US3730129A

US3730129A - Extruded cam cleat

Info

Publication number: US3730129A
Application number: US00109143A
Authority: US
Inventors: J Helms
Original assignee: Seahorse Spars and Equipment Ltd
Current assignee: Seahorse Spars and Equipment Ltd
Priority date: 1971-01-25
Filing date: 1971-01-25
Publication date: 1973-05-01
Anticipated expiration: 1990-05-01

Abstract

A cam cleat for releasably holding a rope line or the like against axial slippage comprised of a base plate having pivotally mounted thereon a pair of opposing cam jaws cut from extruded metal or plastic stock having an arcuate cam surface upon which is formed a plurality of wedge-shaped, rope-engaging teeth, the projecting edges of which are rounded upon a uniform and relatively small radius. An axial chamber within each jaw concentrically receives a base plate spindle and an offset chamber provides a detent for both a biasing spring and a pivotlimiting stop. Configuration of the jaw teeth is such that the rear face of each tooth is substantially perpendicular to the arcuate cam surface and a plurality of teeth on each jaw will simultaneously engage a line inserted between opposing cam surfaces. Insertion of the line is facilitated by a chamfer through the upper end of each tooth.

Description

Unite States tet n 1 Helms EXTRUDED CAM CLEAT [75] Inventor: Jack A. Helms, Columbia, SC.

[73] Assignee: Seahorse Spars and Equipment,

Ltd., Suffolk, England [22] Filed: Jan. 25, 1971 [21] Appl. N0.: 109,143

[52] US. Cl ..114/218 [51] ..B63b 21/04 [58] Field ofSearch .ll4/l99,218

[56] References Cited UNITED STATES PATENTS 3,265,032 8/1966 Hume I ..l 14/218 2,627,834 2/1953 Roberts et a1. 14/199 2,608,174 8/1952 Sponenburg l ..l 14/199 3,051,116 8/1962 Weil ..114/199 FOREIGN PATENTS OR APPLICATIONS 1,377,316 7/1963 France ..1l4/2l8 Primary ExaminerEvon C. Blunk Assistant Examiner-W. Scott Carson Attorney-Townsend M. Belser, Jr.

[5 7 ABSTRACT A cam cleat for releasably holding a rope line or the like against axial slippage comprised of a base plate having pivotally mounted thereon a pair of opposing cam jaws cut from extruded metal or plastic stock having an arcuate cam surface upon which is formed a plurality of wedge-shaped, rope-engaging teeth, the projecting edges of which are rounded upon a uniform and relatively small radius. An axial chamber within each jaw concentrically receives a base plate spindle and an offset chamber provides a detent for both a biasing spring and a pivot-limiting stop. Configuration of the jaw teeth is such that the rear face of each tooth is substantially perpendicular to the arcuate cam surface and a plurality of teeth on each jaw will simultaneously engage a line inserted between opposing cam surfaces. Insertion of the line is facilitated by a chamfer through the upper end of each tooth.

7 Claims, 3 Drawing Figures lIIIIIHIIIIIIIHHIIIIHlHIIHT HHIHIHIIIHHHH lilllllll Patented May 1, 1973 m O r e lHiHIHIIHHlHlllHlilHllll HHHHIHIHHIllHlHlllE INVENTOR JACK A. HELMS axraunnn CAM CLEAT BACKGROUND OF INVENTION This invention relates generally to devices for securing rope lines for easy release and more particularly to cam cleats for releasably holding sheets, halyards and other rope lines used on sailboats. Cleats of this type usually consist of at least one pivotally mounted camlike jaw which cooperates with either another pivotal jaw or a fixed abutment to define a line receiving space or nip between opposing cam surfaces on the two parts. The pivotal jaw or jaws are spring-biased so as to frictionally engage a line placed between the cam surfaces. The line to be held in the cleat is inserted by pulling it against its own axial tension while forcing it down between the cam surfaces, causing the pivotable jaw or jaws to rotate against the bias of the spring and separate for a sufficient distance to permit entry of the line. When the pull on the line ceases, it is jammed between the cam surfaces both by the spring bias and by its own tension and is thereby held against reverse axial movement in the direction toward the tensile load. In order to increase the frictional hold of such cleats upon the line, cam surfaces are sometimes serrated with sharp teeth.

