GB2464205A

GB2464205A - Machining-Monitoring Device and Illumination Unit

Info

Publication number: GB2464205A
Application number: GB0917487A
Authority: GB
Inventors: Jan Koegel
Original assignee: Robert Bosch GmbH
Current assignee: Robert Bosch GmbH
Priority date: 2008-10-08
Filing date: 2009-10-06
Publication date: 2010-04-14
Anticipated expiration: 2029-10-06
Also published as: GB0917487D0; CN101716694A; DE102008042687A1; GB2464205B

Abstract

A power tool is provided with a machining-monitoring device 6 for monitoring the workpiece to be machined, comprising a monitoring plate 7 extending in the machining direction and an illuminating unit 8 arranged on the monitoring plate. The power tool is preferably hand held for example a saw. The plate may have a scale 13 on one side and may have a reflective coating on one side or may be transparent to direct light from the illumination unit towards the workpiece. The illumination unit may be a light emitting diode (LED) or lamp 9, 10 powered by a battery 14 or accumulator, or via the tool and mirrors may redirect the light. The light may be visible light or ultra-violet (UV) light. The machining-monitoring device may be attached to the base plate 5 of the power tool such that it rests on the workpiece during machining (figure 1), and may be removable.

Description

Description Title

Power tool, in particular hand-held power tool The invention relates to a power tool, in particular a hand-held power tool, such as, for example, a cutting or sawing power tool.

Prior art

A universal saw, which is usable as a jigsaw or sabre saw and the saw blade of which is driven by an electric drive motor, is known from DE 10 2005 025 280 Al. Arranged in the bottom region is a base plate which is to be connected to the housing of the universal saw, rests on the workpiece during the machining and serves for guidance of the universal saw. In the base plate there is made an opening, through which the saw blade is passed for machining the workpiece. The base plate can be rigidly locked on the housing of the universal saw in a defined working position in which the plane of the base plate is perpendicular to the direction of the working movement of the saw blade, it being possible to set further working positions with a variable angular position of the base plate.

Disclosure of the invention

Starting from this prior art, the object on which the invention is based is to improve the accuracy during the machining of a workpiece using a power tool by simple means.

This object is achieved according to the invention by the features of Claim 1. The subclaims specify expedient developments.

The power tool according to the invention is preferably a hand-held power tool, in particular an electric hand-held power tool, such as a jigsaw or hand-held circular saw, although in principle hand-held power tools with other drives are also possible in the context of the invention, and optionally also stationarily arranged power tools.

The power tool is provided with a machining-monitoring device which has the function of enabling monitoring of the workpiece during the machining. For this purpose, the machining-monitoring device has a monitoring plate extending in the machining direction and an illuminating unit arranged on the monitoring plate. It is thus possible for different functions to be combined and for additional tasks to be performed by the machining-monitoring device.

On the one hand, the machining direction can be monitored with the aid of the machining-monitoring device, in particular the monitoring plate. Optionally, additional guidance of the power tool by means of the monitoring plate is also possible. On the other hand, the illuminating unit serves for illuminating the working area and the monitoring plate, so that optimal light conditions are provided for the machining of the workpiece, irrespective of the external light conditions. The illumination here extends in particular to the working area in which the tool of the power tool is machining the workpiece, and also to the monitoring plate, which can thus likewise be better seen and read by the operator. Along an edge of the monitoring plate, it is possible, for example, to provide a scale which is illuminated by the illuminating unit.

According to a preferred embodiment, it is provided that a light beam emitted by the illuminating unit or a light wave is guided via the monitoring plate to the working region.

In this configuration, the monitoring plate serves as a medium conducting the light beam which is guided along the surface of the monitoring plate and/or through the interior of the monitoring plate. In the case of light conduction over the surface, the latter can be provided with a special coating promoting the light conduction, or the monitoring plate can be produced from such a material, both complete covering of the surface of the monitoring plate with the light-conducting material and only partial covering being possible, for example in the form of light-conducting paths in the direction of the edge of the monitoring plate or the working area to be illuminated. In the case of light conduction through the interior of the monitoring plate, the latter preferably consists of a transparent material, the monitoring plate expediently ensuring light scattering, so that a light beam emerging from an illuminating means of the illuminating unit can be spread out and for example a diffusely illuminated working area can be established. In principle, however, localised illumination, for example in a very confined region around the tool of the power tool is also possible, or a hybrid form in which, in addition to localised, confined illumination of the working area with high light intensity in the immediate vicinity of the tool, diffuse illumination with lower light intensity in the wider surrounding area of the tool is also achieved.

Furthermore, it. is possible for example to illuminate the scale and/or the edge ofthe monitoring plate with higher light intensity in order to indicate the machining distance and the machining direction more precisely.

