Soldering Device, Soldering System And Method

Abstract

The invention relates to a soldering device for removing solder pearls and/or solder balls from the lower face of a printed circuit board, in particular a soldering device for a soldering system for a selective wave soldering process, comprising a brush device for removing solder pearls and/or solder balls from the lower face of a printed circuit board. The brush device has a brush which can be driven about a drive axis and which is designed to remove the solder pearls and/or solder balls, wherein a moving device is provided, said brush device being arranged on the moving device such that the brush device can be moved relative to the printed circuit board in the direction of an X, Y, and Z axis.

Claims

1. A soldering device with a brush device for removing solder pearls and/or solder balls from the circuit board, whereby the brush device has a brush that can be driven around a drive axis, and that is configured for removing solder pearls and/or solder balls, whereby a movement device is provided, whereby the brush device is arranged on the movement device so that it can be moved relative to the circuit board in the orthogonally to one another arranged direction of an X, Y or Z axis, characterized in that the brush device is arranged below the circuit board in such a manner that solder pearls and/or solder balls are removed from the underside of the circuit board, and in that an angle adjusting device is provided which is configured for adjusting a processing angle of the brush device in the range of approximately 0 to approximately 20 to the Z axis.

2. The soldering device according to claim 1, wherein the movement device is a portal system.

3. The soldering device according to claim 2, wherein the portal system has at least one X-axis drive, configured for moving the brush device along the X axis, wherein the portal system has at least one Y-axis drive, which is configured for moving the brush device along the Y axis and wherein the portal system has at least one Z-axis drive which is configured for moving the brush device along the Z axis.

4. The soldering device according to claim 3 wherein the axis drives are configured as linear drives, particularly as chain drives, screw drives, ball screw drives, roller screw drives, direct linear drives, hydraulic cylinders or/or pneumatic cylinders.

5. The soldering device according to claim 1, wherein the movement device is a manipulator of a robot.

6. The soldering device according to claim 1, wherein the brush device has a brush drive, which is configured for generating an oscillating rotating movement of the brush.

7. The soldering device according to claim 1, wherein the brush device is configured for draining electrostatic discharges.

8. The soldering device according to claim 1, wherein the brush has electrically conducting bristles.

9. The soldering device according to claim 1, wherein the brush is electrically connected to a ground connection of the soldering device.

10. The soldering device according to claim 1, wherein the brush has a brush surface arranged orthogonally to the drive axis, wherein the brush surface is circular or ring-shaped.

11. (canceled)

12. The soldering device according to claim 1, wherein the angle adjustment device includes at least one electrical adjustment motor.

13. The soldering device according to claim 1, wherein a collecting bin is provided, which is configured for collecting solder pearls and/or solder balls removed from the underside of the circuit board.

14. The soldering device according to claim 12, wherein a suction device is provided which is configured for generating a reduced pressure in the collecting bin.

15. A soldering system for a selective wave soldering process, including a soldering device with a brush device having a brush that can be driven around a drive axis, and that is configured for removing solder pearls and/or solder balls, whereby a movement device is provided, whereby the brush device is arranged on the movement device so that it can be moved relative to the circuit board in the orthogonally to one another arranged direction of an X, Y or Z axis.

16. (canceled)

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Additional details and advantageous additional developments can be derived from the following description, by reference to which an embodiment of the invention is described in more detail.

[0023] They show:

[0024] FIG. 1 a schematic side view of a brush device of a soldering device according to the invention for removing solder pearls and/or solder balls from an underside of a circuit board; and

[0025] FIG. 2 a schematic side view of a soldering device according to the invention for removing solder pearls and/or solder balls from an underside of a circuit board.

DETAILED DESCRIPTION

[0026] FIG. 1 shows a brush device 10 of a soldering device 12 shown in FIG. 2 for removing solder pearls and/or solder balls from an underside of a circuit board 14 shown in FIG. 2 in schematic side view. FIG. 2 shows a schematic side view of the soldering device 12 according to the invention. In FIG. 2 the circuit board 14, through which is inserted, from an upper side 16, an electronic component 18 with its contact pins 20 and is soldered from an underside 22 of the circuit board 14 to it, for example by selective wave soldering, is shown above the soldering device 12, in a soldering system for a selective wave soldering process not shown in the figures.

[0027] On the underside 22 of the circuit board 14, small solder pearls and/or solder balls 24, which were generated by a solder wave during selective wave soldering, are adhering in the area of the contact pins 20. These so-called solder pearls and/or solder balls 24 are undesirable and can lead to failure of the circuit board 14, respectively of the component 18, during the life of the circuit board 14, if they detach over time. Detached solder pearls and/or solder balls 24 can lead to short circuits, which can lead to destruction of an electronic component 18.

[0028] The soldering device 12 is configured overall for the removal of solder pearls and/or solder balls 24 from the underside 22 of the circuit board 14 and can in particular be configured to be built into a soldering system, not shown, for a selective wave soldering process.

[0029] The soldering device 12 has the brush device 10 shown in FIG. 1. In turn, the brush device 10 has a brush 28 that can be driven around a drive axis 26, which is configured for removing solder pearls and/or solder balls 24.

[0030] The brush device 10 has a brush drive 30, which is configured to generate an oscillating rotating movement of the brushes 28 around the drive axis 26. The brush drive 30 is configured as an electric drive wherein, in operation, the brushes 28 carry out oscillating rotating movements with a frequency of approximately 50 Hz to approximately 400 Hz, preferably with a frequency of approximately 250 Hz. Advantageously, the brush drive 30 is so configured that it carries out 14,000 oscillating movements per minute with a voltage of 24 volts (this corresponds to approximately 230 Hz), wherein the oscillation speed can be adjusted by controlling the voltage between 0 and 24 volts.

