DEVICE FOR ATTACHING AN EXPANDABLE MEMBER TO A PROFILED SECTION

Abstract: The invention relates to a device for attaching an expandable member (4) to a profiled section (1a) which has an edge-related, longitudinally extending channel (1f) which includes a constricted edge-related, opening provided part (1c) and an inner part (1f) defined by wall-parts, with the aid of a rotatably expandable member (4) having clamping surfaces (4f') which face towards the inner surfaces or wall-parts of the inner part, these clamping surfaces being intended to be brought into firmly clamping engagement with the wall-parts of the inner part in response to rotational movement, among other things. The expandable member (4) is comprised of at least one spring element provided with legs (4a', 4b') and located on one side of a lever arm (3b) which generates rotary movement. The device can be used to connect two mutually adjacent panels together e.g. separate display systems.

Description: TITLE OF THE INVENTION: Device for Attaching an Expand¬ able Member to a Profiled Sec¬ tion TECHNICAL FIELD The present invention relates generally to a device for attaching an expandable member to a profiled section or the like. In a specific application, such as in display systems, such profiled sections or like structural elements are provided with a groove or channel having mutually oppos¬ ing surfaces against which clamping surfaces on the expandable member are intended to act. For this more specific application, there is provided a device by means of which a first profiled section can be connected to a second profiled section, normally so that the sections will extend parallel with one another. For this specific application and more specific applica- tions the first profiled section will have a longitudi¬ nally extending, edge-related groove which faces towards an edge part of the second profiled section, and the second profiled section will present a longitudinally extending, edge-related groove which faces towards an edge part of the first profiled section. Each of these grooves presents a constricted, edge- related part provided with an opening, and an inner, larger part which is defined by wall-parts or mutually opposing surfaces. In order to obtain the aforesaid firm, but readily detachable connection, such as between a first profiled section and a second profiled section, there is used in each case a member which can be expanded by rotational movement, said member having clamping surfaces which face towards the inner, mutually opposing surfaces or mutually opposing wall-parts of the inner larger part. Each of these expandable members is intended to be rotated into clamping coaction with the wall-parts of said inner channel part. A device of the aforesaid kind is particularly suited for use in display systems, where the device is able to serve as section attachment means and can be placed at any desired position along the section, and is also able to serve as a connecting device between a shelf or the like and a vertically extending profiled section or panel, and is able to allow a first profiled section in a first display system to coaσt in the aforesaid manner with a second profiled section forming a part of said display system, or a first profiled section of a display system, can be brought into firm, but readily detachable coaction with a second profiled section forming part of another or a second display system. This latter application may require some modification and dimension changes to the components of said device, BACKGROUND ART Devices by means of which an expandable member can be attached firmly, but removably to a profiled section, panel or like structure or to connect a first profiled section to a second profiled section so as these sec- tions are positioned adjacent one another, is previously known in several different forms. It can be mentioned here that it is known to use a member which can be expanded by rotation and to position these members adjacent the end parts of the profiled section, so as to form a frame structure thereby. The present invention is not intended primarily this type of application. However, other devices of this kind adapted to cooperate with the profiled sections at any selected position therealong are known to the art. Devices of this kind known hitherto are based on the principle of using an expandable member which comprises two parts, which are brought to an expanded or a com¬ pressed state by means of a screw thread, such that when in an expanded state, said member will firmly connect a first profiled section to a second profiled section, and when in a compressed state will enable the firm connec¬ tion to be readily loosened. Also belonging to the prior state of the art is the construction illustrated in the Swedish Patent Applica¬ tion 89 03557-0. However, although this publication teaches a device for firmly, but releasably securing a hairpin-shaped expandable member to a profiled section or rail, the device is not adapted to enable two elon¬ gated elements or profiled sections to be joined at right angles to one another. For this purpose, it is necessary to provide a grooved engagement means where the groove is positioned perpendicular to the longitudi- nal axis of the elongated expandable member. The eccentric is accommodated fully within the expand¬ able member and a screwdriver or like tool is used as a lever arm. The device illustrated in publication DE-A1-1 