Abstract: A detachable chain composed of chain links is broadly used as a conveyor chain with attachments for various kinds of articles to be conveyed, or as a power transmitting chain. The conventional chain of this type, however, could convey only light load when used as a conveyor chain and could run only at a low speed when used as a power transmitting chain. This invention provides a detachable chain improved both in the rupture strength and service life, as well as a method of producing the same.

Abstract: A chain lock for round chain links, particularly for use in mining, consisting of preferably congruent part links, a center portion and a locking pin. The center portion is supported on cylindrical surfaces which form the base of a recess. The recess is provided in either inner side of the inner shank of the part links and undercuts both outer sides of the shank attached to it. The center piece has cylindrical supporting surfaces on opposite sides, and a pair of flat surfaces which are pierced by the cylindrical-surfaced supports. The ends of the center piece are supported in the receiver of the shanks when the center piece is inserted. The pin pierces the center piece at an angle and protrudes with its ends above and below the surfaces of the center piece to prohibit it from being rotated.

Abstract: A rub link assembly for replacement of a link or links of the lower hoist chain on a dragline bucket including a rotating collar affixed to a plastic bushing which allows rolling as contrasted to scraping action against the bucket sides.

Abstract: A hook line includes a hook portion and a link portion contained in two different planes substantially perpendicular to one another. A projection tip is provided on a distal end of the hook portion to provide secure locking action between adjacent hook links; the normal clearance between the tip and the connected link portion being insufficient to allow coupling/uncoupling action. A tip receiving groove extends substantially laterally across the elongated ring forming the link portion. The ring defines a longitudinal slot for receipt of said hook portion. The groove of one hook link receives the projection tip of an adjacent hook link to allow coupling/uncoupling action. In the preferred embodiment, the groove extends along an arc between a transverse midline of said longitudinal slot and an end of said longitudinal slot opposite said hook portion. The groove and tip structure substantially eliminates uncoupling during normal conveyor operation even when subjected to incidental slackening.

Abstract: A connector (10) interposed in a support element (L) by attachment to first and second displaced ends (L.sub.1, L.sub.2) thereof to selectively permit an object to pass transversely through the longitudinal axis of the support element while employed to brace a structure including a first linkage (12, 113) connected to the first end (L.sub.1) of the support element, a second linkage (11, 114) connected to the second end (L.sub.2) of the support element, and means for coupling the first and second linkages (14; 111, 112) being attached to said first linkage and the second linkage and having a receiver (16; 111, 112) selectively opening to either side of the support element to permit an object to pass transversely through the longitudinal axis of the support element.

Abstract: A fastener hook for joining a flexible line to any target object capable of being engaged by a hook, and consisting of a generally planar, rigid body having a generally spiral slot of more than 360 degrees angular extent formed therein, the slot opening through an edge of the body to be engageable over the target object and closed at its opposite end, and an elongated connector joined at one end to the body member within the confines of the spiral slot for rotation about an axis normal to the body, and being connectable at its opposite end to the flexible line.

Abstract: A gripper conveyor assembly includes a plurality of grippers. A conveyor chain moves the grippers along a track from a pick up station to a receiving station. The conveyor chain has identical links. Any one link can be removed from the chain while all of the other links remain interconnected and enclosed by the track. Each of the links includes a body section with rollers which engage the track to guide movement of the body section along the track. Plug and socket type universal joints interconnect the body sections of the links. An opening having a length corresponding to the length of the body section of a link is provided in the track. When a link is rotated, through approximately 90.degree. at the opening, the plug and socket joints can be disconnected and the rotated link removed from the conveyor chain.

Abstract: A self-locking link includes two identical link elements which are adapted for connection to two chain links and for mutual engagement with each other. Each link element is generally L-shaped and includes a head portion and a body having an aperture therein. Each body aperture includes an enlarged portion as well as a narrower, elongated portion aligned with a straight line extending between the two chain links to be coupled. The enlarged portion of each aperture is adapted to receive the head portion of the other link element and includes a V-shaped notch therein extending along the aforementioned straight line between the two coupled chain links. Application of a work force along the thus connected link elements of the generally rectangular shaped self-locking link results in the displacement of the head portion of each link element into the elongated portion of the aperture of the other link element.