Although several cam cleat designs are found in the prior art, such as those illustrated in the patents to Roberts, et al., US. Pat. No. 2,627,834, and to Weil, U.S. Pat. No. 3,051,116, prior art cleats have a number of long-standing disadvantages which are overcome by the present invention. The sheet or other line held by a cleat often must be freed quickly to avoid capsizing the sailboat. One disadvantage encountered with existing cleats is the necessity of pulling the secured line a substantial distance against its full tensile load in order to release it from the cleat. The rapid execution of such a releasing action requires a pulling force of much greater magnitude than the opposing tensile load upon the line. The sharp teeth found on conventional cleats have also proven to be quite objectionable in that release and insertion of the line in such cleats cause a great deal of wear and tear on the line material, requiring frequent replacement of sheets, halyards and other cleated lines.

It is also extremely difficult with conventional cleats to force the line into the jamming space between the cam surfaces. This deficiency is particularly evident in single-handing a sailboat or in sailboat racing where lines must be rapidly secured or adjusted in their cleats, often with only one hand.

Another deficiency encountered is that the jaws of prior art cleats are incapable of positively holding a line against axial movement under repeated applications of tensile loads exceeding 500 pounds. Although some cleats on the market today are capable of initially retaining a fairly high load without line slippage, the load-retaining ability of these cleats drops off sharply with subsequent load applications. Furthermore, the mounting base of prior art cleats will distort under the higher load applications, resulting in rapid deterioration of the cleat structure.

Although a number attempts have been made in the prior art to alleviate certain of the foregoing difficulties, only the applicants invention satisfactorily eliminates all of those disadvantages.

SUMMARY OF INVENTION With the foregoing background and prior art difficulties in mind, a principle object of the present invention is to provide a cam cleat into which a rope line can be readily inserted and from which it can be easily released without cutting the rope and with relatively little wear and tear on frequently cleated lines.

Another object of the present invention is to provide a cleat jaw having a plurality of teeth which simultaneously grip a rope line by biting deeply into the rope material.

Another object of the present invention is to provide a cleat assembly capable of holding a line against axial slippage under repeated applications of high tensile loads throughout the life of the cleat.

It is a further object of the present invention to provide a cleat assembly from which a line can be instantly released while under design tensile loads exceeding 500 pounds.

A further object of the present invention is to provide a cam cleat requiring relatively little axial movement to insert a line between cam surfaces of the cleat jaws.

Another object of the present invention is to provide a cam cleat assembly wherein the base undergoes relatively little distortion under high tensile loading of the line held between the cleat jaws.

Another object of the present invention is to provide a cam cleat jaw having a plurality of wedge-shaped teeth with sharply rounded rope-engaging edges formed by extruding the jaw stock from a die opening having the same shape as the cross-section of the jaw perpendicular to its pivotal axis.

In addition to the numerous advantages apparent from the foregoing discussion, the present invention has the further advantages of simplicity in construction, economy of manufacture, and ruggedness and durability in use. Furthermore, the apparatus of the present invention can be constructed using conventional manufacturing techniques and can be easily assembled from relatively few parts. The exact nature of the invention as well as other objects and advantages thereof will be readily apparent from the annexed drawing and the following specific description of the preferred embodiment of the invention.

DESCRIPTION OF DRAWINGS For a better understanding of the present invention, reference is made to the accompanying drawing in which:

FIG. 1 is a plan view of the cam cleat with a fragmentary section showing the internal structure of the right cam aw.

FIG. 2 is a front sectional elevation of the cam cleat taken on line 2-2 of FIG. 1.

FIG. 3 is a plan view of the cam cleat showing a rope line held between its jaws and illustrating its operation.

