Sonotrode apparatus and device for acoustic levitation, and control device and method

Abstract

Sonotrodes are used when examining substances on the basis of acoustic levitation. In order to obtain a reproducible measurement result or to extend the possible uses of devices of this kind, the respective sonotrode has to meet a whole range of requirements. Exact tuning of the frequency and clean interaction between the sonotrode and a frequency generator are particularly important. The present invention proposes that a sonic horn and a main body of the sonotrode are provided as different parts and, in this case, the sonic horn can be mounted on or in the main body in a specific manner, in particular for operation at low voltage in such a way that the amplitude or operating voltage remains below a comparatively low maximum low-voltage value, in particular 50 Vpp. The formation of heat can be prevented in this way. The present invention further relates to a control or production method for a sonotrode apparatus of this kind. In this case, it is respectively possible to extend the range of use and to improve the reproducibility or quality of the measurement results.

Claims

1. A sonotrode device for providing sonic waves for examinations by means of acoustic levitation, comprising: a base body; and a sonic horn for emitting sonic waves in the direction of a reflector; wherein the sonic horn and the base body are different parts; wherein the sonic horn is mountable in a fastening point at an installation depth on or in the base body; wherein the sonic horn comprises a shaft with coupling mountable at the installation depth in the fastening point in the base body; wherein the base body comprises coupling including a cavity or pouch for coupling the sonic horn in the fastening point; and wherein a hollow space surrounding the shaft is formed between an outer shall of the shaft and a wall of the cavity or pouch.

2. The sonotrode device according to claim 1, wherein the sonic horn comprises a shaft with coupling means, which is mountable at the installation depth in the fastening point on or in the base body.

3. The sonotrode device according to claim 1, at least wherein the sonotrode device comprises a high pressure resistant housing and is configured for operation at high pressure above 200 bar or wherein the sonotrode device is configured for providing the sonic waves at low voltage or wherein the sonotrode device comprises a low voltage source.

4. The sonotrode device according to claim 1, wherein the fastening point is configured for fastening in at least a form-fit or force-fit manner, wherein the fastening point preferably also comprises at least a fitting or a centering.

5. The sonotrode device according to claim 1, wherein the base body comprises coupling means including a cavity or pouch for coupling the sonic horn in the fastening point.

6. The sonotrode device according to claim 1, wherein a distance between the inner end of the sonic horn and an inner end of a/the unit for forwarding sound is adjustable, or wherein the installation depth of the sonic horn in the base body or the installation depth in the sonic horn is adjustable, or wherein an installation depth of a/the unit for forwarding sound in the base body is adjustable.

7. The sonotrode device according to claim 1, wherein a/the shaft of the sonic horn is guided through a guide-through of a high pressure resistant housing, or wherein a/the shaft of the sonic horn is sealed in a/the guide-through of a high pressure resistant housing.

8. The apparatus for examining substances by means of acoustic levitation, wherein the apparatus comprises at least one sonotrode device according to claim 1 and is configured for operation at least at high pressure up to 200 bar or at low voltage oscillation amplitudes, wherein the apparatus comprises a control device which is configured to control the sonotrode device or a frequency generator or amplifier of the apparatus depending on pressure measurement values or temperature measurement values, wherein the control device is adapted to at least one parameter by adjusting the control device to the fastening point or the installation depth, to a/the connection mechanism or to a/the coupling on the base body of the sonotrode device.

9. The apparatus according to claim 8, at least wherein the apparatus comprises a gas-proof and optionally high pressure resistant housing, in which the sonotrode device is at least partially arranged, or wherein the apparatus is configured to operate the sonotrode device free of cooling energy without active cooling.

10. A method for controlling a sonotrode device according to claim 1 or for controlling an apparatus for examining substances by means of acoustic levitation, wherein the sonotrode device is applied with a frequency depending on the natural frequency thereof, wherein the sonotrode device is operated at least at high pressure or low voltage oscillation amplitudes.

11. The method for examining substances by means of acoustic levitation by using the sonotrode device of claim 1, wherein the sonotrode device is operated at a low voltage, which describes an amplitude of the generated acoustic wave.

