ELECTRONIC PRINTED CIRCUIT BOARD

Abstract

A printed circuit board may include a top side, a bottom side, and a circumferential surface that connects the top side to the bottom side. The circumferential surface may have a toothing for forming a gear wheel. The toothing may be circumferentially closed and may be arranged over an entire surface area of the circumferential surface. The toothing may be configured as an involute toothing, an epicycloid toothing, a hypocycloid toothing, or a lantern gear toothing. The printed circuit board may be formed of fiber-reinforced plastic. Further, the printed circuit board may include a track, a surface structure, and/or a conductor track configured for inductive sampling, capacitive sampling, optical sampling, and/or acoustic sampling.

Claims

1.-15. (canceled)

16. A printed circuit board comprising: a top side; a bottom side; and a circumferential surface that connects the top side to the bottom side, wherein the circumferential surface includes a toothing that forms a gear wheel.

17. The printed circuit board of claim 16 wherein the toothing is circumferentially closed and disposed over an entire surface area of the circumferential surface.

18. The printed circuit board of claim 16 wherein the toothing is configured as an involute toothing, an epicycloid toothing, a hypocycloid toothing, or a lantern gear toothing.

19. The printed circuit board of claim 18 wherein the gear wheel is configured as a Maltese cross.

20. The printed circuit board of claim 16 comprising at least one of an electrical resistor, a capacitor, a diode, or a transistor.

21. The printed circuit board of claim 16 comprised of fiber-reinforced plastic.

22. The printed circuit board of claim 16 wherein at least one of the gear wheel or the toothing includes a surface structure.

23. The printed circuit board of claim 16 comprising at least one of a track, a surface structure, or a conductor track configured for at least one of inductive sampling, capacitive sampling, optical sampling, or acoustic sampling.

24. The printed circuit board of claim 23 comprising the track or the surface structure, wherein the track is comprised of projections and recesses, wherein the surface structure is comprised of projections and recesses.

25. The printed circuit board of claim 16 comprising a coating that includes at least one of MoS.sub.2, PTFE, graphite, or UHMWPE.

26. The printed circuit board of claim 25 wherein the coating is disposed on the toothing.

27. The printed circuit board of claim 16 wherein the circumferential surface and the toothing are disposed on a radially outer periphery of the printed circuit board.

28. A sensor unit comprising the printed circuit board of claim 16.

29. A method for producing a printed circuit board with a top side, a bottom side, and a circumferential surface that connects the top side to the bottom side, wherein the method comprises: forming a toothing on the circumferential surface of the printed circuit board.

30. The method of claim 29 wherein forming the toothing on the circumferential surface is performed by milling.

31. The method of claim 29 wherein forming the toothing on the circumferential surface is performed by punching.

32. The method of claim 29 wherein forming the toothing on the circumferential surface is performed by laser cutting.

33. The method of claim 29 wherein the toothing is formed circumferentially closed over an entire surface area of the circumferential surface.

34. The method of claim 29 wherein the toothing is an involute toothing, an epicycloid toothing, a hypocycloid toothing, or a lantern gear toothing.

Description

[0022] Preferred embodiments of the invention will be explained in more detail below with reference to the drawings. Identical or functionally identical components are in this case provided with the same reference signs throughout the figures, in which:

[0023] FIG. 1: shows a three-dimensional view of a printed circuit board,

[0024] FIG. 2: shows a schematic illustration of a sensor unit,

[0025] FIG. 3: shows a plan view of a printed circuit board,

[0026] FIG. 4: shows a plan view of a printed circuit board with an additional surface structure,

[0027] FIG. 5: shows a view of a detail of a toothing of a printed circuit board,

[0028] FIG. 6: shows a view of a detail of a further toothing of a printed circuit board,

[0029] FIG. 7: shows a schematic illustration of a rack-and-pinion gear mechanism with a toothed printed circuit board, and

[0030] FIG. 8: shows a side view of the printed circuit board from FIG. 1.

