US1828363A - Davit for lifeboats - Google Patents

Description

c. H. FULLER 1,828,363

DAVIT FOR LIFEBOATS 15, 1929 3 Sheets-Sheet 1 Original Filed Jan.

Oct. 20, 1931.

Oct. 20, 1931. c. H. FULLER DAVIT FOR LIFEBOATS 3 Sheets-Sheet 2 Original Filed Jan. 15, 1929 C. H. FULLER Oct. 20, 1931.

DAV '1 FOR [.1 L FEBOATS 15. 1929 3 Sheets-Sheet 5 Original Filed Jnn.

Patented Oct." 20, 1931 UNITED STATES CHARLES H. FULLER, OF PORTLAND, OREGON I DAVI'I FOR LIFEBOATS Application filed January 15, 1929, Serial No. 382,726. Renewed. March 2, 1931.

The main object of this invention is to provide anew form of life boat davit by means of which life boats can be lowered to the water from a deck or raised from the water to the deck with extreme ease,.and requiring only a minimum amount of mechanical skill in the operation thereof. a

The second object is to produce a davit for 1 handling life boats which willnot jack knife or cause its booms to move inboard under a load placed inthe life boat.

The third obje tis to eliminate all of the twisting action from the booms. 7

The fourth object i to provide a pivoted sheave mechanismwhich allows the lines to swing inboard or outboard without the crossing-of the lines. l V.

The fifth object is to eliminate end bracing j of'the masts or booms.

The sixth object is to make it possible to handle the boat and boom arms with one pair of lines, and also that these lines always act in unison. a

These, and other objects, will become more apparent from the specification following as illustrated in theaccompanying drawings, in which:

Figure 1 is a front elevation of the clavit. Figure 2 is a horizontal section taken along the line 22 in Figure 1. Figure 3 is a vertical section taken along the line 3-3 in Figure 1. Figure 4 is a horizontal section taken along the line 4-4; in Figure 1. Figure 5is .I a vertical section taken along the line 55in Figure 1. Figure 6is a section taken along the line66 in Figure 1. Figure? is asection similar to Figure 6 but showing the pawl out of engagement. Figure 8 i is a section taken along the line 8-8 in Figure l. Figure 9 is a fragmentary section throughthe pawl. Figure 10 is a section taken along the line 10-10 in Figure 3. Figure 11 is a section taken along the line 11-11 in Figure 3. Figure 12 is a diagrammatic view of the apparatus showing the brake or the pawl engaged and the life boat being lifted from its support preparatory to launching. Figure 13 is a view similar to Figure 12 but showing the pawl out of engagementand the boat being swung outwardly. Figure 14 is similar to Figure 13 showing the pawl out of engagement and the brake being gradually released to lower the boat to the water. Figure 15 is similar to Figure 14 showing the line rer leased from the boat with the brake or the pawl disengaged and the boat hooks. being raised. Figure 16 is similar to Figure 15 showing the line up and the boom swung inboard to pick up a second boat.

Similar numbers of reference refer to similar parts throughout the several views.

Referring in detail to the drawings, the device consists of three principal parts, namely the stationary masts, the swinging booms l and the operating winch, including the connecting llnes. Y

Masts y Mounted on the deck 20 is a pair of uprightmasts 21, on theupper end of eachof which is a slotted mast head 22' in which is mounted a pair of sheaves 23.; On the outer side of each mast head 22 is mounted a second pair of sheaves 2 1,.the purpose of which will be explained later. tubular in form and slidably' contain' the counterweights 25. Passing through the base 26 of each mast 21 is a horizontal shaft 27 which is rotatable-within the bases 26.

B ooms Secured on the shaft 27 close to the bases 26 are the boom arms 28 each of which has mounted onits swinging end a T-shaped boom head 29. To each boom head 29 is. secured a clamp 30 to which one end-of a line 31'is fastened, the opposite end of the line Themasts 21 are passing between the sheaves 23 and fastening to the counterweight 25; The T-shaped heads 29. are tied together by means of the rods 32 which are joined by a turn buckle 33. Under each side of each boom head 29 is hinged a block3. The sheaves 35of the blocks 3 are hinged on the same axis, which is substantially the axis of a cable passing over the top of both of the sheaves 35. Passing over the sheaves 35 is a boat line 36 one end of which is hooked to the eye 37 of the boat 38. On the line 36 a'short distance above the boat fastening is secured the stop 39, the purpose of which will be explained later.

It is desirable to provide a pair of supports 40 upon which the boat 38 can rest between the masts 21.

Wine/t The shaft 27 extends through a double drum 41 and its elongated hub 42, then through a gear 43 which is secured thereon, after which it journals in the side frame 44 of an operating winch. On one side of the drum 41 is formed a. rolling clutch 45 whose rollers 46 lie within a. brake drum 47, around which is placed a brake band 48 provided with a hand lever 49 which may be latched into an engaged position on the standard 50. The hub 51 of the brake drum 47 is free to rotate on the elongated hub 42, and the hub 51, in turn, is free to rotate in the second winch side frame 52. A gear 53 is keyed on the projecting end of the hub 42. Rotation is supplied to the gear 43 by means of a pinion 54 on the shaft 55, and rotation is supplied to the gear 53 by means of a pinion 56 on the shaft 57. A crank 58 is mounted on the shaft 57 and a crank 59 is mounted on the shaft 55. Between the shafts 55 and 57 is a pawl shaft 60 on which is mounted a pawl 61 provided with a weight 62. The weight 62 is secured directly to the shaft 60; whereas the pawl 61 is secured to the shaft 60 by means of key 63 which lies in a widened keyway 64 in the pawl 61 which provides sufficient freedom of motion for the pawl for the purpose intended.