Abstract: A bracelet comprises a plurality of interengaging pivotally-connected flat links. Each link has an elliptical contour and a central diamond-shaped opening, a first channel in the upper face and a second channel in the lower face, the channels crossing each other so that the sides of the channels coincide with the pairs of opposed edges of the opening. One end of the first channel has a slot extending from the edge to the opening for the passage of another link during assembly. This other link is turned through 90.degree. to lie in the same plane after passing through the slot and the links are pivotally connected by pivot pins which pass through apexes of the diamond-shaped opening lying on the center line of the bracelet and are received in holes extending within the thickness of the links.

Abstract: A semi-submersible drilling rig or the like having a plurality of chain lockers, a plurality of anchor windlass assemblies and a plurality of fairlead assemblies, a plurality of lengths of chain each having a multiplicity of interconnected links configured to move from a chain locker in cooperative relation through an associated anchor windlass assembly and an associated fairlead assembly, an anchor for each length of chain, and a connector connecting each anchor to the end of the associated length of chain outboard of the associated fairlead assembly so as to engage with the water bottom. The invention further comprises providing in each length of chain at least one link normally disposed within the chain locker inboard of the associated anchor windlass and fairlead assemblies, each of which includes a plurality of removably interconnected parts operable when interconnected to interengage with the adjacent links of the associated length of chain.

Abstract: A connecting chain link with two loops for accommodating chain links of attached chain lengths comprises two main link parts identical in shape and dimensions and assembled along a first contact surface and a second contact surface which is complementary to the first one, and a limiting surface in the central portion of the link. The contact surfaces extend between an origin at the outer periphery of the link and close to a transverse axis thereof, and a termination at the inner periphery of one of the loops. The contact surfaces consist of a plurality of differently oriented surface sections and are so shaped as to form a plurality of intermeshing lug and recess means which effectively oppose tension stresses in the longitudinal direction and all stresses in the transverse directions, the latter ones particularly efficiently at the locations of said origins.

Abstract: A connecting link utilized in a pendant line for connecting lengths or segments of wire ropes used in anchoring offshore drilling barges and the like to facilitate the handling of the pendant line when it is being placed into service, removed from service and during storage by positively and securely but yet detachably connecting adjacent ends of adjacent segments in order to enable a pendant line of desired overall length to be utilized but yet easily handled when the pendant line is being assembled and placed into service or disassembled and stored on a reel when being removed from service.

Abstract: A detachably interconnectable chain link and a chain comprising a plurality of the links in interconnected relation. The links are preferably of substantially figure 8-shaped configuration and comprise slightly resilient first and second substantially S-shaped link elements secured to each other in crossing relation so that they cooperate to define first and second substantially closed loops at the opposite extremities of the link with the adjacent terminal ends of the link elements in closely adjacent, but disconnected laterally offset relation. The links are interconnectable to form the chain by forcing the terminal ends of one link into interlocking engagement with the terminal ends of an adjacent link.

Abstract: A coupling link for chains made of generally round stock has parallel legs and curved end pieces joining the two legs together. A stud inserted between the parallel legs and a locking rod inserted into a hole in the stud and the ring member locks the assembly together. The ring member is made up of two halves that are complementary in outline with each having a curved end piece which forms a short and a long leg. The short leg has a pin thereon and the long leg has a hollow therein for receiving the pin of the short leg of the other link half. The stud and the legs of the coupling member having projecting locking faces for locking the stud in position. The stud is rounded in form at its ends like the chain stock. The stud and the pin are symmetrically placed in relation to the transverse plane of the coupling link. The legs have end faces in the transverse plane of the coupling links inner bearing faces which contact the end faces of the stud.

Abstract: Pin or clip chain for web tensioning machines, including a pin or clip chain link, a connection chain link, a connection pin holding the links together, the pin or clip chain link having a C-shaped box section with a side disposed in a given plane having an opening formed therein and longitudinal ends, and a bearing half shell being disposed in each of the longitudinal ends of the C-shaped box section, the bearing half shells having axes extended perpendicular to the plane of the side of the C-shaped box section, the connection pin being insertable in the opening formed in the C-shaped box section.

Abstract: This invention relates to a coupling link comprising a first half line and a second half link, each comprising a unitary member with a pair of spaced ears at one end, a tongue at the other end and a central body member which joins the ears and the tongue. Bores in each of the ears of the first and second half links are aligned with a bore formed in the tongue of the opposite half link when the first and second half links are mated to form a coupling link. A link pin is received in the bores formed in the pairs of ears of the two links and in the bore in the tongue of theopposite link. Each link pin is retained in place by a pair of pin keepers each received in a slot formed in one of the ears to close the pin bore in that ear. Each pin keeper includes a tang which projects from one of the slot openings in the ear and is bent out of alignment with the slot opening to retain the keeper within the slot.