The edge of the monitoring plate preferably also serves as a refracting edge for the light, in particular in the embodiment in which a light beam or a plurality of light beams are conducted through the interior of the monitoring plate. The refraction of the light beam at the edge results on the one hand in improved visibility of the edge per se and on the other hand in deflection of the light beam in the direction of the working area.

Various types or kinds of light can be used as the light source of the illuminating unit. In a preferred embodiment, it is provided that at least one light source of the illuminating unit is in the form of an LED (Light Emitting Diode). Furthermore,it is both possible to emit only a single light beam of a light source, which light beam is optionally refracted or scattered, and a plurality of light beams which emerge, via technical devices such as mirrors or the like, either from a single light source or else from a plurality of light sources arranged on the machining-monitoring device. A plurality of light beams have the advantage that a larger working area can be illuminated, that different sections of the monitoring plate can be illuminated and/or that the illumination is carried out with higher light intensity. According to a preferred embodiment, it is'provided that the light beams extend at an angle to one another, although in principle a parallel course of a plurality of light beams along the surface of the monitoring plate or in the interior of the monitoring plate is also possible.

The supply of pàwer to the illuminating unit in the machining-monitoring device is preferably effected via a battery or an accumulator, which is to be replaceably inserted in an associated compartment in a housing on the machining-monitoring device. Furthermore, a switch is provided on the hOusing on the machining-monitoring device for switching the illuminating unit on and off.

According to an alternative embodiment, the power supply is effected via the power tool. In this case, when the machining-monitoring device is connected, electrical contact is established between the illuminating unit and an eleôtrical supply unit of the power tool, the illuminating unit being switched on and off either via a switch on the machining-monitoring device or, according to a further alterhative embodiment, via a switch on the power tool. The electrical connection between the illuminating unit on the machining-monitoring device and the power tool is preferably effected via electrical contact points which are provided.both on the machining-monitoring device and in a manner corresponding thereto on the power tool, so that the electrical contact is automatically established when the machining-monitoring device is fastened to the power tool.

The machining-monitoring device can be fastened, for example, to a base plate of the power tool. This embodiment is suitable in particular for universal saws, such as, for example, jigsaws, provided with such a base plate. In principle,however, a detachable fastening to the housing of the powertool is also possible.

Preferably, light beams with a wavelength in the visible range are emitted via the illuminating unit. It is, however, also possible, alternatively or additionally, to emit waves in the invisible range, for example ultraviolet light, which is transported by the monitoring plate as a light conductor. UV-light may optionally be used to control actions or detect obstacles.

Further advantages and expedient embodiments can be gathered from the further claims, the description of the figures, and the drawings, in which: Fig. 1, shows an illustration of an electric-motor-driven hand-held power tool in the form of a jigsaw during the machining of a workpiece, with a machining-monitoring device, which has a monitoring plate and an illuminating unit, being arranged on a base plate of the jigsaw, Fig. 2 shows the machining-monitoring device having the monitoring plate and the illuminating unit in an enlarged individual illustration, Fig. 3 shows the machining-monitoring device connected to the base plate of the power tool in an enlarged illustration.

In the figures, identical components are provided with the same reference symbols.

Illustrated in Fig. 1 is an electric-motor-driven hand-held power tool 1 in the form of a jigsaw which has, in a housing 2, the electric drive motor for driving the tool in the form of a saw blade 3. For machining a workpiece 4, there is arranged on the lower side of the housing 2 of the hand-held power tool 1 a base plate 5 which, during the machining, rests on the upper side of the workpiece 4 and ensures level guidance of the hand-held power tool on the Furthermore, the hand-held power tool 1 is equipped with a machining-monitoring device 6 which comprises a monitoring plate 7 and an illuminating unit 8 and which has the task of enabling more precise machining of the workpiece and also better illumination of the working area in the vicinity of the tool 3. The monitoring plate 7 of the machining-monitoring device 6 is situated in front of the base plate 5 when seen in the machining direction and, like the base plate 5, rests on the upper side of the workpiece 4 to be machined. The lower sides of base plate 5 and monitoring plate 7 thus lie in a common plane. The illuminating unit 8 is located on the side of the machining plate 7 direätedtowards the base plate 5 in the immediate vicinity of the tool 3.

As can be gathered from Fig. 2, the illuminating unit 8 is accommodated on the upper side of the monitoring plate 7.

Both embodiments in which the illuminating unit 8 is designed as a unit which is formed separately from the monitoring plat 7 and is to be connected to the monitoring plate 7 and an integral or one-piece design of monitoring plate 7 and illuminating unit 8 are possible here.