500 683 teaches the use of two profiled sections which are joined in a central region by eccentric-like intermedi¬ ate means that can be rotated to a widened state in the outer region of the profiled section parts and a non- activated state in the outer region of said section parts. These members are rotated, or twisted, with the aid of a separate angled lever and are fully accommodated in the expandable member. Publication DE-C1-3 641 290 teaches a method of connect¬ ing together two mutually adjacent panels provided with grooved edge parts. This publication, however, teaches attachment devices which are of a completely different kind to the aforesaid known devices or to the inventive devices. The device taught by this publication includes a clamp- ing device having two nuts, each of which coacts with a rod having a right-hand thread and a left-hand thread respectively and the central part of which is provided with a part or nut-part adapted for rotation of the rod, so that when the rod is rotated, or twisted, the nuts are brought more tightly together and therewith anchor the edge surfaces or loosen the same. DISCLOSURE OF THE PRESENT INVENTION TECHNICAL PROBLEMS When studying the state of the prior art as described above, it will be seen that a technical problem resides in the realization of the significance of constructing a member which can be expanded in response to rotational movement and which can be readily placed at any selected position along the extension of a first profiled section or a panel, where the holding force is sufficiently strong to enable force to be exerted on the member in the longitudinal extension of the profiled section without causing the member to slide with elements nor¬ mally required in display systems. It will also be seen that a further technical problem is one of realizing the need of particularly dimensioning the dimensions of an at least 90°-rotatable lever arm, an eccentric section rotatable by the lever arm, and the expandable member used in relation to one another. Another technical problem is one of providing conditions which will enable one and the same expandable member to be used when securing to the profiled section or the panel a separate element capable of supporting a load, and also when securing two profiled sections or the like one to the other. A further technical problem is one of realizing that an expandable member constructed in accordance with the fundamental principles of the present invention can be readily placed at any selected position along the axial length of a first profiled section and a second profiled section and therewith create conditions for obtaining a fixed connection of said sections, even though the sections should belong to display systems of different kinds in which the profiled sections and the grooves or channels have mutually different cross-sectional shapes. It will also be seen that a technical problem resides in the provision of a member which will expand when rotated and which permits the presence of a very small gap between the first profiled section and the second pro¬ filed section, and primarily to provide a constant distance between the first profiled section and the second profiled section, even when these sections belong to mutually different display systems. In addition, it will be seen that a technical problem is one of realizing the significance of allowing the ex¬ pandable member to comprise at least one spring element, and also to realize that when a spring element is used, said element shall be located on one side of a lever arm that functions to effect rotary movement. Another technical problem is one of realizing the sig¬ nificance of dimensioning the spring element or elements so as to enable the. same to be inserted into their respective channels, in a non-expanded state, and also to enable the spring element to open in response to rotational movement of the lever arm to an extent such that the openable leg parts of the spring element will be brought into clamping contact with the mutually opposing or opposite wall-parts of the inner larger channel or groove part. It will also be seen that a technical problem resides in the construction of an expandable member which will include on each side of the lever arm abutment surfaces which will enable the expandable members to be brought into satisfactory coaction with said inner channel part, irrespective of the display system concerned, while spacing the first profiled section and the second pro- filed section apart at a distance corresponding to the thickness of the lever arm. It will also be seen that a technical problem is one of realizing the significance of configuring or forming eccentric sections which will cause legged spring ele¬ ments, preferably hairpin-shaped elements, to move from a non-expanded position to an expanded position, or vice versa, in response to said rotational movement. Another technical problem is one of realizing the ranges or limits within which the eccentric section of the lever arm shall work in order to obtain a satisfactory function and adaptation to the form of spring element used. Another technical problem is one of realizing the sig-. nificance of configuring the legs so that certain parts thereof are able to spring so as to afford an adaptation of the clamping force against the parallel wall-parts of the channel, even in the case of relatively large toler- ances. It will also be seen that a technical problem