Method and fixing arrangement for the mounting of door fittings

Abstract: The invention concerns a method and a fixing arrangement, said method comprising the mounting of a door fitting (8), for example a door handle rosette, on two opposing sides (14) of a door leaf/a door plate, in which door leaf/plate there is provided at least one through-going hole (15), and comprising a fixing arrangement (1) consisting of an elastic expandable material and comprising a hollow leg (2) with a first outer diameter (6) and with a first inner diameter (5) in the formation of the cavity (9) along the whole of the longitudinal axis of the leg (2), said leg (2) terminating at each end in a first (11) and a second (12) end surface. At least one fixing arrangement (1) is placed with its one end part on and surrounding a threaded stub (3) provided on the one door fitting (8), and the door fitting is then placed on the one side of the door with the fixing arrangement(s) in the holes provided in the door, and the second door fitting/the second rosette (8) comprising mounting holes is placed on the opposite side of the door, through which holes a trap-screw (16) is inserted, said trap-screw (16) sliding into the inner cavity (9) in the fixing arrangement (1).

Description: The invention relates to a set of door fittings, such as door handle rosettes, the set comprising a first fitting, a second fitting and at least one fixing arrangement with a corresponding screw for the mounting of the fittings on two opposed sides of a door, the fixing arrangement having the form of a hollow leg with a first end surface and a second end surface for abutment against each of the fittings, respectively, the area at the first end surface being receivable around a stub on the first door fitting, said stub having a threaded hole for screwing in of a thread of the screw, the second door fitting having a mounting hole for insertion of the screw so that a head of the screw abuts the second door fitting around the mounting hole. The set of door fittings is characterized in that the screw is a trap-screw and under its head has a further head in the form of a so-called trap which by screwing in of the screw to its mounted position enters the hollow leg of the fixing arrangement at its second end surface and thereby expands the fixing arrangement. The invention also relates to a method of mounting a set of door fittings, such as door handle rosettes, on opposed sides of a door, the set comprising a first fitting, a second fitting and at least one fixing arrangement with a corresponding screw having a head, the fixing arrangement having the form of a hollow leg with a first end surface and a second end surface for abutment against each of the fittings, respectively, whereby the fixing arrangement with the area at its first end surface is placed around a stub on the first door fitting, the first door fitting is placed on a first side of the door so that the fixing arrangement extends through a hole in the door, the second door fitting is placed on a second side of the door and the screw is inserted through a mounting hole in the second door fitting, inserted through the hollow leg of the fixing arrangement and screwed into a thread of the stub on the first door fitting. The method is characterized by that a further head in the form of a so-called trap placed under the head of the screw, which has the form of a trap-screw, by screwing in of the screw to its mounted position enters the hollow leg of the fixing arrangement at its second end surface and thereby expands the fixing arrangement to abutment against the wall of the hole in the door. In connection with the mounting of door fittings and the like, it is a problem with the known solutions that these require that the hole which is drilled in the door corresponds substantially to the diameter of the thread on the screw in order that there shall not be too loose a fit, and so that the screws do not work themselves loose with time. It is customary, however, that the tradesmen carry out a pre-drilling of a hole in the door, and for this hole to be substantially larger than the actual diameter of the screw, which means that a loose fitting takes place and that the screw will work itself loose with time. The solution to this will thus be to produce the fittings in different sizes, so that the stubs provided on the fittings correspond substantially to the diameter of the drilled hole. However, this would give rise to a relatively large stock of products. Moreover, such a solution does not allow for the fact that when a tightening is effected, the two sides of the door move towards each other, in that there is no internal counter-resistance. Furthermore, it can be difficult to engage the stub by means of the end of the thread on the screw. From DE-A-2,837,614, a mounting of door fittings is known where the mounting units constitute an integrated part of the door rosettes, and where the fitting of the mounting units and herewith the door rosettes is carried out individually depending on the thickness of the door. Moreover, the mounting units are configured in a stiff, non-expandable material, which means that the pre-drilling must be effected with great accuracy. A fixing arrangement for door rosettes and the like is known from German patent publication no. 2,615,322. In this publication, the fixing arrangement consists of two or three parts made of a plastic material, which are put together to form an assembled plastic part. The arrangement comprises several loose parts, which means that