12. The method for examining substances by means of acoustic levitation by using the sonotrode device of claim 1 in an apparatus, wherein a sonic horn of the sonotrode device is guided through a wall of the apparatus and is arranged separately from the base body of the sonotrode device in an examination chamber and is soundproof relative to the base body, and wherein the sonotrode device is operated at least at high pressure over 200 bar or at oscillation amplitudes below 50 Vpp.

13. The method for examining substances by means of acoustic levitation by using the sonotrode of claim 1, wherein the sonotrode device is controlled by a control device depending on the natural frequency thereof, wherein the control device is individually adapted to at least one parameter of the sonotrode device including the natural frequency thereof.

14. A mounting kit for a sonotrode according to claim 1 wherein the mounting kit comprises at least one sonic horn as discrete part, wherein a base body of the sonotrode/sonotrode device comprises coupling means which are formed corresponding to coupling means on a shaft of the sonic horn and on which the sonic horn is mountable in a definable installation depth.

15. The sonotrode according to claim 1 obtained by mounting a shaft of a sonic horn provided separately from the base body of the sonotrode/sonotrode device in a fastening point in a predefined installation depth on or in the base body, wherein the natural frequency of the sonotrode/sonotrode device is defined through the mounting.

16. The sonotrode device according to claim 3, wherein the sonotrode device is configured for providing the sonic waves at low voltage, wherein the amplitude of emitted sonic waves is kept below 50 Vpp.

17. A method for examining substances by means of acoustic levitation by using the sonotrode device of claim 1 in an apparatus for examining substances by means of acoustic levitation, wherein the sonotrode device is operated at below 50 Vpp for the voltage magnitude.

Description

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

(1) The invention will be described in more detail in the following figures of the drawings, wherein reference is made to the other figures of the drawings for reference characters that are not explicitly described in one respective figure of the drawings. The figures show in:

(2) FIG. 1 in a partially sectional side view in a schematic illustration, a sonotrode/sonotrode device according to an exemplary embodiment of the invention;

(3) FIG. 2 in a partially sectional side view in a schematic illustration, a sonotrode/sonotrode device according to a further exemplary embodiment of the invention;

(4) FIG. 3 in a partially sectional side view in a schematic illustration, a sonotrode/sonotrode device according to a further exemplary embodiment of the invention;

(5) FIG. 4 in a schematic illustration, an apparatus for examining substances by means of acoustic levitation according to an exemplary embodiment of the invention;

(6) FIG. 5 in a partially sectional side view in a schematic illustration, a sonotrode/sonotrode device according to a further exemplary embodiment of the invention;

(7) FIGS. 6A, 6B, 6C in each case in a sectional side view in a schematic illustration, a sonotrode/sonotrode device according to one of the exemplary embodiments of the invention in each case mounted on a housing or a high-pressure view cell; and

(8) FIG. 7 in a schematic form, an overview concerning a user guidance or control steps or setting steps of an apparatus or of a control device according to an exemplary embodiment of the invention.

DETAILED DESCRIPTION OF THE FIGURES

(9) In FIG. 1, a sonotrode device 10 with a base body 11, in particular a first end mass, with a (second) end mass 17, a unit for forwarding sound 12 with a first electrode 12.7 and a second electrode 12.8 and with a sonic horn 13 is illustrated. The horn 13 preferably consists of metal. The two electrodes contact in each case an oscillating element 12.1, 12.2, in particular a piezo-ceramic. The respective electric contacting 12.4 can be effected on front faces. The number of electrodes or oscillating elements can vary. Fastening means 12.3, in particular a screw with male thread, fix these components on the base body 11 in the type of a sandwich. The fastening means 12.3 can clamp or brace the five components 12.1, 12.2, 12.7, 12.8. 17 arranged in a row to the base body 11.

(10) In FIG. 1, the sonotrode device 10 is illustrated aligned in the vertical direction. During operation, the sonotrode device 10 can also be aligned in horizontal direction rotated by 90 (FIG. 3).

