RESONANCE METHOD FOR A VIBRATION SYSTEM, A CONVERTER, AN EXCITATION UNIT AND THE VIBRATION SYSTEM

Abstract

A resonance method for a vibration system for resonant vibration of an excitation unit having a vibrating mass includes detecting a deflection of the vibrating mass, differentiating the deflection to form a velocity of the vibrating mass; generating from the deflection and the velocity a mechanical phase position; forming from the mechanical phase position a corrected phase position by using a correction value; forming, based on the corrected phase position, an electrical angular frequency with a P-regulation; integrating the electrical angular frequency to determine an electrical phase position; forming from the electrical phase position a correction factor by using a trigonometric function; and applying the correction factor to an excitation setpoint value to generate a corrected excitation setpoint value. Also disclosed are a converter, an excitation unit having the converter, and a vibration system having the excitation unit and the vibrating mass.

Claims

1.-15. (canceled)

16. A resonance method for a vibration system for resonant vibration of an excitation unit having a vibrating mass, the method comprising: detecting a deflection of the vibrating mass; differentiating the deflection to form a velocity of the vibrating mass; generating from the deflection and the velocity a mechanical phase position; forming from the mechanical phase position a corrected phase position by using a correction value, forming, based on the corrected phase position, an electrical angular frequency with a P-regulation, integrating the electrical angular frequency to determine an electrical phase position; forming from the electrical phase position a correction factor by using a trigonometric function; and applying the correction factor to an excitation setpoint value to generate a corrected excitation setpoint value.

17. The resonance method of claim 16, further comprising forming from the electrical angular frequency a standardized velocity by dividing the velocity by the electrical angular frequency.

18. The resonance method of claim 16, wherein the correction value for phase position correction is a fed-back electrical phase position.

19. The resonance method of claim 18, wherein the fed-back electrical phase position is subtracted from the mechanical phase position.

20. The resonance method of claim 16, further comprising initializing the method by specifying an initial angular frequency or by using a last known electrical angular frequency.

21. The resonance method of claim 16, wherein the mechanical phase position is determined between a deflection amplitude of the deflection and the velocity, or as a phase position between the deflection amplitude of the deflection and the deflection.

22. The resonance method of claim 16, further comprising: detecting the deflection with a deflection signal from a deflection measuring apparatus; and correcting the deflection signal with a DC component depending on the installation location of the deflection measuring apparatus relative to the vibrating mass, wherein the DC component is predetermined by a DC component parameter or the DC component is determined by a DC component high-pass filter.

23. The resonance method of claim 16, wherein the excitation setpoint value is a setpoint current and the corrected excitation setpoint value is a corrected setpoint current.

24. The resonance method of claim 16, further comprising detecting faults by monitoring the electrical angular frequency for disturbances in the resonant vibration of the excitation unit and the vibrating mass.

25. A converter, comprising: a detection unit configured to detect a deflection of a vibrating mass; a first forming unit configured to form a velocity of the vibrating mass by differentiating the deflection; a generating unit configured to generate from the deflection and the velocity a mechanical phase position; a correction unit configured to form from the mechanical phase position a corrected phase position by using a correction value; a second forming unit configured to form, based on the corrected phase position, an electrical angular frequency with a P-regulation; a third forming unit configured to integrate the electrical angular frequency to determine an electrical phase position; a fourth forming unit configured to form from the electrical phase position a correction factor by using a trigonometric function; and an application unit configured to apply the correction factor to an excitation setpoint value to generate a corrected excitation setpoint value.

26. The converter of claim 25, further comprising a standardization unit configured to form from the electrical angular frequency a standardized velocity by dividing the velocity by the electrical angular frequency.

27. The converter of claim 25, wherein the correction value for phase position correction is a fed-back electrical phase position.

28. The converter of claim 27, wherein the fed-back electrical phase position is subtracted from the mechanical phase position.

29. An excitation unit, comprising: an electromagnet exciting a vibrating mass; a converter as set forth in claim 25 for operating the electromagnet; and a deflection measuring apparatus measuring the deflection of the vibrating mass with respect to a resting position of the vibrating mass.