DETAILED DESCRIPTION OF INVENTION Referring now to the drawing and particularly to FIG. 2, there is illustrated one form of the extruded cam cleat made according to the teachings of the present invention. The cleat assembly, generally designated 10, includes an elongated substantially flat base plate 12 upon which two

jaw spindles

14 and 15 are rigidly mounted, one near each end of the base plate 12 on an axis normal to its flat surface. Although

spindles

14 and 15 may be separate components, they are preferrably formed as an integral part of the plate 12, the spindles and the plate being integrally molded from a glass-filled nylon type plastic. A bore 16 runs down the central axis of each spindle and around the spindle base adjacent to the plate is an outer concentric ledge 18.

Pivotally mounted upon spindles l4 and 15 are left cam jaw 20 and right cam jaw 21, respectively. The construction and operation of each jaw is identical except that one is the mirror image of the other. Therefore, the design details and mounting structure of only the left jaw will be specifically discussed. The remaining reference numerals for the left jaw structure are the same as those for the right with the latter being designated by a prime symbol.

The cam jaw 20 has an axial bore 22 and a connecting internal chamber 23 concentric to its pivotal axis. The bore 22 rotatably receives the upper end of spindle 14 and the lower portion of axial chamber 23 similarly receives concentric ledge 18, bore 22 cooperating-with the spindle and chamber 23 cooperating with ledge 18 in journal-like fashion during rotation of the cam jaw about the spindle axis. Jaw 20 is positively biased toward jaw 21 by a spring means 26 housed within the upper portion of axial chamber 23. Spring means 26 is preferrably of the helical type with its coils arranged concentrically about the middle portion of spindle 14. The helical spring 26 is anchored at its lower end by means of a bent tang 28 which fits within a hole 29 in the upper surface of ledge 18. At the upper end of the spring is a hook-like projection 30 which engages the forward wall of an offset jaw chamber 24 so as to bias the left cam jaw in a clockwise direction as best shown by the dotted outline of the spring in FIG. 1. The mirror image structure for the right cam jaw 21 is clearly shown in the cut-a-way portion of FIG. 1, the right jaw being biased by its spring 26' in a counter-clockwise direction toward the left jaw. Both jaws are constantly biased toward the rest position shown in FIG. 1.

Located on the periphery of spindle ledge 18 and formed integrally therewith is a stop 32 which cooperates with opposing faces of offset chamber 24 to control the are through which the cam jaw can rotate or swing about the spindle. When engaging the rear wall of the chamber, the stop positions the jaw to receive the line and prevents the jaw from being turned inside out and damaged. When engaging the opposite or forward wall, the stop limits the backward swing of the jaw to approximately one-eighth of a turn to prevent over-stressing the spring. Although preferrably molded as part of the concentric ledge 18, the stop may consist of a separate stud or stop element mounted upon base plate 12 so as to project into offset chamber 24. By using a separate chamber for the stop element instead of a single chamber for all internal parts, approximately two-thirds of ledge 18 may be closely surrounded by axial chamber 23, providing a strong journal structure adjacent to the cam base which supplements the journal structure at bore 22 so as to accurately position the rope-engaging portions of the cam jaw and prevent tilting and other distortions of the jaw about its axis at the higher rope loads.

The cam jaw is rotatably secured upon its spindle by means of a washer 34 fastened in position by a bolt 36 passing through the washer bore and the bore 16 of the spindle. The tapered head 38 of the bolt fits flush into a correspondingly tapered counterbore 40 in the washer 34. Bolthead 38 has the usual slot 42 for the flat tip of a screwdriver. A concentric counterbore 44 in the underside of the washer 34 locks it in position on the top of spindle 14 as illustrated in FIG. 2. Base plate 12 has a similar concentric counterbore 48 to receive a nut 50 which is tightened on the threaded shank 52 of bolt 36 to retain all of the cam jaw components in place as shown in the drawing.

