Abstract: A tent frame binding device permitting speedy assembling and disassembling is disclosed. A binding body is provided with a plurality of slots angularly separated around it, and a pair of fastening recesses are formed at the side walls of each of the slots, the recesses being open upwardly. At the rear portion of each of the slots, there is formed an engaging step, and a frame member fastening part which is coupled with each of the slots is provided with a supporting shaft, the supporting shaft being coupled with the recesses of the slot. At the rear of the supporting shaft, there is formed an inclined portion which is to be coupled with the inclined engaging step of the slot. Tent frame members are inserted respectively into the holes of the frame member fastening parts, and the frame member fastening parts are assembled into the slots of the binding body.

Abstract: A light weight, portable, gymnastic assembly made for children to climb on is fabricated of tubular members formed of cut-to-length standard plastic tubings and standard plastic fittings. The tubular members are releasably held within the sockets of the fittings by pairs of opposing spring-loaded pins that are carried in opposing holes on the end portions of the tubular members and engage within opposing holes on the end portions of sockets of the fittings when the tubular members are slipped into the sockets. Because of the mechanical connections used, such an assembly provides a flexible overall structure that can be readily modified from time-to-time by an adult to enable a number of separately assembled different types of accessories of interest to children to be mounted on the surface of the assembly or within the interior thereof.

Abstract: A device for erecting walls and/or ceilings includes a support shaped-section evincing approximately cross-sectionally T-shaped webs to which at least one beam for wall- and/or ceiling segments can be detachably affixed, further a clamping lock detachable fastened inside the hollow beam and comprising a central retaining element and two spring-steel, lateral retaining elements mounted symmetrically relative to central retaining element. The retaining elements engage adjacent and undercut channels formed by the webs and are tightened against two adjacent webs of the support shaped-section by a rotationally actuated, transverse tightening system crossing the three retaining elements through mutually flush clearances. At the same time, the tightening system affixes the clamping lock inside the beam.

Abstract: A joint structure for removably attaching a ball member to an end of a bar member to form a truss structure is disclosed having an engagement member attached to the ball member, which engagement member has an exterior portion extending outwardly of the outer surface of the ball member, and an attachment device associated with the end of the bar member which removably engages the exterior portion of the engagement member. The joint structure according to the present invention may be utilized with bar members with or without tension rods extending through the bar member. The ball structure may be a spherical shell made of metal or fiber reinforced plastic which is located within a hollow concrete sphere. The spherical shell is not removed from the interior of the concrete sphere, but, instead, is used to increase the tensile force resistance of the ball member. The spherical shell may be imbedded in the ball member at the time of forming the concrete ball and can be used as a molding core.

Abstract: A rigid intersection connection including three intersecting elongated wood structural members and a rigid connector made from a single sheet metal blank which requires no welding.The rigid connector includes a pair of angular members joined in angular relationship and joined at a common outer edge.The rigid connector more specifically includes structure for engaging two sides of one of the elongated wood structural members and three sides of two of the elongated wood structural members.The disclosure includes a log holder, a table, a bunk bed, and a greenhouse or garden structure as examples of structures which can be readily constructed from the rigid intersection connections.

Abstract: A multiple truss connection in which one or two trusses, such as a right hip truss and a jack truss, or a left hip truss and a jack truss, or two hip trusses are connected to a supporting girder by means of a sheet metal hanger. The sheet metal hanger is constructed from a single sheet metal blank in which no welding is required. The sheet metal hanger includes a seat member, first and second backwall members which are connected to the supporting girder and first and second side members connected to the supported trusses. A flange member integrally connected to the seat provides further connection when a jack truss is supported. The identical sheet metal hanger can also be used in a multiple framing member connection in which the wood members are standard lumber rather than trusses.

Abstract: Construction utilizing composite pultrusion technology incorporates an internal web structure in the elongated members themselves, increasing the strength-to-weight ratio, while providing support for joint notches due to the strategic positioning of the webs. The joints themselves are modified to accommodate the exiting of one or two members from the joint at an oblique angle to provide more construction flexibility to make diagonal braces, for example. The improved techniques are incorporated into a power transmission tower which takes advantage of the electrical qualities inherent in composites to produce a mechanically and electrically strong tower.