it is difficult and troublesome to assemble in connection with the door rosette. Moreover, it is not possible to effect an expansion of the plastic part and thus ensure that this sits firmly in the hole drilled in the door. Furthermore, it is only in those cases where all three parts are assembled that the plastic part will serve as a bracing stay, in that in its normal two-part version, where only one plastic part sits in each side of the door, no rigidity is achieved around the door handle fixture. In these cases there will therefore be a distinct "sponge effect" when a tightening of the plates towards each other is effected. DE 94 18 266 U describes a set of two door fittings, of which one has prefitted sleeves with internal thread, and of which another has mounting holes corresponding to the sleeves and intended for the insertion of screws, which by the attachment of the fittings on either side of a door are screwed into the sleeves. By the attachment, bushings are placed around each sleeve and fitted tight in corresponding through-going holes in a lock case mounted in a recess in the door, whereby the door fittings are fixed securely in relation to the lock case, which in turn is secured in the door. It is the object of the present invention to provide a method which ensures control of the mounting screws, so that these enter into direct engagement with the threaded stubs on the one door handle rosette, and also that a good bracing arises as a consequence of the plug or fixing element extending in a continuous manner in the whole breadth of the door handle, and where by tightening an expansion of the plug takes place, so that the plug sits immovably firm in the drilled hole. It is also achieved that it is easy to "catch" the opposite side, in that the flexibility of the plug makes it possible to follow the holes, even though these do not extend in a straight line and/or at right-angles to the surface of the door. According to an embodiment of the method, on two opposite sides of a door leaf/door plate, in which door leaf/plate there is drilled at least one through-going hole, and comprising a fixing arrangement consisting of an elastic expandable material and comprising a hollow leg with a first outer diameter and with a first inner diameter in the formation of a cavity in the whole longitudinal axis of the leg, said leg terminating at each end in a first and a second end surface, at least one fixing arrangement with its one end part is placed on and surrounds a threaded stub provided on the one door fitting, and the door fitting is subsequently placed on the one side of the door with the fixing arrangement(s) in the holes provided in the door, and on the opposite side of the door is placed the second door fitting/the second rosette comprising mounting holes through which a trap-screw is inserted, said trap-screw sliding into the inner cavity of the fixing arrangement. In connection with the use of the fixing arrangement, there is thus first carried out a clamping of the conical end of the fixing arrangement on the threaded stub which sits on the rosette, either integrated herewith or disposed loosely in a hole arranged for this purpose in the rosette. After this has been pressed in, the complete rosette is now set in place in the holes which are in the door. It is ensured that the length of the fixing arrangement corresponds to the thickness of the door, which can be done by cutting the fixing arrangement to a suitable size. It is thus characteristic that the fixing arrangement is a loose unit, for which reason the door fittings are produced smooth with holes for mounting, including mounting of thread-stubs, or with at least one integrated thread-stub on at least the one door fitting. A rosette is then mounted from the other side, and a screw is now inserted through the holes in this rosette. The screw used is a so-called trap-screw, which is characterised in that it has at least a thread in the one end, and under the head at the other end it has a further head with a diameter which is less than the outermost head, but still larger than the thread on the screw. This trap-screw is inserted into the fixing arrangement, and when it meets with resistance, a screwing-in is effected. It is thus easy to engage the threaded stub on the other door rosette as a consequence of the screw being guided via the fixing arrangement. The screw is screwed in to the bottom, and in that the screw is configured with said under-head, which is designated a "trap", an expansion of the walls of the fixing arrangement occurs, whereby these will expand out against the limiting surfaces of the hole. It is hereby ensured that the screw sits firmly in its attachment. Due to the through-going extent of the fixing arrangement, it is also ensured that a bracing between the door plates is effected. It is thus important that the leg in the other area has an outer diameter which exceeds the rest of the fixing arrangement, in that this ensures that the part which is placed over the stub and is subsequently inserted in the pre-drilled hole, sits tightly between the surrounding walls of the hole and the outer walls of the stub itself. It is also important that the fixing arrangement is a loose unit, i.e. it is not integrated with the door fittings. By providing a method according to the invention and further being characterized by that after a certain movement through the cavity, the trap-screw is screwed in and cuts a thread on the inside of the fixing element, it is achieved that a locking of the screw occurs at the