30. The excitation unit of claim 29, further comprising a spring element connected to the vibrating mass.

31. The excitation unit of claim 29, wherein the converter comprises a standardization unit configured to form from the electrical angular frequency a standardized velocity by dividing the velocity by the electrical angular frequency.

32. The excitation unit of claim 29, wherein the correction value for phase position correction is a fed-back electrical phase position.

33. The excitation unit of claim 32, wherein the fed-back electrical phase position is subtracted from the mechanical phase position.

34. A vibration system, comprising: a vibration mass; and an excitation unit comprising an electromagnet exciting the vibrating mass, a converter as set forth in claim 25 for operating the electromagnet, and a deflection measuring apparatus measuring the deflection of the vibrating mass with respect to a resting position of the vibrating mass.

35. The vibration system of claim 34, embodied as a friction welding apparatus or as a transport apparatus.

Description

[0060] The properties, features and advantages of this invention described above and the manner in which they are achieved will become clearer and more readily comprehensible in connection with the following description of the exemplary embodiments, which are explained in more detail in connection with the figures. It is shown in:

[0061] FIG. 1 a structure chart of the resonance method according to the invention,

[0062] FIG. 2 a diagrammatic regulation representation of the resonance method according to the invention and

[0063] FIG. 3 a diagrammatic view of a friction welding apparatus with the converter according to the invention, the excitation unit according to the invention and the vibration system according to the invention.

[0064] FIG. 1 shows a structure chart of the resonance method 1 according to the invention with method steps for resonant vibration of an excitation unit with a vibrating mass.

[0065] During deflection detection 5, a deflection of the vibrating mass is detected. A deflection signal detected for this purpose by a deflection measuring apparatus can be corrected by a DC component as a function of the installation location of the deflection measuring apparatus with regard to the vibrating mass, wherein the DC component can be specified by a DC component parameter 34 or determined by a DC component high-pass filter 19.

[0066] By differentiating the deflection, a velocity of the vibrating mass is formed during velocity formation 6, the velocity being converted into a standardized velocity on the basis of the electrical angular frequency by dividing the velocity by the electrical angular frequency.

[0067] In phase position generation 7, a mechanical phase position is generated on the basis of the deflection and the velocity.

[0068] Via phase position correction 8, the mechanical phase position is converted into a corrected phase position by a correction value. In this case, the correction value is the electrical phase position fed back in a control loop, wherein preferably the fed-back electrical phase position is subtracted from the mechanical phase position.

[0069] Frequency formation 9 of an electrical angular frequency takes place by means of at least one P-regulation on the basis of the corrected phase position. For frequency formation 9, the P-regulation can also be designed as a PI-regulation or as a PID-regulation.

[0070] For a method initialization 16, an initial angular frequency can be specified or the last known electrical angular frequency can be used.

[0071] Furthermore, the electrical angular frequency can be monitored for faults in the resonant vibration of the excitation unit and the vibrating mass. Typical faults can have their origins, for example, in mechanical defects during the vibration of the vibrating mass, so that the required electrical angular frequency can become too low or too high and the resonance method may have to be interrupted.

[0072] In phase position formation 10 of an electrical phase position, integration takes place on the basis of the electrical angular frequency.

[0073] During factor formation 11 of a correction factor, a trigonometric function on the basis of the electrical phase position is used and the correction factor corrects an excitation setpoint value to a corrected excitation setpoint value during setpoint value application 12.

[0074] FIG. 2 shows a diagrammatic regulation representation of the resonance method 1 according to the invention. In this case, the resonance method 1 can be carried out by a converter, in particular by a regulation unit of the converter.

[0075] A detection means 21 is designed for deflection detection 5 of a deflection x of the vibrating mass. A deflection signal detected as deflection x by a deflection measuring apparatus is, as a function of the installation location of the deflection measuring apparatus with regard to the vibrating mass, corrected by means of a high-pass means 37 of a DC component high-pass filter 19 by a DC component.

