US3459151A

US3459151A - Sea anchor

Info

Publication number: US3459151A
Application number: US705085A
Authority: US
Inventors: Takeshi Chiba
Original assignee: Fujikura Parachute Co Ltd
Current assignee: Fujikura Parachute Co Ltd
Priority date: 1967-04-06
Filing date: 1968-02-13
Publication date: 1969-08-05
Anticipated expiration: 1986-08-05

Description

SEA ANCHOR Filed Feb. 13. 1968 7 Sheets-Sheet 1 FIGJ.

VINVENTOR. fA/Q SH/ (H/fi/ ad, M i/4 ATTOR/ViVS Aug. 5, 1969 FIG.2.

Filed Feb. 13. 1968 TAKESHI CHIBA SEA ANCHOR 7 Sheets-Sheet 2 IITTOk/VEKS s- 5, 1969 was. we 3,459,151

SEA ANCHOR Filed Feb. 13. 1968 7 Sheets-Sheet 3 FIG.3.| F!G.4. I

INVENTOR. MK 514/ 14/54 BY v s- 5, 1969 TAKESHI CHIBA 3,459,151

SEA ANCHOR Filed Feb. 13, 1968 7 Sheets Sheet 4 mvsmoa.

x BY Ems/0 (M54 QW @,d%

g- 1969 TAKESHI CHIBA 3,

SEA ANCHOR Filed Feb. 13, 1968 7 Sheets-$heet 5 INVENTOR.

Y 7:4/(55/0 (7175A m ia, 4%; M

J TIJZA/E/S 5, 1969 TAKESHI CHIBA 3,

SEA ANCHOR Filed Feb. 13, 1968 7 Sheets-Sheet 6 FIGJ3.

'FIGJ4.

INVENTOR. MAASH/ (W/BA g- 1969 TAKESHI CHIBA 3,459,151

SEA ancaoa Filed Feb. 13. 1968 7 Sheets-Sheet 7 F! G. I7.

I61: I60 I62 FIGJG.

I N VENTOR.

BY TAKES/W 04 United States Patent Ofice 3,459,151 Patented Aug. 5, 1969 t. Cl. B63!) 21/48 US. Cl. 114-209 8 Claims ABSTRACT F THE DISCLOSURE A sea anchor consisting of a canopy of modified cross shape, suspension lines, a separator of said suspension lines, a center cord, floats and weights on the canopy hem, connectings such as a webbing, shackles and a swivel, and a holding pack, and being characterized in that the sea anchor is easy and reliable in handling, launching, deploying, retrieving and repacking, and that the deployed sea anchor body is kept stably in the optimum deploying state.

The present invention relates to an effective sea anchor. Further, this invention relates to the structures and the deployment system of the sea anchor for fishing vessels observation vessels, etc.

Furthermore, the object of the present invention is to provide a sea anchor which increases the work efliciency of the vessel on the sea, when the wind is rather strong and the waves are rather high, by keeping the bow of the vessel against the wind, preventing the vessel from being washed by side Waves, decreasing the rolling, yawing and inclination of the vessel, and at the same time, decreasing the drift which is brought about by the wind and waves.

Further, the effects and features of the sea anchor of the present invention will be emphasized in the following items:

(1) A drag surface or a canopy which consisting of a flexible and durable material, for example, man-made fiber fabrics such as nylon fabrics and the like, is provided with four notches on the periphery and slot vents at the center to form a modified cross shape when it is developed on a plane surface, and thus a stable sea anchor can be obtained, the drag surface of which is retained in the water without rotation or revolution when it is deployed.

(2) The drag surface is high in the strength/ weight ratio, and further, the drag surface is composed of frameworks of stress member tapes which divide the surface into multiple small parts, and the parts are covered by relatively light membranes which result in easiness to repair because the frameworks check the spread of damaged part of the membrane in the practical use.

(3) The upper portion of the drag surface is provided with small floats and the lower portion of the surface is provided with small weights, and the sea anchor is thus stabilized at the deployment step and after the deployment in the water in cooperation with the shape as described in the paragraph (1).

(4) A center cord is provided between the center of the drag surface and the concurrent point of the suspension lines, in order to promote and ensure the deployment of the drag surface in the water, at the same time, to prevent the drag surface from deflation of deployed shape due to the change of water current, further, to retain always the deploy drag surface at the state of the maximum area in order to obtain the sea anchor of larger effective drag surface.

(5) The sea anchor is provided with a separator of the suspension lines near the concurrent point of the lines in order to prevent the suspension lines from tangling and to eliminate any incomplete deployment of the drag surface, and further to make them easy to be handled on the deck of the vessel.