(11) The base body 11 comprises at least one coupling means or coupling element 11.1 for the sonic horn. In the illustrated example, the coupling means includes a female thread. Furthermore, the base body 11 comprises, on a first front face, a cavity or pouch 11.7, on which the coupling means 11.1 are formed or from which the coupling means 11.1 extend in the direction of the unit for forwarding sound 12, in particular in parallel to the fastening means 12.3 or along the same geometric axis. The pouch 11.7 has, e.g. a positive effect on the heat generation of the sonotrode device.

(12) The sonic horn 13 comprises corresponding coupling means 13.1, in particular including a male thread which is provided on a shaft 13.5, in particular at the end of the shaft. The coupling means 13.1 can include a centering 13.5b, in particular a fitting in addition to a screw connection. The position of the centering 13.5b can deviate from the arrangement shown, in particular if also the installation depths or the location, at which structure-borne sound is transferred from the base body to the sonic horn, is influenced by means of the centering. Such a centering may only be indicated in FIG. 1, can also be provided in the sonic horns according to the further exemplary embodiments. A centering arranged at an outer edge of the pouch 11.7 allows a particularly precise alignment of the shaft 13.5. On a free end, the sonic horn 13 comprises a plate 13.7. Sound waves can be emitted and reflected from the plate 13.7.

(13) Opposite of the sonic horn 13, the base body 11 comprises fastening means 11.2 for the unit for forwarding sound, in particular including a female thread. The fastening means 11.2 are arranged preferably along the same geometrical axis as the coupling means 11.1 or at least in parallel thereto. The shaft is mounted in the base body with an installation depth x2 (FIGS. 3, 5) in the fastening point P2.

(14) The first oscillating element 12.1 abuts on a second front face 11.4 of the base body 11. The fastening means 12.3 abuts on a front face 17.4 of the second end mass 17. The second end mass 17 comprises a through-hole 17.6, through which the fastening means 12.3 is guided. According to a variant, a female thread corresponding with the fastening means 12.3 is only formed on the base body 11.

(15) The separate sonic horn 13 now can be fastened on the base body 11 in different ways, in particular without having to change the fastening of the unit for forwarding sound. As a result, in each case particularly suitable form-fit and/or force-fit coupling means 11.1 can also be specifically formed. For example, the distance between the plate 13.7 and the front face 11.3 is adjustable.

(16) In FIG. 2, a variant is shown, in which the horn 13 is also directly connected to the fastening means 12.3. As a result, the base body 11 comprises a through-hole 11.6 through which fastening means 12.3 are guided. A connecting mechanism 15 for connecting the horn 13 with the unit for forwarding sound 12 or with the fastening means 12.3 ensures that these components can be directly coupled to one another in terms of oscillation. The fastening means 12.3 can brace the five components 12.1, 12.2, 12.7, 12.8, 17 arranged in a row to the base body 11 and thereby also brace the horn 13 to the base body 11 or the unit for forwarding sound 12. The connecting mechanism 15 can, e.g. include a female thread hole in the shaft 13.5 which is formed corresponding to a male thread of the fastening means 12.3. Here, the fastening means 12.3 does not necessarily need to directly interact with the base body 11.

(17) With the example of FIG. 2, also a fitting 13.5d is shown, which is formed on a section of the shaft 13.5. The position indicated can also vary. Such a fitting may only be indicated in FIG. 2, can also be provided in the sonic horns according to the further exemplary embodiments.

(18) In FIG. 3, a variant is shown in which a/the sonic horn 13 is fastened on the base body 11 in one fastening point P2 or at least one mounting point, wherein the position of the sonic horn 13 can be adjusted, for example through a predefined tightening torque. The shaft 13.5 can form a fitting together with the coupling means 11.1, at least in sections. The coupling means 11.1 can ensure a fitting or are configured, e.g. for a press-fitting. An inner end 13.5a of the sonic horn is arranged in a mounting depth/installation depth x2, in particular measured form the corresponding front face 11.3 to the inner end 13.5a. The installation depth x2 can be defined independent of dimensions of the pouch. According to a variant, the installation depth x2 can correspond to the depth of the pouch 11.7. In the arrangement shown in FIG. 3, the sonic horn can also be moved further into the base body until corresponding contact surfaces 11.1a, 13.5a on the front face side abut. The inner end of the sonic horn is arranged at a distance x1 from an inner end of the unit for forwarding sound 12 or the fastening means 12.3. The installation depth x2 and thereby also optionally the distance x1 can be varied, in particular manually. The unit for forwarding sound 12 is fastened on the base body 11 in a fastening point P1 or a mounting point. An inner end of the unit for forwarding sound 12 or of the fastening means 12.3 is arranged in a mounting depth/installation depth x3, in particular measured from the corresponding front face 11.4.