As seen in FIG. 2, it should be noted that the height of the spindles is sufficiently greater than the thickness of the jaws and the depth of counterbore 44 to allow the jaws to rotate freely in the vertical space between the underside of bearing washer 34 and the upper surface of plate 12. With the cam jaw components held in position by nut 50, the length of bolt shank 52 may vary and is usually determined by the thickness of the boat deck or other structure upon which the cleat is to be mounted. In the usual situation, the length of the bolt shank is such that it protrudes a short distance from the reverse side of the structure to which the cleat is to be secured and a conventional lock washer and a second nut similar to nut 50 is threaded on its protruding end. Base plate 12 may contain auxiliary countersunk bolt holes, such as at 54, for such additional fastening bolts as may be desired. Jaw bolts 36 may consist of conventional 3/16 inch stainless steel bolts 3 inches in length, while 3/16 inch stainless steel bolts 2 inches long will usually suffice for any auxiliary bolts required.

With reference to the exterior structure and design of the cam jaws as best illustrated in FIG. 3, a plurality of rope-engaging teeth 62 are formed on the cam surface or inner periphery 60 of jaw 20. By reason of the arcuate shape of periphery 60, the tips T of the jaw teeth define a smooth cam are A having a radius R and a geometric center C. Although point C is also the geometric center of the arc of periphery 60 in the preferred embodiment, the radius R and tooth depths are the controlling parameters. Both the cam arc and the design and arrangement of the rope-engaging teeth constitute important features of the present invention.

Defining the longitudinal axis of the jaw as an imaginary line bisecting the are A and passing through the jaws pivotal axis X, the arc center C is eccentrically located to the rear of the longitudinal axis and to the outside of the transverse axis. (In the drawing, the longitudinal axis intersects at the tip of the fourth tooth from the front of the jaws shown). The rearward spacing approximates one-third of the radius R and the outward spacing one-sixth of that radius in the preferred embodiment. However, rearward spacing in the range of onesixth to one-half R and outward spacing in the range of zero to one-third R is acceptable. This location of arc center C gives a relatively flat cam arc allowing at least four teeth of each jaw to firmly grip the line while still providing sufficient curvature for the cleat to operate satisfactorily with lines of various diameters and materials.

Each of the

teeth

62 and 62 are of identical construction, the arrangement of teeth 62' on the right jaw 21 merely being the reverse or mirror image of the array of teeth 62 on left jaw 20. The specific design and manufacture of those teeth constitute an important part of the invention. Each tooth is substantially in the shape of a right-angled wedge with its rectangular base curvilinearly resting upon the cam periphery so that the thin edge or tip T of the wedge is normal to the base plate 12 and projects inwardly to form a narrow ropeengaging ridge. Each wedge-shaped tooth has its right or major angle located toward the rear of the jaw so that all of the rear tooth faces B fall substantially on radial lines of the cam arc. It has been found that the foregoing arrangement and design of cam jaw teeth greatly improve the line gripping characteristics of the cleat. Without being bound by any one theory of operation, it is felt that the improved performance of the present invention is due in part to the disposition of the rear tooth face B in a plane approximately perpendicular to the relatively flat cam arc A. In that position, the rear face bites almost straight into the cleated line as illustrated in FIG. 3. Although the major wedge angle is preferrably 90 as measured to the arc tangent at the base of rear face B, small variations in the range of 85 to 95 do not appreciably effect the tooth grip. In the preferred embodiment shown, the rear face of the last rearward tooth is a continuation of the rear jaw surface 64 such that the eccentric center C falls on an imaginary line extended in the plane of that jaw surface.

The forward face F of the tooth wedge makes an acute angle to the arc tangent where it intersects periphery 60. Although the slope of face F is not particularly critical, the acute forward angle should not be less than 45 so that adjacent teeth will be spaced relatively closely and the depth of the teeth will be sufficient to prevent rope fibers or other line material from reaching the bottom of intervening tooth crevices. Due to the pliable nature of most cotton or nylon ropes and flexible lines of other materials, the depth of face B should be at least one-sixteenth inch, a depth of five thirty-seconds inch being preferred.