resides in realizing the significance of orientating the lever arm advantageously in relation to one or two longitudinally extending symmetry lines of the requisite eccentric section. Finally, it will be seen that a technical problem also resides in realizing the necessary dimensioning of the spring elements so as to enable said elements to be held by the channel against corotation with the lever arm. SOLUTION With the intention of solving one or more of the afore¬ said technical problems, the present invention is based on an earlier known device constructed to enable an expandable member to be firmly but readily removably attached to a profiled section or panel, or to join a first profiled section to a second profiled section, in a manner so that they will be orientated adjacent one another, and in which the first profiled section is provided with an edge-related, longitudinally extending groove or channel having a constricted edge-related part provided with an opening or channel entrance, and an inner, larger part defined by wall-parts. In order to make this firm connection possible, the member which expands in response to rotational movement is constructed further on known means which are provided with clamping surfaces that face towards the inner surfaces or wall-parts of said inner channel part and which are intended to be brought into clamping engage¬ ment with the wall-parts of said inner channel part in response to said rotational movement, wherein the ex- pandable member is comprised of at least one legged spring element. On the basis of this earlier known device, it is now proposed in accordance with the invention that said spring element is located on one side of a lever arm which forms part of the expandable member and which has an eccentric section and produces rotatory movement; in that the spring element, in a non-expanded state, is dimensioned for insertion into said inner channel part through its opening-provided, edge-related longitudinal¬ ly extending groove and when so inserted can be opened and expanded by the eccentric in response to rotary movement of the lever to an extent such that the expand¬ able parts of said spring element will be brought into requisite clamping action with the opposing wall-parts of said inner channel part. In further embodiments proposed in accordance with the invention and falling within the scope of the inventive concept, it is proposed that the expandable member is positioned adjacent one side of the lever arm and that a load-adapted section is positioned adjacent the other side of the lever arm. When two legged spring elements are used, said elements are each located on a respective side of the lever arm. According to one embodiment, each spring element shall have a hairpin-like configuration. When two spring elements are used, it is also proposed that abutment surfaces are provided on each side of the lever arm, these shoulders or abutment surfaces having an extension on one side of the lever arm corresponding to the thickness or being slightly greater than the thickness of the opening-provided part. Located on each side of the abutment surfaces is an eccentric section which is intended to move the spring element inserted into and held by the channel, from a non-expanded state to an expanded state, and vice versa. The eccentric section of the lever arm is adapted to act within that part of the leg portions, normally half of the leg portions, which are remote from the region at which the legs are joined. The legs of a hairpin-like spring element are dimen¬ sioned to spring within the part, normally half, of the leg portions which constitute the region at which the legs are joined, so as to permit the free, flexurally rigid leg parts of the spring elements facing away from the region at which the flexurally rigid leg parts are joined, to conform to the direction of the mutually opposing, parallel wall-parts. It is also proposed that the lever arm shall have the form of a disc having an arm-part formed integrally therewith, or the form of an arm-part or a removable rod. It is also proposed that the lever arm is disposed in a direction which extends perpendicular to, or at least almost perpendicular to, a longitudinally extending symmetry line of the eccentric section. It is also proposed that each of the two hairpin-like spring elements are dimensioned so that the elements are held against corotation with rotational movement of the lever arm by respective grooves. When securing a first profiled section or panel to a second profiled sectional panel to ' define an angle therebetween, it is necessary for the longitudinally extending symmetry line of an eccentric section to form said angle with the longitudinally extending symmetry line of an adjacent eccentric section. ADVANTAGES Those advantages which are primarily associated with the inventive device reside in the ability of firmly, but removably, securing an expandable member and of connect¬ ing a first profiled section to a second profiled sec¬ tion adjacent one another even when the profiled sec¬ tions belong to different display systems, and also to provide conditions in which a small and constant space can be obtained between the profiled sections, this space being corresponded simply by the thickness of the lever arm. The inventive rotatably expandable member has been found to provide an extremely good and readily adaptable clamping force and can be readily inserted into the