[0031] The brush 28 has a brush surface 32 arranged orthogonally to the drive axis 26, which is configured circularly (see FIG. 1). The brush 28 is cylindrical, i.e. the bristles 34 of the brush 28 extend cylindrically in the direction of the drive axis 26. In FIGS. 1 and 2, the bristles 34 are shown only schematically. The brush 28 has a brush diameter 36 in the range of approximately 1 mm to approximately 40 mm, preferably in the range of approximately 6 mm to approximately 20 mm, so that even with small structures and cramped conditions on the underside of 22 of the circuit board 14, reliable removal of solder pearls and/or solder balls 24 can be allowed.

[0032] In order to be able to avoid destruction of the electronic components 18 arranged on the circuit board 14 to be processed, the brush device 10 is configured for draining electrostatic discharges. Thus electrostatic discharges that occur can be drained through the brush device 10, without resulting in the destruction of components 18 due to electrostatic discharges.

[0033] In this case the brush 28 has electrically conducting bristles 34, which are made from a so-called ESD (electrostatic discharge) plastic or from electrically conducting carbon, or at least include it. The brush 28, respectively their bristles 34, are electrically connected in this case to a ground connection of the soldering device 12, respectively a ground connection of a soldering system not shown in the figures for a selective wave soldering process.

[0034] A collecting bin 38 is provided concentric with the drive axis 26, which is configured to collect the solder pearls and/or solder balls 24 removed from the underside 22 of the circuit board 14. The collecting bin 38 is bowl-shaped and surrounds the brush 28 in the circumferential direction, i.e. orthogonal to the drive axis 26, at least in part, so that the flying around of the solder pearls and/or solder balls 24 removed by the brush device 10 can be prevented by the use of the collecting bin 38. Furthermore, contamination, for example in the operating area of a soldering system for a selective wave soldering process, by removed solder pearls and/or solder balls 24, can also be prevented. In order to be able to prevent expulsion of solder pearls and/or solder balls 24 already collected, it is also conceivable that the collecting bin 38 is not movement-coupled with the brush 28. In this case it is conceivable that the collecting bin 38 is arranged on a hollow shaft which is connected with the drive 30, wherein the brush 28-driving drive shaft is carried through the hollow shaft.

[0035] It is conceivable that a suction device 37 is provided, which is configured for generating a reduced pressure in the collecting bin 38. The suction device 37 can for example, in this case, include a vacuum pump and be connected with the collecting bin 38 by means of a hose 39. Thus removed solder pearls and/or solder balls 24 can be sucked away by the use of the suction device 37 and thus be safely collected by the collecting bin 38.

[0036] As can be ascertained in FIG. 2, the brush device 10 is so arranged, on a movement device 40 configured as a portal system, that it can be moved relative to the circuit board in the direction of an X, Y and Z axis 42, 44, 46. The X axis is designated by the double arrow 42, wherein the Y axis is designated by the double arrow 44 and wherein the Z axis is designated by the double arrow 46. X, Y and Z axes 42, 44, 46 are understood to mean the axes of an axis system as customarily employed in machine tools and in which all axes are arranged orthogonal to one another. Advantageously, the X and Y axes 42, 44 are arranged parallel to the circuit board 14, so that a movement of the brush device 10 in the X-Y plane spanned by the X and Y axes 42, 44 leads to a shifting of the brush device 10 relative to the circuit board 14, wherein a separation in the direction of the Z axis 46 thereby remains unchanged. This separation in the direction of the Z axis 46 can be changed by a movement of the brush device 10 in the direction of the Z axis 46.

[0037] The portal system 40 has two Y-axis drives 48, one X-axis drive 50 as well as a Z-axis drive 52. The X-axis drive 50 is configured for moving the brush device 10 along the X axis 42. The Y-axis drive 48 is configured for moving the brush device 10 along the Y axis 44. In addition, the Z-axis drive 52 is configured for moving the brush device 10 along the Z axis 46. The axis drive 48, 50, 52 configured as linear drives are consequently arranged to be movable with respect to one another, so that movement of the Y-axis drive 48 leads to a shifting of the X-axis drive 50 and of the Z-axis drive 52 arranged on the X-axis drive 50 in the direction of the Y axis 44, wherein a movement of the X-axis drive 50 leads to a shifting of the Z-axis drive 52, arranged on the X-axis drive 50, in the direction of the X axis 42.

[0038] Through the use of a portal system 40, it is conceivable to build the device 12 into an already existing soldering system for a selective wave soldering process with a separate portal system 40. It is also conceivable, however, to install the brush device 10 into a soldering system for a selective wave soldering process which has two separate movable solder nozzles, wherein the brush device 10 is provided in place of a second solder nozzle.

[0039] In order to be able to position the brush 28 relative to the circuit board 14, respectively to the contact pins 20 inserted through the circuit board 14, even with cramped conditions on the underside 22 of the circuit board 14, and thus allow reliable removal of solder pearls and/or solder balls 24, an angle adjusting device 54 with an electrical adjustment motor is provided, which is configured for adjusting a processing angle of the brush device 10 in the range of approximately 0 to approximately 20 to the Z axis 46 in the direction of the double arrow 56. In this case, a processing angle is understood to be an angle between the drive axis 26 of the brush device 10 and the Z axis of the movement device 40.

[0040] In operation, the brush 28 of the brush device 10 is automatically, under CNC control for example, moved along the contact pins 20 by means of the portal system 40, so that solder pearls and/or solder balls 24 can be removed from the underside 22 of the circuit board 14.

[0041] Overall, a facility can be achieved with the soldering device 12 by which a simple, safe and automated removal of solder pearls and/or solder balls 24 from an underside 22 of a circuit board 14 can be made possible.