The thin edge or ridge forming the tip T of each tooth is accurately rounded on a relatively small radius of approximately mils one one-hundredth inch). I have found that by uniformly rounding off the biting edges of the jaw teeth in this fashion, wear and tear on the line is practically eliminated without impairing the gripping characteristics of the teeth. When compared with conventional cleats, the cam cleat of the present invention is actually capable of holding a line against slippage under tensile loads significantly exceeding those which have resulted in slippage through a conventional cleat with sharp-edged teeth. Furthermore, while the retaining ability of conventional cleats drops off sharply with repeated loadings, that of the instant cleat remains substantially constant. Conventional sharp-toothed cleats also cut and damaged the line considerably, which does not occur with the novel cleat disclosed. Rounded edges on the teeth further alleviate the problem of releasing a highly loaded line from the cleat, only a sharply applied vertical force of relatively small magnitude being required to pull the line from betweenthe cam jaws of the present invention.

Although edges rounded on a radius of 10 mils appear to give best results, satisfactory performance is realized where tip radii are within the range of 5 to 30 mils. Although I have attempted to make my cam jaw by molding and other manufacturing processes, jaw

teeth having the small tip radius desired could only be produced by extruding the metal or plastic jaw material through a die opening having the same cross section as the major plane of the cam jaw, i.e., the cam jaw cross section normal to its pivotal axis as seen in FIGS. 1 and 3. The extrusion process of manufacture further facilitates mass production of the cleat jaws as a large number of individual jaw blanks of the desired thickness are cut from a single extruded bar of jaw stock. After each cam jaw blank is cut from the jaw stock, it is machined to produce the final cam cleat jaw by drilling the spindle bore and cutting out the axial and offset chambers.

Chambers

23 and 24 are bored from one side of a blank to produce a left jaw 20 and chambers 23 and 24' are bored from the opposite side of a blank to produce a right jaw 21.

As a further refinement of my novel cam cleat jaw, the upper ends of the jaw teeth may be beveled to provide chamfer K along and adjacent to jaw periphery 60. The chamfer on the left jaw cooperates with that on the right jaw to provide an entrance notch above the ropeengaging area between opposing teeth as illustrated in FIG. 2. The chamfer is preferrably beveled as a 45 cone-like surface which follows cam are A and intersects curved periphery 60 at the upper end of each tooth base. The V-shaped entrance notch greatly facilitates entry of the line in between the tips of the jaw teeth. A line placed in the notch frictionally engages a relatively large portion of the chamfered surface such that only a short rearward movement of the line L is required to rotate the cam elements a sufficient distance apart to permit entrance of the line into the resulting space between the teeth. Upon movement of the line down into the engaging space, reverse axial movement in the direction of its tensile force F (indicated by an arrow in FIG. 3) rotates the jaws together and forcefully jams the jaw teeth into the line, securely holding it against further reverse axial movement. Entrance of a line between the teeth is further facilitated by their smooth rounded tips T. Throughout the cleating operation the jaw teeth remain in contact with the line by reason of the biasing action of helical springs 26 and 26'.

Cleat base 12 and

spindles

14 and 15 may be integrally molded from any suitable material, such as a nylon type plastic filled with glass fibers. Carbon black or other pigments may also be added to give the base material the desired color.

The dimensions of the preferred embodiment are described more fully in the following paragraphs. Base 12 may have an overall length of 3 inches and a width defined by semicircular outer ends of inch radius. A base thickness of one-fourth inch supports two identical spindles having an overall height above the base of eleven-sixteenths inch and a diameter of one-half inch. Concentric ledges 18 and 18' are oneeighth inch in height and twenty-five thirty-seconds inch in diameter. A semicircular nodule three thirtyseconds inch in radius on the ledge periphery serves as stop 32, the center of the semicircle being located around the ledge periphery on a radial line of the spindle axis at an angle of approximately 60 from the longitudinal axis of the base. Spindle bore 16 has an inside diameter of thirteen sixty-fourths inch, and the same diameter is used for auxiliary bolt holes such as 5 Concentric recess 48 on the underside of the base is three thirtyaseconds inch in depth and seventeen thirtyseconds inch in diameter.