Abstract: A symmetrical structural component (FIGS. 1A-1D), which when replicated can be used to create a 2- or 3-dimensional framework. Each end of the component comprises two projections 10 that serve as the primary means for multiple component coupling; two internal recesses 12, perpendicular to the projections, for linear coupling; four perimeter recesses 14 for perpendicular coupling; four perimeter members 16, which form the perimeter recesses and have laterally extended portions 19, for perpendicular coupling; and two notches 18 for perpendicular coupling.

Abstract: A wood rafter to wood corner plate connection in either a gazebo or a building roof having a hip roof. A single element sheet metal connector is provided having a base member connected to the corner plate, wing members connected to and tying the corner plates together, and a seat member bendably connected to the base for attaching a rafter at varying angles from 0.degree. to 90.degree..

Abstract: A connector for a space frame on an automotive vehicle having a plurality of structural members in at least two dimensions includes an inner panel, and an outer panel spaced from the inner panel and substantially parallel thereto. The connector also includes a connector panel attached to the inner and outer panel to form a channel defining one dimension and adapted to receive one of the structural members. The connector further includes at least one extension member attached to either one of the connector panel and the inner panel and the outer panel and extending outwardly therefrom to define a second dimension relative to the first dimension and adapted to be disposed within another one of the structural members to form a joint therebetween.

Abstract: A frame assembly for a display structure formed of a plurality of tubular support members joined end to end. An elastic cord is permanently connected in and winds its way through the tubular support members so that the support members are joinable in only one predefined arrangement to facilitate set up of the frame assembly. Some of the end-to-end connections include key and keyhole connections with apertured keys through which the elastic cord extends.

Abstract: A connector kit for construction of structures from pipe such as PVC pipe. The connectors include a body (2) through which an aperture (8) is provided. Extending from the body are pins (4,6) onto which a pipe (16) is attached by sliding the pipe over the extensions. The aperture in the body is adapted to receive one of two types of pins. The first of the two types of pins (12) is of sufficient length that it will allow slotted ends thereon to extend out of both the top and bottom of the body when inserted. The second type of pin (14) will extend out of only one end of the body when inserted therein. The two pin types allow the use of a single body type for internal and external connections within a structure, but also on top or bottom portions of a structure.

Abstract: A fastening system for making right angle interconnections between first and second rigid structural components of a framework, each having at least two flat mutually parallel sides and each carrying a track. A "U"-shaped connector having a flat base and mutually parallel upright stems is disposed so that the base of the connector engages one of the tracks of the first frame member and the upright stems engage the respective tracks of the second frame member.

Abstract: Improvements are provided in a bunk bed which includes a head board having a pair of spaced-apart legs and upper and lower transverse frames, a tail board having a pair of spaced-apart legs and upper and lower transverse frames and connecting members comprising a pair of transversely-spaced-apart upper and lower longitudinally-extending frames. A first improvement is in the form of an assembly bracket comprising an apertured side plate, an apertured face plate securely-connected thereto, and a perpendicularly-extending ledge extending along the length of the side plate. That ledge also extends from a face of the face plate and is securely-connected both to an intermediate region of the side plate and to an intermediate region of the face plate.

Abstract: A three-way clamp for the assembly of structural frameworks is disclosed. The clamp includes a block-like clamp body provided with a first bore extending through the block and second and third bores intersecting with the first at right angles and intersecting with each other at right angles. The clamp body is slotted in the plane of the axis of the second and third bores, to form cantilever extension portions of the block body capable of being squeezed together by a single compression bolt. Strut-like tubular structural elements are received in the several bores, one passing through the block, the other two being inserted endwise into the second and third bores. By tightening the single compression bolt, the clamp body is caused to be tightened down into secure gripping relation with structural elements in each of three right-angularly related, intersecting axes, significantly expediting assembly, disassembly and adjustment of frame structures.

Abstract: A hub for providing an articulating interconnection between the ends of tent frame struts, comprising a base member and a cap member rotatably interconnected by a common axis of rotation to form an encasement having a plurality of interior cavities equally spaced radially from the common axis, a like plurality of elongated windows each having top and side framing portions and a sill, each in communication with one of the cavities, a like plurality of radial slots in the base member in respective communication with one of the said windows and a like plurality of sockets, each having a spherical terminating end portion and disposed in each of said cavities.

