ATTACHMENT MEANS FOR FASTENING TWO PREFERABLY ROD-SHAPED OBJECTS WITH RESPECT TO EACH OTHER

Abstract: An attachment means for clamping two preferably rod-shaped sections (1A, 1B) to each other, so that the sections are secured with respect to each other partly against displacement in the longitudinal direction of the sections (1A, 1B), partly in an optional angular position with respect to each other. The attachment means consists of two wedge-shaped clamping members (6A, 6B), which by means of a through screw (4) and a nut (5) are tightened towards each other thereby exerting a wedging influence on two objects (1A, 1B) to be connected with each other. Resulting wedging forces are taken up as a traction force within two, preferably hook-shaped attachment members (3A, 3B), which are supported by the screw (4) and are retainingly engaged with the objects (1A, 1B) to be connected with each other. Rigid, resilient gaskets (7) are arranged between the clamping members (6A, 6B) and on opposite sides of the attachment members (3A, 3B) which overlap each other. When the clamping members are tightened together the resilient gaskets (7) exert a clamping force on the attachment members under the influence of which said attachment members are secured in angular position with respect to each other. The clamping members (6A, 6B) preferably consist of frustoconical solids of revolution made of rigid plastic material.

Description: TITLE OF INVENTION: ATTACHMENT MEANS FOR FASTENING TWO PREFERABLY ROD-SHAPED OBJECTS WITH RESPECT TO EACH OTHER The present invention relates to an attachment means for fastening two preferably rod-shaped objects to each other, e.g. rod-like hollow sections or grooved sections, so that the sections are secured with respect to each other partly against longitudinal displacement with respect to each other and partly in optional angular position. The attachment means according to the invention is particularly adapted for use in interconnecting extruded rod-like sections of light metal or plastics, provided with longitudinal T-shaped grooves and intended for use as con¬ structional members in advanced construction-kits for mak¬ ing three-dimensional full-scale models. The attachment means according to the invention may advantageously be used for interconnecting rod-shaped sections of the kind used e.g. in scaffolds, shelf stands etc. According to a previously known system for intercon¬ necting extruded hollow sections having a square cross sec¬ tion including trapezoidal protrusions on the sides of the square which form longitudinal grooves at the corners of the square, use has been made of attachment means consist¬ ing partly of an attachment member which is introduced into the section from the end therof and secured therein, and which i provided with a protecting connecting lug, and partly of separate connecting lugs which may be introduced into two neighbouring grooves to be clamped into abutment against the lug of the attachment member inserted into the section from the end thereof. A disadvantage of said attachment means is that they comprise several separate parts, of which at least one initially must be secured to the section, said parts r then being secured to each other by means of other attach¬ ment parts. Another disadvantage is that one of the attach¬ ment members must be introduced into the section from the end thereof and be secured therein, which leads to li ita- 5. tions with respect to the use of the attachment means. The previously known attachment means discussed above further presupposes sections which are provided with grooves in a very special way and can not be used together with sections having a different shape. 0 For interconnecting tubular sections for scaffolds, shelf stands etc. it is previously known to use attachment means consisting of divided tubular casings in the form of angel-joint pieces or pieces in T-shape, into which the tubes to be interconnected are inserted, said cases then 5 being clamped together by means of screws for fixing to¬ gether the tubular sections. Said attachment means provide relatively limited possibilities of use and must be manu¬ factured in several different variations in order to cover existing needs, e.g. angel-joint pieces, T-pieces, straight 0 pieces etc. The object of the present invention is to provide an attachment means of the kind mentioned initially which renders possible the attachment of two preferably rod- shaped objects to each other, at the same time fixing said 5 objects in the transversal direction as well as in the longitudinal direction and in optional angular position by tightening the tightening members of the attachment means. Still another object of the invention is to provide an attachment means αf a simple design which is easy to use 0 and which, in spite of the fact the it includes several pieces, may be held available as an assembled unit and which does