Abstract: A semi-submersible drilling rig having a plurality of chain lockers, a plurality of anchor windlass assemblies and a plurality of fairlead assemblies, a plurality of lengths of chain each having a multiplicity of interconnected links configured to move from a chain locker in cooperative relation through an associated anchor windless assembly and an associated fairlead assembly and an anchor for each length of chain connected to the end of the associated length of chain outboard of the associated fairlead assembly so as to engage with the water bottom. Each length of chain has at least one frangible link normally disposed within the associated chain locker inboard of the associated anchor windlass and fairlead assemblies of a different construction with respect to the remaining links of the associated length of chain.

Abstract: In a chain joint which consists of two identical, essentially U-shaped joint halves (1,2), the outer legs (3) and the inner legs (4) of the joint halves are provided with holding teeth (14-16 and 17-19 respectively). The holding teeth are here designed with unequal thickness, in such a way that certain pairs of holding teeth (15, 18) absorb a greater load than the other pairs of holding teeth (14,19,16,17). Due to the chosen arrangement, those zones of the outer legs (3) which are located most closely to the shackle base (9) of the joint halves (1,2) are noticeably relieved, and a premature rupture of the chain joint is prevented in this way.

Abstract: A link component is adapted for interfitment with like link components to form a flexible chain free of hinge pins and cooperable with a drive sprocket. The link component has complementarily-shaped end parts (10, 11; 10' 11') whereof each is the true or inverted image of the other. Each end part comprises a transverse recess (20) located between transverse walls (21, 22) of which the longitudinally outer wall (22) is shorter than the inner wall (21). The shorter end of the outer wall (22) and the recess (20) have complementary rounded formations so that when the end part of one link (10 or 10') interengages with the end part (11 or 11') of an adjacent link, the respective outer walls (22) locate in the corresponding recess (20). Parallel side braces (12, 12') space the end parts (10, 11; 10' 11') apart through integration therewith and have external surfaces spaced laterally beyond the width of the end parts.

Abstract: A chain link, comprising a rod of substantially circular cross-section formed into a generally Omega shape. The link includes a transverse bight portion, a pair of side portions offset below the bight portion, a pair of curved leg portions, and a pair of foot portions splaying transversely outward from the ends of the leg portions.

Abstract: A transmission or conveyor chain composed of a plurality of interconnected identical links which are attachable and detachable without need for pivot pins or other separate connecting hardware. Each link is preferably molded as a unitary structure of plastic material.

Abstract: A joining shackle or link is provided for joining link chain sections and comprises a link shaped assemblage of members including a detachable member or members enabling the joining link to be fitted on the chain sections. Opposed U-shaped parts (1,2) of the assemblage have abutting flanges (3) provided with wedge surfaces (4)and the assemblage is held together by couplers (5) which preload the wedge surfaces and the flanges. This preloading of the joining shackle enables the shackle to better withstand cyclic loading. Two separate U-members (1,2) are preferably present and provide opposed pairs of abutting flanges (3), and the couplers comprise half shells (6) fitting over mid-portions of the U-members and drawable together by screws (8) for preloading of the flanges.

Abstract: A chain coupler link or a chain lock made preferably of round steel is assembled of two complementary J- or U-shaped link halves each having two arms of different lengths. The ends of respective arms are formed with interlockable tongue-and-groove joints and the facing wall portions of the longer arms are formed with arresting grooves directed transversely to the center plane of symmetry of the link. An arresting nose piece is insertable between the wall portions so that the projecting noses engage with respective arresting recesses. A sloping bore passes through the link halves and through the arresting piece to receive a safety pin. To ensure an unobstructed insertion of the safety pin into the sloping bore, the noses and the corresponding arresting recesses have different cross sections, so that the arresting pin is insertable between the link halves in a single orientation only.