Abstract: An extruded node is disclosed comprising a longitudinally extending substantially hollow core and at least one longitudinally extending, hollow flange, extending outwardly of and integral with a longitudinally extending side portion of the core. This invention also provides a joined structure wherein at least one longitudinally extending lineal member has a hollow peripheral portion defined by walls having inside surfaces adapted to mate with outside surfaces of a mating hollow flange of the extruded node. In this joined structure the peripheral portion of the lineal member is inserted over the hollow flange of the node to an extent that the outer peripheral surface of the lineal member surrounds the integral wall of the node and the outside surfaces of the sidewalls of the hollow flange and the inside surfaces of the lineal member mate along substantially the entire length and around substantially the entire perimeter of the flange.

Abstract: A tent frame folding device is disclosed which is constituted such that a locking cap is provided to the central fastening section in such a manner that the locking cap should be pressed down or lifted up, according as a lever is switched to the vertical or horizontal position, thereby making it possible to lock up or release the unfolded state of the tent only through the manipulation of the lever. According to the present invention, the folding and unfolding of a tent can be carried out in a simple manner, and the unfolded state of a tent can be securely maintained.

Abstract: A light wood truss connection in which a hip truss and a jack truss are joined to a wood supporting girder by means of a sheet metal connector which includes first second and third side wall members and first and second back wall members. A single seat supports the hip truss while the jack truss is supported by fasteners only inserted through the third side wall member. Support for the jack truss is also by fasteners in double shear.

Abstract: A structural system of modular components which promotes rapid erection of building type structures is disclosed. The modular building structure system comprises a plurality of beam members, a plurality of column support members, and a connector means for affixing the beam members into a structural gridwork. Each beam member is positioned between and aligned with two nodes of a planar assemblage of interconnected polygons to form a structural gridwork that is congruent with the planar assemblage of interconnected polygons. The column support members are positioned between two structural gridworks and aligned with two nodes, one node being in each structural gridwork. The column support members include endpieces enabling the column support members to be affixed to the structural gridwork. The connector means comprises a plurality of tubular hubs positioned at the nodes of the structural gridworks and a plurality of radial flange sets.

Abstract: An extruded node is disclosed comprising a longitudinally extending substantially hollow core and at least one longitudinally extending, hollow flange, extending outwardly of and integral with a longitudinally extending side portion of the core. This invention also provides a joined structure wherein at least one longitudinally extending lineal member has a hollow peripheral portion defined by walls having inside surfaces adapted to mate with outside surfaces of a mating hollow flange of the extruded node. In this joined structure the peripheral portion of the lineal member is inserted over the hollow flange of the node to an extent that the outer peripheral surface of the lineal member surrounds the integral wall of the node and the outside surfaces of the sidewalls of the hollow flange and the inside surfaces of the lineal member mate along substantially the entire length and around substantially the entire perimeter of the flange.

Abstract: Support means for foldable structures of the type having a roof of foldable material and a vertical mounting shaft staking perpendicularly to the ground. The interlocking support means consists of upper and lower interlocking members. A plurality of horizontal ribs are pivoted and clamped in the interlocking support means so that the ribs are held horizontally, but can fold down along the vertical shaft for transportation. The ribs have a channel cross-section. A rope extends from the end of one rib through the rib channel, through the interlocking mounting means and then through a second rib, whereby the ends of the rope may be used to stake down the structure and support side walls.

Abstract: This invention involves connectors for vertical end rectangular grids having spaced pairs of vertical end rails joined to horizontal rods extending between the end rails with vertical spaced rails between the end rails. Each connector includes a rigid, flat plate formed with two or more horizontally spaced symmetrical notches. Each notch has a passage extending inwardly from an end edge of the plate. The passage terminates at two inner opposed concave lobes each of of which slidably engages a respective vertical end rail. The passages permit the plate to move beyond the horizontal rods when the plate is moved along the end rails. A third inner lobe between the two opposing lobes allows the plate to pass free projecting ends of plates can have two, three, four or more notches to hold vertical grids in free standing, upright angular arrays. Stop blocks can be placed below the connectors to hold them in desired positions on the rails supported by the horizontal rods projecting through the rails.

Abstract: An assembly of prefabricated structural components for lattices or trusses includes a plurality of rod-like, load-bearing elements, a plurality of joining elements for joining the rod-like elements to one another, a plurality of connecting elements for connecting the rod-like elements to the joining elements, and a plurality of clamping elements for clamping the connecting elements and associated rod-like elements to the joining elements. Each joining element has a spherical peripheral surface provided with first and second T-grooves disposed at opposite ends of a predetermined diameter of the surface and at least one additional T-groove extending circumferentially of the surface in a plane normal to the predetermined diameter. The connecting elements resemble T-bolts and one connecting element is receivable in each first and second groove while several connecting elements are receivable in each additional groove.

