WO1997044552A2

WO1997044552A2 - Device for locating an object in a wall

Info

Publication number: WO1997044552A2
Application number: PCT/NZ1997/000060
Authority: WO
Inventors: Paul Smith; Robert Wayne Mclellan
Original assignee: Pinz New Zealand Limited
Priority date: 1996-05-17
Filing date: 1997-05-16
Publication date: 1997-11-27
Also published as: WO1997044552A3; AU2916897A

Abstract

A steel pin (101) having a thread on one end and a point (202) on the other is a preferred locating apparatus for use during construction or renovations of a building, to specify the position of an electrical flush box (100), or the like concealed within a wall or a ceiling or a floor. The pin (101) preferably protrudes from a captive nut (203) which is normally part of the mounted flush box. When a wall panel (301) is applied, the pin (101) penetrates the panel (301) and signals the position of the now concealed flush box (100) so that a cutout through the panel may be made. The locating apparatus is then removed. Use of this device avoids the tedium of recording measurements prior to wall panel placement, damage to wall panels, and lost flush boxes within walls.

Description

DEVICE FOR LOCATING AN OBJECT IN A WALL

TECHNICAL FIELD OF THE INVENTION

This invention relates to the field of accessories for use during the construction of buildings, and more particularly relates to locator means for finding objects mounted within a wall, behind wall panels so that the objects can be exposed.

BACKGROUND

For many years a problem in the construction of a typical New Zealand house type of building (in which any exterior and interior wall is first constructed as a frame; then services such as electrical outlets or plumbing fixtures are placed against studs or other members of the frame; then wall panels are affixed onto the frames, and then the service outlets are exposed by cutting through the panels) has been that the positions of at least some of the service outlets are difficult or impossible to find. As a result time is wasted, panel repairs are required, and sometimes new outlets are fitted with considerable difficulty.

One common type of service outlet is the electrician's flush box - an open-faced box of standardised dimensions which will hold electrical apparatus such as switches and power sockets. An electrician will have previously fixed flush boxes against studs in the wall of a room become covered by the installation of wall panels of one kind or another. "Gibraltar board" - a kind of plaster board sheathed in paper - is one typical wall panel. Even with the best intentions a carpenter can forget to note the position of every flush box and even then, it is time-consuming to accurately record the position of each and every flush box so that it can be precisely exposed after the wall panel has been fixed. It is also time-consuming to repair (using plaster, for example) a panel ravaged by electricians mining for lost flush boxes. There are many walls in existence holding lost flush boxes.

One common construction method is to make holes in a sheet of Gibraltar board at the sites of any flush boxes (or the like) before the board is nailed onto the wall. Because flush boxes are usually placed against studs, many of the holes so made will be close to an edge of the Gibraltar board and so will significantly weaken the board. A number of panels are wasted in this way. While magnet-based detectors for finding the flush boxes (or in desperation, the location of nails within the timber framing) are sometimes used, when the frame is made of steel (growing in popularity) and the flush box is made of a plastic material, a magnet is not much use.

In some situations in some countries, electrical apparatus may not be contained within a box but simply held against a stud on a "C" plate, and eventually, when a switch plate is attached on the front of the wall panel, it is sufficiently well held onto the panel.

One problem with marking out the positions of flush boxes is that even if an accurate record of position is kept, there may be no fixed reference points from which to measure because the wall panel covers the entire surface of the room.

OBJECT

It is an object of the present invention to provide an improved system for locating the position of service outlets in a wall under construction, or one which will at least provide the public with a useful choice.

STATEMENT OF THE INVENTION

In a first broad aspect the invention comprises a method for construction comprising placement of a surface such as a ceiling or floor but particularly a wall, covering panel on a framework; the surface being laid over one or more devices held beneath the surface; where there is a requirement to expose at least a portion of the or each device by forming an overlying aperture through the surface, the method comprising:-

(a) nstallation on the or each device of locating apparatus capable of penetrating the surface covering panel without substantial damage,

(b) nstallation of the or each device on a framework ,

(c) astening a surface covering panel in place, so that the locating apparatus installed on the or each device deforms or penetrates the covering panel,

(d) oting the position of the or each locatuy apparatus and forming an aperture through the covering panel in a defined relationship to the or each locating panel.