(6) Necessary number of loop handles are provided on the outer surface of the canopy, each of said loops is fastened with each of auxiliary cord, the other ends of these cords are fastened to a guide ring together. By means of pulling the above-mentioned loop handles or this guide ring by hand, the suspension lines and the center cord are ready to be lined up, and the alignment of the drag surface and the suspension lines can be carried out easily, rapidly and securely.

(7) The sea anchor which consists of a drag surface, suspension lines, a separator, a center cord, etc., as abovementioned, may be folded into a specially designed pack, and the sea anchor can be launched safely, easily and securely into the water even in poor visibility conditions such as in a dark night, in a dense fog, in a downpour, and in a storm, needless to say in strong wind and waves. The sea anchor of the present invention can be expected to deploy in the water in proper order and securely by means of the deployment system of the present invention.

The various features and advantages of the present invention may be more fully understood from the drawings and the following descriptions thereof.

In the drawings:

FIG. 1 is an illustration of a general arrangement in the practical use of the sea anchor of the present invention;

FIG. 2 is a perspective view of the main body of the sea anchor including a drag surface;

FIG. 3 and FIG. 4 are plan views of two examples of the drag surfaces which are developed on a plane surface;

FIG. 5 is a longitudinal sectional view of the drag surface of the sea anchor of the present invention which is provided with a center cord;

FIG. 6 is also a longitudinal sectional view of a drag surface which is not provided with a center cord in order to make a comparison with FIG. 5;

FIG. 7 is a front view of the sea anchor viewed from the side of a separator, and showing that the upper portion of the sea anchor is provided with groups of floats and the lower portion of that is provided with groups of weights;

FIG. 8 is an enlarged perspective view of the portion F in FIG. 7 and shows an example of the construction;

FIG. 9 is a schematic illustration of the configuration near the canopy hem of the drag surface of the sea anchor just before the deployment in the water;

FIG. 10 is a detailed structural perspective view of suspension lines, a separator, a center cord and a connecting webbing of the sea anchor;

FIG. 11 is a longitudinal sectional view nearby the separator;

FIG. 12 is a front view of the separator taken from the left side in FIG. 11;

FIG. 13 is an illustration of the sea anchor which is recovered onto a deck of a vessel after it has been employed;

FIG. 14 is an illustration of the sea anchor as shown in FIG. 13, in which the suspension lines of the sea anchor have been aligned;

FIG. 15 is an illustration of the line-up of the main parts of the sea anchor, i.e., the drag surface, the suspension lines, the separator, the connecting webbing, the shackles and the swivel, and showing the state of just before the packing into the pack on the right end of the figure;

FIG. 16 is an illustration of the appearance of the pack into which the drag surface, the suspension lines and the separator are packed, the flaps of the pack are folded on them, and the pack is locked temporarily by the connect ing webbing, and showing the relations between the cords, lines, buoys and weight, the state of which is just before the launching of the sea anchor;

FIG. 17 is a front view of the pack, the flaps of which are closed; and

FIG. 18 is a schematic illustration of the longitudinal section of the pack which is holding the contents thereof.

In the following, the embodiment of the present invention will be explained definitely in accordance with the accompanying drawings:

Referring to FIG. 1, it shows a general arrangement of the sea anchor of the present invention which being used in the water. In the figure, A is the main body of the sea anchor, and the numeral 1 is a drag surface or a canopy which is made of flexible and durable material such as nylon and other man-made fiber fabrics, and it has a sufiicient area to produce a necessary drag force. The numeral 2 is a skirt hem of the canopy 1, and the numerals 3 are notches provided on the skirt of the canopy 1. In the example of the present invention, there are four notches. The numeral 4 denotes suspension lines of the canopy 1 which are provided between the canopy hem 2 and the separator 10, and the number of which may be sufficient to have the canopy 1 remain stably deployed in the water. The lines are made of flexible material such as nylon cord, etc., which is strong enough to transmit the drag of the water on the canopy 1 to the towline 21 of the vessel. Further, groups of the small floats and groups of the small weights are provided at the top portion 2a and the bottom portion 2b of the canopy hem 2, respectively, in order to realize an easy deployment of the canopy and to stabilize the attitude of the canopy in the water, as shown in FIGS. 7 and 8. The numeral 5 is a center cord which is made of the same material as that of the suspension lines 4, and the center cord 5 is provided between the center C of the canopy 1 and the concurrent point B of the suspension lines 4. The numeral is a separator of the suspension lines 4, and is connected with the connecting webbing 6 through the branches 6, 6' of said webbing. The connecting webbing 6 is connected with an end of the towline 21 through the