not require any special shape of the cross sec¬ tion of the objects to be interconnected, but which may be used in connection with grooved hollow sections, smooth 5 sections, solid sections as well as in connection with square sections etc. Still another object of the invention is to provide an attachment means which in use provides a firm and safe joint, at the same time giving the joint a sufficient elasticity to restrain vibrations. According to the invention the objects referred to above are obtained by a design in accordance with the specific features specified in the appended claims. The invention is described in the following with re¬ ference to a number of embodiments disclosing some different design variations of the attachment means according to the invention and use of the attachment means for interconnect¬ ing objects of different types having cross sections of different shapes. The embodiments are illustrated on the appended draw- ings, on which Fig 1 is a cross section through two extruded grooved sections which are interconnected by using the attachment means according to the invention, Fig 2 is a horizontal section taken as indicated at I - I in Fig 1, Fig 3 is an exploded view illustrating the different members of the attachment means according to the invention in a first embodiment, Fig 4 is a cross section through a preferred embodi- ent of the attachment means for interconnecting extruded grooved sections Fig 5 is a horizontal section taken as indicated at II - II in Fig 4, Fig 6 is an exploded view illustrating a preferred embodiment of the attachment means according to the inven¬ tion, Fig 7 is a cross section through two simple tubular sections interconnected by using the attanchment means according to the invention, Fig 8 is a horizontal section taken as marked at III - III in Fig 7, Fig 9 illustrates an alternative embodiment for inter¬ connecting two smooth tubular sections by using the attach¬ ment means according to the invention, and Fig 10 illustrates still another embodiment according to the invention. Fig 1 - 6 illustrate in two embodiments, the use of the attachment means according to the invention for inter¬ connecting extruded, rod-shaped sections 1A, IB of light metal or plastics, which are provided with longitudinal T-shaped grooves 2 and which are intended to be used as constructional members in construction kits etc. As attach¬ ment members to be engaged into the T-shaped grooves 2 are used two plate washers 3A and 3B, the extreme end portions of which being bent into hook-form, said washers being in¬ tended to overlap each other and to be clamped together by means of a screw 4 extending through the washers and a nut 5. Clamping the washers- 3A, 3B against each other is achieved by means of two frusto-conical clamping members 6A and 6B, and two rigid, but elastic gaskets 7 disposed on opposit sides of the attaching members 3A, 3B, the clamping action being achieved by tightening nut 5 on screw 4. During the tighten¬ ing operation the conical surfaces of the clamping members 5A, 6B are brought into contact with the sections 1A and IB thereby exerting a wedging action on the sections, ending to separate them from each, other. This is however prevented by the attachment members i.e. plate washers 3A, 3B, the hook-shaped end portions of which being engaged into the respective groove 2. This results in a tensional force by means of which the sections 1A and IB are fixed in the axial direction with respect to each other. When the nut 5 is be¬ ing tightened the plate washers 3A, 3B are also pressed against each other due to compression of the rigid, elastic gaskets 7. This results in that plate washers 3A, 3B are fixed in the adjusted angular position with respect to each OMPI other due to friction. The surfaces of the attachment members, i.e. the plate washers 3A, 3B, which bear against each other may be provided with radially extending grooves or protrutions respectively, which cooperate to retain an adjusted angular position. By turning the plate washer 180° so that the smooth surfaces of the washers are brought in¬ to contact with each other it is thus possible to chose between the use of a stepwise eligible angular adjustment or a steepless angular adjustment only based on friction. In the embodiment illustrated in Fig 2 the attachment means according to the invention is shown in a position in the vicinity of the two ends of two sections 1A, IB, but the attachment means may of course be positioned anywhere along the T-shaped groove 2 of the sections, e.g. when the sections 1A and IB are running in parallel with each other or forming a small angel with each other. The opening of the grooves 2 is dimensioned so with respect to the thick¬ ness of the attachment members 3A, 3B that said members may be introduced through the slot thus formed and not need to be inserted from the end of the section. Fig 3 shows an exploded