US2738913A

US2738913A - Ship's accommodation ladders

Info

Publication number: US2738913A
Application number: US441083A
Authority: US
Inventors: Humphrey G Taylor
Original assignee: Individual
Current assignee: Individual
Priority date: 1954-07-02
Filing date: 1954-07-02
Publication date: 1956-03-20
Anticipated expiration: 1973-03-20

Description

March 20, 1956 FIG.2.

21 I3 IBM H. G. TAYLOR 2,738,913

SHIPS ACCOMMODATION LADDERS Filed July 2, 1954 FIGJ.

\ In uentor By M.64

Attorneys United States PatentO SHIPS ACCOMMODATION LADDERS Humphrey G. Taylor, Lower Penn, near Wolverhampton, England Application July 2, 1954, Serial No. 441,083

3 Claims. (Cl. 228-48) This invention relates to accommodation ladders which are lowered, about a pivotal mounting at one end, to an inclined position alongside the ship and are fitted with a collapsible hand rail structure which requires to be erected when the ladder is in position for use and to be folded down on to or alongside the ladder stringer or side member when the ladder is raised and stowed. Ladders of the kind to which the invention relates are generally operated by davit and winch gear for paying-out and winding in the usual falls, and the inclined fully lowered position of the ladder is determined by a pendant connecting the ladder to an anchorage on the davit, or to a frictionally controlled drum provided for the purpose on the winch, which pendant becomes fully extended and taut to assist in supporting the load and minimise flexing or bending of the ladder when in its inclined position.

With ladders of this kind as hitherto proposed, it has been necessary to erect the hand rail structure by hand once the ladder has been lowered into position for use and this can be a dangerous procedure at sea, since it usually entails the partial descent of the open ladder by a member of the crew.

According to the present invention, in an accommodation ladder of the kind referred to the tautening of the pendant as the ladder approaches the predetermined inclined position is utilised to erect the collapsible hand rail structure. The taut pendant may be utilised to maintain the hand rail structure in the erected position so long as the ladder is in its fully lowered position, and the arrangement is preferably such that as the ladder is raised the pendant slackens and the hand rail structure automatically collapses to a folded down position on to or alongside the ladder stringer. As an additional safeguard, however, locking means may be provided, preferably at the upper or pivoted end of the ladder, for locking the hand rail structure in erected position when the ladder is in use, said locking means requiring to be released before the ladder is raised, so as to allow said hand rail structure to collapse.

An embodiment of the invention will now be described with reference to the accompanying drawings, in which:

Fig. 1 is a side elevation of a ships accommodation ladder in its fully lowered position of use.

Fig. 2 is a side elevation of the same ladder disposed horizontally, as during raising or lowering.

Referring to the drawings, the hand rail structure comprises the hand rail proper and stanchions in the form of parallel links 11 each pivotally connected by their top and bottom end respectively to the hand rail 10 at 12, and to the ladder stringer 13 at 14. Two side rails 15, parallel with the hand rail 10, are also pivotally connected to all the stanchions 11 at 16, and thus the hand rail structure operates as a parallelogram linkage when the stanchions are pivoted about the axes 14.

Referring to Fig. 2, the ladder is shown in a horizontal position supported wholly by falls 17, which falls are paid out and wound in by means of davit and winch gear (not shown) in well-known manner. The falls 17 are conveniently attached to the ladder by eyes 18 which are secured to the axis pins 14 of the two endmost stanchions 11.

The hand rail structure is shown in the collapsed position, which it assumes automatically under the action of gravity by reason of its operating as a parallelogram linkage, the lowermost side rail 15 engaging the upper edge of the ladder stringer 13, so that in efiect the hand rail structure is collapsed downwardly upon the said ladder stringer 13.

The pendant 19, seen in slack condition in Fig. 2, is secured by an eye 20 to the axis pin 14 of one of the stanchions 11, and passes through a hole in a bracket 21 spaced away from the said axis pin 14 along the same stanchion before extending upwardly to an anchorage (not shown) to which its upper end is secured.

Referring also to Fig. 1, which shows the ladder in its fully lowered position of use, it will be seen that books, one of which is seen at 22, at one end of the ladder make pivotal connection with an axis pin 23 provided on the deck platform 24, the deck level being indicated by the chain line-24 The ladder is lowered bodily by means of the falls 17 from the ship deck above that indicated at 24 and in the horizontal position shown in Fig. 2, and whilst still horizontal, the hooks 22 are engaged with the axis pin 23 on the deck platform 24. The right-hand fall 17 in Fig. 1 is then paid out at a faster rate than the other fall, so that the ladder pivots, in clockwise direction in the drawings, about the axis pin 23 until the inclined position of use illustrated in Fig. 1 is approached, whereupon the pendant 19 begins to become taut and to straighten out since it is nearing its fully paid out condition.

