FIXING DEVICE FOR FASTENING IN THROUGH HOLES IN WALL OR CEILING PLATES

Abstract: A fixing device for fitting into a through hole (5) in a wall or ceiling plate or board (4) for fixing an object with the aid of a coacting screw (2). The device includes in a fitted state a collar (7) placed in the hole mouth, the collar being joined together, using a spring element (8), with a metal toggle formed in the shape of a channel section, inserted through the hole in the board and engaging against the back of the board by reason of the bias of the element (8). The joint between the toggle (6) and the spring element (8) is made with the aid of a connector (13), snappable in place between the flanges of the toggle, the spring element being fastened in the connector and centered against a threaded hole (14) arranged in the toggle for coaction with the screw (2).

Description: FIXING DEVICE FOR FASTENING IN THROUGH HOLES IN WALL OR CEILING PLATES. TECHNICAL FIELD The present invention relates to a fixing device for fastening in through holes in wall or ceiling plates, boards and the like, the device being intended to coact with a screw or the like for fixing an object to the board. In its fitted state the device includes a holed collar engaging in the mouth of the hole in the board at the front thereof, a toggle active in this fitted state such as to engage against the back of the board, and which prior to fitting the device is disposed to assume an inactive position substantially at right angles to its active position enabling ' it to be passed through the hole in the board when fitting the device, which also includes an intermediate, cylindrical spring element guiding the coacting screw, the end portions of this element being respectively fastened in the collar and connected to the toggle, the element being adapted such as to open out the toggle by its spring bias into the active position thereof when the toggle is free from the hole in the board during fitting, and also to pull the toggle into compressive engagement, against the back of the board. BACKGROUND ART Different types of fixing device similar to the invent¬ ive subject are already known. The devices of the prior art are, however, burdened with problems relating to both manufacture and use. The Swedish Patent No. 220572 teaches a fixing device having certain similarities in appearance with the inventive subject. However, the known device has a toggle made entirely from plastics, which has to be made substantially and thick walled to meet strength requirements set for it, and which must also be provided with a threaded, flanged metal insert in a hole intended for coaction with a screw. In turn, this has re¬ sulted in that in order to use the device a hole, which is large in relation to the diameter of the coacting screw, has to be made in the board to allow passage of the toggle, and also an extra cost has occurred for the manufacture of the metal insert and its assembly. In another fixing device known from the US Patent 2 567 372, a metal toggle of U- shaped cross section is used with a nut mounted in trunnions in the flanges of the toggle. In order to obtain sufficient strength in the nut and its trunnions, threaded onto the screw and turned at right angles to the longitu¬ dinal direction of the toggle during assembly, there has also been obtained in this case a toggle configuration requiring a large hole relative to the screw diameter for enabling the toggle to pass through the board, in addi- tion, this structure requires a further -spring element for a specially formed portion of the spring element normally required for a fixing device of the kind in question. This further spring element or element portion is arranged between the nut and toggle, and has the task during fitting the device of pivoting the toggle to its active position after its passage through the board. DISCLOSURE OF THE INVENTION The object of the invention is to reduce the number of details included in a fixing device of the kind discussed here in order to simplify, and thus cheapen its production. Another object is to increase the load capacity of the device while simultaneously reducing the diameter of the through hole in the board in relation to the diameter of the coacting screw. A still further object is to provide a fixing device which is resistent to heat, i.e. a device where the load carrying parts are not deformed when they are subjected to heat, e.g. from a lamp in an electric light fitting. These objects are attained by the fixing device being given the characterizing features disclosed in the follow¬ ing claims. DESCRIPTI idOhN OF FIGURES An embodiment of the invention will now be described in detail with reference to the accompanying drawing, on which Figures 1-5 schematically illustrate different operations in fitting the fixing device, starting with its inactive state in Figure 1 to its fitted state as fixing for an object fastened to it in Figure 5, Figure 6 illustrates a stage in the fitting of a fixing device in a board which is thicker in relation to the board of Figure 1, Figure 7 illustrates a fixing device in section at right angles to the longitudinal direction of the toggle, Figure 8 illustrates a fixing device sectioned in the lon¬ gitudinal direction of the toggle, Figure 9 is a view from below of a fixing device from which the collar and a portion of a connector disposed in the toggle have been removed, Figure 10 is