Abstract: The invention relates to a connective apparatus between a truss beam and another object, e.g., a second truss beam or another device, for rigidly joining the two together. The connective apparatus comprises a unitary attachment device which is connected to one of the frame elements in a truss beam. The device includes a rabbet member capable of attachment to a pair of struts of the frame element and a connector member attached to the rabbet member. A connector strut is provided for joining two or more truss beams to each other by interconnecting two nodes of the respective beams.

Abstract: A chair structure is disclosed. The chair structure is provided with a chair seat section including first and second transversely spaced legs, a transverse cross brace fixed to and rigidly interconnecting the legs, first and second transversely spaced seat side support members having respective first and second end portions thereon, and a fabric extending between the seat side support members and forming a seat therebetween. The cross brace comprises an elongate member having a decorative outer side, first and second spaced apart end sections and an inner side. The inner side of the cross brace includes a support surface thereon for supporting the end portions of the seat side support members on the end sections of the elongate cross brace member, with the end portions of the seat side support members being substantially shielded from view, in front elevation, by the decorative outer side of the cross brace.

Abstract: A connector for connecting structural members such as panels, rods and tubes, to form a three-dimensional structure, comprises a connector body with a pair of axial slots at opposite ends thereof shaped to receive and retain tongues on the ends of the structural members and at least one annular channel extending around the connector body to receive similar tongues of further structural members extending in directions transverse to those in the axial slots. The axial slots and the channel have constrictions adjacent the outer surface of the connector body to retain tongues having widened free ends which are elongate in end view.

Abstract: A connector, for releasably securing and supporting as many as three elongate elements such as tubing, piping and the like along mutually perpendicular axes. The connector comprises a first U-shaped member, having parallel spaced arms extending from a base, with aligned openings in the arms spaced from the base. The openings are shaped and sized to receive one of the elongate elements therethrough. A second elongate element may be inserted into the space between the arms of the U, the base portion of the U and the first elongate element, perpendicularly to the latter. A lock mechanism on the U-shaped member is provided to secure the elements in frictional engagement. A second U-shaped member having parallel spaced arms connected by a base has its base attached to the base of the first U-shaped member. The spaced arms of the second U-shaped member are shaped and dimensioned to engage the end of a third elongate element, which is held in position by a second locking mechanism.

Abstract: In a joint including a plurality of bars linked thereby, the ends of the bars are inserted through apertures in a metal casing which is filled with a hardening grout. The ends of the bars received in the casing have necked-down portions having two tapered members therein which are oriented with their tapering sections facing in opposition and which are pretensioned toward each other by a tensioning member to contact the walls of the necked down portion in flatwise abutting engagement, in opposite sections of the necked down portion.

Abstract: A connector for joining a wood member such as a hip truss and a second wood member such as a jack truss to a third wood member such as a girder truss. The connector is formed with a seat for receiving the bottom edges of the hip and jack truss, side members and tab members which respectively attach to the sides of the hip and jack trusses, and back members which attach to the carrier girder truss. The connector is constructed from a single sheet metal blank member and requires no welding. The hip and jack trusses intersect at an angle less than 90.degree. and attach to the bottom chord of the carrier girder truss.

Abstract: This is a holder for shotgun pattern paper. The shot pattern of a shotgun is most important to a hunter. This invention provides a way to determine that pattern for any shotgun. A three-part circular or four-part square holder is supported above the ground by two spaced apart support members. The parts are held together by unique clamp. Clips are provided about the periphery of the square or circular ring for holding paper or a cardboard target base with the target printed thereon. A shotgun or rifle is then fired at the target from the selected distance and the pattern of the shot or accuracy of the rifle can be seen on the paper or target base.

Abstract: The invention is a photo clamp joint which can display photographs in various flat or three-dimensional displays, the device is composed of two four leaf clover shaped pieces having crossed small semi-circular protrusions to clamp photos or other paper materials in series to form different shapes for the purpose of creating a display.

Abstract: A fixing bracket 5 in a roof construction is a metal sheet with two parallel grooves 39, 40 pressed therein to protrude as ribs from the other side of the sheet. each groove extending from one edge of the sheet to another with two straight end portions and a central part-circular central portion. The outer edge of the sheet is concentrically part-circular and the inner edge is folded up at 38. Such a bracket, or a pair of such brackets back-to-back with grooves 39, 40 protruding, can connect cold-rolled channels 1,2 e.g. as used for the uprights or rafters of a portal frame structure, with compatible longitudinal base grooves. The channels are again usually used in back-to-back pairs and the brackets are bolted within these back-to-back pairs of channels. The included angle can be from 90.degree.-135.degree. for eaves brackets, or from 90.degree.-180.degree. for ridge brackets.