groove of the profiled section and readily removed from said groove, with the clamping action of said member being actuable by rotating the lever arm through 90°. The primary characteristic features of the inventive device are set forth in the characterizing clause of the following Claim 1. BRIEF DESCRIPTION OF THE DRAWINGS A number of embodiments of devices which exhibit charac¬ teristic significance of the present invention will now be described in more detail with reference to the accom¬ panying drawings, in which Figure 1 is a perspective view of two separate display systems whose separate profiled edge sections can be joined together in accordance with the principles of the invention; Figure 2 is a sectional view of different groove cross- sections applicable to a first profiled sec¬ tion and a second profiled section forming part of the display systems shown in Figure 1; Figure 3 is a side view of a lever-arm part included in a rotation expandable member according to the invention, the function of which depends on the use of one or two spring elements, not shown, said number being dependent on the application concerned; Figure 4 is a top view of a first embodiment of a spring element, and shows the element in a non-expanded state; Figure 5 illustrates the spring element of Figure 4 in a fully expanded state, said element being brought to the shown state by rotation of an eccentric section through 90°; Figure 6 illustrates the clamping action afforded by the spring properties of the spring element against one wall-part of the inner channel part; Figure 7 is a horizontal view of the lever-arm part shown in Figure 3; Figure 8 is a top view of a second embodiment of a spring element; Figure 9 is a top view of a third embodiment of a spring element and shows the element in a non- expanded state; Figure 10 is a plan view of the spring element shown in Figure 9 in a fully expanded state; and Figure 11 illustrates an application which uses only one single spring element that coacts with an expandable member. DESCRIPTION OF EMBODIMENTS AT PRESENT PREFERRED Shown in perspective in Figure 1 is a first system 1 which comprises four frame parts, each of which sur¬ rounds a panel or plate and which are connected together in a known manner, normally hinged together. Figure 1 also illustrates a second display system, which also comprises a number of frame parts similar to the display system 1, but with the difference that the profiled sections used to construct the frames or the panels la and 2a have slightly different forms, as illustrated in Figure 2. Among other things, the present invention intends to provide the possibility of connecting a first profiled section la to a second profiled section 2a in a firm but detachable fashion, such that the profiled sections are orientated in the same plane and extend parallel with one another. As will be seen from Figure 2, the first profiled sec¬ tion la has an edge-related, lc, longitudinally extend¬ ing groove or channel lb which faces towards an edge part 2c of the second profiled section 2a, while the second profiled section 2a has an edge-related, 2c, longitudinally extending groove or channel 2b which faces towards the edge-part lc of the first profiled section la. Each of the channels lb, 2b, has a constricted or nar¬ rowed edge-related (lc, 2c) part lb', 2b' provided with an entrance-functioning opening, and an inner, larger space or part If, 2f, defined by wall-parts Id, le and 2d, 2e respectively. As will be seen from Figure 2 , the opening lb' is small¬ er than the opening 2b' and the wall-parts Id and lc are located closer together than the wall-parts 2d and 2e. As will be evident, from the following description, the spring elements and eccentric sections or parts need to be specially dimensioned for each particular application that has large dimensional differences, so that an equivalent or generally equivalent clamping action will be obtained in both channels. With the use of a plurality of rotationally expandable members positioned at the sections A, B, C and D in Figure 1, with, among other things, clamping surfaces which face towards the inner channel surfaces Id, le or wall-parts of the inner channel part If, the profiled sections la, 2a, are clamped firmly together as a result of the clamping surface being brought into firm clamping engagement with the wall-parts Id, le of the inner part 1 in response to said rotational movement. As will also be seen from Figure 2, the inner part If of the channel defined by the wall-parts of the first profiled section la has a greater depth than the corre- spending inner channel part 2f defined by the wall-parts 2d, 2e of the second profiled section 2a. Figure 3 is a top view of a lever arm included in the expandable member, said lever arm 3 having the form of a part-circular disc 3a and an arm 3b extending therefrom. Provided in the centre of the disc is an abutment sur¬ face 3c, an eccentric section 3d and an outer stiffening 3e (see Figure 7). In order to provide a complete expandable member, the lever arm 3 has one, normally two, spring elements, where one is shown in top view in Figure 4. The spring element 4 may be located adjacent the illus- trated flat side of the lever arm 3 in Figure 3, and a second such spring element 4', a hairpin-like element. 