Spring means 26 consists of a helical spring made from 1/16 inch spring metal stock wound at a diameter of three-fourths inch. A 1/4 inch section was bent at each end of the spring as shown in FIGS. 1 and 2 of the drawing to form hook-

like tangs

28 and 30.

Jaw blanks five-eighths inch thick are cut from a bar of extruded aluminum stock having a maximum crosssectional dimension of 1 inches as measured on an overall dimension line parallel to rear surface 64 and extending from the tip of the last rear tooth to a point opposite where the outer jaw periphery 66 intersects the longitudinal jaw axis. The overall transverse width of the jaw blank is 1 Va inches as defined by the radius of the outer semicircular periphery 66 which has its geometric center at the jaw pivotal axis X, that radius being approximately one-third to one-fourth of said maximum jaw dimension, or preferrably nine-sixteenths inch. Cam are A is defined by a smooth arc having a radius R of 1 15/32 inches as measured from the eccentric center C. The wedge-shaped jaw teeth 62 are formed by extruding the jaw stock through a die opening with tooth forming surfaces comprised of V-shaped notches rounded at the bottom and giving wedge apex angles of 35, perpendicular tooth depths of five thirtyseconds inch, and a uniform arc spacing between tips T of approximately 5 W. The preferred extrusion die produces jaw stock having a total of eight teeth with their tips T uniformly rounded on a radius of mils.

Two identical jaw blanks are machined on opposite sides to produce a right and a left cam jaw, the machined side being referred to here as the underside. First, a 17/32 inch diameter bore 22 is drilled out along the pivotal jaw axis X and then the outside or axial chamber 23 is counterbored from the underside of the jaw at a diameter of thirteen-sixteenths inch, leaving an exterior chamber wall approximately five thirty seconds inch in thickness. Next, the inner or offset chamber 24 is bored out from the same direction at a diameter of twenty-one thirtyseconds inch and on a center located thirteen thirty-seconds inch along a radial line extending from pivotal axis X (a distance equal to the radius of chamber 23) at an angle of about to to the longitudinal jaw axis. The extruded cross section of the jaw is such that the eccentric center C is in the same plane as the rear surface B of the rearmost tooth and the rear jaw surface 64, both of those surfaces being parallel to the longitudinal axis of the jaw. The location and dimensions of offset chamber 24 should provide an adequate surrounding wall thickness while at the same time allowing for a satisfactory range of motion about stop 32. As the final machining step, the upper ends of teeth 62 are beveled along a conical surface disposed at an angle of 45 to the jaw axis and intersecting the arc of periphery 60 at the base of the teeth.

After molding the base 10 and machining the

cam jaws

20 and 21 as outlined above, spring 26 is mounted upon the base and the cam cleat assembled as shown in FIG. 2, the various parts being secured in position by means of washer 34, bolt 36 and nut 50. Washer 34 may also be molded from a glass-filled plastic of the type used for base 12. The overall diameter of washer 34 is 1 inch with a thickness of five thirty-seconds inch. Countersunk hole 40 has a diameter of thirteen sixtyfourths inch at the bottom and three-eighths inch at the top and counterbored recess 44 is one thirty-second inch deep with a diameter of seventeen thirty-seconds inch. Standard 3/16 inch stainless steel bolts and nuts are utilized in the preferred cam cleat assembly.

The cleat described above is specifically designed for a inch line. However, it will work satisfactorily with lines having diameters in the range of three-sixteenths to one-half inch. In making cleats for such small diameter lines, the distance between the spindles and the peripheral angle between stop 32 and the longitudinal axis of the base may be selected so that in the rest position the cleat jaws are pivoted approximately 5 toward the rear as measured between the longitudinal axis of the jaw and that of the base. This modification increases the number of interlocking teeth when the jaws are in their rest position and insures that the maximum number will engage a small line placed between the jaws. As shown in FIGS. 1 and 3, the upper surface of the base below and adjacent to the rear face of each jaw may also slant approximately 5 to the rear in order to increase the upward support under rearwardly pivoted jaws.