Abstract: An improved connector for coupling a chain to a wire rope or cable such that the resulting connection can be passed over a sheave, pulley, wheel or windlass without excessive stress applied to the wire rope. A housing is provided having an axially symmetric opening through the housing with an exterior surface adapted to rest upon the outer peripherial portion of the windlass (or the like) as the connection traverses the windlass and wherein a retaining pin perpendicular to the axis of the opening at essentially the center of the housing holds a pair of rotatable U-shaped members within the housing for connecting the chain to the wire rope. Such a connection is particularly useful in coupling an anchor chain to a wire rope in anchoring systems.

Abstract: A universal or ball pivot-link chain arrangement has chain link elements subdivided in an axial plane, each chain link element has a ball pivot body provided with an undercut portion of substantially hemispherical shape. A ball socket enclosing the ball pivot body of an adjacent link has a ring connection at the region of said undercut portion of the adjacent link. Each ring connection has ring-shaped braces engaging countersurfaces of the ball socket. These braces are effective not only in the radial direction, but are arranged to act as blocking devices against any relative displacement of the two halves of the chain link elements in the axial direction.

Abstract: At the nodal points of the chain net in a tire chain, components (1) are provided which have at least one T-shaped section, the transverse bar (3,4) of which forms holding arms (5) for chain links (6) to be hung in; in these components, the ends, forming locking pins (9), of a closure element (8) mounted in a bore (7) in the middle of the longitudinal bar of the T-shaped section serve to secure the chain links (6) hung into the hook-shaped holding arms (5) (FIG. 1).

Abstract: A quick-coupling link to be utilized in conjunction with an identical link has a slot in one of the longitudinal side portions of the link. A tab extends from the opposite longitudinal side portion to adjacent the slot. The tab spans the width of the slot. When a pair of identical links are joined, the tabs prevent the links from accidentally being uncoupled as the slots cannot be brought into disengaging alignment without bending the flexible tab away from the entry to the slot.

Abstract: A optimized two-piece master track link for connecting together the ends of an articulated track is described. The two link parts forming the track link interface together along a generally flat diagonal surface defined by each of the two link parts. Each of the two diagonal flat surfaces has a mutually facing cavity. Each cavity has an interior side wall which faces away from the diagonal surfaces. A complementary dowel pin fits within the hollow space defined by the two cavities and resists separation of the two link parts along three mutually perpendicular directions. Shoe bolts extend from the outside of the track shoe to one of the link parts through the other link part so that both of the link parts are joined to the track shoe. One end of each of the two diagonal flat surfaces is immediately adjacent the track shoe. The opposite end is spaced at an intermediate position between the inner and outer surfaces of the track link.

Abstract: The specification discloses a chain link assembly and chain incorporating said assembly, the chain being especially adapted for use in enclosed track-type conveyors. The assembly includes a pair of identical, elongated link members fitted together and mating with one another. Each link member has chain pin or fastener receiving openings at either end and a bridge member adapted to engage, support, and space the opposite link member. One end of each link member at the same end of the assembly includes a curved surface with elongated chain pin receiving openings to allow articulation of the assembly at that one end. The opposite ends are planar.

Abstract: The specification discloses a chain link assembly and chain incorporating same especially adapted for enclosed track-type conveyors. The assembly includes elongated link members each with chain pivot pin or fastener receiving openings at either end and spaced, rigid bridge means at two positions intermediate the ends and pin openings for spacing and supporting the link members. Preferably the bridge members include means for supporting a chain wheel support while the link member ends include curved surfaces with openings which are elongated to allow articulation of the assembly with respect to other link members in a chain. In one form, the link members are identical, each including one bridge member having an indexing tab received in the opposite link member to align the openings and keep the link members in registry.

Abstract: A multiple link transmission chain composed of interconnected identical links, having identical ends which are angularly disposed with respect to each other by 90 degrees in relation to the longitudinal axis.

Abstract: The barrels of the links of pintle chain for operation open end forward over a drive sprocket are extended inwardly respecting the tooth pockets of the sprocket and two, flat separately distinct areas of interengagement are provided. The two areas of interengagement include the bottom face of the barrel and the bottom face of the tooth pocket and the forward tooth face and rear barrel face. The intermediate corners of the tooth pockets and of the barrel are rounded only for practical purposes.

Abstract: The invention provides an improved connector pin for use in connecting adjacent links of a bracelet, particularly a link watch band, together in releasable yet secure fashion so that one or more links can be readily removed with a simple cylindrical tool to adjust the length of the bracelet to the wrist size of the wearer.