a view from below of a complete fixing device. PREFERRED EMBODIMENT In the embodiment of the present invention illustrated in Figures 1-6, a fixing means 1 coacts with a screw 2 for fixing an object 3 (see Figure 5) to a board 4 provided with a through hole for this purpose. The fixing device comprises a toggle 6, a collar and an intermediate spring element 8, fastened at one end portion to the toggle and to the collar at its other end portion, and having the configuration of a helical spring in the illustrated embo¬ diment. The toggle is suitably made from sheet metal, while the material in the collar is preferably plastics. The implementation of the toggle 6 and collar 7 in the preferred embodiment is more closely illustrated in Figures 7-10, which also illustrate the implementation of a connector 13, via which the spring element 8 is connect- ed to the toggle. The toggle is elongate and formed sub¬ stantially as a channel section with curved flanges 12 departing from a web 11, which, due to its curvature in the longitudinal direction of the section, is divided into a central portion 15 with substantially constant flange height, and two end portions 16 with diminishing flange height towards the respective end of the toggle, there thus being formed flange edge 9 for engagement against a board 4. Each toggle end is formed with a tongue 10 having a function which will be described in detail below. A threaded through hole 14 is arranged in the central por¬ tion of the toggle for coaction with the screw 2. By fold¬ ing down the hole edge, a cylindrical portion 19 has been formed, which extends into a through hole 17 in a connector 13 adapted to the space between the flanges. One end portion of the helical spring 8 fastened in the connector is thus centered relative the hole 14. The connector 13 is attached to the toggle by two spring hooks 24 engaging in tabs 25 pressed down from the toggle web. The other end portion of the spring 8 is fastened into, and surrounded by a collar 7, see Figures 7 and 8, the collar comprising a cylindrical portion 29 with a through hole 18, through which the coacting screw 2 is intended to be guided into the spring 8. The cylindrical portion 29 is intended to be fitted into the hole 5 in the board 4 when the fixing device is fitted to the board, the outstanding flange 20 of the cylindrical portion 29 then being caused to engage against the front of the board 4. Buttresses 22 projecting out from the cylindrical portion are intended to grip in the hole wall to prevent the collar 7 from turning in the hole 5 during fitting. Furthermore, the cylindrical portion 29 is provided with concentrically arranged, arcuate, through slots 23, and in one of these one of the tongues of the toggle is inserted and is kept in place due to the spring 8 being stressed in an inactive state of the fixing device. This inactive state of the fixing device in which the device 1 and screw 2 are kept together as a unit is illustrated in Figure 1. The screw is inserted through the hole in the collar 7 and through the spring 8 to be kept with its end engaging against a curved portion of the spring and the edge of the hole 17 in the connector 13 illustrated in Figures 7-9. One of the tongues 10 on the toggle is inserted in one of the slots 23 in the collar 7 and the toggle is kept in this posi¬ tion by the spring 8, which is stressed when the toggle is in this position. Figure 2 illustrates the fixing device 1 and screw 2 in the position where the device has been passed so far into the hole 5 that the flange of the collar 7 is brought into engagement against the front of the -board 4. The next stage in fitting is illustrated in Figure 3. By pressing on the screw 2 the toggle 6 has been displaced through the hole 5 in the board 4 and out of engagement with the slot 23 in the collar 7, such that when the toggle leaves the hole 5 it is caused to assume the illustrated position by the bias of the spring 8. At this stage the screw 2 is now loosely disposed in the fixing device and can be withdrawn from it. When the pressure on the screw 2 ceases, the toggle 6 is brought into compressive engagement against the back of the board 4, as illustrated in Figure 4. Figure 5 finally illustrates an object 3 fixed to the board 4 with the aid of the fixing device 1 and screw 2. The insertion of the screw is guided by the spring 8 directly into the threaded hole 14 of the toggle 6. Figure 6 is intended to illustrate how the same fixing device can be used for different board thicknesses. The device of this Figure is exactly the same as the one illustrated in Figures 1-5, and the state illustrated corresponds to the one illustrated in Figure 4 and de¬ scribed above. The present invention has, as is mentioned above, the partial object of simplifying and cheapening production of fixing devices of the type in question, inter alia by re¬ ducing the number of details included in the device, but naturally also by simplifying the implementation of the details. A pair of similar devices have been described in the introduction, both being provided with separate th eaded metal inserts or nuts in the toggle for the co¬ acting screw. Both the number of details and the difficulty of assembly work make these fixing devices expensive to produce. Accordingly, there are six different details, apart from the screw, included in the fixing device provided with a plastic toggle according to the Swedish patent 