US2496315A - Anchor - Google Patents

Description

Feb 7, W51) H. P. SHIPLEY 2,4

ANCHOR Filed April 15, 1944 2 Sheets-Sheet l INVENTOR HABDW/CK P ju/PLE BY 'ATTO EY Patented Feb. 7, 1950 Hardwick Price Shipley, Falls Church, Va.

Application April 15, 1944, Serial No. 531,239

1 Claim.

(Grantedunder the act of March '3, 1883, as amended April 30, 1928; 370 0. G. 757) This invention relates to anchors and more specifically to anchors for water-borne vessels.

In general it is an object of the invention to provide a device which is simple of construction, easily and readily manufactured, prompt and efficient in operation, sturdy and of long life.

Another obiect of the invention is to provide an anchor which has a positive digging-in function prior to the gripping of the fiukes which assists the latter and which positively rotates the flukes to an init al gripping position and positively increases their gripping position to the optimum position for holding so that they do not pull out of the ground; to provide means for such prel minary digging-in which are of extreme simplicity and which do not clog, and to provide such means which also control the maximum flukeshank angle.

Another obiect is to provide an anchor with a stock which may be used at the crown or at the forward end whereby the stock is interchangeable and may be used at either end of the shank therebv permitting hawse-pipe stowage when the stock is in the after end and increased efiiciency with the stock at the forward end. especially in the latter case when used with anchor cables of inadequate we ght such as fiber and wire ropes, the weight of the stock tending to hold the shank hor vontal.

Other objects of the invention will. in part, be obvious and will, in part. appear hereinafter.

The invention accordingly comprises articles of manufacture possessing the features, properties and relation of elements that will be exemplified in the articles hereinafter described, the scope of the application of which will be indicated in the claims.

For a better understanding of the invention, reference should be had to the following description taken in connection with the drawing, in which:

Fig. 1 is a plan view of an anchor embodying one form of the invention;

Fig. 2 is aside View of the anchor shown in Fig. l, the crown and the stock being shown in cross section;

Fig. 3 is an after end View of the anchor shown in Fi 1;

Figs. 4-6 are views, similar to those of Figs. 1-3, of a modification of the anchor shown in Figs. 13; and

Fig. 7 is a perspective view of another modification.

When an anchor is first pulled along the surface of a sea bed into which it is to grip there is a tendency for the flukes to ride along, that surface. There is no gripping untll their forward edges do out down into thatsurface and when the cutting-in is left to. chance it .has been found that an anchor may be pulled a considerable distance before it begins to operate and in some instances it may pull out even after it has once started to grip. The anchors described below have special parts, which, by providing a rotational moment, force the forward fluke edges to assume an angle such that they are forced down into the ground by the reactionary force of the ground as the anchor is pulled forward. They are not only brought to that angle but that angle is increased by the action of those parts until the fiukes finally have so much of their forward faces under the surface that their own action causes them to sink deeper and deeper to give a complete grip.

In Figs. 1-3,, 10 denotes a shank having, at right angle therethrough, an aperture I2 at the forward end and an aperture I4 at the after end, each adapted to receive therethrough a stock IE. Flukes [8 are attached to and integral with a crown 20 which comprises two side pieces 22 more or less parallel with the shank and positioned one on each side thereof. Apertures 24 in side pieces 22 are aligned with aperture M. The stock extends through apertures l4 and 24. The fiukes and crown are oscillatable about the stock, as is the shank, and independently thereof. When the stockis at the forward end of the shank an. axle piece may take its place at the after end. When the plane of the fiukes is parallel with the longitudinal axis of the shank, the position of all of said parts is called, herein, neutral. As shown in Figs. 2 and 5 the center of gravity of the crown in neutral position is at least as far forward as its axis of oscillation.

On each side of the shank and connecting the two side pieces 22 of the crown are digging elements 26 each of which has an inner surface 28. The latter surfaces define a dihedral angle of from about 30 to about and preferably about 60. Their after edges are spaced from each oth-. er and from any central after cross piece 30 which may be present between the side pieces. The forward edges of elements 26 may be sharpened. This assists the digging in.

.Extending inwardly from each surface 28 or preferably, and as shown, extending toward those facesand integral with the shank are protuberances 32, each having a surface against which the respective surface 28, seats. The height of the protuberance is such that, when surface 28 seats thereagainst, the other surface 28 is at an angle in the range of about 3080, preferably about 60, with the longitudinal axis of the shank and the fiukes are beneath and at an angle of between 20-1-0, preferably 30, with the shank. The bearing surfaces of the'pr'otuberances 32 may be broader than the main body thereof; i. e., the protuberances may be'streamlined, as shown in Fig. 3, to permit the ready passage thereby of ground material.

