US2722906A - Fenders or dummies for use in the protection of vessels and/or docks and harbors - Google Patents

Description

Nov. 8, 1955 A. J. TWEDDELL 2,722,906

FENDERS OR DUMMIES FOR USE IN THE PROTECTION OF VESSELS AND/OR DOCKS AND HARBORS 3 Sheets-Sheet 1 Filed Dec. 15, 1952 Nov- 8. 1955 A. J. TWEDDELL 2,722,906

FENDERS OR DUMMIES FOR USE IN THE PROTECTION OF VESSELS AND/0R DOCKS AND HARBORS Filed Dec. 5 Sheets-Sheet 2 4 WJM v W Nov. 8, 1955 EDDELL Filed Dec. 15, 1952 A, J. w 2,722,906 FENDERS OR DUMMIES FOR USE IN THE PROTECTION OF VESSELS AND/0R DOCKS AND HARBORS 5 Sheets-Sheet I5 7 K fiajwlwh v W atent Ofiice 2,722,906 Patented Nov. 8, 1955 FENDERS 9R DUM'MIES FOR USE IN THE PRO- TECTION F VESSELS AND/GR DUCKS AND HARBORS Archibald John Tweddell, Swaythling, Southampton, England Application December 15, 1952, Serial No. 325,928

Claims priority, application Great Britain November 27, 1952 Claims. (Cl. 114 219) This invention relates to fenders or dummies for use in the protection of vessels and/or docks and harbors.

When a vessel draws alongside any unfendered quay at any time but particularly during adverse weather conditions there is always present the danger of damage resulting, frequently to the vessel and sometimes to the quay also.

Dock authorities and ship owners have in the past used various expedients to mitigate or prevent such damage but unfortunately, and rather remarkably, insomuch as the ship owners do not appear to have realised it, such expedients, while affording excellent protection to the quay, have tended to aggravate the damage suffered by vessels.

The expedients referred to have invariably been in some form of a fender, ranging from the comparatively small and soft cork fender to rope fenders, cane fenders, etc., all usually supplied by the ship owner, to the large solid floating wooden dummy provided by the dock authorities and in general use in some ports.

Fenders supplied by ship owners, whatever the type, are generally suspended from the ships rail and are usually either too small or too hard and solid to afford protection to the ship. Years ago when shell plating and frames were of heavier and more solid construction, these fenders served their purpose, but with modern ships of much lighter construction it is quite possible for an indentation to be made in shell plating by a comparatively soft cork fender, while cane and hard rope fenders are quite capable of punching a hole in the side of a ship.

The solid floating wooden dummy supplied by dock authorities will withstand any shock or pressure, and as it receives the first shock of any impact it affords excellent protection for the quay, but as it absorbs neither shock nor pressure within itself it certainly affords no protection to a vessel; on the contrary it constitutes a very real and constant source of danger to any vessel approaching it.

There are three factors to be considered. First the quay, which is usually solid granite or reinforced concrete; secondly the dummy, which is usually a large solid block of timber, probably 30 ft. x 6 ft. x 4 ft., backed and supported by the quay itself.

The third and most vulnerable factor is the vessel,

which, when being placed alongside the dummy, particularly in adverse weather conditions, may easily be sorbs the shock by collapsing over the whole or part of the area affected, depending upon the severity of the shock of impact. As the dummy is floating in the water with at least four-fifths of its bulk submerged, it will readily be seen that the vessel is exposed to very serious danger of extensive damage at and below her water-line.

Apart from a vessel sustaining damage from the force or shock of a sudden impact in drawing alongside of a quay protected by dummies, particularly in adverse weather conditions, she is constantly exposed to the danger of damage which may be incurred by undue pressure upon the dummies. This may be caused by strong winds, by excessive strain on moorings, or by ranging when lying alongside a tidal quay, and may, and frequently does, result in considerable damage to rivets, shell plating and again possibly frames, all of which can lead to the loss of oil fuel through leaking rivets and thus, to some extent, to the pollution of the adjacent docks or harbor. On the other hand it may lead to sea or dock water leaking into the vessel and thus fouling fresh water tanks and oil fuel tanks or causing damage to cargo, and frequently necessitating extensive repairs before the vessel can sail again, sometimes including the need to drydock, thus causing great inconvenience and loss of revenue to the vessels owners.

