GB2494462A - Hidden fixing for shelf - Google Patents

Abstract

A hidden support structure comprises a sleeve 2 and a dowel pin 1 retractably mounted within the sleeve 2; the sleeve 2 is inserted into a hole in the edge of a first object 8; the dowel pin 1 then extends into a hole in a second object 9 to fix the first 8 and second 9 objects together. The dowel pin 1 may include a spring 5 to urge the dowel pin 1 out of the sleeve 2 and may be retracted into the sleeve by insertion of a screwdriver or other tool through slot 7 so as to engage protrusion 4. The dowel pin may alternatively include teeth (fig 15) which are operated by a screwdriver. A sleeve is preferably inserted into the hole in the second object 9 to provide reinforcement.

Description

Invisible support structure.

The present invention relates to a hidden locator dowel for supporting elongate objects, such as for example alcove shelving planks. The standard way of fitting a shelf into an alcove is to bold the shelf in place, mark along the wall all around the alcove below the plank and fix batons against the wall for the shelf to rest on. This method is clumsy and gives an unproftssional impression.

The aim of the invention is to provide a support structure that is at the same time easy to fix and looks totally protbssional. Moreover it is invisible once the shelf is put up. If the shelf is to be taken down, the only sign of it having been there will be two holes in either side of the alcove wall which can easily be filled in and painted over.

The invention consists of sleeved dowel which is fitted into the shelf plank. in the most basic realization the dowel is spring loaded. The side walls of the alcove are drilled and sleeved and the shelf plank pushed into place and the dowels expand into the holes in the walls under the pressure of the springs. To enable the removal of the shelf without destroying the shelf or damaging the wall, the shelf plank has a slot in its underside to allow for the introduction of a pin or screwdriver for compressing the spring and thus retracting the dowel pin. The shelf can then be removed.

The invention finds many applications other than "flying" alcove shelves, it can be used in any situation where visible fixings are unwanted. Bannister spindles can be located in place by the invention. Fitted furniture units never quite meet the wall and need to have a filling element inserted into a narrow gap where visible fixings would not be tolerated. Damaged mullions can be replaced without the need for disassembling the whole structure. The list is endless.

Now, similar "bolt" type gadgets are commonly in use as dead bolts for doors. They usually come with a little lever handle to move the bolt into engagement with the door frame or out of it. Those gadgets are clearly not suitable for hidden shelf supports since the unsightly handle would be sticking out of the shelving plank somewhere.

Figures 1 to 25 show the invention in more detail.

Figures Ito 9 illustrate the basic realization of the invention.

Figure 1 shows sleeve/dowel pin assembly as seen from underneath.

Figure 2 shows the same assembly turned through 90°.

Figure 3 is view of the blunt, closed end of the sleeve and Figure 4 is a similar view of the opposite end of the assembly.

Figures 5 and 6 are longitudinal sections through the dowel/sleeve assembly with figure 6, again turned through 900 about its axis.

Figure 7 is a section on the line A-A in figure 6.

Figures 8 and 9 show the assembly in situ with the dowel extended into an alcove wall.

Figures 1 & 2 and 5 & 6 show the dowel pin(l) inside sleeve(2). The leading end of Dowel (I) is shaped as a blunt cone to help location in the alcove wall. Sleeve (2) has a blanked off end (6) against the inside of which one end of a coil spring (5) is supported. The other end of coil spring (5) bears against dowel pin (1) loading it for movement out of sleeve (2).

Dowel (1) shows a protrusion (4) along its side which engages slot (7) machined into Sleeve (2). Protrusion (4) contacts the front edge of slot (7) when dowel (1) is fully extended.

Sleeve (2) is inserted into a hole drilled into the edge of a shelving plank (8) (as seen on figures 8 & 9) until its end is flush with the edge of plank (8). In the underside of plank (8) a slot is machined in linc with slot (7) in the slccvc (2) such that it provides passage into sleeve (2) for a screw driver or similar tool to engage the leading edge of protrusion (4) and pull dowel (I) back into sleeve (2) against spring (5) to release shelving plank (8) from alcove wall (9). The outside of sleeve (2) shows small locator ribs (3) to assure a good tight fit in shelving plank (8).

The only modification of alcove wall (9) required is a hole drilled in an appropriate position that allows the dowel to engage it when it is extended beyond the open end of the sleeve under pressure of the spring.

The usual number of dowels to support an alcove shelf is four, two at each end of the plank.

For heavier duty shelves, extra dowels may be placed along the long edge of the plank with corresponding holes in the alcove walls.

The holes in the alcove walls may be lined to reduce the danger of damage to the wall and crumbling of the edges of the holes during assembly and disassembly.

Figures 10 to 18 show a second realization of the invention.

Figures 10 & II show the outside of the dowel sleeve (2) with the dowel inserted. Locator ribs (3) are seen along its length as in the first realization.

Figures 12 and 13 are end views from the rear and the front respectively.

Figures 14,15, and 16 are longitudinal cross sections through the sleeve and dowel showing the two halves (I) and (6) and their racks of teeth(7).

in figure 14 the dowel is frilly retracted into its sleeve (2) and in figure 15 it is expanded into the object to bc fastened.

Figure 16 is a section showing die tow dowel parts (1) and (6) extended ifilly and exposing the hole (4) which allows the screw driver to be introduced into the dowel sleeve (2).

Figures 17 and 18 are sections through B-B and C-C respectively of figures 14 and 15.

in the second realization the spring is omitted and replaced by a two part dowel (1 & 6), each part having a rack of teeth, each facing each other along the long sides of the dowel parts.

A cross-screw driver is inserted through the hole (4) in the sleeve (2) and turned to force the front end (1) out of the sleeve (2). The rear end of the dowel (6) is pushed against the closed end (5) of the dowel sleeve (2). This realization sports two oves on the inside of the sleeve (2) to avoid that the dowel turns inside the sleeve (2) and becomes inaccessible for adjustment from the outside.

Figures 19 to 25 show a simplified form of the non sprung dowel. The sleeve (2) is similar to the first realization and the dowel consists of a single part with teeth which are engaged by a screw driver or similar tool to push the dowel in or out of engagement with the object to be located in place by the invention.

Naturally, the invention is not limited to the realizations shown in the drawings. Other ways of pushing out and retracting the dowel pin niay be envisaged and other shapes of dowel pin and guiding sleeve cou'd be used. Such modifications would still form part of the invention.

Moreover, the invention is not limited to shelf fastening, but is suitable for trapping and locating various objects in between others. Examples are banister spindles on stairwells, which are equipped with a dowel at each end; replacing damaged niullions without dismantling the structure or end panels for closing gaps in fitted ftrniture such as kitchens & bathrooms. The skilled person will no doubt think of more possible applications of the dowel but they are considered to form part of the underlying invention.