view of the attachment means. As clearly appears from this figure the attachment means comprises a screw 4 and a nut 5. The attachment means further comprises two clamping members 6A and 6B made of rigid material, e.g. metal, but which preferably consist of a rigid plastic material. The clamping members have a frusto-conical form and are directed against each other by means of the conically tapering ends and are provided with a through hole for the screw 4. Next to the surfaces of the attaching mem- bers which are, facing each other are arranged two preferably circular, elastic gaskets 7 of a rigid elastic material, e.g. rubber. The gaskets 7 have also been provided with holes for the screw 4. The attachment members 3A, 3B which are disposed between the rubber gaskets 7 consist of two plate washers which are bent into hook form. As indicated in Fig 3, two surfaces of the attachment members 3A, 3B which are i-ntended to be into contact with each other may be provided with radially extending rims, which may be ar¬ ranged to have a certain angular graduation between adjac- ent rims in order to render possible a stepwise eligible angular adjustment of the washers with respect to each other. If the washers are turned 180° the smooth surfaces of the attachment members are brought into contact with each other which renders possible a steeplessly eligible angular adjustment. Other means for fixing the angular adjustment may be used, e.g. one or several splines on the screw 4, which are engaged into recesses in the edge of the hole in the members 3A and 3B. The attachment means according to the invention is held available with the clamping members 6A, 6B, the gaskets 7 and the attachment members 3A, 3B mounted in the order mentioned onto the screw 4 and with the nut 5 screwed theron. When the attach¬ ment means shall be mounted the nut 5 is disco.nnected and clamping member 6A and rubber gasket 7 and possibly also one or both of the attachment members 3A and 3B respectively are removed. The attachment members are then introduced in groove 2 of sections 1A and IB respectively, whereupon the screw 4 carrying the clamping member 6B and rubber gasket 7 is introduced through the holes in the attachment members 3A, 3B, whereupon the upper rubber gasket 7 and clamping member 6A is mounted upon the upwardly projecting end of the screw, after which the nut is screwed on and tightened when the sections have been brought into the desired angular position with respect to each other. By tightening the nut 5 the sections 1A and IB are thus fixed with respect to each other in the transverse direction as well as in the longitudinal direction and in a certain angular position. The presence of the rubber gasket 7 results in that the joint, which per se is rigid, obtains a certain elasticity, which • advantageously prevents or reduces transmission of vibra- OMPI WHO " tions through the joint. Figures 4 - 6 illustrate a preferred embodiment of the attachment means according to the invention used in a joint corresponding to the joint shown in figures 1 - 3. The preferred embodiment of the attachment means differs from the embodiment shown in figures 1 - 3 in that the attachment members 3A, 3B have been given a somewhat different shape. As appears from Fig 4 the attachment members 3A and 3B extend from the portion which is bent into hook-form in the direction towards the screw 4 and beyond this right into the groove 2 in the opposite section IB and- 1A respectively. The reason to this is as follows. Since the end of the attachment member which is bent into hook-form shall be introduced into the groove 2 through the slot, this must be designed to have a width that is greater than the thickness of the attachment member. In the embodiment shown in Fig 1 this may involve a certain risk of play. In the preferred em¬ bodiment according to figures 4 - 6 this is avoided due to the fact, that the width of' the slot with a certain minor play corresponds to the total thickness of the attachment members 3A and 3B. This results in that the hook-shaped part of the attachment member easily be intro¬ duced through the slot of the groove 2, the second attach- ment member on mounting being made to project into the slot so that the play wilT then be very small. The joint will thus become more rigid since the risk of play practically has been eliminated. The preferred embodiment of the attachment member 3A and 3B also differs from -the embodi- ment. previously described in that the hook-shaped end forms an acute angel, preferably 40 - 45° with the longi¬ tudinal side of the attachment member as shown in Fig 6. The object with this is to make it more easy to connect two rod-like sections 1A, IB with each other so that the sec- tions form an angel greater than 90° even up to about 180°, as indicated in dash-and-dot lines in Fig 5. For this pur¬ pose the attachment members 3A, 3B in Fig 5 are shown in