15 may be located on the other side (see Figure 7). The lever arm 3b is configured to execute rotary move¬ ment in relation to the spring elements when said elements are located in respective channels lb and 2b. As will be seen from Figure 4, the illustrated spring element has two legs (4a, 4b), which are joined together at a region 4c. Figure 4 also illustrates the configura- tion of the free and flexurally rigid leg parts 4a', 4b' of the spring element 4, and it will be seen that the two spring parts shall be opened slightly in order to be inserted so that the eccentric section 3d will be locat¬ ed within a recess 4d in the spring element. Figure 5 illustrates an operational state in which the eccentric section 3d of the lever arm 3 has been rotated through 90 * , therewith causing the free leg parts 4a', 4b' of the spring element to open fully to the position shown in Figure 5. The leg parts 4e, 4e' are bent inwards so as to allow, among other things, the region 4f and its clamping surface 4f' to take a near parallel position with a wall section Id, under the action of the eccentric section 3d. It will be evident from Figures 2 and 4 that when in a non-expanded state, the spring element 4 is dimensioned for insertion into a channel, through the opening-pro¬ vided part thereof, which means that the width "b" of the spring element shall be slightly smaller than the opening lb'. When the spring element is inserted, it can be opened in response to rotation of the lever arm to an extent such that the free, flexurally rigid leg parts 4a', 4b' will be brought into clamping action with the opposing and parallel wall-parts Id, le of the inner channel part, as shown in Figure 5, which means that the distance between these wall-parts shall be slightly smaller than the distance "b" between the free leg parts 4a', 4b' of the spring elements, as shown in Figure 5. As shown in Figure 7 , located on each side of the lever arm 3 are abutments 3c, 3c' having an extension on the side of the lever arm 3 which at least corresponds to the thickness of the part provided with the opening lb', i.e. the distance "σ" in Figure 2. Located on each side of the abutments 3c, 3c' is a respective eccentric section 3d, 3d', which, among other things, is intended, at the same time, to cause the spring elements (4, 4') inserted in the channels lb and 2b to move from a non-expanded state. The eccentric section 3d of the lever arm is intended to act within that half of the leg parts which are remote from the region 4c at which the legs are joined and where the leg parts 4a' and 4b' are flexurally rigid. The legs of a hairpin-like spring element are dimen¬ sioned so that within the half of the leg parts which constitute the region 4c at which the legs are joined, will spring to enable the free, flexurally rigid leg parts 4a', 4b' of the spring elements remote from said leg joining region 4c, to rotate or approach the paral¬ lel direction of the opposing wall-parts and take a more parallel position (shown in Figure 6) than the position shown in Figure 5. Although the lever arm has been shown in the form of a disc with an arm part formed integral therewith, it will be understood that the lever arm may, alternatively, also have the form of a single arm or a single rod. The lever arm 3b is positioned so as to be perpendicu¬ lar, or at least almost perpendicular, to a longitudinal symmetry line "S", of said eccentric section 3d. The two hairpin-like spring elements 4, 4' are held against corotation with movement of the lever arm 3b, by respective channels lb and 2b. Figure 8 is a top view of a second embodiment of a spring element. This element has a symmetrical oval shape, with a centre positioned recess 4d for accommo¬ dating the eccentric section. Figure 9 is a top view of a third embodiment of a spring element, and shows the spring element in a non-expanded state. This spring element has a section 4a', 4b' which tends to bend slightly, these sections 4a', 4b' provid¬ ing the clamping surfaces 4f' which engage with the parallel wall sections le and Id, as shown in Figure 10. The clamping surfaces may be serrated or likewise rough¬ ened. Figure 11 illustrates an embodiment which includes two similar expandable members and only one spring element 4, said spring element being shown in an expanded and firmly holding state. An angular part 10 coacts with the part 3a, and the part 3a is pivotally connected to the part 10 thus causing the profiled sections la and 2a to form a right angle with one another. As will be understood, the part 10 can be exchanged for an equivalent device, such as an eye, hook or the like for coaction with a member. When two profiled sections are to be joined together so as to define an angle therebetween, such as the connec¬ tion of horizontal or sloping shelving to vertically extending profiled sections or posts, the longitudinally extending symmetry line of an eccentric section 3d shall form an angle with the longitudinally extending symmetry line of the adjacent eccentric section 3d', so that rotation through 90° will result in secure clamping of the two members. The present invention also enables one spring element to be readily replaced with another, so as to enable the device to be adapted readily to the dimensions of dif¬ ferent systems. The configuration of the eccentric can also be changed. It will be understood that the invention is not res¬ tricted to the aforedescribed and illustrated exempli¬ fying embodiments thereof, and that modifications can be made within the scope of the inventive concept as de¬ fined in the following Claims.

