GB2598901A - Depth control for drilling - Google Patents

Abstract

A system for use in drilling a hole includes a unitary component 10 with a mounting portion 12 of planar material, and loop formations 30. Each loop formation 30’ is interconnected by severable connecting elements 40, 42 to one or more other loop formations or to the mounting portion. Each loop formation may be a ring of circular cross-section. The connecting elements may be frangible and may include a line of weakness to promote fracture of the connecting element. The unitary component may be a one-piece moulding formed of a resilient plastic material. The loop formations may be of a bright or distinctive colour. Instructions for use 46 may be formed on the unitary component by surface marking. The system is used in a method of drilling a hole to a required depth by selecting a drill bit of the required diameter, detaching one loop formation that corresponds to the size of drill bit by severing one or more connecting elements, positioning the loop onto the shank of the drill bit at a distance from the drill tip at the required depth, and drilling until the loop formation is at a point of making contact with a surface.

Description

Depth Control for Drilling This invention relates to a system to enable depth control when drilling.

There are many applications in which a twist drill is used to drill a hole to a specified depth. For example, there may be a requirement for a hole to be a minimum depth to accommodate an item such as a wall plug, or a maximum depth to avoid damage to or weakening of an object that is being drilled. Depth control can be achieved easily using a pillar dill, it is not always possible to use such a tool; for example, when drilling into a wall, a hand-held drill is normally required.

Some hand-held drills are provided with an adjustable depth guide that comes into contact with a body being drilled into to limit the depth of a hole being drilled. However, these can be difficult to set accurately, and may not be usable when a hole is 15 being drilled in a confined space.

Some workers will wrap a length of adhesive tape around the shank of a drill bit to indicate the limit of the shank that should be contained within a hole being drilled. However, it can be difficult to position the tape accurately, and since the tape is tight against the shank, it often happens that the exact position of the tape is difficult to judge as it becomes obscured by chip material ejected from the hole.

An aim of this invention is to provide a simple and effective system by which the depth of a drilled hole can be controlled.

From a first aspect, this invention provides a system for use in drilling a hole comprising a unitary component, the unitary component including a mounting portion of planar material and a plurality of loop formations, each loop formation being interconnected by severable connecting elements to one or more other loop formation or to the mounting portion.

In a typical embodiment, each loop formation is a ring of generally circular cross-5 section. Each loop formation is typically disposed in the plane of the mounting portion.

The connecting elements may be frangible, and each may include a line of weakness to promote fracture of the connecting element Alternatively, the connecting elements may be severable by cutting.

The unitary component is typically a one-piece moulding. It is preferably made of a 10 resilient plastic material. At least the loop formations are preferably of a bright or distinctive colour.

A system embodying the invention preferably includes instructions for use of the loop formations in a drilling operation. The instructions may be formed directly on the unitary component, such as by surface marking or by direct inclusion in the moulding.

Alternatively or additionally, the system may further include a product package upon which the instructions are displayed.

The mounting portion preferably includes formations, such as one or more apertures, suitable for co-operation with a retail display system.

From a second aspect, this invention provides a method for drilling a hole in a body to 20 a required depth comprising: -selecting a drill bit suitable for making a hole of the required diameter and depth; -from a moulded component that includes a plurality of variously-sized, loop formations interconnected by severable connecting elements, detaching one loop formation by severing one or more connecting element, which loop formation is of a size that corresponds to the side of the selected drill bit; passing the drill bit through the loop formation onto a body or shank of the drill bit, the drill bit causing elastic deformation of the loop component, the loop component being positioned on the drill bit at a distance from a tip of the drill bit determined by the required depth; and -using the drill bit to drill into the body until the loop formation is at the point of making contact with the body.

In a method embodying the invention, each loop formation may be a circular ring.

An embodiment of the invention will now be described in detail, by way of example, and with reference to the accompanying drawings, in which: Figure 1 is a front view of a moulding being a component of an embodiment of the invention; Figure 2 is a rear view of the moulding being a component of Figure 1; Figure 3 is a front view of the component of Figures land 2 in retail packaging; and Figure 4 is a rear view of the retail packaging of Figure 3.