moment it cuts a thread in the elastic material before it is screwed firmly in the primary thread in the threaded metal stub on the opposing side. By providing a method according to the invention and further being characterized by that, when it is screwed in, the trap-screw with its trap part expands the second end part of the fixing element into abutment with the inner surfaces of the hole, it is achieved that an expansion of the fixing arrangement occurs, in that the trap on the screw is drawn into the fixing arrangement by the screwing-in of the screw, whereby an expansion of the material occurs which is pressed and lies tightly between the walls of the hole and the outer surface of the trap itself. As discussed earlier, the invention also concerns a fixing arrangement as disclosed in the introduction, and where the leg in the one end area - the plug-stub area - has an outer diameter which exceeds the first outer diameter, said plug-stub area extending from the first end surface of the fixing arrangement and for a given distance from this surface. The fixing arrangement is particularly suitable for use in connection with the method as described above. By configuring the fixing arrangement according to the invention and the fixing arrangement for the mounting of door fittings, for example door handle rosettes, consisting of an elastic expandable material comprising a hollow leg with a first outer diameter and with a first inner diameter in the formation of a cavity along the whole longitudinal axis of the leg, said leg terminating at each end in a first and a second end surface, and being characterized in that the leg in the one end area - the plug-stub area - has an outer diameter which exceeds the first outer diameter, said plug-stub area extending from the first end surface of the fixing arrangement and for a given distance from this surface, it is further achieved that the mounting of the door fitting adapts itself to the holes pre-drilled in the door plate, so that only a small product range of both fittings and fixing arrangements is necessary. By providing the fixing arrangement according to the invention and further characterized in that the cavity comprises a second inner diameter which is smaller than the first inner diameter, said second inner diameter extending in an area at a distance from the end surfaces of the fixing arrangement, there is achieved the forming of an area, the so-called thread-lock, where the result of the narrowing-down is that the screw will cut a thread in the elastic material. The inner diameter of the plug-stub area may be larger than the inner diameter of the remaining part of the cavity, and the inner cavity of the plug-stub area may be conical with the largest diameter towards the end surface. The leg may on its outer surface be provided with with at least one longitudinal fluke which extends parallel with the longitudinal axis. By providing the fixing arrangement according to the invention, it is achieved that the plug-stub area has some dimensions which are suitable in connection with the pressing-on of the stub of the door handle/rosette. By providing the fixing arrangement according to the invention, with these flukes it is achieved that the fixing arrangement is prevented from turning when the screw cuts a thread in the thread lock itself. It is expedient for four longitudinal flukes to be provided, these being disposed with 90° displacement on the outer surface of the fixing arrangement. The invention will now be explained in more detail with reference to the drawing, where Fig. 1 shows a longitudinal section through a fixing arrangement according to the invention, Fig. 2 shows a sectional view of the fixing arrangement shown in fig. 1 placed in a door, and in which fixing arrangement a trap-screw is mounted, Fig. 3 shows a fixing arrangement according to the invention seen from the one end. Fig. 1 shows a fixing arrangement 1 produced in an elastic and expandable plastic material, for example nylon. The fixing arrangement comprises a leg part 2 formed as a cylinder and with an outer diameter 6 and an inner diameter 5, said inner diameter 5 forming a cavity 9 into which a screw can be inserted. The leg part 2 of the fixing arrangement terminates in a second end surface 12 which extends substantially at right angles to the longitudinal axis of the leg part. The leg part continues over in a plug-stub part 10 which is similarly cylindrical in configuration, but its outer diameter exceeds the first outer diameter 6. The inner diameter of the plug-stub part 10 is similarly larger than the first inner diameter 5, and is preferably conical in configuration with the largest diameter facing towards its end surface, i.e. the first end surface 11. This end surface extends parallel with the second end surface 12. By configuring the plug-stub part as described, it is ensured that its outer diameter lies against the hole which is drilled in the limiting, surrounding surfaces of a door, and that the inner part is such that it fits the stub which is fastened to a door rosette/fitting. The fixing arrangement also comprises an area in the leg part 2 which has a smaller diameter than the inner diameter 5, this inner diameter 13 being preferably 0.3 mm smaller. There is hereby formed a lock part, i.e. that when the screw is inserted in the fixing arrangement via the cavity and starting from the second end surface 12, the screw will meet with resistance when it reaches the thread-lock part 4, which means that when the screw is rotated, the cutting of a thread