GB2129742A - Arrangements for putting lifeboats to sea in free fall - Google Patents

Abstract

An arrangement for putting lifeboat (10) to sea in free fall. The arrangement comprises a lifeboat-supporting beam (11), which can be pivoted between substantially horizontal and oblique downwardly extending positions, together with a fastening arrangement with associated lock (20), for securing the lifeboat (10) on the beam (11) during pivoting of the same between said horizontal and said oblique downwardly extending position. The lock (20) is adapted for automatic release of the lifeboat (10) relative to the beam (11) at a definite angular position of the beam, for example after a pivoting of the beam 35 DEG from the starting position. During pivoting of the lifeboat together with the beam the lifeboat can be subjected to an axial movement along the beam for an introductory free fall movement immediately the beam has reached or has passed said angular position. <IMAGE>

Description

SPECIFICATION Arrangements for putting lifeboats to sea in free fall This invention relates to arrangements for putting lifeboats to sea in free fall.

Arrangements exist for putting lifeboats to sea in free fall where the lifeboat can be mounted in a downwardly extending oblique position. However, it is most usual for the lifeboatto be mounted when it occupies a horizontal position and for the lifeboat, thereafter, to be pivoted to a downwardly extending oblique position. In both instances, however, there is required a manual actuation from the inner side of the lifeboat in order to release the lock which secures the lifeboat in the downwardly extending oblique position and, in those instances, problems can be presented in getting the lock released in a simple and easy manner.As a consequence of defects occurring in the lock or actuating means dependent from this or as a consequence of human error in the manual actuation of the locking means, there can occur panic-like conditions due to the absence of momentary release of the lifeboat after the lock has been actuated.

Especially, in an instance where the lock is initially to be actuated after the beam with associated lifeboat is pivoted from a horizontal to a downwardly extending oblique position, problems can be presented in getting the lifeboat released immediately the lifeboat has reached the intended downwardly extending oblique position. In such an instance, one is dependent upon one or a couple of the crew taking care of the release of the lock immediately the lifeboat has been pivoted to the accurately determined, downwardly extending oblique position. The crew must thus - in addition to having to concentrate on the subsequent launching movement with free fall - oversee the pivotal movement of the lifeboat together with the beam in order to be able to release the lock on the lifeboat as soon as possible after said oblique position is reached.This can present considerable problems in practice especially if it concerns untrained crew who are to release the lock.

With the present invention the objective is to be able to ensure a putting out of the lifeboat in free fall in precisely the intended launching position after a pivoting from the horizontal to a downwardly extending oblique position without being dependent upon manual actuation in order to release the lock between lifeboat and beam when said downwardly extending oblique position is reached.

According to the present invention an arrangement for putting lifeboats to sea in free fall comprises a beam for supporting a lifeboat and mounted for pivoting between substantially horizontal and downwardly extending oblique positions and fastening means including a lock device for securing said lifeboat on said beam during pivoting between said positions and adapted for automatic release of said lifeboat relative to said beam at a predetermined angular position of said beam thereby causing said lifeboat to be axially displaced along said beam for an initial free fall movement once said beam reaches or passes said angular position.

In this way, one has thus allowed the movement of the beam itself, in its set path of movement, to determine the precise angular position for release of the lock and setting free the sliding movement of the lifeboat along the beam. This involves the lifeboat immediately the latter together with the beam has reached said determined angular position - being momentarily removed from the action of the lock and thereby being able to effect, immediately, its free fall movement. That is to say, the lifeboat can be put to sea in a continuous movement without unnecessary stopping from the horizontal starting position on the beam, via the predetermined angular position on the beam which, conveniently, can be about 35 from that starting position, with an axial sliding movement along the beam.There is thus the possibility - without being dependent on manual release of the lock between lifeboat and beam - of setting the lifeboat free in a controlled and accurate manner with the momentary release of the lock and the momentary starting up of the free fall movement of the lifeboat.

It is preferred that the lifeboat is provided with a lock component which is located on the lifeboat in order to be subjected to the same pivotal movement as the lifeboat during pivoting of the beam from the horizontal to the downwardly extending oblique position, and that another lock component, which cooperates with the first-mentioned component, is located on the beam, said lock components being provided with a pair of locking surfaces guided or controlled relative to each other, preferably with an elongate curved cam surface on the secondmentioned lock component and a short cam follower surface or a pair of such surfaces on the firstmentioned lock component.

In order that the invention can be more clearly understood, a preferred embodiment thereof will now be described, by way of example, with reference to the accompanying drawings in which: Figure lisa schematic view, in full lines, of a lifeboat in a horizontal, inactive position on an associated horizontally disposed beam and the beam is shown in broken lines in position ready for putting the lifeboat into free fall.

Figure 2 is a side view, in full lines, of the engagement between a lock component located on the beam and a lock component fixed to the lifeboat and, in broken lines, a position is shown for setting the lock components free of each other.

Figure 3 shows the same as shown in Figure 2 seen from above.

Referring to the drawings, there is shown a lifeboat 10 which rests in a horizontal stowed position on a beam 11 on a deck 12 on a ship, a rig or similar craft or permanent installation. The beam 11 consists, in the usually known manner, of two parallel beam members (of which only the one is shown in the drawings for the sake of simplicity), which are arranged one on each side of the lifeboat 10. The beam 11 is pivotably mounted at its one, inner end in a bearing (not shown) fixed to said deck 12, so that the beam 11, with the lifeboat 10 resting on the beam, can be pivoted from the horizontal position shown in full lines to the downwardly extending oblique position shown in broken lines.At 14, there is indicated a stowage lock which locks the beam member of the beam (a lock for each beam member) to an associated fastening on the deck 12 or an associated support memberfastened to the deck. The stowage lock 14 is adapted to be released by manual actuation from the inner side of the lifeboat, immediately the lifeboat is ready for putting out. Thereby the beam 11 with the lifeboat 10 is ready for pivoting from the position shown in full lines to the position shown in broken lines. At 15, there is shown a pressure medium cylinder fixed between a bracket 15a on the deck 12 and the respective beam member of the beam 11.Immediately the stowage lock 14 is released, the weight of beam and lifeboat with contents provides for the necessary pivotal force while the pressure medium cylinder 15 ensures that the beam is pivoted from the horizontal to the downwardly extending oblique position with a pivotal speed adapted for this and with a pivotal angle adapted for this.