shackles

7 and 9, and intermediate swivel 8. The other end of the towline 21 is fastened to the bow section of the vessel 23. The numeral 14 denotes slot vents provided at the center portion of the canopy 1, and they reduce the shock load which is brought about onto the canopy 1 by a change of water current. The numeral 11 indicates loops provided at proper positions of the outer surface of the canopy 1 in order to facilitate the alignment of the main body A of the sea anchor as further disclosed in the following: The numeral 12 denotes auxiliary cords which are fastened to the loops 11, and the numeral 13 is a guide ring to which said auxiliary cords 12 are fastened at the other ends thereof. A connecting cord 15 is loosely inserted in said ring 13-. The numeral 16 is a pack which holds the main body A of the sea anchor in the manner as to be expected the complete deployment of the sea anchor. One end of said connecting cord 15- is fastened to the point B at the bottom of the pack 16 and the other end of the cord 15 is fastened to the center C of the canopy 1. The pack 16 becomes inside out after the completion of the deployment of the sea anehor as shown in FIG. 1. Further, one end of the connecting cord 17 is fixed to the point E of the pack 16 and the other end G of the connecting cord is connected with the connecting cord 18 to the buoys 19 and with the connecting cord 18 to the weight 20. The pulling line 22 is a little longer than the towline 21, and one end of which is fastened to the lugs 30 (see FIG. 16) and the other end of the line 22 is fastened to the bow section of the vessel so that it is employed when the sea anchor is recovered from the sea. In the figure, D indicates the wind direction and W indicates the wavy surface of the sea.

FIG. 2 shows the main body of the sea anchor, in which the structure ofthe separator 10 and around the separator is further illustrated in details in FIGS. 10, 11 and 12, inclusive. The numeral 6' denotes the branches of the connecting webbing 6.

FIGS. 3 and 4 are two examples of the structures of the canopy 1 of the sea anchor of the present invention, in which the numerals 1a and 1b are tape stress members, the numeral 2c denotes membranes which are attached to the frame-work of the stress members and form a drag surface, and the

numerals

2a and 2b are top and bottom of the canopy which are provided with groups of the small floats and groups of the small weights, respectively.

FIG. 5 is an illustration of the function of the center cord 5. The longitudinal section of the deployed canopy 1 forms two arcs by the center cord 5 as shown in the figure. The greater part of the water current Sc against the center of the canopy runs toward the outer edge of the canopy 1 passing along the two arcs, and then the current runs out from the canopy hem 2. In this instance, the water current Sc gives a pressure Pc against the inner surface of the canopy 1, moreover, the water current flows smoothly so that the canopy hem 2 can be kept stable in the deployed form. On the other hand, the canopy which is not provided with the center cord as shown in FIG. 6 causes eddy current when the water current So lashes against the center portion of the canopy, so that the deployed shape of the canopy hem 2 is unsettled due to the pulsation being caused by the change of internal pressure P0 of the canopy 1.

As shown in FIG. 7, the top portion of the canopy 1 and the bottom portion of the canopy are provided with groups of the floats and groups of the weights, respectively, as another means to accelerate the full opening and to stabilize the opening state of the canopy 1.

FIG. 8 is an enlarged perspective view of the portion F in FIG. 7, in which the numeral 4 is the suspension line, the numeral 24 is a tubular band which receives the small weights 26, and the numeral 25 is a cord which is passing through the center hole of each weight 26 in order to retain them. The band 24 and the cord 25 are attached at their both ends to the canopy hem 2 stepping over the suspension line 4 as shown in the figure by means of sewing and the like, and the canopy hem 23 between the both attached portion with the band 24 may be given a little relaxation. The floats at the top portion 2a of the canopy are attached with the same manner as said weights 26, and the tubular bands 24 which hold the floats are shown in FIG. 7.

FIG. 9 is a schematic illustration of the folded canopy which is observed from the side of the canopy hem 2, in which the numeral 24 indicates the tubular band holding the groups of the small weights and the numeral 24' indicates the tubular band holding the groups of the small floats. The relaxation of the hem 2S promotes the initial opening of the canopy, ensures the full opening, and shortens the time required for full opening of the canopy.

In FIG. 10, the numeral 10 is a separator, the numeral 10 is a connecting ring of the suspension lines 4, the numeral 6 is a connecting webbing, the numerals 6 are branches of the webbing 6, the numeral 5 is a center cord, and the numeral 5 is a connecting loop of the center cord 5-. Each of the suspension lines 4 is inserted through each hole 27 of the separator 10 and then each line 4 is joined with the connecting ring 10. Meanwhile, the ends of the branches 6' of the connecting webbing 6 are also joined with said ring 10', and then the separator 10 is slided to the ring 10'.