The object of this invention is to provide a particular construction of fender which is adapted to float in the water alongside a quay, jetty, dock or harbor wall, or between two vessels which are lying alongside each other, and is so designed that it will be capable of absorbing Within itself great shocks of impact or pressure, thereby preventing or at least mitigating the danger of damage to any vessel engaging with it, while at the same time preventing damage to the quay, jetty, dock or harbor wall.

A fender according to the present invention comprises a number of rigid longitudinal members, each consisting of one or more baulks of timber and being separated one from the other by a number of resilient devices positioned between adjacent longitudinal members, one of which carries a number of transverse rigid slides, on which the other of said longitudinal members can slide, against the action of the resilient devices, when compressive force is externally applied to said fender.

Preferably three longitudinal members are provided, the middle member carrying the transverse slides, the resilient devices, preferably of reinforced rubber, being housed on each side of the middle longitudinal member between the slides carried thereby.

The invention is illustrated diagrammatically in the accompanying drawings in which Figure 1 is a perspective view of the fender with the outer coverings removed and part of the tops of the longitudinal members cut away so as more conveniently to show the internal structure. Figures 2 and 2A show in plan and elevation the front lon- 5 gitudinal member, with the top baulk of timber removed,

Figures 3 and 3A showing similar views of the said top baulk. Figure 4 shows in plan the longitudinal members assembled to form a fender, again with the top, side and end covers removed, and top baulks of each longitudinal member being removed, Figure 5 being a similar view with the top baulks in position and the resilient members also in position. Figure 6 is an end elevation of the arrangement shown in Figure 4, and Figure 7 an end elevation of the arrangement shown in Figure 5. Figure 8 is a detailed sectional view of one of the resilient devices.

Referring to the drawings the fender or dummy comprises a number of rigid longitudinal members, each consisting of one or more baulks of timber, the members being shown respectively in Figure 1 at A, B and C. The member A consists of a length of timber A1 to which are secured by means of bolts or other securing devices, diagrammatically shown at 1, six blocks Aa, Ab, Ac, Ad, A2, A1. The said blocks'are spaced apart so as to form five recesses D. The said longitudinal member is completed by a top baulk of timber A2.

A further longitudinal member C is provided, which is formed similarly to the member A. i As will be seen more particularly from Figure 2, the inwardly projecting faces of the blocks Aa, Ab, Ac, Ad, A2, A are of wedge formation, the purpose of which will be described below. It will, of course, be appreciated that the inwardly directed faces of the members Ca, Cb, Cc, Cd, Ce, C), are similarly shaped.

The fender includes a third longitudinal member indicated generally at B and this comprises a baulk of timber B1 having secured thereto blocks Ba, Bb, Bc, Bd, Be, Bf, as in the case of members A and C. The spaces between adjacent blocks Ba, Bb, Bc, Bd, Be, Bf, are adapted to receive slides in the form of wooden members E. The said slides E (see more particularly Figure 4) are laid transversely with respect to the fender and bridge the spaces between the members A, B and C, the said slides at each end being dovetailed to enter the wedge shaped recesses in the members A and C as is clearly seen from Figure 4.

In the spaces between the slides E on each side of the member B are positioned resilient devices F (see Figure 5); these devices are preferably formed of reinforced rubber rings which may be in the form and shape of a motor vehicle tyre, and filled with cellular or sponge rubber such as F1 (see Figure 8). As will be seen from Figure 8, around the inner perimeter of the resilient devices access holes F2 are provided which allow free entry of air or water when the fender is assembled and in its normal, or fully expanded condition. Complementary with the said resilient devices are solid circular pads or blocks of reinforced rubber F3 which fit within the aperture formed by the circular construction of the said resilient devices. The pads or blocks F3 are freely and readily distortable and have sufiicient resilience to enable them to cause, as will be explained below, the longitudinal members A and C to slide to and fro on the slides B when external pressure is imparted to or released from the fender. If desired, to assist this movement spiral springs may be embedded within the pads or blocks F3.

The fender is completed by cover members of timber which are secured across the top and bottom sides and ends of the members A, B and C. The cover members may be reinforced with metal shoes enclosing the ends thereof. The said cover members are also provided with holes 2 registering with the recesses D in order to allow for controlled escape of Water from the inside of the fender when this is compressed. The cover members also, of course, prevent entry of debris or other undesired matter into the fender, whilst providing for the members constituting the fender to be completely enclosed.