(19) The variant shown in FIG. 3 can be combined with the features of the variants shown in FIGS. 1 and 2. In particular, optionally also a connecting mechanism 15 or a coupling can be provided.

(20) FIG. 4 shows an apparatus 100 for examining substances by means of acoustic levitation which includes a frequency generator 101, a reflector 102, a preferably high-pressure resistant and/or thermally insulated housing 103, a/the sonotrode device 10 as well as at least one temperature measuring unit 30 and at least one pressure measuring unit 40 and further a control device 50 connected therewith. Within the housing 103, a wave field W is generated between the sonotrode device 10 and the reflector 102. Here, the control device 50 can communicate with the measuring units 30, 40 of the sonotrode device 10, the reflector 102 and/or the frequency generator 101. An operating panel 60 with an optical or opto-acoustic input mask or display/touchscreen is arranged accessible for a user on an outer surface of the apparatus 100.

(21) Furthermore, first and second sealings or sealing systems 105, 107 are indicated. The sealings allow a high-pressure compatible structure. The sealings can be configured, e.g. for a pressure difference in the range of 200 bar or 1000 bar. Here, the sealings can cause also a sound insulation of individual components in each case relative to one another. A first sealing system 105 here can relate, e.g. to the sealing of individual components in the sonotrode device 10 or the housing 103, and a second sealing system 107 can relate, e.g. to the sealing of individual measuring units 30, 40. Each sealing system can include one or multiple O rings. Here, sealings in the form of O rings can fulfil a soundproofing function. The arrangement of the sealings/sealing systems is indicated only in an exemplary manner and can deviate therefrom. For example, sealings can also be provided directly at the sonotrode device 10.

(22) In FIG. 5, a sonotrode device 10 with a base body 11 is shown which comprises a plug 11.8 on a front face side 11.3 (not shown) directed to the reflector. The plug 11.8 can be a constituent of coupling means 11.1 or provide these. The coupling means 11.1 in this case include a male thread which is formed on the plug 11.8. The sonic horn 13 comprises a cavity 13.8 formed geometrically corresponding to the plug 11.8. Coupling means 13.1 of the sonic horn 13 are formed in this cavity 13.8 and include a female thread. Optionally, alternative types of form-fit and/or force-fit coupling can be provided deviating from the thread. Optionally, a pouch can also be provided on the sonic horn, which, e.g. has an inner diameter which is greater than the diameter of the cavity 13.8 by the factor of 1.2 to 2. Cavity and pouch then can merge into one another at a shoulder. As also indicated in FIG. 6C, the fastening can be effected, e.g. exclusively on a bottom of the cavity 13.8. The shaft is mounted on the base body in the installation depth x2 in a fastening point P2.

(23) In the FIGS. 6a, 6B and 6c, some optional variants for the mounting of the sonotrode device according to the invention are indicated. As the sonic horn 13 is designed separately from the base body 11, the mounting can be effected in a particularly flexible manner. For example, the sonic horn 13 can be clamped or tightened with the base body 11 on a housing wall 103, e.g. on a wall of a high-pressure view cell (FIGS. 6A, 6C). Optionally, the shaft 13.5 can also be guided through the wall 103 without being braced (FIG. 6B).