Abstract: The center link of a trolley conveyor chain of thermoplastic construction is provided with a bushing insert for the pin which is pivotable on oppositely projecting studs of the center link. The studs also prevent the free movement of the pin in the slot and serve as detents to prevent the unintended disassembly of the chain.

Abstract: A tire protector for reducing wear on the tires of heavy vehicles consisting of two or more parallel rows of spaced apart chain links. These links are joined by couplings members and consist of metal bars or wires which are bent so that they encircle each two chain links and that the ends of the bars or wires overlap side by side. These overlapping ends are positioned to face upwardly and flat when the protector is mounted to a tire. As a result only a relatively small area comes continually with contact with the ground and is thus exposed to wear and tear. This contacting area is strongly enforced due to the thickness of the sidewise overlapping ends, as a result, parts of the protector, such as the chain links and the bars or wires which form the coupling member, can be made fairly thin as they are not exposed to considerable wear thereby reducing the overall cost of producing the protector and also extending its lifetime.

Abstract: The disclosure embraces a mooring system of the type used to anchor floating bodies with a vessel having a plurality of rollers for taking up and laying sections of cable which are joined together by an improved hinge link; at one end, the cable is secured to a floating body, at an intermediate portion to an anchor and, at its other end, when the system is installed, to the body that is to be moored; the sections of mooring cable are joined together by a hinge link having two U-shaped half-links where the free ends of the U-shaped half-links are formed with fingers having through bores which interfit with the fingers on the other half-link; a retaining pin is provided with a head and shank portion which fits through the bores of the fingers; the head of the pin has a flat side to prevent the pin from rolling when placed on a surface; the shank of the pin is provided with a bore intermediate its ends for receiving a cotter pin and the midpoint of the shank of the pin is provided with flat sections to permit gr

Abstract: A tire chain with a plurality of vertical links connected to each other by means of connecting elements, each comprising an essentially double-T-shaped basic body provided with at least one projection between its cross-bars, which projection is offset by 90.degree. to the cross-bars and projecting into the inner space of at least one vertical link hingedly connected by the connecting element with at least two further vertical links, the links connected together all surrounding the longitudinal bar of the basic body with their U-shaped bow portions.

Abstract: A chain link bracelet of the cross-weave or polynese type is lengthened or shortened by adding or removing a chain link assembly which consists of a pair of flattened helices which are coupled permanently in mesh by a captive hinge pin. The assembly is coupled to the bracelet by means of a releasable headed pin which passes through the intercalating convolutions of the link assembly and the bracelet.

Abstract: A chain has alternately arranged center links and sidebars that are interconnected by pins of a predetermined diameter. An elongated opening is provided in each center link for receiving two pins. Adjacent each end of the elongated opening, lugs project from the center link to restrict the opening opposite the lug to a transverse dimension less than the pin diameter. Each lug is spaced from an adjacent opening end by a distance enabling one pin to fit between the adjacent opening end and the lug. Each pin has a transverse groove for receiving one of the lugs when the pin is in a predetermined rotational angular relationship with the center link. Thus, the pins can be moved past the lugs, in directions to and from the adjacent ends of the elongated openings, when the pins are in the predetermined rotational angular relationship for assembly or disassembly of the chain. The lugs prevent collapsing of the chain when the predetermined rotational angular relationship is not maintained.

Abstract: A coupling or chain connector device is disclosed comprising a first coupling member cooperable with a second coupling member. The second coupling member has a tortuous path between the inner and the outer regions thereof. The tortuous path comprises a first through fourth substantially linear sections and a first through third interconnecting sections sequentially interposed between the first through fourth linear sections. The first coupling member is at least partially receivable in the second coupling member for passing the first coupling member through the tortuous path to couple the first coupling member to the second coupling member. The first coupling member may take the form of a linear wire or bar or may take the form of a substantially ring-shaped structure. The first and second coupling members may be incorporated into a unitary structure with the first coupling member established on one end thereof and the second coupling member established on the other end thereof.

Abstract: A locking element for connecting two chain links is comprised of two elongated locking members each having a recess and two end portions spaced from one another. The locking members can engage one another in which position the one end portion of the one locking member engages the other end portion of the other locking member and vice versa, in one and another planes. The recesses of the locking members together form an inner circumferentially closed recess in which the chain links can move. The locking members can be disengaged from one another, in which position the chain links can be withdrawn from the inner recess. The above planes are offset relative to one another so that during movement of the locking members between the above two positions the chain links received in the respective recesses are moved in planes parallel to the above planes of the engagement of the end portions of the locking members.