The tautening and straightening action of the pendant 19 causes an upward pull to be exerted by the pendant upon the bracket 21 through which the pendant passes, with the result that the stanchion 11 to which said bracket is secured is caused to pivot in anti-clockwise direction from the position shown in Fig. 2 to that shown in Fig. l,

and due to the parallelogram linkage form of the hand rail structure the latter is erected by the pendant 19, and is retained in the erected position shown so long as the said pendant remains taut and the ladder is in its fully lowered position.

As an additional safeguard locking means are provided in the form of a strut 25 which is pivoted by one end on the stanchion 11 nearest the deck platform 24, and has its other end adapted to be engaged with a pin 26 on the hand rail 10, so that the whole hand rail structure is locked in the erected position by the strut 25, which must be released before the structure can collapse. The locking means could be of alternative forms (not shown), for example a similar strut to the strut 25 may be provided to lock together any stanchion 11 with either the ladder stringer 13 or a side rail 15, or any other locking means could be employed which is effective to maintain the parallelogram linkage hand rail structure in its erected position, and requires to be released before the structure can collapse.

It will be noted that in the fully lowered position of the ladder shown in Fig. l, with the pendant 19 fully paid out and taut, the stanchions 11 of the hand rail structure have not been brought up to fully vertical positions but are inclined slightly toward the foot of the ladder. Thus when commencing to raise the ladder by taking up the right hand fall 17, the pendant commences to slacken immediately and the hand rail structure automatically commences its collapsing action under gravity, the bottom side rail 15 engaging the ladder stringer 13 as soon as the pendant is sufliciently slack.

The ladder platform assembly 27, shown in Fig. 1, is erected by hand after the ladder has been lowered into The embodiment described and shown in the drawings could be varied in respect of the method of attaching the pendant 19 so that tautening of it is utilised to erect the collapsible hand rail structure. For example, the pendant may be attached to a lever forming one arm of a bell-crank, the other arm of which is formed by one of the stanchions 11, the arrangement being such that tautehing of the pendant pivots the lever to erect the hand rail structure.

Instead of folding down upon the ladder stringer, the hand rail structure may be arranged to fold down alongside the stringer.

In order to give stability to the ladder when in its operative position, the pendant preferably comprises two suspension ropes or lines connected one to each of the ladder stringers or side members.

Having fully described my invention, what I claim and desire to secure by Letters Patent is:

1. In a ships accommodation ladder having a pivotal mounting at one end and fall means for lowering the ladder about said pivotal mounting into an'inclined position of use, the combination of a collapsible hand rail structure incorporating a hand rail proper, stanchions in the form of parallel links each pivotally connected by one end to the ladder and by the other end to the hand rail proper, a flexible pendant which when taut defines the inclined position of use of the ladder, securing means anchoring said pendant to the ladder at the point of pivotal connection of one of said stanchions therewith, and a bracket on said stanchion having a hole therein through which the pendant passes.

2. In a ships accommodation ladder having a pivotal mounting at one end and fall means for lowering the ladder about said pivotal mounting into an inclined position of use, the combination of a collapsible hand rail structure incorporating a hand rail proper, stanchions in the form of parallel links each pivotally connected by one end to the ladder and by the other end to the hand rail proper, a flexible pendant which when taut defines the inclined position of use of the ladder, securing means anchoring said pendant to the ladder at the point of pivotal connection of one of said stanchions therewith, a bracket on said stanchion having a hole therein through which the pendant passes and whereby the pendant is operative in assuming a taut condition to pivot said stanchion into a vertical position and thereby erect the collapsible hand rail structure, and releasable locking means in the form of a strut for interconnecting the hand rail proper with one of the stanchions so as to lock the collapsible hand rail structure in erected position.

i 3, In a ships accommodation ladder having arpivotal mounting at one end and fall means for lowering the ladder about said pivotal mounting into an inclined position of use, the combination of a collapsible hand rail structure, a flexible pendant connected to said ladder for supporting the same in its inclined position of use, said pendant being substantially vertically tautened by the weight of said ladder, and an operative connection between said pendant and said collapsible hand rail structure-to erect the latter upon the tautening of said pendant by the weight of the ladder.

References Cited in the tile of this patent UNITED STATES PATENTS 296,526 Chase Apr. 8, 1884