With reference to the drawings, an example of a product is shown that enables depth control during drilling using a hand-held powered drill and a twist drill bit.

The product includes a unitary moulded component 10, as shown in Figure 1. The 20 moulded component, in this example, is planar and has a thickness of approximately 1.8mm. It is symmetrical about a median plane that extends parallel to the plane of the figures.

The moulded component 10 includes a hanging portion 12 shaped as a right trapezium with an overall width of 60mm. The hanging portion has a top edge 14 and side edges 16, 18 that extend at right angles from the top edge 14, the top and side edges being interconnected by rounded corners. A hanging hole 20 extends through the hanging portion 12, being shaped and dimensioned to cooperate with a retail hanging display system.

The moulded component 10 further includes a portion formed by a plurality of loop formations in the form of moulded rings, shown generally at 30 and individual examples at 30'. In this embodiment, the moulded rings are arranged in first, second and third rows 32, 34, 36, each row including six rings of four different sizes. The rings are formed with inner diameters selected such that they are a tight sliding fit on a range of different, common drill sizes (e.g., 3.5, 5, 7 and 10mm). One size of ring 30' may find application for use on a range of drill sizes.

The moulded component further includes multiple interconnecting elements. A first set of connecting elements 40 (just two being labelled) connects a respective one ring in the first row 32 to the hanging portion 12. Further connecting elements 42 (examples being labelled) interconnect adjacent rings in the same and neighbouring rows 32, 34, 36. Thus, each ring is connected to 2, 3 or 4 connecting elements 40. The connecting elements 40, 42 are formed to be weaker than the ring, either simply by virtue of their being thin, or by moulding a region of weakness (for example, a line crossing the connecting element in which the section is thin) into each of them. This allows a single ring 30' to be detached from the moulded component 10 either by causing facture of the connecting elements 40, 42 to which it is connected (e.g., by manually twisting it) or by cutting the connecting elements 40, 42 using a tool.

It will be seen that in this preferred arrangement, any two rings 30' in adjacent rows 32, 34, 36 that are interconnected are of the same size as one another (although within a row, rings of different sizes are interconnected). This means that it is never necessary to detach more than one ring 30' in order to obtain a ring of a required size.

To drill a hole of a specified depth in a body with the aid of the invention, a user first selects a suitable drill bit for the size of hole required, with a diameter within a working range of the system [1]. A drill bit typically has a fluted body that extends from a shank to a cutting head, the cutting head having a point coaxial with the shank.

The next step is to determine an appropriate size of ring 30'. The ring 30' should be of a size that it can fit over the cutting head of the drill bit onto the fluted body with some elastic extension to place the material of the material of the ring 30' under sufficient tension to grip the flute or the shank of the drill bit and resist movement of the ring 30' on the drill bit. Once the correct size has been determined, an appropriately sized ring 30' is detached from the moulded component 10' as discussed above [2].

The user must then determine the correct axial position of the ring 30' on the shank of the drill bit [3]. If it is a requirement that the depth dm of the hole must not exceed a maximum (for example, to avoid causing damage) the ring 30' is placed on the fluted body or the shank at a position such that the distance measured from the point to the ring 30', in a direction parallel to the shank, does not exceed timax. This measurement is shown pictographically on the hanging portion 12 at 46. If a minimum depth of hole dinin is required (for example, to accommodate a wall plug) , the ring 30' must be placed on the fluted body or the shank at a position such that the distance measured from the point to the ring 30', in a direction parallel to the shank, is marginally greater than dmin.

Note that the ring 30' may be positioned either on the fluted body or on the shank, depending upon the depth of the hole and the length of the drill bit.

The hole is then made by using a drill to drive the drill bit into the body until the ring just makes contact with the body [4], further drilling is stopped [5] and the drill bit can be withdrawn from the hole. At this point, a hole of the correct depth will have been formed [6]. It is important not to keep drilling once the ring 30' comes into contact with the body, since this will cause the ring 30' to move along the shank, resulting in a hole of excessive depth.