Although in the preferred embodiment, the left and right stops are both located in the same position, either stop may be advanced several degrees to the rear of the other so that the rear jaw teeth will interlock'in the same position each time the rope is removed. Even though the right jaw 21 is shown slightly advanced to the rear in FIG. 1, stops 32 and 32 are actually equal so that the rear teeth will interlock at random upon removal of a cleated line. Such random interlocking is preferred so that the interlocking teeth on each jaw wear uniformly over the life of the cleat.

Although but a single embodiment has been described in detail, other embodiments and variations such as those suggested above will occur to persons skilled in the art. It is possible, of course, to use various features of the specific embodiment described, either separately or in various combinations, and such uses are within the contemplation of the present invention. Furthermore, many structural changes are possible and are intended to be within the scope of this disclosure. It

is also to be understood that the drawing and specificaof said pivotal axis, said cam jaw having an upper axial bore and a lower internal chamber of cylin drical cross-section communicating axially with said upper bore, both said bore and said internal chamber being located concentric to the pivotal axis of said jaw and said internal chamber being adapted to house the biasing portion of a spring means;

c. spindle means adapted to mount the cam jaw upon the supporting surface of said base with one edge of the cam periphery adjacent thereto and to journal said jaw for rotation about its pivotal axis and including a spindle shaft having an upper bearing surface and a cylindrical ledge concentric to the base of said shaft and adapted to provide a lower bearing surface, the axial bore of said cam jaw receiving and bearing upon the upper bearing surface of said spindle and a portion of the internal concentric chamber of said jaw receiving and bearing upon the lower bearing surface of said concentric ledge for pivotal rotation of said cam J a plurality of wedge-shaped jaw teeth curvilinearly mounted upon said cam periphery with one end of the wedge adjacent to the supporting surface of said base, each of said teeth having a major angle contiguous to and toward the rear of said periphery and its small edge spaced from said periphery and accurately rounded on a uniformly small radius to form a smooth line engaging ridge along the projecting tip of the tooth, the angle between wedge faces adjacent to said small edge providing a rear wedge face of substantial depth and the arc radius of said cam periphery bringing the tips of said plurality of teeth simultaneously into frictional engagement with a secured line;

e. opposing line engaging means mounted upon said base opposite to said cam periphery and adapted to cooperate with said cam jaw to hold a line between said jaw periphery and said engaging means by jamming it onto the rounded tips of said plurality of cam jaw teeth;

f. and spring means housed within said internal jaw chamber and adapted to be anchored to said spindle means and to bias said jaw toward said opposing line engaging means.

2. A cam cleat as claimed in claim 1 wherein a cam jaw stop means is mounted upon said concentric ledge and said cam jaw includes a second internal chamber offset from said concentric chamber and adapted to cooperate with said stop means to limit the rotational are through which said jaw may pivot about said concentric ledge and to act as a detent for receiving and retaining the biasing end of said spring means.

3'. A cam cleat as claimed in claim 1 wherein said opposing line engaging means is comprised of a second cam jaw having a mirror image structure of said first cam jaw.

4. A cam cleat as claimed in claim 1 wherein the length of said wedge-shaped teeth is equal to or less than the thickness of the cam periphery upon which they are mounted and the ends of said teeth away from said supporting surface of the cleat base have a chamfer substantially intersecting the cam periphery at the base of said tooth ends at an acute angle of less than to the eccentric axis of said cam periphery.

5. A cam cleat as claimed in claim 1 wherein the concentric ledge of said spindle means is rigidly mounted upon said base as an integrally formed cylinder projecting outward from the outer supporting surface of said base.