[0031] FIGS. 1 and 8 show a printed circuit board 1 which is part of a sensor unit. The printed circuit board 1 has a top side 2, a bottom side 3 and a circumferential surface 4, wherein the circumferential surface 4 connects the top side 2 to the bottom side 3. The circumferential surface 4 lies on the outer side and forms an outer circumferential surface. The printed circuit board 1 is of circular design. It has a decentralized circular opening 5. The outer circumferential surface 4 has, over the entire periphery, a toothing 6 for forming a gear wheel 7. The external toothing 6 of the printed circuit board 1 is realized by means of milling, punching laser cutting or ultrasonic cutting. A track 8 is applied on the surface of the top and/or bottom side 2, 3 of the printed circuit board 1. The track 8 is inherently closed and does not have a start or an end. The pattern or the surface structure of the track 8 is not of concentric design in relation to a rotation axis 100 of the gear wheel 7. The track 8 is circular and has a width b1 in the radial direction, in the plane of the top side 2 of the printed circuit board 1, which increases uniformly along the periphery of the circle over a first semicircle and decreases uniformly again over the second semicircle. The rate of increase and decrease of the width b1 is in each case continuous and constant over the entire periphery in this case. The center point of the circle of the track 8 does not lie on the rotation axis 100 of the gear wheel 7. The track 8 or the surface structure are preferably formed from copper. Furthermore, it is conceivable and possible for said track and/or surface structure to be formed from aluminum, silver, tin, nickel and/or gold. The track 8 and/or the surface structure are/is inductively, capacitively, optically or acoustically sampled.

[0032] The printed circuit board 1 furthermore has at least one of the following components: at least one electrical resistor, at least one capacitor, at least one diode and/or at least one transistor. The track 8, a surface structure and/or a conductor track are/is applied on the printed circuit board 1. The printed circuit board 1 preferably consists of fiber-reinforced plastic.

[0033] FIG. 2 schematically shows a sensor unit 9 which comprises two gear wheels 10, 11. The gear wheels 10, 11 form, with their outer toothing 12, 13, the printed circuit boards 1, 101. A first gear wheel 10 is connected in a rotationally fixed manner to a shaft 14, in particular the steering shaft of a motor vehicle, and concentrically surrounds it. The first gear wheel 10 has an externally directed toothing 12 which is arranged concentrically in relation to the shaft axis 140. This first toothing 12 of the first gear wheel 10 engages into a second encircling outwardly directed toothing 13 of a second gear wheel 11 which rolls on the first gear wheel 10. The second gear wheel 11 rotates about a second gear wheel axis 110 which is arranged parallel and offset in relation to the shaft axis 140 and is fixed in space. The rotational movement of the shaft 14 is therefore transmitted to the second gear wheel 11. The first and the second gear wheel 10, 11 are likewise formed by printed circuit boards 1, 101.

[0034] The number of teeth of the second gear wheel 11 is smaller than the number of teeth of the first gear wheel 10. The number of teeth of the first gear wheel 10 is not an integer multiple of the number of teeth of the second gear wheel 11. In this case, the first gear wheel 10 preferably has at least 3 times more teeth than the second gear wheel 11, further preferably 4 times more teeth than the second gear wheel 11. The toothing 12, 13 of the two gear wheels 10, 11 is formed on the corresponding printed circuit board. The two gear wheels 10, 11 are therefore in contact by means of the printed circuit boards.

[0035] The rotations of the first and of the second gear wheel 10, 11 are measured by means of a sensor 150 and the signals further to a control unit 15 which can determine from said signals an absolute rotation state, in particular a rotation angle of the shaft 14.

[0036] FIG. 3 illustrates a gear wheel 16 which forms a printed circuit board. The gear wheel 16 carries the above-described track 8. The two gear wheels of the sensor unit 9 illustrated in FIG. 2 are preferably designed so as to allow absolute determination of the rotation angle of the shaft 14.

[0037] FIG. 4 shows that the gear wheel 16 can have, in addition to the track 8, a surface structure 17 by means of which the rotation state of a shaft can be detected more accurately.

[0038] FIGS. 5 and 6 illustrate two exemplary toothings of a gear wheel 7, 10, 11, 16 which is designed as a printed circuit board. The toothing can be designed, as illustrated in FIG. 5, as a lantern gear toothing or as an involute, epicycloid or hypocycloid toothing. The toothing can be configured in an axially parallel or oblique manner or as an arcuate toothing. Furthermore, it is conceivable and possible for the teeth to be designed as a Maltese cross.

[0039] FIG. 7 illustrates a linear design of the sensor arrangement in the form of a rack-and-pinion gear mechanism 18, in which a gear wheel 19 which is designed as a printed circuit board rolls on a toothing 200 of a rack and pinion 20 and therefore can convert the rotation of the gear wheel 19 into a linear movement of the rack and pinion, and vice versa. A sensor unit, not illustrated, measures the rotation of the gear wheel 19 in the process.