In a second broad aspect the invention comprises a Locating apparatus for use during construction or renovations of a building; the locating apparatus being capable of indicating the position of a structure concealed within a surface (such as a wall), wherein the locating apparatus comprises an elongated member having a point formed on a first end, the member having detachable attachment means at a second end, and the member having sufficient length to provide for attachment to a structure and also to penetrate through a covering panel subsequently attached to the surface, the position of the rod thereby indicating the position of the now concealed structure.

In a related aspect the invention provides a locating apparatus as described above, wherein the rod is made of a tough metal material. Optionally the metal may be steel, and optionally the steel may be magnetised, to help in location should the point fail to fully penetrate the panel. Preferably the locating apparatus is magnetised as strongly as possible..

In another related aspect the invention provides a locating apparatus as described above, wherein the rod is made of a tough plastics material.

In yet another related aspect the invention provides a locating apparatus as described above, wherein the detachable attachment means of the rod comprises a screw thread.

In a further related aspect the invention provides a locating apparatus as described above, wherein the detachable attachment means of the rod comprises a weakened frangible zone capable of being broken off after use.

In a yet further related aspect the invention provides a locating apparatus as described above, wherein the apparatus includes attachment means compatible with an electrical flush box.

In a still further related aspect the invention provides a locating apparatus as described above, wherein the apparatus includes attachment means compatible with a plumbing fixture.

In yet another related aspect the invention provides a locating apparatus as described above, wherein the apparatus includes attachment means compatible with a connecting device.

In a further broad aspect the invention provides a flush box (or a functional equivalent) having an ultimately detachable indication means (or locating pin) capable of penetrating or passing through a wall panel applied over the flush box, so that the position of the flush box behind the wall panel is substantially evident after the wall panel has been applied and so that the flush box can later be revealed.

Optionally the invention can be applied to any structure built inside a surface of a building, which structure is temporarily covered by cladding or panelling, and which structure can be marked by a penetrating locator means. Structures include but are not limited to services such as electricity, gas, or water fittings; range hood fittings, tumble dryer fittings, or even studs and dwangs themselves.

In another aspect the invention provides a detachable indication means capable of being temporarily attached to a flush box (or the like) during wall covering procedures. In a related aspect the preferred indication means presents a sharp point capable of penetrating through the wall panel after the wall panel has been applied over the flush box.

In a further related aspect the preferred indication means is preferably made of a hardened metallic material.

In a still further related aspect the preferred indication means can preferably be detached from the flush box after the flush box has been revealed.

Optionally the preferred indication means can be unscrewed from a threaded hole.

Alternatively the preferred indication means has a base susceptible to breakage so that it can be bent over and detached by metal fatigue or the like.

Alternatively the preferred indication means has a frangible base and a second sharp point so that it can be hammered into an underlying wooden support.

In another aspect the invention provides a method for constructing a building including the steps of locating the positions of at least one flush box on a surface, the method including the steps of mounting the preferred location means on each flush box, preferably in a standard position, then mounting a panel onto the surface including the at least one flush box, pressing the panel over the at least one preferred location means so that the point of each location means becomes evident, marking out the outline of the entire flush box using the point of each location means as a reference point, excavating the panel so as to expose each flush box, and removing the location means from the flush box.

DRAWINGS

The following is a description of a preferred form of the invention, given by way of example only, with reference to the accompanying diagrams.

Fig I: is an illustration of flush boxes with locator pins.

Fig 2: is an illustration of three versions of the locator pins of the present invention.

Fig 3: is a section through a wall wim a flagged flush box.

Fig 4: is a section through a wall, after completion of electrical installation.