is effected in the inner surface of the thread-lock part. Fig. 3 shows a cross-section of the fixing arrangement 1 shown in fig. 1 seen from the one end, and where it will be seen that its outer surface is provided with so-called flukes 7, preferably four in number, which extend parallel with the longitudinal axis of the leg part and are displaced 90° in relation to one another. With these flukes it is prevented that the fixing arrangement turns when the screw cuts the thread in the thread-lock 4. Fig. 2 shows the fixing arrangement 1 when this is mounted in a door, and thus the figure shows two door plates 14 extending in parallel and through which at least one hole 15 has been drilled, and where on the outer side of each door plate there is a door fitting 8, for example in the form of a door rosette. The diameter of the hole is typically in the order of 8 mm. A lock-casing 20 is inserted between the door plates. The mounting is carried out in that the one door rosette, on its surface facing towards the door plate 14, is provided with at least one threaded stub 3, and the fixing arrangement 1 is pressed with its plug-stub part down over the thread-stub part, so that this sits firmly on the rosette. The door rosette with the legs is now inserted in the holes arranged for this purpose in the sides of the door plates 14, and from the other side a correction of the leg length is carried out, in that this leg part 2 is cut off so that it corresponds to the thickness of the door. Hereafter, the second door fitting 8 is mounted, this having holes in which two screws are placed. As a consequence of the fixing arrangement 1 extending the whole of the way through the door, in connection with the mounting it is easy to guide the screws directly into engagement with the threaded stubs on the opposite fitting, in that the inner cavity of the fixing arrangement 1 serves as a guide. When the screw meets with resistance, in that it has now reached the thread-lock part 4, it is screwed in, and by this screwing-in a thread is cut in the inner surface of the fixing arrangement. The screw is screwed in right to the bottom. In that a so-called trap-screw is used for the mounting, it is ensured that the area at the second end surface 12 of the fixing arrangement 1 expands in such a manner that the leg parts are pressed out into abutment with the surrounding surfaces of the hole. It is hereby ensured that the fixing arrangement etc. sits firmly without any risk of the screw working itself out. Here it is important that use is made of a so-called trap-screw 16, which is characterised in that the axis part comprises a tread part 17, and where the head part 18 in the area under the head has a so-called trap 19, said trap being characterised in that it has a diameter which is larger than the diameter of the thread itself, but is smaller than the actual head part. The plug thus serves as a bracing stay, in that it increases the rigidity around the door handle fitting, and particularly in connection with doors of steel plate there is a distinct sponge effect which is prevented by the present invention. The effect of the fixing arrangement is thus that the mounting of the fitting adapts itself to the holes which are pre-drilled in the door plate, said holes lying typically around 8 mm old. The dimensions of the plug are thus preferably a length of approx. 75 mm, which is adapted to the relevant door thickness, an outer diameter 6 of 5.3 mm and an inner diameter 5 of 3.9 mm which, however, at the thread-lock lies at around 3.7 mm old. The length of the actual plug-stub part is preferably 11-12 mm, and it has an inner diameter of 5.1-5.7 mm, in that as mentioned the diameter is changed when the inner cavity of the plug-stub part is conical in shape. The fixing arrangement available for use with standard doors of 40 mm has a length just under 40 mm. The flukes provided on the outer surface of the fixing arrangement 1 have a thickness which is typically 0.75-1 mm, and a height of approx. 0.2 mm. These are provided on the external side of the plugstubs. The plug can be used both in connection with "loose" polygon thread-stubs which are secured by polygon-shaped holes in the door handle plate/rosette, or in connection with bolt-welded thread-stubs. The effect of the plug as spacing stay in "soft door types" with only slight inner counter-resistance, e.g. steel plate doors, is certainly not unimportant. In practice the stay effect is obvious. The problem with "soft doors" is known to those familiar with the art. By expansion of the leg of the plug, a dish-shaped distension is formed around the screw's "trap", and this lies up against the rear of the door handle plate/rosette, so that the plug, stiffened by the screw, forms a through-going spacing stay which effectively prevents that the mounting of door fittings with through-going screws gives rise to an undesired partial pressing together of the opposing sides of the door plates. In the mounting of door fittings with through-going screws, it is a known fact that it is difficult to get the ends of the screws to engage with the threaded-stub on the opposing side, especially in the case of thick doors. The configuration of the plug according to the invention with through-going plug leg affords the advantage that the through-going mounting screws are led directly into the opposing thread-stubs. This provides convenient mounting, and is not without significance with regard to the mounting time, which seen from the tradesman's point of view is a part of the product price.