a position at the ends of the two sections 1A, IB respective¬ ly. Otherwise the attachment members may of course be posi- tioned in any desired position along the groove 2 between the ends of sections 1A, IB. The embodiment illustrated in figures 4 - 6 corresponds in other respects with the embodiment described with refer¬ ence to Fig 1 - 3, and reference is otherwise made to the description relating to said figures. Figures 7 and 8 illustrate an embodiment of the attach¬ ment means according to the invention which is adapted for connecting two smooth tubes 8 with each other. The attachment members 3A, 3B have been modified so that each attachment member consists of a circular washer having a radially pro¬ jecting arm with a circular cross section, the end of said arm being bent to form a hook. The tubes are each provided with a bore 9, having sufficient dimensions to render possible the introduction of said hook-shaped portion of the attach- ment member. In other respects the attachment member corre¬ sponds to the embodiment previously described and is mounted in the manner previously described. By means of the attach¬ ment member modified as mentioned two smooth tubes may thus be connected with each other and may be clamped with a de- sired angel between the tubes. Fig 9 shows a further modified embodiment of the at¬ tachment means according to the invention for connecting two e.g. smooth tube-shaped sections with each other. As appears from Fig 9 the attachment members 3A, 3B according to this embodiment are designed as tube clamps extending over a substantial part of the periphery of the tube. When the tubes 8 have been put into the attachment members 3A, 3B respectively which are formed as clamps, the attachment members are clamped against each other by tightening the nut 5 on the screw 4. The clamping member 6A is thereby pressed against both of the tubes 8 and the clamping member 6B against the outer surface of the attachment member 3A, 3B. In the embodiment shown in Fig 9 a rigid, circular metal washer 10 has been placed between the clamping member 6B and the lower rubber gasket 7. In other re¬ spects the attachment means correspond to embodiments described previously to which reference otherwise is made. The attachment members 3A, 3B respectively which are formed as clamps may also be designed so that it encloses practically the whole periphery of the tube and is provided with two lugs projecting in the direc¬ tions towards the attachment means, and through which the screw of the attachment means extends and which are clamped together between the clamping members 6A and 6B and the rubber gaskets 7. In this case the attachment members initially either will have to be passed onto the tube from the end thereof or at first will have to be widened for putting the tube thereinto and then again be closed for enclosing the tube. It should further be pointed out, that the embodiment according to Fig 9 does not require sections having tubular form or sections having circular cross section. The design of the attach¬ ment members 3A, 3B may of course be adapted to any shape of the cross section of the sections to be interconnected, e.g. square, hexagonal , oval or other cross section. In the embodiments described so far it has been as¬ sumed that the clamping members 6A, 6B are solids of revolu¬ tion in the form of truncated cones. It is, however ' , by no means any condition for the invention to have the clamping members designed in the form of solids of revolution.. The clamping members may instead be designed as truncated pyramids. In the embodiment shown in Fig 10 the clamping members 6B have been replaced by a flat bar 6B' of steel , forming a spacing member between two tubes 8 extending in parallel OMPI * wi p with each other. The design of the attachment members 3A, 3B for the tubes 8 should in this case suitably have a design corresponding to the design described in connec¬ tion with Fig 9. If the flat bar 6B' is relatively long, as indicated in Fig 10, it may be convenient to use two sets instead of one set of screws 4, nuts 5, washers 10 and rubber gaskets 7, as shown i Fig 10. In the arrangement shown in said figure the clamping member 6B' may also be used as a tube sup¬ porting member by means of which the tube package is sus- pended by means of any suitable suspension means, which in a manner not shown is attached to the attachment member 6B'. The invention which above has been described with re¬ ference to a number of embodiments, is not limited to the embodiments disclosed but may be subject to several varia- tions within the scope of the appended claims. The clamp¬ ing members 6A, 6B may for example have a trapetzoidal or triangular cross section seen in a section taken perpen¬ dicularly with respect to the screw 4, which results in a fixed angular adjustment between the sections which are interconnected by means of the attachment means.