The illuminating unit 8 accommodates lamps 9 and 10 which form light sources and emit light beams 11 along the monitoring plate 7. The lamps 9 and 10 in the illuminating unit 8 are situated at a distance from an edge 12 of the monitoring plate 7 extending along the machining direction of the tool of the hand-held power tool. The light beams 11 may be arranged at an angle to one another, so that the different light beams 11 as a whole illuminate a relatively large angular section along the upper side of the monitoring plate 7 in the direction of the edge 12.

The monitoring plate 7 preferably consists of a transparent material, in particular a partially or completely transparent plastic, the material of the monitoring plate 7 allowing light conduction, and to be precise preferably both at the upper side and through the material of the monitoring plate in the direction of the edge 12, which at the same time forms a refracting edge for refracting the light beams in the direction of the workpiece located therebelow. The material of the monitoring plate 7 also causes diffuse spreading of the light, whereby evening-out of the light spreading and of the illumination of the working area is achieved. However, by various light-conducting measures, it may be expedient optionally also to produce localised irradiation especially of the working area in the immediate vicinity of the tool.

A scale 13 is situated on the upper side of the monitoring plate 7 adjacent to the edge 12 and extending in the longitudinal direction of the edge 12. The scale 13 is also illuminated by the light beams 11 emerging from the illuminating unit 8.

The illuminatingunit 8 comprises a housing for accommodating the lamps 9and 10, and integrated in the housing of the illuminating unit 8 is additionally a battery compartment 14 which serves to accommodate replaceable batteries for supplying power to the lamps 9 and 10. Situated on the upper side of the housing of the illuminating unit 8 is additionally a switch 15 for switching the lamps 9 and 10 on and off. Additionally, a lever 16 which serves for opening and closing the battery compartment 14 projects above the upper side of the housing of the illuminating unit 8.

As can be gathered from Fig. 2 in conjunction with Fig. 3, a triangular or trapezoidal indentation 17 is made in the monitoring plate 7 on the side facing the base plate 5, with which indentation there is associated in the base plate 5 a section of complementary form for accommodating and connecting the monitoring plate 7 on and to the base plate 5. The monitoring plate 7 including the illuminating unit 8 arranged thereon is detachably connected to the base plate 5 via suitable connecting devices such as clamps, screws or the like.

An opening 18 for the tool 3 of the power tool is made in the base plate 5. When the machining-monitoring device 6 is mounted, the opening 18 lies in line with an extension of the edge 12 of the monitoring plate 7.

Claims

Claims 1. Power tool, in particular hand-held power tool, such as, for example, cutting or sawing power tool, having a machining-monitoring device (6) on the power tool (1) for monitoring the workpiece (4) to be machined, the machining-monitoring device (6) having a monitoring plate (7) extending in the machining direction and an illuminating unit (8) arranged on or at the monitoring plate (7).
2. Power tool according to Claim 1, characterised in that a light beam (11) emitted by the illuminating unit (8) is guided by the monitoring plate (7) to the working region.
3. Power tool according to Claim 1 or 2, characterised in that the light beam (11) is guided over the surface of the mOnitoring plate (7).
4. Power tool according to one of Claims 1 to 3, characterised in that the light beam (11) is guided through the monitoring'plate (7) or is conducted through the material layer of the monitoring plate (7).
5. Powertool according to one of Claims 1 to 4, characterised in that the monitoring plate (7) consists of a transparent material.
6. Power tool according to one of Claims 1 to 5, characterised in that the illuminating unit (8) has a plurality oflight sources (9, 10).
7. Power tool according to one of Claims 1 to 6, characterised in that the at least one light source (9, 10) of the illuminating unit (8) is in the form of an LED.
8. Power tool according to one of Claims 1 to 7, characterised in that a plurality of light beams (11) at an angle to one another emerge from the illuminating unit (8).
9. Power tool according to one of Claims 1 to 8, characterised in that the monitoring plate (7) has a scale (13), illuminated by the light beam (11), along a machining edge (12).
10. Power tool according to one of Claims 1 to 9, characterised in that the machining-monitoring device (6) is to be detachably fastened to a base plate (5) of the power tool (1).
11. Power tool according to one of Claims 1 to 10, characterised in that the machining-monitoring device (6) is to be detachably fastened to a housing of the power tool (1).
12. Machining-monitoring device for a power tool, in particular for a hand-held power tool (1), such as, for example, a cutting or sawing power tool, preferably for a power tool according to one of Claims 1 to 11, the machining-monitoring device (6) having a monitoring plate (7) extending in the machining direction and an illuminating unit (8) arranged on the monitoring plate (7).
13. A power tool substantially as herein described with reference to the accompanying drawings.
14. A machine-monitoring device substantially as herein described with reference to the accompanying drawings.