Abstract: A locking assembly to interconnect two adjacent members having axially aligned apertures includes a body member having a bore therethrough, a hinge pin with a locking groove therein passed through both the aligned apertures and the bore of said body, and retaining means positioned in said body and adapted to be received in the locking groove to hold the hinge pin in a preselected axial position. In one form, the retaining means consists of a locking pin driven into a blind end bore partially intersecting said longitudinal bore, the portion of said locking pin passing through said longitudinal bore being received in said locking groove.

Abstract: A coupling link having two half links, each half link comprising a U-shaped member, each of the ends of each of the arms of the U-shaped members having at least one ear. The plurality of ears each have an opening therethrough, the axes of the openings being substantially perpendicular to the arms of the U-shaped members. The plurality of ears are adapted to interact with each other so that the openings through the ears will be coaxial and will be adapted to receive a hardened steel pin which will lock the two halves of the link together. The pin is locked into position within the openings of the ears by means of a spacer which is adapted to fit between the ears and is in the form of a cylindrical spacer split along a diameter. The internal diameter of the spacer is substantially the same as that of the pin.

Abstract: A tire chain having annular links and C-shaped links which are hooked into said annular links wherein one of the ends of the C-shaped link has a cross section which is decreased at the expense of its width thereby defining an introduction slot. The annular link has at least one narrowing whose shape corresponds to the shape of the end of the C-shaped link with the reduced cross section and retaining elements for the C-shaped link are provided in the narrowing. The retention elements are provided in the narrowings to prevent disconnection of the joined links.

Abstract: A connecting link formed of a pair of identical generally C-shaped elongated elements each having an interior pin at a first end and an interior pin-receiving aperture at a second end with the interior of the first end being contoured to mate with the exterior of the second end of another link whereby the elements are first moved transversely of each other to position the second end of each of the elements within the first and second ends of the other of the elements and are thereafter moved longitudinally of each other to engage the pins and apertures to assemble the link.

Abstract: A basic mechanism comprising a pair of members which when connected together form a solid unit. Centrally located and passing through the solid member on an axis is an aperture. Formed within each of the solid members is a circular shaped passageway or opening so that when the two members are connected together to form the solid unit, the openings of the two members cooperate to form the shape of a solid torus. The axis of the torus opening coincides with the axis of the aperture. A third member is located within the openings and is movable in respect thereto. With the members connected together to form the solid unit, the third member is movable between the connected together members thereby locking together the connected together members.

Abstract: A tire chain with separable chain strands the end links of which are connectable at each separation point by use of two connecting elements which can be hooked into each other and which are each safely connected with an end link, wherein each connecting element has a body comprising at least one portion bounding an insertion slot which portion has a cross-section decreased at its free end at the expense of its width and wherein the width of the insertion slot is smaller than the height of each of those portions of the body which bound the insertion slot.

Abstract: There is disclosed an improved coupling device or "link" for interconnecting separate lengths of chain and/or attachments thereto and/or for repairing broken chains and method of producing same; said coupling link comprising two half-link units each of which comprises a laminar assembly of two or more relatively nested and interfittingly configured strap-like members. These members are stamped out in generally U-shaped plan form from sheet or plate stock; the legs thereof then being twisted while the intermediate bow-shaped portions of the members remain flat-wise in the planes of the original stampings. Such half-link units may then be assembled and fabricated from only a minimized number (one or two) of differently configured strap-like members disposed in laminate relationship.

Abstract: A quick-connecting link is disclosed having two identical half-links. Each half-link has two arms. One arm ends in a stepwise section and the other arm ends in a stepwise recess. An insert member is held by parallel pins between the two recessed ends of the assembled half-links. The assembly is held together by an expanded sleeve which extends through the insert member, and which lies between and secures the parallel pins.

Abstract: An elongated chain master link is provided including a removable side link of substantially conventional construction but provided with a transverse opening intermediate the opposite end transverse bores formed therethrough adapted to receive groove master link pin ends therethrough. A retaining clip of elongated panel-like construction is also provided and constructed of spring material such as spring steel. The clip includes opposite end transverse openings formed therethrough and one of the end openings includes communicated large and small width portions while the other opening includes communicated greater and lesser width portions.