(24) In detail, FIG. 6A shows a sonic horn 13 with a front plate 13.7a and a rear plate or shoulder 13.7b, wherein the rear plate 13.7b can be pressed/braced to the outer surface of the housing 103 in the type of a shoulder. As well, the front face 11.3 of the base body 11 can be braced to an inner surface of the housing 103. The base body 11 here can be arranged outside of an examination chamber. Between the sonotrode device 10 and the wall 103, two types of sealings 105, 107 are provided, wherein both types can be designed as O ring sealing. On the shaft 13.5, a sealing 105 is arranged which can center the shaft 13.5 in the hole of the wall 103 (in particular optionally also additionally to a centering provided in the fastening point P2) and can acoustically decouple the horn 13 from the wall 103. On the front face sides, in each case a sealing 107 is provided which can withstand a relatively great bracing/pressing force. Here, the sonotrode device 10 can be arranged in a predefined angle relative to the wall 103 and thereby be aligned. The respective sealing can be arranged, e.g. on a shoulder not shown in detail or in a groove. An acoustic decoupling can be caused by means of this sealing system 107. The front face side 11.3 and the side of the rear plate 13.7b directing to the base body 11 here can be aligned in parallel to one another which allows a mounting of the horn 13 in different rotational positions.

(25) The sonic horn 13 shown in FIG. 6B is guided through a guide-through 103.1 in which an O ring sealing 105 retained in a groove is arranged. Further sealings are not necessarily required. The sealing 105 abuts on the shaft 13.5, wherein the shaft 13.5 comprises, e.g. a shoulder, a groove and/or a corresponding sealing surface for arranging the sealing 105. The base body not illustrated in detail needs not be fastened to the wall 103 but can be fastened to another part of the housing. The arrangement shown in FIG. 6B allows a particularly well acoustic decoupling of the horn 13 from the housing, even if the horn needs to be arranged in, e.g. a high-pressure view cell. The sealing or acoustic decoupling can be effected by means of a single sealing. This allows not least a mounting/attuning in a simple or flexible manner.

(26) FIG. 6C shows a sonotrode device 10 mounted braced with a plug 11.8, for example according to the exemplary embodiment shown in FIG. 5. The plug 11.8 thus can be significantly longer than the corresponding cavity or pouch 13.8, wherein the coupling means 11.1 are provided preferably only in front region of the plug. In a middle or rear region of the plug, e.g. a shoulder, a groove and/or a corresponding sealing surface for arranging the sealing 105 is provided. In other words: the plug 11.8 is configured to ensure a coupling function as well as a sealing function. The sealings 107 abutting on the front face side can have greater dimensions, in particular a greater diameter than the sealing 105, in particular for receiving pressing/bracing forces and/or for setting a sealing effect in manner as precise as possible.

(27) FIG. 7 shows a flow chart for an exemplary menu navigation in controlling a sonotrode according to the invention. Individual steps of a starting process of an apparatus according to the invention for examinations by means of acoustic levitation are indicated through a dashed line as starting method including steps S1 to S4. In step S1, a user switches the apparatus on. In step S2, the apparatus takes on the standby mode. In step S3, a PC is switched on. In step S4, an examination software is started.

(28) After switching on the apparatus, a menu exemplary described here, e.g. including the following options O1 to O6 is displayed to the user: O1 VIDEO UPLOAD, O2 LIVE METERING, O3 TUTORIAL, O4 SETTINGS, O5 QUIT, O6 ABOUT. Starting from this input mask, different user instructions can be made. Here, also an operation with respect to the examination and measurement of physical substance data can be effected, in particular via one or multiple menu item(s).

(29) The user then can start, e.g. a measurement (LIVE METERING) (step S5) and thereby select (step S6) whether the control is to be effected automatically in the autopilot mode (selection item C1a) or manually (selection item C1b), in particular also during operation (selection item C1). The selection items C2, C3 can also be buttons or touch surfaces 61, on which the frequency (C2) and the amplitude (C3) is adjustable, which also in each case is displayed (D1, D2), and which automatically can be adopted (step 9) by a control device in response to an input. Here, a working operation frequency is set, in particular depending on pressure or temperature values which can be measured, e.g. by means of respective measurement units/sensors in a housing, even in a continuous manner. In particular, the signal shape (V1), in particular rectangle, and the basic frequency (V2), e.g. 40 kHz, and the basic amplitude (V3), e.g. 10 Vpp is adjustable. Here, the frequency can be automatically adopted by the activated autopilot (step S8). After setting these parameters, the wave field can be generated and a sample can be examined (step 7; channel on). The placeholders R1, R2 stand for a sum of operation state data for a certain environment, in particular for rectangular signal shape and frequency determination from an expression considering pressure and temperature, as well as a basic amplitude of, e.g. 10 Vpp (R1), or for amplifier properties like the impedance, e.g. 50 Ohm and alternating voltage (R2).