Claims: A set of door fittings (8), such as door handle rosettes, the set comprising a first fitting, a second fitting and at least one fixing arrangement (1) with a corresponding screw (16) for the mounting of the fittings on two opposed sides of a door (14), the fixing arrangement having the form of a hollow leg with a first end surface (11) and a second end surface (12) for abutment against each of the fittings, respectively, the area at the first end surface (11) being receivable around a stub (3) on the first door fitting, said stub having a threaded hole for screwing in of a thread of the screw (16), the second door fitting having a mounting hole for insertion of the screw so that a head (18) of the screw abuts the second door fitting around the mounting hole, characterized in that the screw (16) is a trap-screw and under its head (18) has a further head in the form of a so-called trap (19) which by screwing in of the screw to its mounted position enters the hollow leg of the fixing arrangement (1) at its second end surface (12) and thereby expands the fixing arrangement (1). A set of door fittings according to claim 1, characterized in that said further head (19) of the screw (16) is tapered off in the direction of the screw thread (17). A set of door fittings according to claim 1 or 2, characterized in that the inner shape of the hollow leg of the fixing arrangement (1) in the area at the first end surface (11) is conical. A set of door fittings according to any one of the preceding claims, characterized in that the hollow leg of the fixing arrangement (1) in the area at the first end surface (11) has an outer diameter that is larger than a first outer diameter (6) of the fixing arrangement (1). A set of door fittings according to any one of the preceding claims, characterized in that the hollow leg of the fixing arrangement (1) has a first inner diameter (5) and a second inner diameter (13) that is smaller than the first inner diameter (5) and thereby forms a thread-lock part (4) for the screw (16), so that the screw by rotation cuts a thread in the inner surface of the thread-lock part (4). A set of door fittings according to any one of the preceding claims, characterized in that the hollow leg of the fixing arrangement (1) in the area at the first end surface (11) is provided with flukes (7) on its outer surface. A fixing arrangement (1) and a corresponding screw (16) for the mounting of a first and a second door fitting (8), such as door handle rosettes, on two opposed sides of a door (14), the screw having a thread (17) and a first head (18), the fixing arrangement having the form of a hollow leg with a first end surface (11) and a second end surface (12) for abutment against each of the fittings (8), respectively, the hollow leg of the fixing arrangement (1) having a first inner diameter (5) that is larger than the diameter of the thread (17) of the screw (16), characterized in that the screw (16) is a trap-screw and under its first head (18) has a second head in the form of a so-called trap (19) composed of a first substantially cylindrical section with a diameter smaller than a diameter of the first head (18) and a second conical section connecting the first section with a part of the screw having a diameter smaller than the first inner diameter of the fixing arrangement (1), and in that the hollow leg of the fixing arrangement is expandable and has a second inner diameter (13) that is smaller than the thread (17) of the screw (16). A method of mounting a set of door fittings (8), such as door handle rosettes, on opposed sides of a door (14), the set comprising a first fitting, a second fitting and at least one fixing arrangement (1) with a corresponding screw (16) having a head (18), the fixing arrangement having the form of a hollow leg with a first end surface (11) and a second end surface (12) for abutment against each of the fittings (8), respectively, whereby the fixing arrangement with the area at its first end surface (11) is placed around a stub (3) on the first door fitting, the first door fitting is placed on a first side of the door (14) so that the fixing arrangement (1) extends through a hole (15) in the door, the second door fitting is placed on a second side of the door and the screw is inserted through a mounting hole in the second door fitting, inserted through the hollow leg of the fixing arrangement (1) and screwed into a thread of the stub (3) on the first door fitting, characterized by that a further head in the form of a so-called trap (19) placed under the head (18) of the screw (16), which has the form of a trap-screw, by screwing in of the screw to its mounted position enters the hollow leg of the fixing arrangement (1) at its second end surface (12) and thereby expands the fixing arrangement to abutment against the wall of the hole (15) in the door (14). A method of mounting according to claim 8, characterized by that the screw (16) by rotation cuts a thread in an inner surface of a thread-lock part (4) of the hollow leg of the fixing arrangement (1).

Inventors: FREILEV ERIK, FREILEV, ERIK
Applicants: NT RANDI AS, NT RANDI A/S
Application year: 2000
Main classification: E05B15
IPC codes: E05B15, E05B9