Method and device for removing dents

Abstract

The invention is directed to a dent removing device for removing of dents in ferromagnetic sheet metals by way of inductive heating, said dent removing device comprising a working head with a housing with at least one working face foreseen to be brought in close contact with a dent in a sheet metal and at least one magnetic field generator for generating a magnetic field. According to the invention, the at least one working face comprises a recess for visual control of the dent removing, recess extending at least partially across the at least one working face.

Claims

1. A dent removing device for removing dents from ferromagnetic sheet metals by way of inductive heating, said dent removing device comprising: a. a working head including a housing with at least one working face to be brought in close contact with a dent in a sheet metal; b. at least one magnetic field generator for generating a magnetic field; wherein c. the housing comprises a recess for visual control of the dent removing process; d. said recess extending entirely across the at least one working face to divide the working face into at least two sections separated by the recess to permit visual inspection of the dent removing process; e. wherein the magnetic field generator comprises an electrical coil; and f. wherein the magnetic field generator comprises a substantially U-shaped core, said core comprising a first and a second leg and a yoke portion and at least one electrical coil is interconnected to the core.

2. The dent removing device according to claim 1, wherein the recess has a V- or U-shaped cross section.

3. The dent removing device according to claim 1, wherein the recess includes a constant or variable cross section.

4. The dent removing device according to claim 1, wherein the working head comprises more than one working face.

5. The dent removing device according to claim 4, wherein each working face comprises a thereto related magnetic field generator.

6. The dent removing device according to claim 5, wherein each working face includes a differently shaped recess.

7. The dent removing device according to claim 1, wherein an activating means is arranged at the housing, said activating means being suited to control the magnetic field.

8. The dent removing device according to claim 1, wherein at least one of a vibration generating means, an acoustic signal generator, and a visual display unit is integrated in the working head.

9. The dent removing device according to claim 1, wherein the first and/or second leg have a cross-section with a minimum diameter of between 4 and 10 mm, preferably between 6 and 9 mm.

10. The device for removing dents in sheet metal structures by inductive heating according to claim 1, further comprising: a. a power supply and control unit; and b. a cable suited to connect the power supply and control unit with the working head; wherein the power supply and control unit comprises: c. a time regulation means to control the duration of supplying the power to the working head; and d. a power regulation means to control the power supplied to the working head.

11. The device according to claim 10, wherein the time regulation means can be set in a range of between 0.5 seconds.

12. The dent removing device according to claim 1, wherein an area of the sheet metal being treated by the device in inductively heated.

13. The dent removing device according to claim 1, wherein an area of the sheet metal being treated by the device is visible to an operator via the recess.

14. A dent removing device for removing dents from ferromagnetic sheet metals, said dent removing device comprising: a. a working head including a housing operable with a single hand and including at least one working face to be brought in close contact with a dent in a sheet metal to heat the sheet metal through inductive heating; b. a recess for visual inspection of the dent removing process extending entirely across the at least one working face, and dividing the working face into at least two sections separated by the recess to permit the visual inspection; c. at least one magnetic field generator for generating a magnetic field; d. wherein the magnetic field generator comprises an electrical coil; and e. wherein the magnetic field generator comprises a substantially U-shaped core, said core comprising a first and a second leg and a yoke portion and at least one electrical coil is interconnected to the core.

15. A dent removing device for removing dents from ferromagnetic sheet metals by way of inductive heating, said dent removing device comprising: a. a working head including a housing with at least one working face to be brought in close contact with a dent in a sheet metal; b. at least one magnetic field generator for generating a magnetic field; wherein c. the housing comprises a recess for visual control of the dent removing process; d. said recess extending at least partially across the at least one working face; e. wherein the magnetic field generator comprises an electrical coil, wherein the magnetic field generator at least partially follows the contour of the recess; and f. wherein the magnetic field generator comprises a substantially U-shaped core, said core comprising a first and a second leg and a yoke portion and at least one electrical coil is interconnected to the core.

16. The dent removing device according to claim 15, wherein the recess extends persistent across the working face and divides the working face into at least two sections.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The herein described invention will be more fully understood from the detailed description given herein below and the accompanying drawings which should not be considered limiting to the invention described in the appended claims. The drawings are showing:

(2) FIG. 1 schematically shows a device for removing dents in a perspective view from above.

(3) FIG. 2 shows one embodiment of a working head in a perspective view from above.

(4) FIG. 3 shows the working head of FIG. 2 from the front.

(5) FIG. 4 shows the working head of FIG. 2 from the bottom.

(6) FIG. 5 shows another embodiment of a working head in a perspective view from above.

(7) FIG. 6 shows the working head of FIG. 5 from he front.