As shown in FIG. 11 the separator 10 is tied up with the ring 10' by the cords 29 through the small holes 28.

FIG. 12 is a front view of the separator 10 which is viewed from the left side in the drawing of FIG. 11, in which the relational positions of

holes

27 and 28 are shown. The large opening 31 is provided at the center of the separator 10 in order to reduce the weight of the separator 10. This separator 10 is made of rigid materials such as Woods, plastics or metals, and the ring 10' is usually made of flexible nylon webbing and the like.

As the steps to recover the sea anchor of the present invention onto the deck of the vessel after it is employed in practical uses, the pulling line 22 which is connected to the buoys 19 is pulled up first of all, and then the buoys 19, the weight 20 by means of the

connectings

18 and 18, further, the cord 17, the pack 16, the cord 15, the sea anchor body A, the

metal parts

7, 8 and 9, and the towline 21 are pulled up in that order. Thus the sea anchor can be recovered from the sea easily and quickly.

FIG. 13 is the appearance of the sea anchor A which is just after the recovery from the sea. As shown in the figure, the relaxation of the suspension lines 4 are large owing to the existance of the center cord 5, and the suspension lines 4 look like tangled. Accordingly, they must be aligned as shown in FIG. 14. The alignment can be carried out easily and soundly by holding down the hem 2 and pulling the aligning loops 11 which are provided on the outer surface of the canopy 1 or pulling the aligning guide ring 13 which is shown in FIG. 2 by hand. After confirming the alignment of the sea anchor, the sea anchor body A and the accessories are placed in order as illustrated in FIG. 15. The numeral 16 in said figure shows the pack, the

flaps

16a and 16b of which are opened.

FIG. 16 shows the pack 16 in which the sea anchor body A is packed, and the connections of each other of the other parts, and shows also the state of just before the launching of the sea anchor which are distributed on the deck of the vessel.

FIG. 17 is a front view of the pack 16, in which the numeral 16a is a base flap (marked as (9) being provided with a closing loop 162 (see FIG. 18), the numeral 16b denotes flaps which are provided with holes 16 the numeral 160 denotes pockets which are effective in the quick deployment of the contents in the water, and the numeral 16d denotes stays of the pockets 160.

As shown in FIG. 18, the sea anchor body A may be packed into the pack 16 in such orders that the folded canopy 1 is put in the pack 16, and then the aligned suspension lines 4 are folded into the pack 16. Then the separator 10 and the branches 6' of the connecting webbing are put into the pack 16. The flap 16a is then closed, and the flaps 16b are closed in layers on the flap 16a while the loop 16a on the flap 16a is inserted into the holes 16 of the flaps 16b. The order of closing the flaps 16b may be clockwise. Further, the connecting webbing folded in U shape is inserted into the loop 16e, thus the interim locking of the pack 16 can be carried out to be the state as shown in FIG. 16. This pack 16 can contain the largesized sea anchor body A compactly, so that the sea anchor does not obstruct in the vessel when it is not used. And when it is used, it has very elfective performances that the launching and the deployment can be carried out in easy, safe, sure and rapid manner.

The launching of the sea anchor of the present invention can be carried out by the following steps:

The sea anchor arranged as FIG. 16 is placed on the deck of the vessel, one end of the towline 21 and one end of the pulling line 22 are fixed to the bow section of the vessel, one holds the pack 16 and another holds the

shackles

7 and 9, swivel 8 and weight 20 then throw them into the water simultaneously. In the case of a small sea anchor, this step can be carried out by one person. The length of the cord 18 is to be adjusted in advance as somewhat longer than the expected depth in the water so that the sea anchor will be deployed at the depth. After observing the sinking of the pack under the water surface due to the weight 20, the bouys 19 connected with the cord 18 are thrown into the water. At the same time, the towline 21 and pulling line 22 are payed out properly, as the vessel being drifted by the wind from the launching place, the connecting webbing 6 is pulled by the towline 21, and the U shaped portion of the connecting webbing 6 slips out from the loop 16a of the flap 16a of the pack, and thus the pack is unlocked. Then the

flaps

16a and 16b of the pack 16 are opened, the contents of the pack 16, i.e., the sea anchor body is deployed in the proper order while the pack 16 remains at the original position being due to the resistance of the pockets 16c, and the sea anchor becomes the state as shown in FIG. 1 after a short time. The deployment of the sea anchor is thus completed and the normal performance of the sea anchor is attained.

