Background of the Invention A variety of hand-operated powered cutting tools are known and widely used. Tools of this type include, for example, jigsaws and circular saws. Before using such tools to cut a work piece, operators typically measure and mark cutting lines onto the workpiece to use a guide for cutting. Often, very precise cutting of the workpiece is required, and in these circumstances a guide line or marker is essential to ensure that the workpiece is properly cut. The operator often needs to make small cuts to determine whether the cut from the blade is aligned with the marked line on the workpiece. Several small cuts may be required before the blade is lined up correctly. This process is tedious and time consuming, and it can also result in wasted material.

It is therefore an object of the present invention to provide laser guidance for hand-operated power tools to assist an operator in cutting a workpiece.

Summary of the invention In a first aspect, the invention provides a laser generator for attachment to a hand-operated power tool, including: a housing assembly, including an aperture; laser means provided within the housing assembly; wherein, in use, the laser means emits a laser beam, the laser beam passing through the aperture in the housing assembly and projecting a laser guide onto a workpiece thereby assisting in guidance of the hand-operated power tool.

In a second aspect, the invention provides a hand-operated power tool, including: a tool body, the body having a front end; a cutting blade, located at the underside of the front end; a housing assembly, located at the front end and above the blade, including: an aperture in the housing assembly; laser means provided in the housing assembly; wherein, in use of the tool, the laser means emits a laser beam, the laser beam passing through the aperture in the housing assembly and projecting a laser guide onto a workpiece, the laser guide being projected in front of and aligned with the blade, thereby assisting in guidance of the tool to cut the workpiece.

Advantageously, the housing assembly further includes control means in the form of a printed circuit board, and battery means for supplying power to the printed circuit board. The printed circuit board is preferably electrically connected to the laser means.

The aperture is preferably formed at a front end of the housing assembly.

Advantageously, the orientation and shape of the aperture can be varied depending on the required use. In a preferred embodiment, the aperture is provided as a slit, such that a line of laser light is projected from the housing assembly. In alternate embodiments, the laser guide may be in the form of one or more dots, an arc, or other suitable shapes.

The housing assembly is preferably formed as a self-contained component that, in the first embodiment of the invention, may be attached to any suitable hand-operated power tool in which laser guidance would be useful. Alternatively, and in accordance with the second aspect of the invention, the housing assembly

is built in as part of a power tool. In the second aspect of the invention, the shape of the tool body can therefore be designed to accommodate the housing assembly in an integral manner.

The laser generator is suitable for use with any hand operated tool, and in particular for use with hand-operated power tools such as jigsaws, and circular saws. In the second aspect of the invention, the hand-operated power tool is preferably a jigsaw.

Brief Description of the Drawings The invention will now be described by way of example only, with reference to the accompanying drawings, in which; Figure 1 is a perspective view of the housing assembly in accordance with an embodiment of the invention; Figure 2 is a perspective view of the interior of the housing assembly of Figure 1, showing the battery, and laser means; Figure 3 is a side cross-sectional view of the assembly interior shown in Figure 2; Figure 4 is a perspective view of a circular saw with attached laser generator, in accordance with an embodiment of the invention; and Figure 5 is a perspective view of a jigsaw with a built-in laser generator according to a further embodiment of the invention.

Description of Preferred Embodiments Referring to Figures 1 to 3, there is illustrated the various components of a laser generator 10 in accordance with a preferred embodiment of the present invention. As shown in Figure 1, laser generator 10 includes a housing assembly 12, which has a front end 13, and rear end 15. The front end 13 of the housing

assembly 12 is provided with an aperture 14, through which a laser beam is able to pass.

Figures 2 and 3 show the interior components of the housing assembly 12.

Laser means 16 is provided which is electrically connected to a printed circuit board 18. Printed circuit board 18 is powered by batteries 20. The laser means 16, the printed circuit board 18 and a batteries 20 are all fastened to a mounting plate 22, and are adapted to fit within the housing assembly 12. Housing assembly 12 is adapted to be releasably securable to the mounting plate 22 to enable the batteries to be replaced as required. A battery cover 24 is provided in the housing assembly 12. When in use, the laser means emits a laser beam 26 through the aperture 14 and projects a line of laser light 28 onto the surface of a workpiece 30.

The laser generator 10 is configured to attach to a hand operated cutting tool, such as a circular saw 32 as shown in Figure 4. The circular saw is formed in a conventional manner. The line of light 28 projects directly in front and in line with the circular saw blade 34.

In further preferred embodiment of the invention, laser generator 110 is incorporated into a hand operated cutting tool, such as a jigsaw 132 as shown in Figure 5. The jigsaw 132 includes a body 136 and a cutting blade 134. A laser housing assembly 112 is located at the front 131 of the jigsaw 132 and above the cutting blade 134. The laser housing 112 is formed to provide an aperture 114.

The laser and battery means of this embodiment of the invention are provided in a similar manner to that described in relation to that shown in Figures 1-3. In this embodiment of the invention, the housing assembly 112 is directed downwardly, and the laser beam 128 is projected downwardly and immediately in front of the cutting blade 134 of the jigsaw.

It will be appreciated that, in one embodiment, the present invention provides a useful add-on attachment to hand-operated power tools that assists the operator in carefully aligning the cutting blade when cutting a workpiece. This

add-on laser generator offers the advantage that it be used in conjunction with existing power tools, and can be swapped between power tools as required.

The second embodiment of the invention provides a power tool having a built-in laser generator. This arrangement offers the advantage that is not necessary to attach and detach a laser generator, and ensures that the laser guidance beam is correctly aligned with the cutting blade at all times. Further, dust and dirt entrapment within the housing assembly is substantially avoided by having the laser housing assembly formed as an integral part of the power tool body.

It will be understood that the invention disclosed and defined in this specification extends to all alternative combinations of two or more of the individual features mentioned or evident from the text or drawings. All of these different combinations constitute various alternative aspects of the invention.