220572, all of which have to be put to¬ gether. The associated collar has an unillustrated expan- sion on the flange side of the through hole 18, and the outmost turn of the spring 8 has at one end portion a corresponding diameter increase, which also increases the cost of the spring. During assembly, the spring is insert¬ ed in the collar from the flange side," the expanded por- tion of the spring being fitted into the expanded portion of the hole and the spring locked to the collar by a metal washer being pressed into the expanded portion of the hole. The free spring end is then taken through the hole in the toggle, which also has an expansion on the upper side of the toggle, which is not illustrated in the patent specification. A threaded metal sleeve is then inserted in the free spring end, this sleeve having a swollen portion on the portion inserted in the spring, its other end por- tion being terminated by a flange. The spring with its metal sleeve is then pressed back into the hole in the toggle. The three parts are locked to each other by the swelling and the flange, which fits into the expansion of the toggle hole on the sleeve. The helical spring used in the present invention is com¬ pletely cylindrical, and its end portions are molded re¬ spectively into the collar 7 and the connector 13, which is done in one operation in a tool producing a large number of fixing devices simultaneously. The fixing device thus merely comprises two details before assembly, namely the toggle 6 and a unit including the collar 7, spring 8 and connector 13. Assembly of these details is extremely simple, since the connector 13 is snapped into position in the toggle 6, where the hooks 24 engage behind the* tabs 25. The invention is of course not restricted to the embodi- ment described above, and may be varied in a plurality of ways within the scope of the inventive consept. Thus, for example, the fixing device can coact with some means other than a screw for fitting into a hole. The spring element may constitute something other than a helical spring, e.g. a sleeve of elastic material. Furthermore, the connector 13 may be made without spring hooks 24, and the toggle without the p"Unched-out tabs 25. Instead, for example, the flanges of the toggle may be provided with impressions or protrusions on the inside thereof, while the connector is provided with complement¬ ary depressions, the connector being pressed in between the toggle flanges, which move resiliently apart to allow the protrusions thereon to engage in the depressions in the connector corresponding to the protrusions.

Claims: C L A I M S 1. Fixing device (1) intended for fitting in a through hole (5) in a wall or ceiling plate, board or the like, the device being intended to coact with a screw (2) or the like for fixing an object (3) to a board (4), which fixing device includes a holed part or collar (7) engaging in the mouth of the hole in the board (4) at the front thereof, a toggle (6) active in this fitted state such as to engage against the back of the board (4), said toggle prior to fitting the device being disposed to assume an inactive position substantially at right angles to its active position, enabling it to be passed through the hole (5) in the board (4), the device also includ¬ ing an intermediate, cylindrical spring element (8) guiding the coacting screw (2), the end portions of this element being respectively fastened in the collar (7) and connected to the toggle (6), the element (8) being adapted such as to open out the toggle (6) by its spring bias into the active position thereof when the toggle is free from the hole (5) in the board (4) during fitting, and also to pull the toggle into compressive engagement against the back of the board (4), c h a r a c t e r i z e d in that the toggle (6), which is preferably made entirely in metal, is formed substantially as a channel section comprising flanges (12) departing from a web (11), which is divided into a central portion (15) due to the curva¬ ture thereof in the longitudinal direction of the toggle, this middle portion having substantially constant flange height, the two end portions (16) of the toggle having decreasing flange height towards the respective toggle end, there being thus formed a flat edge underside (9) intended for engagement against the board, and in that the spring element (8) is connected, via a connector (13) placed in the space between the flanges in the central portion (15), with the toggle (6) and centered against a threaded hole (14) preferably at the center of the toggle web for said coaction with the screw (2). 2. Fixing device as claimed in claim 1, c h a r a c t ¬ r i z e d in that mutually opposing tabs, protrusions or edges (25) are disposed on the toggle (6) in the space between the flanges (12) and that mutually opposed hooks or edges (24) are disposed on the connector (13), said hooks, tabs or edges (24, 25) on both toggle (6) and connector (13) being formed such that they are brought into mutual engagement when the connector (13) is applied to the toggle (6) . 3. Fixing device as claimed in claim 1 or 2, c h a r ¬ a c t e r i z e d in that the end portions of the spring element (8) are respectively fixed to the collar (7) and connector (13) by molding.

Inventors: BECK KLAUS, JORUP PEDER, BECK, KLAUS, JORUP, PEDER
Applicants: THORSMAN & CO AB
Application year: 1986
Main classification: F16B13
IPC codes: F16B13, F16B35