[0076] A first forming means 22 differentiates the deflection x by means of the velocity formation 6 into a velocity v of the vibrating mass. The velocity v is furthermore converted into a velocity standardization 15 by a standardization means 35 in a standardized velocity v.sub.n on the basis of a fed-back electrical angular frequency ω.sub.el by dividing the velocity v by the electrical angular frequency ω.sub.el.

[0077] A generating means 23 is designed for phase position generation 7 of a mechanical phase position Θ.sub.m which takes place on the basis of the deflection x and the velocity v.

[0078] A correction means 24 is designed for phase position correction 8 of the mechanical phase position Θ.sub.m, the mechanical phase position Θ.sub.m being converted into a corrected phase position Θ.sub.k by means of a correction value k.sub.Θ. A fed-back electrical phase position Θ.sub.el is used as the correction value k.sub.Θ, the fed-back electrical phase position Θ.sub.el being subtracted from the mechanical phase position Θ.sub.m.

[0079] A second forming means 25 for frequency formation 9 of the electrical angular frequency ω.sub.el is designed on the basis of the corrected phase position Θ.sub.k by means of here a P-regulation, which may also be a PI-regulation or a PID regulation. The electrical angular frequency ω.sub.el is returned at this point to the standardization means 35 for velocity standardization 15.

[0080] An initial angular frequency ω.sub.in can be specified by an initialization means 36 for method initialization 16.

[0081] By means of a third forming means 26, a phase position formation 10 of the electrical phase position Θ.sub.el takes place by means of integration on the basis of the electrical angular frequency ω.sub.el. At this point, the electrical phase position Θ.sub.el is returned to the correction means 24 for phase position correction 8.

[0082] From a fourth forming means 27, a factor formation 11 of a correction factor k.sub.F is carried out by means of a trigonometric function based on the electrical phase position Θ.sub.el.

[0083] An application means 28, designed for the setpoint value application 12 of an excitation setpoint value 13 in the form of a setpoint current I.sub.S with the correction factor k.sub.F, generates a corrected excitation setpoint value 14 in the form of a corrected setpoint current I.sub.Sk. In particular, this corrected setpoint current I.sub.Sk is used to operate an electromagnet which is comprised by the excitation unit and excites resonant vibration of the vibrating mass.

[0084] FIG. 3 shows a diagrammatic view of a friction welding apparatus 32 with the converter 20 according to the invention, the excitation unit 4 according to the invention and the vibration system 2 according to the invention.

[0085] Here, the vibration system 2 is designed by way of example, as a friction welding apparatus 32 with the excitation unit 4 and a vibrating mass 3.

[0086] A first fastening means 41 for a first workpiece 43 is arranged on the vibrating mass 3. The vibrating mass 3 with the first fastening means 41 and the first workpiece 43 is mounted so as to be able to vibrate.

[0087] Directly opposite the first workpiece 43, a second workpiece 44 is connected to a second fastening means 42. In this case, the second workpiece 44 on the second fastening means 42 is fixed in a fixed manner with regard to the first workpiece 43 and is not mounted so as to be able to vibrate.

[0088] The excitation unit 4 for the vibration excitation of the vibrating mass 3 comprises the converter 20, an electromagnet 29, a further electromagnet 30, a first and second spring element 38,39 for mounting of the vibrating mass 3 so as to be able to vibrate, a deflection measuring apparatus 18 and a deflection signal transmitted from the deflection measuring apparatus 18 to the converter 20, which deflection signal has a measured actual value of deflection.

[0089] The deflection is measured by means of the deflection measuring apparatus 18 with regard to a resting position 31 of the vibrating mass 3.

[0090] The control method according to the invention can be carried out by means of the converter 20, in particular by means of the regulation unit 40 of the converter 20.

[0091] During operation of the friction welding apparatus 32, the first workpiece 43 fastened to the first fastening means 41 of the vibrating mass 3 is set into resonant vibrations with the excitation unit 4. The first workpiece 43, which is set into vibrations, rubs against the fixed second workpiece 44 which is not able to vibrate, frictional heat being generated and both workpieces 43,44 being welded to one another in an energy-efficient manner and in a high production quality.