(8) FIG. 7 shows the working head of FIG. 5 from the bottom.

(9) FIG. 8 shows the working head of FIG. 5 in a perspective view from the below.

(10) FIG. 9 shows a working head and a sheet metal with a dent in a perspective view.

(11) FIG. 10 shows a working head and a sheet metal with a dent in a perspective view.

(12) FIG. 11 shows detail A of FIG. 10.

(13) FIG. 12 shows a working head positioned on a sheet metal n a perspective view.

(14) FIG. 13 shows detail B of FIG. 12.

(15) FIG. 14 shows a working head and a sheet metal in a perspective view.

DESCRIPTION OF PREFERRED EMBODIMENTS

(16) FIG. 1 shows a device 13 for removing dents in sheet metal structures. The device 13 comprises a working head 1 and a power supply and control unit 19, which comprises a time regulating means and a power regulating means. The working head 1 comprises a housing 2 and a first connector 4 for connecting the electrical power to the working head 1. At the outer surface of a housing 22 of the power supply and control unit 19, operating means are arranged to operate the time regulating means and the power regulating means. For example, switches 14, which are operatively connected to the time regulating means and power regulating means, may be arranged in the outer surface of the housing 22 of the power supply and control unit 19 and time scalar and power scalar may be arranged around the switches at the surface of the housing 22. By turning the switches to the corresponding time or power scalar, the duration of supplying the power and the power provided to the working head can be chosen. A handle 17 is mounted on the top surface of the housing 22 of the power supply and control unit 19 to facilitate the transport of the device. A second connector 16 is arranged at the housing 22 of the power supply and control unit 19. The first connector 4 of the working head 1 is connected with the second connector 16 of the power supply and control unit 19 by a cable 12.

(17) FIGS. 2, 3 and 4 show one embodiment of a working head 1 according to the invention. The housing 2 of the working head 1 comprises several side walls, a top portion 5 and a bottom portion 6. The working face 8, which is arranged at the bottom portion 6, being at least partially in contact with the sheet metal 20 during the removing process. As illustrated in FIG. 3, a recess 9 is arranged at the bottom portion 6 of the housing 2. In a preferred variant, the recess 9 is arranged approximately in the middle of the working face 8. The recess 9 is formed as a groove. In particular, the recess 9 has a V-shape or U-shape with the wider opening at the working surface 8 of the housing 2. An activating means 3, e.g. a button is arranged at the housing 2 of the working head 1, in particular on one of the side walls of the housing 2. As indicated by dashed lines, the magnetic field generator may have a substantially U-shaped form, or comprise a U-shaped core 26. FIG. 4 shows a bottom view of the working head 1. As shown in the Figures, the recess 9 may comprise chamfers 10 which facilitate the visual inspection of a dent.

(18) FIGS. 5, 6, 7 and 8 show another embodiment of the working head 1. This embodiment of the working head 1 differs from the embodiment mentioned above mainly in the shape of the housing 2 of the working head 1. In this embodiment, the dimension of the bottom portion 6 is smaller than the top portion 5. In particular, the diameter of the bottom portion 6 in y-direction is smaller than the diameter of the top portion 5.

(19) FIGS. 9, 10, 12 and 14 show different positions of the working head 1 relatively to the dent 21 in the sheet metal 20 and illustrate the different states of the dent removing process. In FIG. 9, before starting the dent removing process the working head 1 is above the dent 21 and the cable 12 is connected to the first connector 4 for electrical power supply. As can be seen, the working area of the sheet metal structure 20 is illuminated by sided light, which comprises an elongated light source 23. The light radiated be the light source 23 is reflected by the sheet metal structure 20. At the dent 21, light is reflected (resp. deflected) in a very specific manner that differs from the deflection in the adjacent regions without dent. Such disturbed light paths 24 help an operator to spot a dent 21. In FIG. 10, the working face 8 of the housing 2 of the working head 1 is brought into contact with the sheet metal 20 and the recess 9 has approximately the same position in x and y-directions as the dent 21. Thanks to the recess 9, the light path 24 form the light source 23 to the dent 21 and the operator's eye 25 (not shown) is not interrupted and hence the dent 21 is still clearly visible for the operator. FIG. 11 is an enlarged view of detail A of FIG. 10. It illustrates that the dent 21 is not fully covered by the working head and thus visible to an operator, because the recess 9 serves as a viewing window. FIG. 12 illustrates the end of the dent removing process. FIG. 13 is an enlarged view of the detail B of FIG. 12 and illustrates the situation after a successful removal of the dent. As shown in FIG. 14, after the dent removing process the working head 1 will be removed from the sheet metal 20.