PREFERRED EMBODIMENT

This preferred embodiment particularly relates to electrician's flush boxes (open-faced boxes inside which electric outlets and/or electric switches and the like) are held. A flush box is generally attached along one side to a vertical or horizontal member (studs or dwangs) of wall framing at a position such that its open face is approximately in the same plane as the rear surface of a wall panel, wires are fed into it, and after the panel is mounted the flush box is exposed, the wires are brought out, and connections are made to the electrical equipment involved. However plumbing connections, TV aerial connections, telephone connections, central vacuum cleaner outlets and the like may be mounted within a wall prior to application of wall panels. As mentioned previously, it is not difficult to lose the position of an outlet once the panel is in place and even if measurements were made, the reference position may be lost during the building procedure.

Our preferred type of locating means is a locating pin which is a pin-like metal rod having a sharp point at one end (or otherwise prepared so as to penetrate the wall panel without general damage to it) and fixing means at the other end so that it can be supported in a robust manner by the flush plate itself, perhaps by the flush plate in conjunction with the adjacent stud or dwang. When the wall panel has been placed the position of each flush box (or like fixture to be exposed) is indicated by the exposed sharp points. After location, the sharp point is generally removed for re-use and the hole it made is generally at the edge of a hole later made through the panel for the purpose of accessing the service provided within. All that the tradesman has to do is, assuming that he has a policy of always having the locating means at the top of the flush box or other fixture, cut around an appropriate template positioned so that the tip of the locating means passes through an upper part of the template. Then the locating means can be removed, electrical devices placed in the box, and a switch plate or the like applied to cover the hole through the panel.

A flush box 102 made according to this invention may be sold with an already installed locating pin 101 , or may be provided with means capable of reversibly holding a locating pin which (for example, if the locating pin is threaded) may comprise a threaded hole.

Referring to the Figures, Fig 1 shows a perspective view of a first preferred type of flush box 100, having an attached pin 101 protruding outward (in the same direction as the opening 103) from one of the facing strips generally provided across opposite ends of a flush box. This flush box has been modified by the provision of an extra aperture 106 to receive the locator pin; this aperture is preferably threaded in order to accommodate the threads (204) provided in our preferred locator pins. All the installer needs to remember is to attach each flush box with the extra aperture 106 along the top. Then, when locating the position of flush boxes, one simply suspends a template or another flush box from its corresponding aperture and draws the outline of the hidden flush box onto the panel, as a guide to cutting.

At the right of Fig 1 is another way to construct a flush box 104 (seen from the open face). In this instance the locator pin 105 is put in one corner in order to make use of the added strength to be found at any corner. Flush boxes may be made out of cast metal, pressed metal, folded and welded metal, or a plastics material, and some of them may be deliberately made with an intrinsically weak section for shearing off, for this kind of additional function. Fig 2 shows some example locator pins 200. The top example is a simple 4 mm diameter steel pin of about 22-25 mm in length with a sharp end (or at least an end adapted to penetrate the expected kind(s) of wall panels in current use) and an end adapted for affixing to the flush box in the manner shown in Fig 1. A machine screw thread is one option, (4 mm diameter is about 1 mm pitch although a coarser thread may be better for use with plastics materials); a self-tapping thread is another option, or some other kind of preferably removable attachment may be used instead. Another possibility is to provide the locator pin with sharp points at both ends, and hammer the locator pin into an underlying stud or dwang after the flush box has been exposed. A steel flush box could be manufactured with a spot- welded, sharp-tipped finger of steel attached; this could be bent out from its base at 90 degrees for use and later bent several times in order to break it off.

Clearly, one can sell flush boxes each packed with a fitted, or an accompanying locator pin, or one can sell locator pins as a separate commodity and the electrician (or plumber, etc) can drill and tap holes in any object to be mounted as and when necessary. Even if they are re-usable it is likely that an electrician would need at least 50 pins in order to simultaneously use one pin per electrical outlet in a typical new home. (By "simultaneously" we mean the practice wherein an electrician comes to a site, fits and wires all the flush boxes (each having its locator pin), and departs until the workmen responsible for wall panelling have finished their work.

