US2209007A - Shackle - Google Patents

Description

Patented July 23, 1940 PATENT OFFICE snAcKLE William Stevenson, Blundellsands, Liverpool,

l England Application July 21, 1939, Serial No. 285,781

` Claims. (Cl. 59-86) This invention is for improvements in or relating to shackles and is concerned with the type of shackle which is U-shaped and has holes or eyes in the ends of the jaws through which a closure pin or the like is passed, one end of the closure pin being screw-threaded to screw into a correu spondingly threaded eye in` the shackle so that the shackle is closed whenthis pin is `screwed home.

Shackles of the aforesaid type are often used for connecting ropes and chains in marine work. One difficulty which often arises in such work is that the operator connecting up the coupling has to use both hands to bring the part which is attached to the shackle and the other part which is to be located between the shackle jaws together so that time is wasted in manipulating the pin into alignment and engagement with the eyes. Another difculty which often arises with screw-threaded shackle pins is that the pins drop out during making and connection of a coupling and the threads become damaged.

One object of the invention is to provide a simple construction of shackle and pin which will obviate the aforesaid diiculties.

Accordingly the present invention provides a shackle of the type above descrbed in which the closure pin is restrained when the shackle is open, from completewithdrawal from the shackle eyes by an abutment on the pin co-operating with a stop on the shackle. Preferably the abutment is spaced apart from its cci-operating stop by an amount which permits the end of the pin to be retracted into that eye of the shackle which is remote from the end of the pin when the latter is in the closed position.

According to a further feature of the invention there is provided a shackle of the type described wherein an abutment is located on the pin so that it lies against the interior face of one jaw (when the pin is in the closed position) and wherein the interior face of the other jaw is recessed towards its exterior face, the base oi the said recess forming a stop for the abutment, whereby the abutment may be accommodated in the said recess when the shackle is opened. Conveniently the abutment is spaced from the base of the recess by a distance which is substantially equal to the distance between the head of the pin and the start of the thread remote from such head. In the accompanying drawing which shows various forms of the invention by Way of example:

Figure 1 is a part-sectional elevation of a shackle with the closure pin in the closed posi- Figure 2 is a sectional elevation on the lin II-lI of Figure 1;

Figure 3 is a fragmentary detailed sectional elevation to an enlarged scale of the shackle pin adjacent the threaded end ofthe shank and showing one method of constructing an abutment;

Figure 4 is a sectional elevation onthe line V-IV of Figure 3;

`Figure 5 is a view similar to Figure 3 but showing an alternative method of forming the abutment;

Figure 6` is a sectional elevation on the line VI--VI of Figure 5;

Figure 7 is a similar view to Figure 3 showing a further alternative construction of the abut-` ment;

Figure 8 is a sectional elevation on the line VIII-VIII of Figure 7; I

Figure 9 is a part-sectional elevation of a shackle having one threaded eyelet hole and a correspondingly threaded pin;

Figure 10 is a fragmentary detailed sectional view of a modified form of abutment on the pin; and

Figure 11 is a part-sectional view of the ends of the shackle jaws with a modied form of pin closing the jaws.

Figure 12 is a part-sectional view of a modied spring abutment.

The shackle shown in Figures 1 and 2 is of the common inverted U-form, the jaws IIJ of which have eyes I'I and I2 formed in the ends thereof and in alignment to receive a closure pin` I3.

The eyes II and I2 are of different internal diameters, and are screw-threaded respectively at I4 and I5.

Theclosure pin I3 has one end` I6 screwthreaded to engage with the eye I I, and the other end Il of larger diameter than the end I6 and screw-threaded to engage with the corresponding threads I5 of the eye I2. The end of the pin has a turning head I8 for screwing the pin home in the closed position. This type of shackle and pin `has the material advantage that by reason of the threaded engagement of the pin with both the shackle eyes, the pin serves as a strut or a tie to prevent collapse or distention of the shackle jaws. Since, however, the pin has two sets of threads on it it is important to avoid damage to these threads by the dropping ofthe pin.

In order to prevent complete disengagement of the pin I3 from the jaws I0 an abutment I9 is provided on the pin adjacent the threaded portion I6 thereof, and this abutment lies against the inside lface o f one shackle jaw when the pin is screwed home as shown in Figure 1.` The jaw Ill having the eye I2 is slotted at 2U on its interior face to receive the abutment I9 when the shackle` pin is retracted from the closing position, but the slot 20 is not carried through to the outer face of the jaw so that a stop 2I is formed by the base of the slot against which the abutment I9 rests as the pin `is withdrawn so that the shackle pin cannot be disengaged from the shackle. Since, however, the jaws of the shackle must be left clear for the insertion of the part to which the shackle has to be connected the abutment I9 must'be as thin as possible providing that it has the necessary strength to hold the weight of the shackle in the retracted position. Similarly the slot 2B is carried through the shackle arm sufficiently far so that the stop ZI is only strong enough to hold the shackle pin in the retracted position. From this it will be seen, as shown in chain-dotted lines in Figure 1, that when the shackle pin is retracted to open the jaws an almost negligible projection of the end of the pin is present due to the combined thicknesses of the abutment I9 and the stop 2l. The degree of projection of the end of the pin is dependent on the spacing'oi the abutment on the pin and the stop on the shackle (considered axially of the pin) being as nearly equal as possible to the distance between the turning head of the pin and the start of the `thread remote from such turning head. The l width of the abutment iii and of the corresponding slot 2li (seeFigure 2) is maintained at a minimum consistent with the abutment and stop having suicient strength to carry the weight oi the pin, and by this arrangement a full bearing surface between the pin and the shackle eyes is obtained.