Abstract: A body member comprising either a concrete block or molded or stamped product, includes upwardly opening recesses forming an anchor seat for building elements. The recesses may extend fully from side to side and also open out the sides so that building elements can be laid horizontally therein or fully across the body member. The recesses also include a central socket for receiving an upright pillar. Embodiments of the invention may include depending foot members. Embodiments of the inventions also include structure for fastening building elements to the body member. A further embodiment employs depending projections at outer portions thereof which frictionally fit on top of a base block and stabilize the body member against lateral movement.

Abstract: A fastener for joining together a plurality of panel members at their corners provides tight, aligned joinder between the panels, yet can be rapidly disconnected to facilitate the transportation of the panels. The fastener includes a central hub portion against which the corner portions of the panels to be joined together abut in mating relationship; the corner portions of such panels being preformed to the shape of the fastener central portion to enable such mating engagement. Extending from one end of the central portion is an overlapping member which fits flush against one surface of the panels to be joined while extending from the opposite end of the central portion is a second member which is in opposing relationship to the opposite surface of such panels. Clamping members attached to the second member have arms which extend towards each other at convergent angles.

Abstract: A device comprising a frame composed of lengths of tubing and coupling pieces interconnecting the same, coupling piece and coupling piece parts for the same, each coupling piece having a cubical body provided on each outer face with a recess with undercut engaging rims for receiving a base part of an arm connected with a tubing and having complementary engaging rims in a manner such that the arm is fixed in place at least in the direction transverse of the outer face. The edge of the body is equal to the thickness of the tubings, the body consists of two identical parts having a square head face, each part having complementary connecting means for joining a body part by a base face to the base face of the other body part in a direction transverse of the head face, while each side face has a recess which is accessible only from the base face for the base part of the arm and which forms, together with a corresponding recess in the other body part, the recess for receiving the base part of an arm.

Abstract: A joint is provided by means of which structural elements, such as steel bars or pipes can be connected with one another to form spatial structures, say the skeletons of roof constructions. The joint consists of a hollow cylinder or prism in the wall or walls of which are apertures into which the said structural elements are inserted.

Abstract: The present invention pertains to the technical field of network structures and more particularly it relates to a knot joint of the kind adapted to engage a number of rods converging in the joint itself.According to the invention the joint (1) comprises a central core (2) and first and second couplings in alignment with said rods (3) and connected to said core (2) and said rods (3) respectively, as well as suitable to be engaged with each other by a restrained fixing, said first and second couplings consisting of clamps (8) and inserts (9), the shape of which mates with that of said clamps (8), insertable into the latter by causing them to slide in a sense transverse to the extension direction of said rods (3).

Abstract: A corner connector assembly for a tent characterized as a two-part casting arranged for a floating relationship, the latter serving advantages in assembling struts or eave bars having crimped areas proximate the ends thereof which cooperate with projections on the inner surfaces of hollow arms forming part of the assembly. The arrangement also includes a vertical adjustment feature for the leg supporting the connector, such involving upper and lower members, the upper member being rotatable within the lower member by means of a bolt riding along a spring, to accommodate for variations in the terrain or other supporting surface.

Abstract: A gridwork for a suspended ceiling is assembled by a clip having three equally angularly disposed prongs which run parallel to three equally angularly disposed elongated rigid members of the gridwork. One prong has a stepped configuration, where each level abuts against a portion of two of the three intersecting members. One level of this stepped configuration widens into a lip fitting into a flanged or a "u" shaped channel area of one of the members, and which widened area further snaps into this one member for its securement therein. The remaining two prongs of the clip are bolted to its corresponding elongated member.

Abstract: This disclosure relates to a clip for securing together adjacent collapsible, expandable, self-locking, self-supporting structures which include a plurality of pairs of crossed rod elements pivotally joined in scissored fashion to each other and to hubs having openings therein, the structures having at least one hub of each section adjacent each other, and the clip having at least two stems with each stem being interlockingly received in an associated opening of the adjacent hubs to thereby secure the structures to each other in any one of a plurality of different configurations.