To the stern portion 1 0a of the lifeboat 10, there is fastened a fin-shaped lock component 16, which extends obliquely outwards and downwards from the upper portion of the stern portion 10a. The lock component 16 comprises a plate member 16a which, on the upper side, is reinforced with two parallel, verticallydisposed reinforcing plates 16b. In the outer end of the plate member 1 6a, there is cut out a T-shaped cavity 16c, 16d.

To the deck 12, there is welded a rectangular girder 17 which passes across the launching direction of the lifeboat 10. To the inner side of the girder 17, there is secured a sennit 18 with a surrounding fence 19, with a cavity 19a for a lock component 20 which cooperates with the lock component 16 on the lifeboat. The lock component 20 is pivotably mounted at its inner end about a shaft pin 21 which is fastened between two brackets 22 which project laterally outwards from the girder 17.The lock component 20 consists of a vertically disposed plate 20a one end of which supports a sleeve member 20b which is pivotably mounted on the shaft pin 21 in the intermediate space between the brackets 22, and the other end of which supports a transverse, curved cam plate member 29c which extends concentrically about the pivotal axis of the sleeve member20b. In the active position illustrated, the lock component 20 rests against a support piece 23 which is welded to outer ends of the brackets 22 between their oppositely facing inner surfaces 22a. To the plate 20a, there are fixed a pair of handles 20d which project laterally outwards from the plate 20a.An operator who stands on the sennit 18 can, by means of the handle 20d, pivot the lock means 20 from an inactive, stowed away position as illustrated by broken lines in Figure 1 to the active engaged position as illustrated by the full lines in Figure 1. In the active engaged position, after the lifeboat is located in place in the stowed position as illustrated by the full lines in Figure 1, plate 20a of the lock component 20 is received in the stem portion 1 6c of the T-shaped cavity in the lock component 16 while the cam plate member 20c is received in the web portion 16d ofthe T-shaped cavity.

On pivoting the beam 11 from the full line position to the broken line position according to Figure 1,the lifeboat 10 is pivoted correspondinglyfrom the full line position to the broken line position of Figure 2.

In the position illustrated in full lines in Figure 2, there is established a secure engagement between the lifeboat 10 and the deck 12viathe lock compo- nent 20 and the lock component 16. In the position illustrated with broken lines in Figure 2, the lock member 16, as a consequence of the pivoting of the lifeboat 10 together with the beam 11 relative to the lock component 20, is swung so far clear of the lower edge of the lock component 20, that is to say of the cam plate member 20c so that the locking engagement is eliminated and the lifeboat 10 is released for movement in an axial direction along the beam 11.In practice, provision is made for swinging the beam 11 with associated lifeboat at least a couple or some degrees angle past the position which is shown by broken lines in Figure 2 so that the lock component 16 is safely brought out of engagement with the lock component 20 before the pivotal movement of the beam is stopped. It is apparent that, by this, there can be ensured an accurate control and a momentary disengagement of the lock component 16 from the lock component 20, guided by the pivotal movement of the beam 11 and the associated lifeboat 10 based on the weight loading from these together with the braking and cushioning function which is obtained with the pressure medium cylinders 15 of the beam 11.

In the present instance, there is described only the solution in connection with the putting to sea of the lifeboat by a free fall movement. However, it is clear that, in practice, the solution according to the invention can be used together with and as an alternative launching to conventional lowering down of the lifeboat via davit arms or a similar arrangement for putting out (not shown further). On putting out via davit arms, one can first connect fastening hooks (not shown) of the lifeboat to hoisting lines of the davit arms and, thereafter, the beam can be pivoted from the position shown in full lines past the position shown in broken lines to a vertical, downwardly hanging position so that the lifeboat can be put out unhindered by the beam and can be hoisted up again into the starting position and thereafter supported on the beam after this has been swung upwards, via the pressure medium cylinders, to the position illustrated in full lines in Figure 1.

Claims (5)

1. An arrangement for putting lifeboats to sea in free fall which comprises a beam for supporting a lifeboat and mounted for pivoting between substantially horizontal and downwardly extending oblique positions and fastening means including a lock device for securing said lifeboat on said beam during pivoting between said positions and adapted for automatic release of said lifeboat relative to said beam at a predetermined angular position of said beam thereby causing said lifeboat to be axially displaced along said beam for an initial free fall movement once said beam reaches or passes said angular position.

2. An arrangement according to Claim 1, wherein a first component of the lock device is located on the beam for cooperation with a second component of the lock device which is located on the lifeboat, said components being provided with a pair of locking surfaces guided relative to each other.

3. An arrangement according to Claim 2, wherein the first lock device component has an elongate curved cam control surface and the second lock device component has a short cam follower surface our a pair of such surfaces.

4. An arrangement according to Claim 1,2 or 3, wherein the predetermined angular position of the beam is about 35 from the starting position of the latter.

5. Arrangements for putting lifeboats to sea in free fall as ciaimed in Claim 1 and substantially as described herein with particular reference to the accompanying drawings.