Itv will be observed lthat the construction described does not weaken the shackle to any extent but yields thevery material advantage that the v shackle pin when withdrawn to open the jaws cannot become disengaged from the eye-holes and fall out and the threads become damaged when, for example, working at heights above the deck of a ship; similarly if the operator has to hold the shackle attached to one part and another part to be located between the jaws ci the shackle, on turning the shackle round the pin will slide towards the closed position by gravity enabling the manipulator to effect a coupling.

In Figures 3 and l the abutment IQ is formed by channelling the shank of the pin I3 adjacent the threads Il@ with a morticing tool and turning the metal which has been channelled upwardly to form the abutment. Y

In Figures 5 andl 6 the abutment is formed by means of' a small angle iron countersunk at 22 in the shank I3 and spot-welded in position.

In Figures 7 and 8 the abutment is formed by tapping a hole 23 in the shank I3 and inserting a grub screw 24 with a` flattened projecting part 25.

The modification shown in Figure 9 is applied to the common type of shackle having a closure pin with one threaded end I6 engaging a correspondingly threaded eye II, the shank 2E of the pin I3 being plain upto the turning head 27. The Aabutment I@ engages the stop 28 at the end of a slot 253 in the shackle jaw 3U.

In the detailed View comprising Figure l0 the abutment IQ is hinged at 3l to a base plate 32 countersunk and spot-welded in a recess 33 in the pin I3( vA spring 34 biases the ab-utment I9 to its lupright position. This construction of pin and abutmentis used in conjunction with the shackle having slotted jaws shown in Figure 1. In'some classes of work in which shackles are used the shackle pin has to be threaded through a loop in, for example, the end of a rope to be` attached to the pin, and this loop may be substantiallyequal to the diameter of the pin; thus to pass the pin through the loop the abutment must be capable of folding down against its spring 34.

In Figure 11 the threaded end I 6 of the pin I3 incorporates one or more spring-pressed plungers 35 only one of which is shown in Figure 10. This spring-pressed plunger when released from the eye-hole II of the shackle jaw I forms an abutment which will engage in the recess 3S on the inside surface of the eye-hole I2, thereby enabling the whole of the threaded end I6 to be housed within the eye-hole I2, and leaving the space between the jaws IG entirely unobstructed.

In the modification illustrated in Figure l1 the retaining means of the shackle pin is not so positive as the retaining means illustrated in Figures 1 to 10, but the construction may be used where it is essential to have the jaws entirely unobstructed.

In the modification illustrated in Figure 12 the abutment I9 comprises a leaf spring bent to form a retaining pawl, the tail of the spring 37 being spot-welded in the recess adjacent the threads I6.

I claim:

1. A shackle comprising a U-shaped body part, the jaws of which have eye-holes, at least one of which is internally threaded, a closure pin having a turning head and a screw-threaded end remote from the said head, an abutment located on the pin so that it lies against the interior face of one jaw when the pin is in the closed position and a recess on the interior face of the other jaw the base of which recess is adjacent the exterior face of the said jaw and forms a stop for the abutment.

2. A shackle as claimed in claim l, wherein the base of the recess is spaced from the abutment by a distance, along the axis of the pin, which is substantially equal to the distance between the head of the pin and the start of the thread remote from said head.

3. A shackle comprising a bow-shaped body part the arms` of which have eye-holes in alignment with one another, and at least one of the said eye-holes being internally threaded, a closure pin having a turning head and a screwthreaded portion at the end of the pin remote from the said head, a spring-pressed abutment on the pin adjacent the threaded end thereof, and a corresponding recess in the eye-hole adjacent the turning head, when the pin is in the closed position, which recess receives the said springpressed abutment on withdrawal of the pin to restrain the pin from complete separation with the shackle body part.

4. A shackle as claimed in claim 1 and having an abutment-receiving recess open to one eyehole, and a spring-pressed abutment on the pin adapted to engage in the said recess and hold the end of the pin within the eye-hole when the pin is withdrawn to open the shackle.

5. A shackle comprising a U-shaped body part the jaws of which have eye-holes at least one of which is internally threaded, a closure `pin having a turning head, and a screw-threaded end remote from the said head, an abutment located adjacent the screw-threaded end of the pin and angularly movable towards and away from the axis of the pin, a yielding device between the abutment and the pin and biasing the abutment to its projecting position, and a stop for the said abutment on the -shackle whereby the -pin when the shackle is opened is restrained from complete withdrawal.

WM. STEVENSON.

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