In order to increase the stiffness of a mounted locator pin we offer a skirt or stiff washer 203 which abuts with the flush box surface and reduces torsion on the threads.

Our preferred material is a hardened steel, and we have used concrete nails as prototypes, though this may be optimised in practice. In a related aspect the preferred indication means presents a sharp point capable of penetrating through the wall panel after the wall panel has been applied over the flush box.

A preferred type of locator pin is shown approximately to scale as the lowest item 206 in Fig 2. This pin is made of plated steel. The example is 26 mm in length (though longer pins may be preferred), 4 mm in diameter along the shank 209, and the tapered portion is 10 mm long to reach the point 207. The thread 208, which is 8 mm long, has a 6/32 UNC thread because that thread is standard for the captive nuts provided in flush boxes used in New Zealand. We prefer a longer taper and a more abrupt taper at the point. The pin is intended for re-use. The nut is then used for the (often concealed) screws that hold the flush plate on to the open face of the flush box. Plated steel is preferred because of the possibility of bare steel leaving iron fragments on a wall surface that may later rust.

A method for constructing a building and employing this invention in order to locate the position of at least one flush box on a surface may involve the steps of:-

( 1 ) assembling flush boxes in desired positions and wiring them as usual,

(2) mounting the preferred location means on each flush box (and because the location means is generally a sharp point it may be wise to leave this until a late stage in wall preparation), (3) (preferably each locating pin is in a standard position)

(4) mounting a panel onto the surface so that the flush box or boxes are concealed, pressing (or perhaps hammering) the panel over the locating pins so that the point of each pin becomes evident,

(5) marking out the outline of the entire flush box using the exposed point of each location means as a reference point,

(6) excavating the panel so as to expose each flush box, and

(7) removing the location means from each flush box.

Whereas it used to be standard practice to leave the unconnected wires training from the front of the flush box before panel application, it is now possible for the wires to be returned to the wall space through another aperture in the flush box, and then hook the wires out when installing electrical apparatus.

Then the usual things can be done to the flush box - completion of electrical installations, attaching covers, etc.

Fig 3 shows at 300 a flush box 100 concealed behind a wall panel 301, except for a locator pin 101 protruding through the panel. (Typical "Gibraltar Board" panels (made of plater inside paper skins) are 9.5 mm thick). Fig 4 shows at 400 a later stage in the process. Now there is an opening 401 cut through the panel precisely over the site of the flush box, and a switch (or the like) cover 402 is in place over the opening. Note that the locator pin should be ultimately detachable and so fig 4 shows no locator pin.

The locator pin identifies a companion flush box by its position. The installer generally will put the locating pin in a standard position in relation to the concealed flush box, for example it might always be in the top centre, or it might always be at the lower left. If placed in a corner, it will be more strongly supported than if it is on the top centre, on an edge. (Flush boxes, like many other components, are no stronger than they need to be). The strongest corner support is against a stud. There may then need to be some convention as to whether the flush box goes on the left of a stud or the right of a stud. Indication means capable of passing through a wall panel applied over the flush box, so that the position of the flush box behind the wall panel is substantially evident after the wall panel has been applied and so that the flush box can later be revealed.

Alternatively the preferred indication means has a frangible base and a second sharp point so that it can be hammered into an underlying wooden support. Preferred method of use:

1. Fix flush box in desired position.

2. Screw locating pin into upper screw hole of flush box

3. Press wall panel against studs, allowing locating pin to penetrate through board

4. Tack wall panel securely into place

5. Place template over locating pin, and mark border of desired hole.

6. Cut out the hole, e.g. with a pad saw, and remove the locating pin.

ADVANTAGES

Effective use of the locating pin of this invention will result in the following user benefits:

(1) Time is saved by avoiding the need to pre-measure and cut the wall panel (e.g. Gibraltar board) prior to, or after fixing it onto a wall.