Claims: CLAIMS 1. A device by means of which an expandable member (3, 4) can be firmly but easily removably connected to a profiled section (la) or which will enable a first profiled section (la) to be connected to a second pro¬ filed section (2a) with the aid of said member in a manner such as to orientate said profiled sections in relation to one another, wherein the first profiled section (la) has an edge-related, longitudinally extend¬ ing channel (lb) having a constricted or narrowed edge- related (lc) opening-provided channel part (la') and an inner channel part (If) defined by wall-parts of said section, wherein a rotationally expandable member having clamping sur-faces which face towards the inner surfaces or wall-parts of said inner channel part is intended to be brought into firm clamping engagement with the wall- parts of said inner part in response, among other things, to said rotational movement, and wherein the expandable member (3, 4) is comprised of at least one spring element provided with legs (4a', 4b'), c h a r a c t e r i z e d in that said spring element is located on one side of an eccentric section (3d) which functions to generate rotational movement and which includes a lever arm (3b) belonging to the expand¬ able member; in that the spring element (4), in a non- expanded state, is dimensioned for insertion into the inner channel part (If) through its opening-provided edge-related longitudinally extending channel (lb) and when so inserted rotation of the lever arm (3b) and its eccentric section (3d) will cause the spring element to open and expand to an extent such that the expandable parts (4a', 4b') of the spring element will be brought into requisite clamping contact with the mutually oppos¬ ing wall-parts (le. Id) of the inner channel part. 2. A device according to Claim 1, c h a r a c ¬ t e r i z e d in that the expandable member (4) is positioned adjacent one side of the lever arm (3b), and in that a load-adapted section is positioned adjacent the other side of the lever arm. 3. A device according to Claim 1, c h a r a c ¬ t e r i z e d in that two legged spring elements (4, 4') are each located on a respective side of the lever arm (3b). 4. A device according to Claim 3, c h a r a c ¬ t e r i z e d in that each spring element has a hairpin-like configuration. 5. A device according to Claim 3, c h a r a c ¬ t e r i z e d in that located on each side of the lever arm is a respective abutment (3c, 3c') whose extension on one side of the lever arm corresponds to and at least exceeds the thickness of the part provided with said opening or said channel. 6. A device according to Claim 5, c h a r a c ¬ t e r i z e d in that located on each side of the abutments (3c, 3c') is an eccentric section (3d, 3d') which is intended to act on a spring element inserted in respective channels and to cause said spring element to move from a non-expanded state to an expanded state, or vice versa. 7. A device according to Claim 5 or 6, c h a r a c ¬ t e r i z e d in that the eccentric section of said lever arm is intended to act within those parts of the leg portions (4a', 4b') that are remote from the region (4c) at which the legs are joined. 8. A device according to Claim 4, c h a r a c ¬ t e r i z e d in that when the spring element has a hairpin-like configuration, the legs of said element are dimensioned to spring within that part of the leg por¬ tions forming the region (4c) at which the legs (4a', 4b') are joined, so as to enable the expandable leg portions of the spring elements which are remote from the region at which the legs are joined to conform to the direction of said opposing wall-parts. 9. A device according to Claim 1, c h a r a c ¬ t e r i z e d in that the lever arm has the form of a disc (3a) with an integrally formed arm part, or has the form of a single arm, such as a rod. 10. A device according to Claim 1 or 6, c h a r a c ¬ t e r i z e d in that the lever arm extends perpendicu¬ larly, or at least generally perpendicularly, to a longitudinal symmetry line of at least one of said eccentric sections. 11. A device according to Claim 3, c h a r a c ¬ t e r i z e d in that the two hairpin-like spring elements are held against corotation with rotational movement of the lever arm by respective channels. 12. A device according to Claim 10, c h a r a c ¬ t e r i z e d in that one longitudinally extending symmetry line of an eccentric section forms an angle, e.g. an angle of 90 * , with a longitudinally extending symmetry line of an adjacent eccentric section.

Inventors: AHLBERG ERIK, CLAESSON ALF, AHLBERG, ERIK, CLAESSON, ALF
Applicants: MAXIBIT AB
Application year: 1992
Main classification: E04B1
IPC codes: E04H1, F16B2, F16B7, G09F15