ULTRASONIC TOOL AND METHOD FOR MANUFACTURING THE TOOL

Abstract

An ultrasonic cutting tool for use in an ultrasonic instrument, the tool being a blade manufactured from a tubular blank by flattening a section of the blank. The blade includes a flat section designed to be used for cutting, a tubular section, and a transition section joining the flat section to the tubular section. The tubular section is joined to or includes an attachment section for attaching the blade to an ultrasonic generator and serving as a conduit to bring a cooling fluid to the distal end or to suck particles into the hand tool.

Claims

1. An ultrasonic cutting tool, for use in an ultrasonic instrument, the tool being a blade manufactured from a tubular blank by flattening a section of the blank, the blade comprising: a flat section configured to be used for cutting, a tubular section, and a transition section joining the flat section to the tubular section, the tubular section being joined to or comprising an attachment section for attaching the blade to an ultrasonic generator.

2. The tool of claim 1, wherein the flat section forms one or more channels suited to guide a fluid along the inside of the blade.

3. The tool of claim 1, wherein the flat section comprises one or more holes in fluid communication with the one or more channels.

4. The tool of claim 1, wherein one or more edges of the flat section comprise teeth.

5. The tool of claim 1, wherein one or more edges of the flat section are machined to constitute a cutting edge.

6. The tool of claim 1, wherein one or more edges of the flat section comprise one or more notches constituting openings that are in liquid communication with the one or more channels.

7. The tool of claim 1, wherein an outer surface of the flat section is machined to comprise a structured surface with teeth or grooves.

8. The tool of claim 1, wherein the flat section comprises one or more weld lines, in particular running along a longitudinal direction in which the flat section extends.

9. The tool of claim 8, wherein the one or more weld lines create separate longitudinal channels in a direction in which the flat section extends.

10. The tool of claim 8, wherein the one or more weld lines are arranged to distribute coolant flowing in a direction of a distal end of the flat section towards a side of the flat section.

11. The tool of claim 1, wherein the attachment section comprises an internal thread or an external thread.

12. The tool of claim 1, wherein the attachment section comprises a longitudinal conduit in liquid communication with an inside of the tubular section.

13. Method for manufacturing the blade according to claim 1, wherein the method comprises the steps of: providing a tubular blank; pressing a distal end of the blank to form the flat section, leaving a proximal end of the blank in a tubular shape, constituting the tubular section; machining the proximal end of the blank to form the attachment section, or attaching an attachment element to the proximal end to form the attachment section.

14. The method of claim 13, wherein a surface of the flat section is machined, and/or one or more holes are created and/or one or more notches are created before the flat section is formed.

15. The method of claim 13, wherein a surface of the flat section is machined, and/or one or more holes are created and/or one or more notches are created after the flat section is formed.

16. A robotic system, configured to be equipped with a cutting tool according to claim 1, the robotic system being programmed to apply the tool to machine an object or workpiece.

17. The robotic system according to claim 16, comprising a manipulator arm to which the tool is attached and by which the tool is movable, and wherein the tool is provided with cooling fluid through the manipulator arm, in particular wherein a cooling fluid conduit is arranged inside a casing of at least one most distal link of the manipulator arm.

18. The robotic system according to claim 16, programmed to apply the tool to machine the workpiece in an uninterrupted sequence, without withdrawing the tool from a region in which it is applied to the workpiece.

19. The robotic system according to claim 18, programmed to apply the tool to machine the workpiece using two or more different functions of the tool without withdrawing the tool, in particular wherein the functions are cutting, sawing filing, and aspiration of material.

20. The robotic system according to claim 16, programmed to apply the tool to machine different sides of the workpiece, in particular surfaces of the workpiece whose surface normal are oriented at an angle of more than forty-five degrees or more than ninety degrees relative to one another.

21. The robotic system according to claim 16, programmed to apply the tool to machine the workpiece in an uninterrupted sequence of at least two minutes or three minutes or four minutes or five or six minutes.

22. The robotic system according to claim 16, wherein the tool is shaped to comprise the function of at least two of a file, a saw, or a knife.

23. The robotic system according to claim 22, wherein the tool is shaped to comprise at least two variants of the same function but with different parameters.

24. The robotic system according to claim 16, comprising a sensing unit configured to measure a tool force exerted by the tool on the workpiece, and being configured to control a movement of the tool according to the measured tool force.

25. The robotic system according to claim 16, configured to provide cooling fluid to the tool intermittently, in particular with first time durations in which cooling fluid is provided alternating with second time durations in which no cooling fluid is provided, in particular wherein a time period after which the first time durations occur lies between one and ten seconds, in particular between two and five seconds.

26. The robotic system according to claim 16, comprising a sensing unit configured to measure a tool temperature and a control unit configured to control a flow of cooling fluid to the tool according to the measured tool temperature.

27. The robotic system according to claim 26, wherein the sensing unit is configured to determine the tool temperature on the basis of a driver frequency of oscillation of the tool, the driver frequency of oscillation being continuously adapted to an actual resonance frequency of the tool.

28. Robotic system according to claim 16, configured to control a flow of cooling fluid to the tool according to an actual operating frequency of the ultrasound driver.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0069] The subject matter of the invention will be explained in more detail in the following text with reference to exemplary embodiments which are illustrated in the attached drawings, which schematically show:

[0070] FIG. 1 a perspective view of a blade;

[0071] FIG. 2 a longitudinal cross section of the blade;

[0072] FIGS. 3-4 a transverse section and an elevated view of a flat section of the blade according to one embodiment.