On the deck 20 are hinged the blocks 65 and 66. To one side 67 of the double drum 41 is secured a. boat line 36 which passes upwardly between the sheaves 24, then through the boom sheaves 35, and is then fastened to the eye 37 in the boat 38.

To the side 68 of the drum 41 is secured a second boat line 36 which passes through the blocks 65 and 66, then around a. sheave 69 on the farther end of the shaft 27, then upwardly between the sheaves 24, then around the sheaves 35 and then down to the boat fastening 37.

The operation of the davit is as follows: If it is desired to launch the life boat 38 the operator engages the pawl 61 with the gear 43 and then raises the boat 38 clear of its supports 40 by rotating the drum 41 through its crank 58. The boat 38 may be moved positively to either side of its center by means of the shaft 27 which swings the arms 28 in unison, under the control of the crank 59. If it is moved outwardly past its vertical center line the weight of the boat will carry it on in the same direction as rapidly as it is permitted to do so, under the 0011- trol of the brake lever 49. The pawl, of course, must be disengaged in order to move the boat laterally. The outward swing of the boat is limited by the counterweights 25, which act as stops within the mast heads 22. When the outward swing of the boom ceases further movement of the boat can only be accomplished by releasing the brake control lever 49, which will permit the boat to descend to the water by merely unwinding the cable from the drum 41. Obviously, a reverse of the movement just described will return the parts to their original position, in which event the stop 39 coming in contact with the boom sheaves 35 causes the boom arms 28 to be moved toward a vertical posi tion.

If it is borne in mind that the function of the gear 43 is to hold the arms 28 in the same relative positions, or to move them in unison from one side to the other of the davits center line, it will be seen that the shaft 27 has very little strain imposed thereon, the actual loads being sustained on the lines 36 and its supporting boom arms 28 and masts .21. It will also be seen that with this arrangement only a very small number of parts are required, and that the operation of launching a boat is reduced to such a simple form that it can be accomplished by the ordinary seaman under the most trying circumstances.

It will also be noted that with this arrangement of parts there is no tendency for the members to jack knife, that is, for the boat to move inwardly under its own load. In fact, the contrary is true, since it moves outwardly under its own load, but must be returned to a central position by the winch.

It will be noted that the sheave center of the mast 21 is approximately midway between the shaft 27 and the sheaves 35, which position is highly important to the successful operation of this davit.

I claim:

1. A life boat davit having a pair of spaced rigid masts, each of said masts having a pair of sheaves mounted at the outer upper end thereof and having a pair of booms hinged between said masts between which a life boat can pass, a boat line at each end of said davit passing upwardly between the sheaves on the outer side of a mast through the boom end and thence downwardly on the inner side of the boom to the boat, and shaftmeans connecting said booms for moving said booms to either side of a vertical position.

2. A life boat davit having a rigid mast having a pair of sheaves at the upper end thereof and a swinging boom, a single line passing between said sheaves and thence through the swinging end of said boom whereby said boom can be maneuvered and a boat can be lowered on either side of the vertical center line of the mast, a winch for operating said line, gearing for moving said boom to either side of its vertical position. means for locking said boom in a fixed position, drum means for spooling said line. a

i i as a stop for limiting the lateral movements brake for said drum, and a ratchet mechanism between said braking drum whereby the unwinding of the line can be retarded by said brake.

3. A life boat davit having a pair of stationary masts, a pair of booms hinged between said masts and adapted to swing past same in inboard or outboard directions, a pair of swinging sheaves on each boom, a boat line passing over said sheaves, one end of each boat line passing downwardly between the booms to a boat fastening and the other end passing downwardly on the outer side of the mast to a winch, a pair of sheaves on the mast head between which said last mentioned line end passes, said mast sheaves being approximately midway between the boom hinge and boom sheaves, a counterbalancing line attached to the swinging end of each boom then passing between a pair of sheaves on said mast adjacent to said first mentioned mast sheaves, and then to a counterweight adapted to serve of the boom.

4. A davit for life boats having a pair of spaced booms between which a life boat can be swung, a mastat the foot of each boom, each mast having a pair of counterweight sheaves mounted at the top thereof approximately midway between the upper and lower ends of said booms, a line secured to the swinging end of each boo-m passing between said counterweight sheaves and having a counterweight secured to the lower end thereof, a winch for operating said davit, a line running through the head of each boom and through the head of its adjacent mast to said winch, tion, and means for moving said booms in unison on either side of a vertical center line passing through the pivotal axis of the boom.

5. In a life boat davit the combination of a winch having a drum for handling two lines in unison, a shaft projecting through both ends of said drum and rotatably mounted with relation to said drum, a pair of spaced masts supporting one of said projecting shaft ends, a gear on the opposite projecting end having operating and holding means thereon whereby said shaft can be rotated independ ently of said drum, a gear on said drum having operating means therefor, a brake drum for retarding the unwinding movement of said drum, a roller clutch between said line and drum brake, a pair of booms secured on said shaft, each of said booms having a pair of sheaves hinged on the upper end thereof, sheaves on the topof said mast, a boom line extending across said boom sheaves having one end passing downwardly through the mast sheaves to a winch and having the other end provided with a boat fastening means, and a stop between said boat fastening means and the nearest boom sheave.

CHARLES H. FULLER.

means for locking said booms in posi-c

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