The material from which the moulded component 10 is formed is a semi-rigid plastic with some elasticity. In particular, it should have sufficiently resilient to allow a ring 30' detached from it to be deformed sufficiently when placed on a drill bit as discussed above. It is also preferable that the material from which the moulded component 10 is formed is brightly and/or distinctively coloured, so that its position relative to the body can be clearly seen while a hole is being drilled.

The moulded component could be sold on its own as a product or it could be packaged, for example as shown in Figures 3 and 4. This example packaging comprises a folded card cover that has generally rectangular front and rear panels 50, 52 interconnected at a fold line 54. When installed in the packaging, a top edge of the moulded component 10 extends parallel to and immediately adjacent to the fold line 54.

A respective hanging aperture 56, 56' is formed through each of the front and rear panels 50, 52. The hanging apertures 56, 56' are shaped and dimensioned so as to closely conform with and lie adjacent to (but on opposite sides of) the hanging hole 20 of the moulded component contained in the packaging, thereby allowing the packaged product to be displayed for sale on a suitable retail hanging display system. A respective display cut-out 60, 60' is formed into one edge of each of the front and rear panels 50, 52. The display cut-outs 60, 60' are adjacent to one another opposite sides of the packaged moulded component 10, whereby a portion of the moulded component 10 is visible through the display cut-outs 60, 60'.

The packaging serves to protect the moulded component 10 from damage and also is functional in that it contains primarily pictorial directions for use of the system. In this example, images 1 to 6 on the rear panel correspond to the sequence numbers in square brackets in the description above.

Claims (16)

1. Claims 1. A system for use in drilling a hole comprising a unitary component, the unitary component including a mounting portion of planar material and a plurality of loop formations, each loop formation being interconnected by severable connecting elements to one or more other loop formation or to the mounting portion.
2. 2. A system according to claim 1 in which each loop formation is a ring of generally circular cross-section.
3. 3. A system according to claim 1 or claim 2 in which each loop formation is disposed in the plane of the mounting portion.
4. 4. A system according to any preceding claim in which connecting elements are frangible.
5. 5. A system according to claim 4 in which each connecting element includes a line of weakness to promote fracture of the connecting element
6. 6. A system according to any preceding claim in which the connecting elements are severable by cutting.
7. 7. A system according to any preceding claim in which the unitary component is a one-piece moulding.
8. 8. A system according to any preceding claim in which the unitary component is formed of a resilient plastic material.
9. 9. A system according to any preceding claim in which the at least the loop formations are of a bright or distinctive colour.
10. 10.A system according to any preceding claim in that further includes instructions for use of the loop formations in a drilling operation.
11. 11.A system according to claim 10 in which the instructions are formed directly on the unitary component, such as by surface marking or by direct inclusion in a moulding.
12. 12.A system according to any preceding claim that further includes a product package upon which instructions for use of the loop formations in a drilling operation are displayed.
13. 13.A system according to any preceding claim in which the mounting portion includes formations, such as one or more apertures, suitable for co-operation with a retail display system.
14. 14.A method for drilling a hole in a body to a required depth comprising: a. selecting a drill bit suitable for making a hole of the required diameter and depth; b. from a moulded component that includes a plurality of variously-sized, loop formations interconnected by severable connecting elements, detaching one loop formation by severing one or more connecting element, which loop formation is of a size that corresponds to the side of the selected drill bit; c. passing the drill bit through the loop formation onto a body or shank of the drill bit, the drill bit causing elastic deformation of the loop component, the loop component being positioned on the drill bit at a distance from a tip of the drill bit determined by the required depth; and d. using the drill bit to drill into the body until the loop formation is at the point of making contact with the body.
15. 15.A method according to claim 14 in which each loop formation is a circular ring.
16. 16.A method according to claim 14 or claim 15 performed using a system according to any one of claims 1 to 15.