In order to assemble the fender the blocks Aa, Ab, Ac, Ad, Ae, Af, are secured to the baulk of timber A1 and the blocks Ca, Cb, Cc, Cd, Ce, Cf, similarly secured to the baulk C1, the said baulks A1 and C1 being spaced apart sufiiciently to allow of the remainder of the fender to be assembled therebetween. The baulk of timber -B1 to which are secured the blocks Ba, Bb, Bc, Bd, Be, Bf, is then positioned between the baulks A1 and C1 and then the slides E are positioned in the recesses D between the blocks Ba, B b, Bc, Bd, Be, Bf, transversely on the baulks A1, B1, C1. The construction shown in Figure 4has now been assembled.

The resilient devices F are now positioned in the spaces on either side of the member B between the slides E and the top baulks of timber A2, B2, C2 are secured in position so that the fender is formed as shown in Figure 5 and only has to be completed by securing thereto the cover members on the top, bottom, sides and ends. For the sake of clarity these cover members have been omitted, but one of the side covers is shown in elevation in Figure 4. The fender is now completed and for use only has to have secured thereto the necessary means by which it can be suspended from, for example, the side of a ship, or from the dock wall.

When the fender is water-borne, for example, at the side of a dock or the like, the ship is so maneuvered into position, and during this manoeuvring contact will be made between the fenders and the dock wall. A compressive force is therefore imparted to the fender and such force causes the members A and C to slide on the slides E, the blocks Aa, Ab, Ac, Ad, Ae, Af, Ca, Cb, Cc, Cd, Ce, Cf, also sliding against the resilient force of the blocks F in the spaces between the slides E. It will be appreciated that as soon as the compressive force on the fender is released the parts thereof take up their normal position, since the resilient devices assume their original shape thus forcing the remaining parts to their initial or free position.

Additional resilient devices may, if desired, be secured on either or both outer sides of the fender and/or to the top and bottom surfaces thereof to provide protection in the unforeseen event of the fender, when in the water, being turned over upon its side, e. g. in exceptionally heavy weather and particularly when used in places Where there is a big rise and fall of tide.

I claim:

1. A fender for preventing damage to ships and comprising three substantially parallel rigid longitudinal members each composed of a number of baulks of timber, a number of resilient devices positioned between the said longitudinal members so as to separate them one from the other, a number of transverse rigid slides carried by and fixed with respect to the middle longitudinal member, on which slides the other two longitudinal members can slide towards each other and towards said middle member against the action of the resilient devices, when compressive force is externally applied to said fender, and means for limiting movement of said other two longitudinal members away from each other and away from said middle member under the influence of said resilient devices when said compressive force is removed from said fender.

2. A fender for preventing damage to ships and comprising three rigid substantially parallel longitudinal members each composed of a number of baulks of timber, a number of resilient devices positioned between thfl said longitudinal members so as to separate them one from the other, a number of transverse rigid slides carried by the middle longitudinal member, on which slides the othertwo longitudinal members can slide against the action of the resilient devices, when compressive ,force is externally applied to said fender, each of said outer longitudinal members comprising a baulk of timber on which a number of blocks are secured in spaced relationship and a further continuous baulk of timber secured over said blocks, which blocks are formed to interlock with the rigid slides.

3. A freely floating ship protecting fender comprising two outer rigid longitudinal members, each of which is composed of two baulks of timber and a ,number of blocks sandwiched in spaced relation between said baulks; a middle rigid longitudinal member; a number of spaced resilient devices positioned between said middle member and each of said outer members so as tospace said members one from another; and a number of rigid slides carried by said middle member transversely thereto and so positioned as to alternate with said resilient devices along the length of said middle member, said two outer members being slidable towards said middle member on was,

said slides when compressive force is applied externally to said fender, said resilient devices yieldably resisting the sliding of said outer members towards said inner member and tending to restore said outer members to their original position when said compressive-force is removed.

4. A freely floating fender as set forth in claim 3 wherein said blocks and said slides are provided with mating dovetails so as to interlock with each other.

5. A freely floating fender as set forth in claim 3, including cover members for the top, bottom, sides and ends of said fender; said side cover members having drainage holes formed therein.

5 References Cited in the file of this patent UNITED STATES PATENTS

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