BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a first exemplary embodiment of an inventive hand-held power tool, in a side view.
FIG. 2 shows a section of the inventive hand-held power tool in FIG. 1, in the region of the tool fitting, in a perspective view.
FIG. 3 shows a schematic view of a printed circuit board with illuminating element, and a carrier with lens of the inventive hand-held power tool in FIG. 1.
FIG. 4 shows a second embodiment of an inventive hand-held power tool, in a perspective view.
FIG. 5 shows a section of the inventive hand-held power tool in FIG. 4, in a front view in accordance with the present invention.
FIG. 6 shows a first embodiment of an optical waveguide in accordance with the present invention.
FIG. 7 shows a second embodiment of an optical waveguide in accordance with the present invention.
FIG. 8 shows a third embodiment of an optical waveguide in accordance with the present invention.
FIG. 9 shows a further embodiment of an optical waveguide in accordance with the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
A rotary-impact wrench 100 is shown in FIG. 1, as an embodiment of an inventive hand-held power tool. Housing 10 is composed of two pieces, a motor housing 11 and a transmission housing 12. An on/off switch 14 is provided in the region of handle 13, with which an electric motor 17 (FIG. 4) is activatable. A tool fitting 15 for accommodating insertion tools, screw bits in particular, is located in the front—relative to the working direction—region of housing 10. Furthermore, the direction of radiation of light-emitting diodes is indicated in FIG. 1 via arrows 20. The light-emitting diodes are provided as illuminating elements 22 (FIG. 2) in the region of tool fitting 15. As indicated by arrows 20, illuminating elements 22 are located around the circumference of tool fitting 15.
FIG. 2 shows a section of the front—relative to the working direction—region of rotary-impact wrench 100 with transmission housing 12 and tool fitting 15. Transmission housing 12 is shown in a partial cross-section, in the perspective view in FIG. 2. An annular printed circuit board 21 is located around tool fitting 15, on the end face of transmission housing 12, on which several light-emitting diodes are installed, as illuminating elements 22. In the embodiment shown, these are light-emitting diodes without wire terminations (SMD light-emitting diodes) that are mounted directly on printed circuit board 21, e.g., via soldering. In front—relative to the working direction—of printed circuit board 21 with illuminating elements 22, an annular carrier 23 with convex lens 25 is located in front—relative to the direction of radiation—of illuminating elements 22.
Carrier 23 is composed of a transparent plastic. Lenses that serve to bundle the light rays are integrally formed in or on carrier 23. Convex lenses 25 are shown in FIG. 2. FIG. 2 also shows that printed circuit board 21 with illuminating elements 22, and carrier 23 with lens 25 are accommodated in transmission housing, on its end face. As an alternative, the system composed of printed circuit board with illuminating elements, and carrier with lens, can also be accommodated in a separate housing, which is capable of being installed (not shown), e.g., on the end face of the transmission housing or in the front region on the transmission housing.
The system composed of two convex lenses 24 and 25 for bundling light rays from illuminating element 22 is shown in greater detail in FIG. 3. The lower half of FIG. 3 is a cross-sectional view through printed circuit board 21 with illuminating element 22 in the form of an SMD light-emitting diode, and through carrier 23 with a first convex lens 24 and a second convex lens 25 located in front—relative to the direction of radiation—of illuminating element 22. The direction of radiation is indicated in FIG. 3 via dashed lines 26.
A second embodiment of an inventive hand-held power tool is shown in FIG. 4. Identical or similar components are labelled with the same reference numerals. A cordless screwdriver 200 has a housing 10 with a motor housing 11, a transmission housing 12, and a handle 13. Transmission housing 12 is shown in a exposed view, and the rest of housing 10 is shown open. Electric motor 17 is activatable using an on/off switch 14. A tool fitting 15 is located on the end face of transmission housing 12. An optical waveguide 52 is provided around tool fitting 15, and it is accommodated on the end face of transmission housing 12 in transmission housing 12. An LED is located at an opening 57 of optical waveguide 52, as light source 60, so that the light from the LED is fed into optical waveguide 52. Light source 60 includes wire terminations.
FIG. 5 shows that optical waveguide 52 is located around tool fitting 15 in an annular shape. Optical waveguide 52 has the advantage over the embodiment with several light-emitting diodes according to FIGS. 1 through 3 that a circumferential ring of light can be created, rather than punctiform illuminating elements. As a result, the working area of the hand-held power tool can be illuminated evenly.
Three embodiments of optical waveguides are shown in FIGS. 6 through 8; they can be inserted in the region of the tool fitting, particularly around the circumference of the tool fitting. FIG. 6 shows an optical waveguide 52 in the form of a closed ring with an opening 57 for feeding the light from a light source 60. As an alternative, FIG. 7 shows an optical waveguide 52 in the form of an open ring. Optical waveguide 52 includes a branching 59, at which optical waveguide 52 separates. The light from light source 60, which is fed at an opening 57 into optical waveguide 52, also separates accordingly at branching 59. FIG. 8 shows an annular optical waveguide 52 with several branchings 59, which project outwardly from optical waveguide 52. Branchings 59 are located at essentially identical intervals around annular optical waveguide 52. Branchings 59 have light apertures 58 on their free ends, through which the light can radiate outwardly essentially as points of light.
A further embodiment of an optical waveguide 52 is shown in FIG. 9. Optical waveguide 52 is designed as two pieces. It is composed of a first optical waveguide element 63 and a second optical waveguide element 64, which are interconnected via a socket connection 65 such that the light from light source 60 is transported from first optical waveguide element 63 to second optical waveguide element 64. First optical waveguide element 63 not only transports light to second optical waveguide element 64, it also serves to illuminate a lettering motif 65 (or other design elements).
It will be understood that each of the elements described above, or two or more together, may also find a useful application in other types of constructions differing from the type described above.
While the invention has been illustrated and described as embodied in a hand-held power tool, it is not intended to be limited to the details shown, since various modifications and structural changes may be made without departing in any way from the spirit of the present invention.
Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can, by applying current knowledge, readily adapt it for various applications without omitting features that, from the standpoint of prior art, fairly constitute essential characteristics of the generic or specific aspects of this invention.
Patent Application
20080074865