Claims: CLA IMS 1. Attachment means for securing two, preferably rod- shaped objects with respect to each other, comprising two clamping members (6A, 6B) which by means of tightening members, preferably screw and nut (4, 5) are adapted to be tightened towards each other thereby exerting a wedging effect on two objects (1A, IB, 8) to be connected with each other, resulting wedging forces being taken up as a traction force in two attachment members (3A, 3B), sup¬ ported by said clamping members (4, 5) and each one re- tainingly engaging one of the objects to be connected with each other, c h a r a c t e r i z e d in that said at¬ tachment elements (3A, 3B) are disposed in each other over- lapping position between the two clamping members (6A, 6B), and in that both clamping members on being tightened to¬ gether, exert a clamping force on the two each other over¬ lapping attachment members and at the same time exerting a wedging force on the objects to be connected with each other. 2. Attachment means according to claim 1, c h a r a c ¬ t i z e d in that two rigid but resilient members are disposed between said clamping members on opposite sides of the attachment members overlapping each other in order to exert a resilient clamping force on the attachment mem- bers when being tightened together. 3. Attachment means according to claims 1 or 2, c h a r¬ a c t e r i z d in that the clamping members (6A, 6B) in a manner known per se are composed of solids of revolution tapered into wedge-shape, preferably frusto-conical solids of revolution, provided with a through hole for a screw (4), . and in that the clamping members (6A 6B) screwingra nut on the end of the screw can be pressed towards each other, and in that said attachment members (3A, 3B) each consists of a washer having a through hole therein for said screw (4), each of said washers having a projecting portion which is BURE OMPI ^ shaped to provide retaining engagement with one of the two objects (1A, IB) to be connected with each other. 4. Attachment means according to claim 3, c a r ¬ a c t e r i z e d in that said attachment elements 5 (3A, 3B) are bent into the shape of hooks at the pro¬ jecting end. 5. Attachment means according to claim 3, c a r ¬ a c t e r i z e d in that the projection portion of said attachment member is.shaped into the form of a 10 clamp-, which completely or partially encloses one of the two objects (8) to be connected with each other. 6. Attachment means according to any of the preceed- ing claims, c h a r a c t e i z e d in that said two attachment members (3A, 3B) are designed so as to 15 provide a shape-determined angular clamping of the attachment members with respect to each other. 7. Attachment means according to claim 6, c h a r ¬ a c t e r i z e d in that said two attachment members (3A, 3B) on two surfaces, which are adapted to be turned 20 towards each other, are provided with radially extending grooves for providing said shape-determined angular clamp¬ ing when under the influence of a force being brought into contact with each other. 8. Attachment means according to any of the preceeding 25 claims, c h a r a c t e r i z e d in that said resilient members consist of rigid, resilient rubber gaskets (7) provided with a through hole for a screw (4). 9. Attachment means according to any of the preceeding claims., c h a r a c t e r z e d in that said clamping 30. members (6A, 6B) consist of frusto-conical solids of re¬ volution made of hard plastic material. 35 IfU E OMPI

Inventors: DAHL LEIF, HENCKEL PETER, HINN LARS, ROSENGREN KENT, SIHLBERG HENRY, DAHL, LEIF, HENCKEL, PETER, HINN, LARS, ROSENGREN, KENT, SIHLBERG, HENRY
Applicants: DAHL LEIF, HENCKEL PETER, HINN LARS, ROSENGREN KENT, SIHLBERG HENRY, DAHL, LEIF, HENCKEL, PETER, HINN, LARS, ROSENGREN, KENT, SIHLBERG, HENRY
Application year: 1984
Main classification: F16B7
IPC codes: F16B7