.

which is pivoted one end of a piston rod 48, fixed at its opposite end to a piston 49 movable within the cylinder 50 pivoted at its outer and lower end to the davit arm frame, as shownat 51. The cylinder is provided with a by-pass groove 52 of greatest depth at the top of the cylinder and thence gradually diminishing in depth toward the l/Vhen the davits swing cylinder and check and control the outward movements of the davit arms, the groove ducts allowing the fluid to slowly pass by and through the piston from the lower to the upper end of the cylinder, whereby a retarded downward travel of each piston is obtained to prevent slamming and to insure ease ofaction. As each bypass groove allows rapid movement of the oil from the bottom to the top of the cylinder it will be evident that the davit arms will be permitted to freely move outward at the start for a portion of their swing and then to travel more slowly, the pistons passing beyond the shallow ends of the grooves before the arms reach the limit of their movement and thereby trapping a portion of the fluid between the pistons and lower ends of the cylinders for a cushioning action, such oil then escaping slowly through a the ducts in the pistons to allow the arms to 7 is established which gradually becomes re duced by reason of the increasing depth of pin or bolt 57 movable in a keeper 58 similar in construction to the keepers 18. This keeper 58 is adapted to receive the apertured free end of the arm 59 of a bell crank lever 60 to the opposite arm 61 of which is connected a brake band 62 passing arounda brake drum 63 on thedrumv shaft 33, by means of which the brake drum will be normally held locked to hold the winding drums and raising and lowering cables.

from action until the boat has been released and has swung outward by the gravity of its own weight to the dotted line position A shown in Fig. 2 beyond the line of the side of the vessel. Whenthe boat reaches this position the davit arm 13 controlling the latch which has moved to such a position as to cause the retraction of the locking pin or bolt 57, thus releasing the brake lever and permitting the brake band to loosen and release the cable for unwinding movement, so that the boat may descend automatically by gravity to the lowered position shown at A in dotted lines in Fig. 2. Hence when the bolt is released by manual operation of the lever 20 and it swings automatically first to the clear position A through the swinging movements of the davitarms, and then when this position is reached the normally locked winding mechanism will. be unlocked and thus permit the winding cables to have movement so that the boat will automatically descend further to the position A. This position may bring it into alinement with any deck of the vessel, so that while it is held in such position the passengers or crew may embark with safety preliminarily to the lowering of the boat into the water. For the purpose of controlling and cushioning the downward movement of the bolt between positions A and A, I provide a cushioning cylinder 64 and piston 66 connected with a crank 67 on the winding drum shaft, and which piston is provided with oil passages, whereby the unwinding motion of the drums will be governed to let out the cables gently and easily for a gradual and regulated descent of the boat as will be readily understood.

I claim 1. In a boat launching mechanism the combination with a means for normally supporting a boat, gravity actuated davit arms mounted for swinging movement, a

lowering mechanism mounted on the free ends of said" davit arms and adapted to be connected to a boat on said supporting means, manually operated winding means for retracting said davit arms and adapted tobe locked against the'influence of said davit arms, means in operable relation with said davit arms for locking said lowering mechanism when said davit arm is in nor mal posltion, and a manually operated means for simultaneously releasing a boat from said' support and for releasing said wlndlng means.

2. In a boat launching mechanism the combination with a chock for supporting the boat, means for securing a. boat upon said 7 chocks, gravity actuated davlt arms mounted for swinging movement, a lowering mechanism mounted on the free ends of said davit arms'and adapted to engage a boat for lowering the same, automatic-means for controlling the rate of speed at which said lowering mechanism operates, means for controlling the rate of speed at which said davit arms are swung, manually operated means for retracting said davit arms and adapted to be locked against movement under the influence of said davit arms, locking meansfor said lowering means actuated by the movement of said davit arms, and a manually operated means for simultaneously releasing said securing means and said retracting means,

3. In a boat launching mechanism the combination with a frame, a gravity actuated davit arm pivotally mounted in said frame and having a limited movement, a drum rotatably mounted in said frame, a worm gear in driving relation with said drum, a worm adapted to be manually rotated, bearings for said worm movably mounted in said frame whereby said worm may be engaged and disengaged with said worm gear, manually operated means for positioning said bearings, and a cable having its one end aflixed to said davit arm an its other end affixed to said drum.

4. In a boat launching mechanism the combination with means for supporting a boat, manually operated means for releasing a boat on said support, gravity actuated davit arms, lowering mechanism mounted on the free ends of said davit arms and adapted to engage a boat on said supporting means, a drum for each davit and mounted for rotation, worm gears in driving relation with respective drums, worms adapted to be manually rotated, movably mounted bearings for each worm whereby said worms may be engaged and disengaged with their free respective worm gears, means for positioning said bearings, cables having one of their ends affixed to their respective davit arms and having their other ends affixed to their respective drums, and means in operable connection with said which said davit arms swing,

5. In a boatlaunching mechanism, chocks;

for supporting a boat, means for securing a boat upon said chocks, gravity actuated davit arms mounted for swinging movement, lowering mechanism mounted on the free ends of said davit arms and adapted to engage a boat on said chocks, automatic means for controlling the rate of speed at which. said lowering. mechanism operates, means for controllingthe rate of speed at a drum for each davit arm mounted for rotation, worm gears in driving relation with respective drums, worms adapted to be manually r0- tated, movablymounted bearings for each worm whereby said worm may be engaged their respectlve davit arms and having their other ends afliXed to their respective drums, locking means for said lowering means actuated by the movement of said clavit arms, manually operated means for simultaneously releasing a boat on said support and for disengaging said worms from their respective worm gears.

In testimony whereof I afliX my signature in presence of two witnesses.

WOODBURY" T. OLIVER.

Witnesses R. M.'LETT, J A. MASSIE;

Copies ofthispatent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. G.

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