Abstract: This invention relates to an improved self-adjusting hub and strut-endcap assembly for tent frame roof and wall struts characterized by a two-part hub section sandwiched together in stacked relation to define a set of four sockets, each of which has a channel-shaped entryway which is adapted to receive the socket-forming neck projecting from the ball on the inner end of one of the strut endcaps for limited side-to-side movement therein when in extended position as well as movement between its extended position and a folded position wherein the strut connected thereto lies in nested essentially parallel relation to the other struts of the frame.

Abstract: This is a holder for shotgun pattern paper. The shot pattern of a shotgun is most important to a hunter. This invention provides a way to determine that pattern for any shotgun. A three-part circular or four-part square holder is supported above the ground by two spaced apart support members. The parts are held together by unique clamp. Clips are provided about the periphery of the square or circular ring for holding paper. A shotgun is then fired at the paper from the selected distance and the pattern of the shot can be seen on the paper.

Abstract: A rectangular concrete or like building panel (10) of substantially uniform thickness has connectors (11) inset into its top and bottom corners and securely fixed to metal members (14) embedded within the panel (10). Each connector (11) is a short tube, its ends flush with opposite faces of the panel (10) and with two exposed perpendicular sides substantially level with a side edge and a top or bottom edge of the panel (10), and formed with bolt holes (12) to enable generally similar panels (10) to be secured together by bolts (23) through adjacent connectors (11) and to be bolted to floor (30) and roof structures (41). Intermediate connectors (11a) may be inset and secured into the top and bottom of the panel (10), each with an exposed side flush with the panel's top or bottom edge and formed with a bolt hole (12).

Abstract: A space frame connector which has two inner shells and two outer shells. Each outer shell is fixed to an inner shell with ends of structural members secured between the two shells. The four shells are fixed together with ends of structural members secured between the two inner shells, one being made of a first washer which is engaged with the two inner shells and a second washer which is engaged with the two outer shells.

Abstract: This invention relates to a honeycomb structure reinforced with geodesic structure. The honeycomb structure includes a plurality of elongated structural members with cross sections having a large moment of inertia, which are assembled into a hexagonal network. Each hexagonal subassembly included in the hexagonal network is reinforced by a first set of reinforcing elongated structural members disposed in a triangular pattern wherein three corners of the first reinforcing triangular subassembly disposed flush to one face of the hexagonal subassembly are respectively connected to one set of three alternate corners of the hexagonal subassembly and further reinforced by a second set of reinforcing elongated structural members disposed in a triangular pattern wherein three corners of the second reinforcing triangular subassembly disposed flush to the other face of the hexagonal subassembly are respectively connected to the other set of three alternate corners of the hexagonal subassembly.

Abstract: A tubular reinforcing member having end surfaces which conform to the cylindrical inner surface of a tubular chord member are positioned within the tubular chord member at the intersection of a bracing member. The longitudinal axis of the tubular reinforcing member is positioned so as to be coincident with the longitudinal axis of the intersecting bracing member. The use of the internal tubular reinforcing member constitutes an improvement over the commonly used stiffening rings in the direct translation of tensional and compression forces acting along a bracing member is transferred to a portion of the wall of the chord member opposite to that to which the bracing member is attached.

Abstract: One or more panels of similar construction are formed having a frame on a pair of planar decorative faces are secured. The frame is provided with a centrally located groove in its peripheral edges. One or more connecting bars are provided each having plate-like projections fitting into the grooves. The frames and bars are provided with cooperatively engaging means for removably interlocking the panels and the bars together.

Abstract: A special structure comprising equidistantly positioned knuckles, a set of sections, and means for joining either end of said sections to said knuckles, where each knuckle is made up from two hollow base pieces whose outside shape is approximately that of a spherical shell in which there is a number of equidistantly positioned holes at an angular distance of a width respect to one another. At least one of the base pieces has a perimeter area which is bent inwards. An arrangement for the attachment of the first base piece is provided. When the base pieces are joined together all equidistantly positioned holes lie at an angular distance with respect to one another.

Abstract: A master fitting is disclosed adapted to be subdivided into a set of vertex fittings for use in a truss structure which comprises a plurality of frame elements. Interchangeable vertex fittings with accurately aligned surfaces, slots and holes are provided at a low cost. The vertex fittings are adapted to form the frame elements with mating struts, or to form hinge joints for interconnecting groups of frame elements. The invention permits ease of assembly and quick and easy removal and replacement of a strut in the truss structure.