As the sea anchor of the present invention is packed in the above-mentioned pack 16, it can be employed safely and reliably even when it is used in very poor visibility such as in strong wind, dark night, dense fog and the like. Moreover, the deployed canopy 1 retains the deployed shape of the maximum opening diameter owing to the interactions of notches on the periphery of the canopy, groups of the small floats and the weights, vents at the center of the canopy, and the center cord, and the canopy retains the normal state without rotation or revolution, accordingly, the desired effective drag may be obtained. The canopy gives an optimum drag to the vessel according to the wind force, so that the bow faces against the wind and the vessel is free from the side waves, the rolling and yawing of the vessel are decreased, and the inclination of the vessel is reduced. Accordingly, the fatigues of the crew are reduced, recreations of the crew during the stop of operation become very elfective, and breakdowns of catches and appliances are not caused. Further, the velocity of drifting is reduced, so that the distance of drifting of the vessel is shortened even in strong wind and the vessel can be returned to the original position within a short time.

The sea anchor of the present invention may be re covered from the sea only by pulling up the pulling line 22 to haul up the sea anchor, not so much labor is required to recover the sea anchor, re-packing on the deck after the recovery is easy, and the preparation of the next launching can be carried out without difficulty.

As above-mentioned, the present invention provides not only the highly effective sea anchor but also the complete deployment system thereof.

What is claimed is:

1. A sea anchor comprising:

(a) a pack; an attaching cord and a canopy;

(b) one end of said attaching cord connected to said pack and the other end of said attaching cord connected to said canopy;

(c) a plurality of suspension lines and a separator;

((1) one end of said suspension lines being peripherally attached to said canopy and the other ends of said suspension lines being attached to said separator;

(e) A plurality of webbing strips, a first and second shackle, and a swivel;

(f) one end of said webbing strips being attached to said separator in such a manner that when extended, said webbing strips would lie on the opposite side of said separator to the suspension lines similarly attached thereto; the other end of said webbing strips being attached to said first shackle;

(g) one end of said swivel being connected to said first shackle and the other end of said swivel being connected to said second swivel, wherein said pack is of suitable dimensions for containing said attaching cord, said canopy, said plurality of suspension lines, said separator and said webbing strips.

2. A sea anchor in accordance with claim 1, wherein said canopy of said sea anchor has placed therein notches on the periphery thereof and slot vents at the center thereof whereby the shock load on said canopy due to the change of water currents is reduced and the rotations and revolutions of said canopy is prevented.

3. A sea anchor in accordance with claim 1, wherein said canopy comprises:

(a) a plurality of tape stress members, said members being arranged in the form of a segmental framework;

(b) a plurality of membranes disposed upon said tape stress members whereby the canopy is divided into a plurality of small segments, so that there is provided a high strength/weight ratio and any tears developing in said membranes are checked at said tape stress members.

4. A sea anchor according to claim 1, additionally comprising:

(a) a plurality of small floats, said floats being attached to the top hem of said canopy and (b) a plurality of small weights, said small weights being attached to the bottom hem of said canopy, whereby in the deployment of said sea anchor, said deployed anchor is kept in the water in a proper and stable state,

5. A sea anchor according to claim 1, additionally comprising:

(a) a center cord, said cord being joined at one end thereof to the center of said canopy and at the other end thereof to the concurrent point of said suspension lines, whereby the cross section of said canopy is converted into a W-shape.

6. A sea anchor in accordance with claim 1, whereby said separator of said suspension lines are located in a position nearby the concurrent point of said suspension lines.

7. A sea anchor in accordance with claim 1, further comprising:

(a) a guide ring located in such a manner that said attaching cord passes perpendicularly therethrough; (b) a plurality of loop handles disposed upon the convex outer surface of said canopy and (c) a plurality of auxiliary cords connecting said guide ring to said loop handles whereby the repacking of said sea anchor may be facilitated. 8. A sea anchor according to claim 1, wherein said pack comprises:

(a) a pack body, wherein one end of said pack body is open; (b) pockets disposed about the outer surface of said pack body; (c) a plurality of flaps, said flaps being disposed peripherally about said open end of said pack body; (d) a loop, said loop being disposed upon one of said flaps, the remainder of said flaps each having a hole disposed in each, so that when the flaps are folded to close the pack, said holes are located one atop the other and said loop passes through said holes.

References Cited UNITED STATES PATENTS 898,266 9/1908 Rosvold 114-209 2,536,682 1/1951 Frieder et al 114-209 3,039,419 6/1962 Rimar 114209 TRYGVE M. BLIX, Primary Examiner