[0073] FIGS. 5-8 sections and elevated views of further embodiments;

[0074] FIGS. 9-10 further embodiments in an elevated view; and

[0075] FIG. 11 yet a further embodiment in a cross section.

DETAILED DESCRIPTION OF THE INVENTION

[0076] In principle, identical parts are provided with the same reference symbols in the figures.

[0077] FIG. 1 shows a perspective view of a blade 10, and FIG. 2 a longitudinal cross section of the blade. The blade 10 includes a flat section 11, being the working section, connected via a transition section 12 to a tubular section 13, which in turn is connected to an attachment section 14. The flat section 11, transition section 12, tubular section 13 and optionally also the attachment section 14 can be formed from a single tubular blank.

[0078] In the flat section 11, the former lumen of the tube forms a longitudinal channel 20, which can be used to guide, distribute and dispense coolant provided via the tubular section 13. A longitudinal conduit 32 is arranged to supply coolant through the attachment section 14 to the tubular section 13.

[0079] By means of the attachment section 14, the blade 10 can be attached to an ultrasonic vibration generator, for example by means of an outer thread 15, as shown, or an inner thread.

[0080] The transporting and dispensing of the fluid can be enhanced or facilitated by a pumping effect caused by ultrasonic oscillations of the blade 10 and in particular the flat section 11 and/or the transition section 12.

[0081] FIGS. 3-4 show a transverse section and an elevated view of a flat section of the blade 10 wherein a longitudinal weld line 24 creates separate channels 20. The principal surface of the flat section 11 includes structured surfaces 23 such as teeth or grooves. The 8-shape of the transverse section can be obtained when flattening the tube, even if it is not welded afterwards.

[0082] Generally, a first longitudinal edge 25, second longitudinal edge 26 and front edge 27 can be shaped differently or in the same way, with notches 21, teeth, serrations or as blades, or with a combination of these and even other elements.

[0083] FIGS. 5-6 show a transverse section and an elevated view of a flat section of the blade 10 wherein holes 22 are present, constituting openings to the channel 20. Edges of the holes can have a cutting effect. The diameter of the holes 22 is varied in the longitudinal direction in order to control the distribution of the flow of coolant along the length of the flat section 11. This can serve to evenly distribute the flow.

[0084] FIGS. 7-8 show a transverse section and an elevated view of a flat section of the blade 10 wherein notches 21 are present in one or more of the first edge 25 and/or second edge 26 and/or front edge 27. The notches 21 serve on the one hand as serrations for cutting, and on the other hand as conduits guiding coolant out of the channel 20.

[0085] FIGS. 3 to 8 show elements such as weld line 24, structured surface 23, holes 22 and notches 21 separately. In other embodiments, they are combined. For example, according to FIG. 9, notches 21 are present at a first edge 25, holes 22 are arranged near a second edge 26, and the second edge 26 can be shaped as a cutting edge.

[0086] In further embodiments, two or more weld lines 24 are present, creating a corresponding number of channels 20 between them. Weld lines 24 can be used to stiffen the structure of the flat section 11 and thereby modify its natural frequency of oscillation. FIG. 10 shows weld lines 24 distributing coolant to outlets, which in this case are notches 21.

[0087] FIG. 11 shows a further embodiment, with an inner tube 33 that originally was arranged concentrically in the blank and after flattening constitutes a separate longitudinal channel in the blade 10 and in particular in the flat section 11.

[0088] Cutouts such as holes 22 and notches 21 can be machined, for example, by stamping or laser cutting. Other, smaller structures, such as the structured surface 23, can be created by laser engraving or etching. Cutouts and the other structures can be created on the blank, before flattening the blank to form the flat section 11, or afterwards.

[0089] The structured surface 23 and/or the notches 21 can be created in the process of flattening the blank to form the flat section 11.

[0090] The blade 10 can include separate channels. The separate channels can be used for evenly distributing coolant along the flat section 11. Alternatively or in addition, they can be used for different purposes: at least one coolant channel can be used for providing coolant to the flat section 11, and at least one suction channel can be used for sucking material from the region surrounding the flat section 11.

[0091] Separate channels can be formed by one or more weld lines 24 that join opposite sections of the flat section 11, as shown in FIG. 3. Separate channels can be formed by an inner tube 33 arranged inside the blade 10 and extending in its longitudinal direction, as shown in FIG. 11.

[0092] In a specific embodiment, a stainless steel tube with an outer diameter of 4 millimetres and an inner diameter of about 3.5 millimetres is connected with a press fit to an attachment section 14 made of titanium. The attachment section 14 has a thread 15 of dimension M4, that is, with an outer diameter of 6 millimetres. The overall length of the blade 10 is about 100 millimetres, the thickness of the flat section 11 is about 0.9 millimetres. The blade 10 can be operated with an ultrasound driver having an operating frequency of 26 kHz. The blade itself has a resonance frequency of about 26 kHz.

[0093] This frequency relates to longitudinal oscillations, thus oscillations in the direction of the longitudinal axis of the blade 10 as a whole and the flat section 11 in particular.

[0094] While the invention has been described in present embodiments, it is distinctly understood that the invention is not limited thereto, but may be otherwise variously embodied and practised within the scope of the claims.