The operation of the above anchor is as follows. The anchor is deposited upon the ground or sea bed. The forward tips of the nukes drop just be low the shank until they touch the ground, but do not necessarily grip since they make an angle of only 15 with the horizontal ground-line.. The forward edges of digging elements 25 are against the ground, the surfaces 28 making a total of 45 angle with the ground (30 plus the 15 which the crown has been tipped by the 15 drop of the flukes to which the crown attached).

As a forward force is imparted to the anchor, the surface 28, being atv said angle of about 45 with the horizontal ground-line, aided by its sharpened forward edge, begins to penetrate. As penetration of the ground by surface 28 proceeds, the reaction of the ground on said surface creates a torque on the crown and attached fiu-kes tending to rotate the flukes, about the stock or pivot pin, downward into the ground. After this initial engagement of the flukes has been accomplished, the torque developed by the action of the ground on surface 23 combines with the torque due to the downward component of the ground force on the nukes and assists in rotating said fiukes into their final operative angular position of approximately 30 with the centerline of the shank.

Since the resistance to forward motion of a flat surface in the ground is obviously a function of its area projecting onto a vertical plane, it can be seen that the resistance to forward motion of a, surface of given area increases as the plane of the surface approaches the vertical. Hence, since the surface 28 assumes, preferably, an angle of approximately 60 with the horizontal when the flukes, are in their final operative position, said surface provides an important supplementary source of holdingpower, when the fiukes are in said final operative position.

During the action described above, which cul-' minates in said final operative position, clogging of the crown has been prevented because the after edges of the surfaces 28 are widely displaced from each other and other internal obstructions to permit ground material to pass through the crown during the brief forward and downward disposition of the anchor to final gripping position. As shown in Fig. 2 that portion of the operative surface 28 which is nearest to the rocking axis of the crown is still spaced away from the rocking axis by a distance which is greater than the projected area of the digging element fit. Should the foremost and rearmost edges of the digging element 25 be projected onto a plane perpendicular to the plane of the flukes,

it will be found that the distance measured a ong the perpendicular plane between the projections of these edges is less than the narrowest part of the passageway through the crown; namely, that part of the passageway defined by the distance from the rocking axis of the crown to the rearmost edge of surface 28. Experimentation wit various size models and with actual anchors have shown that this relation. between the projected size of the digging element and the size of the passageway through the crown is necessary to enable the free movement. through the crown, of the material dug up by the element 26. The passageway may vary with various weight ans chors, but in all cases the passageway, in its narrowest portion, remains largerthan the projected area of element 26.

4 In Figs. 4-6 there is shown a modification in which there areno protuberances but the function of the latteris provided by a surface 34 on cross elements 35 which extend between the side 5 pieces 22. The surfaces 34 are similar to surfaces 28 except that they form a dihedral angle, the apex of which is spaced from the dihedral angle apex of the surface 28 and coincident with the centerline of the flukes and in the region of and normally slightly aft of the axis of the apertures I14. As a result, when the flukes rotate to a position below the shank, surface 34 ap proaches and abuts against the upper surface of the shank which may be taken parallel to the shank'longitudinal axis. At such latter time the plane of" the 'fiul'ses is at approximately 30 with that shank axis. angle between surfaces 35, and theshank surface positi'o-n may be varied inter se in different anchors so that the maximum fluke-shank angle is 30". Clogging about elements 36 is prevented by the fact that r their after e 1:

The operation of the anchor of Figs. 4-6 is evident when the design and operation of the anchor of Figs. 1-3 is considered.

In Fig. 7 there is shown a modified crown havingan I-shaped structure above and an Ishaped structure below the shank. The digging in surfaces I28 are at an angle with each other of approximately 60", and the angle-limiting surfaces $35 perform the functions of surfaces 28 and 34 of the anchor in Figs. 4-6 and are similarly oriented. The surfaces E23 and I34 are provided by the I-shaped structures as shown.

The invention described herein may be manufacturecland used by or for the Government of the United States of America for governmental purposes without the payment of any royalties thereon or therefor.

What I claim as new is:

An anchor comprising a shank, and acre-W1: escillatable with said a pair of sur.

that slope rearwardly to face each other, of surfaces similar to sai. first pair exccp the apex of the dihedral angle of t.-. is spaced from thepair and is struoture'bei'o said shank.

I-IARDWICK PRICE SHIPLEY. REFERENCES CITED The following references file of this patent:

Uh PATENTS I of record in Number Name Date I'l -3,929 Fewkes Feb. 22, 1876. 3 4,149 Pettes Mar. 17, 1885 481,782 Chrietzberg Aug. 30, 1892 to 567,680 Hous Sept. 15, 1896. 695,711 Eynon Mar. 18, 1902 913,367 Downie Feb. 23, 1909 2,249,546 Danforth July 15, 1941 2,279,302 Craig Apr. 14, 1942 .PABETEHTS Nimiber Cou try Bate J 205.140 Great Britain Oct. 10, 1923 264,142 Great Britain Dec. 16, 1926' in 371,381 Germany Mar. 15, 1923 The dihedral axis position, the

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