6. A cam cleat as claimed in claim 1 wherein said spindle means includes cam jaw fastening means comprised of a concentric washer having an aperture through the center thereof and a counterbored recess concentric to and communicating with said aperture from the underside of said washer, said recess being adapted to receive the upper end of said spindle shaft so as to center and lock said washer thereon and the underside of said washer having a bearing surface adapted to bear upon a substantial area of the upper surface of said cam jaw, said washer bearing surface and the counterbored recess cooperating to resist upward cam jaw movement during tensile loading of flexible line secured therein; and a bolt means adapted to pass through said washer aperture, said spindle shaft and said base to secure the cam jaw upon said spindle between said washer bearing surface and the supporting surface of said base, said spindle shaft being of sufficient length to provide space between said bearing and supporting surfaces to permit free rotation of the cam cleat jaw.

7. A cam cleat as claimed in claim 6 wherein said base has a counterbored recess on its underside concentric to said bolt means and said bolt means includes a shank and nut member, said nut member being located completely within said recess so as not to interfere with the mounting of the cam cleat base and coacting with said shank to secure said cam jaw in operative position upon said spindle before said base is fastened to its mounting structure.

Claims

1. A cam cleat for securing flexible lines against forward axial movement toward a source of tension comprising: a. a base adapted to be fastened to a mounting structure and having an outer supporting surface; b. a cam jaw having a pivotal axis and an accurate cam periphery about an eccentric axis to the rear of said pivotal axis, said cam jaw having an upper axial bore and a lower internal chamber of cylindrical cross-section communicating axially with said upper bore, both said bore and said internal chamber being located concentric to the pivotal axis of said jaw and said internal chamber being adapted to house the biasing portion of a spring means; c. spindle means adapted to mount the cam jaw upon the supporting surface of said base with one edge of the cam periphery adjacent thereto and to journal said jaw for rotation about its pivotal axis and including a spindle shaft having an upper bearing surface and a cylindrical ledge concentric to the base of said shaft and adapted to provide a lower bearing surface, the axial bore of said cam jaw receiving and bearing upon the upper bearing surface of said spindle and a portion of the internal concentric chamber of said jaw receiving and bearing upon the lower bearing surface of said concentric ledge for pivotal rotation of said cam jaw; d. a plurality of wedge-shaped jaw teeth curvilinearly mounted upon said cam periphery with one end of the wedge adjacent to the supporting surface of said base, each of said teeth having a major angle contiguous to and toward the rear of said periphery and its small edge spaced from said periphery and accurately rounded on a uniformly small radius to form a smooth line engaging ridge along the projecting tip of the tooth, the angle between wedge faces adjacent to said small edge providing a rear wedge face of substantial depth and the arc radius of said cam periphery bringing the tips of said plurality of teeth simultaneously into frictional engagement with a secured line; e. opposing line engaging means mounted upon said base opposite to said cam periphery and adapted to cooperate with said cam jaw to hold a line between said jaw periphery and said engaging means by jamming it onto the rounded tips of said plurality of cam jaw teeth; f. and spring means housed within said internal jaw chamber and adapted to be anchored to said spindle means and to bias said jaw toward said opposing line engaging means.

2. A cam cleat as claimed in claim 1 wherein a cam jaw stop means is mounted upon said concentric ledge and said cam jaw includes a second internal chamber offset from said concentric chamber and adapted to cooperate with said stop means to limit the rotational arc through which said jaw may pivot about said concentric ledge and to act as a detent for receiving and retaining the biasing end of said spring means.

3. A cam cleat as claimed in claim 1 wherein said opposing line engaging means is comprised of a second cam jaw having a mirror image structure of said first cam jaw.

4. A cam cleat as claimed in claim 1 wherein the length of said wedge-shaped teeth is equal to or less than the thickness of the cam periphery upon which they are mounted and the ends of said teeth away from said supporting surface of the cleat base have a chamfer substantially intersecting the cam periphery at the base of said tooth ends at an acute angle of less than 80* to the eccentric axis of said cam periphery.