(2) Avoiding mistakes and damage which can result from measurement. Quite often, cuts made in a panel prior to mounting result in weakness and breakage, because they are often near an edge.

(3) Providing the precise location of all flush boxes (or the like) fitted with flush pins, so that none are lost and forgotten. Usually, some flush boxes are lost inside walls, despite having been installed and connected with electrical wiring.

INDUSTRIAL APPLICATION

The invention is a tool for use in construction. It can be applied on any new building in which panels are affixed to surfaces, and where the surfaces have previously been provided with structures such as flush boxes which before use can be made of them have to be exposed to the surface through holes cut in the panel. The invention saves money by speeding up panel fixing, and minimising damage to the panels, particularly that damage caused by searching for lost flush boxes or large holes made for flush boxes which were not quite in the right place. It saves in human resources by not requiring that measurements be taken, recorded, and later re-mapped onto the wall panels.

VARIATIONS

While this invention particularly relates to flush boxes as used by electricians, it may also be applied to other fittings installed in the wall (or even the floor or ceiling) of a building. For example it might be used with plumber's fittings such as tap mounts. It might be used to help locate gas outlets, air conditioning ducts or built-in vacuum lines from a vacuum cleaner installation.

In some situations in some countries, electrical apparatus may not be contained within a box but simply held against a stud on a "C" plate, and eventually, when a switch plate is attached on the front of the wall panel, it is essentially held onto the panel. A variation on the invention as described above, therefore, is a plate of this type. In effect this kind of plate is a metal strip usually with a bend, so that some (a first part) of the strip goes over the face of a stud or dwang, and a second part goes down a side. These plates are also liable to be lost during assembly of a wall. Again, opportunities for placement of a locator pin exist. For example it may be welded or otherwise attached on the second part of the C plate, or attached over the first part. Here, one of the locator pins that can be hammered down into the stud once it has served its primary purpose can be used.

Although floor panels are generally to solid and dense for use with locating pins of this invention as they are currently understood, the principle may be adapted.

Finally, it will be appreciated that various alterations and modifications may be made to the foregoing without departing from the scope of this invention as set forth.

Claims

CLAIMS:

1. A method for construction comprising placement of a surface covering panel on a framework; the surface being laid over one or more devices held beneath the surface; where there is a requirement to expose at least a portion of the or each device by forming an overlying aperture through the surface, the method comprising:-

(a) installation on the or each device of locating apparatus capable of penetrating the surface covering panel,

(b) installation of the or each device on a framework ,

(c) fastening a surface covering panel in place, so that the locating apparatus installed on the or each device deforms or penetrates the covering panel,

(d) noting the position of the or each locating apparatus and forming an aperture through the covering panel in a defined relationship to the or each locating panel.

2. Locating apparatus for use during construction or renovations of a building; the locating apparatus being capable of indicating the position of a device concealed within a surface, characterised in that the locating apparatus comprises an elongated member having a first end capable of penetrating a covering panel, the member having detachable attachment means at a second end, and the member having sufficient length to provide for attachment to a structure and also to penetrate through the covering panel subsequently attached to the surface, the position of the rod thereby indicating the position of the now concealed device.

A device intended to be concealed within a surface of a building, characterised in that the device is made to include at least one locating apparatus as claimed in claim 2.

4. Locating apparatus as claimed in claim 2, characterised in that the locating apparatus is made of a tough metal material.

5. Locating apparatus as claimed in claim 4, characterised in that the locating apparatus has a point at the first end.

6. Locating apparatus as claimed in claim 4, characterised in that the detachable attachment means of the locating apparatus comprises a screw thread.

7. Locating apparatus as claimed in claim 2, characterised in that the locating apparatus is made of a tough plastics material.

8. Locating apparatus as claimed in claim 2, characterised in that the detachable attachment means of the rod comprises a weakened frangible zone capable of being broken off after use.

9. Locating apparatus as claimed in claim 2, characterised in that the apparatus includes attachment means compatible with an electrical flush box.