(30) The user can optionally work with video sequences (VIDEO UPLOAD). The user can optionally load or display technical information or instruction manuals (TUTORIAL). The user can optionally make settings to the software of the control device or to the apparatus (SETTINGS). As a result, also an adjustment or a precise tuning can be made, in particular by adjusting parameters like the natural frequency of the sonotrode device by the control device. The user can optionally exit the input mask (QUIT), in particular to turn the apparatus off, or can have contact information or access data or program or apparatus versions (ABOUT) displayed.

(31) The input program only roughly described here or the control device operable therewith facilitates the manual or automated execution of measurements and records for measurement results as well as the diagnose or remote maintenance of the apparatus. Examinations can be executed on highly-standardized or professional level, in particular reproducible for third parties. FIG. 7 also shows that the levitation measurement can be executed with a comparatively very low basic amplitude in the range of 10 Vpp, which is advantageous in particular with respect to high-pressure applications.

LIST OF REFERENCE CHARACTERS

(32) 10 Sonotrode device 11 Base body, in particular (first) end mass 11.1 Coupling means or coupling element for sonic horn 11.1a Contact surface geometrically corresponding to contact surface on shaft 11.2 Fastening means for unit for forwarding sound, in particular thread 11.3 First front face, in particular directed to the reflector 11.4 Second front face, in particular directed to the unit for forwarding sound 11.6 Through-hole 11.7 Cavity or pouch 11.8 Plug 12 Unit for forwarding sound/sound emission 12.1 Oscillating element/oscillation exciter, in particular (first) piezo-ceramic 12.2 Oscillating element/oscillation exciter, in particular (second) piezo-ceramic 12.3 Fastening means, in particular screw 12.4 Electrical contacting 12.7 (first) electrode 12.8 (second) electrode 13 Sonic horn 13.1 Coupling means or coupling element 13.5 Shaft 13.5a Inner end 13.5b Centering 13.5c Front face with contact surface geometrically corresponding to contact surface of the coupling means 13.5d Fitting 13.7 Plate 13.7a front plate 13.7b rear plate 13.8 Cavity or pouch 15 Connecting mechanism for connection of unit for forwarding sound with sonic horn 17 (second) end mass 17.4 Front face 17.6 Through-hole 30 Temperature measuring unit 40 Pressure measuring unit 50 Control device 60 Operation panel with optical or opto-acoustical input mask or display/touch screen 61 Touch surface 100 Apparatus for examining and/or fixing of substances, samples or objects, in particular by means of acoustic levitation 101 Frequency generator 102 Reflector 103 Housing, preferably high-pressure resistant and/or thermally insulated 103.1 Guide-through, opening, access 105 First sealing or first sealing system 107 Second sealing or second sealing system C1, C1a, C1b, C2, C3 Selection items or decision options for a user D1, D2 Display with displayed parameter O1, O2, O3, O4, O5, O6 Options for a user P1 Fastening point/mounting point for unit for forwarding sound P2 Fastening point/mounting point for sonic horn R1, R2 Place holder for operation state data and optionally also display S1, S2, S3, S4, S5, S6, S7, S8, S9 Steps during operation of the apparatus V1, V2, V3 Variables or attunable parameters W Wave field x1 Distance between inner end of the sonic horn and inner end of the unit for forwarding sound x2 Installation depth of the sonic horn, in particular measured form the corresponding front face side x3 Installation depth of the unit for forwarding sound, in particular measured from the corresponding front face side