Device and method for generating microstructures in cylindrical surfaces

Patent metadata

Field	Value
Publication number	US-9272341-B2
Application number	US-201313951576-A
Country	US
Kind code	B2
Filing date	Jul 26, 2013
Priority date	Aug 17, 2012
Publication date	Mar 1, 2016
Grant date	Mar 1, 2016

Abstract

Tool and method for generating microstructures within cylindrical surfaces with a higher degree of efficiency, thereby allowing to provide cylindrical surfaces with a corresponding microstructure in much shorter cycle time. Cutting elements of the tool are arranged within seats to be radially displaceable in said seats during rotation of said tool body. The cutting elements are radially displaceable at least between two different radial positions, namely a radially retracted and a radially extended position. The cutting elements can be evenly distributed about the circumference of the tool at the same radial distance such that the tips of the cutting teeth and also the seats define a common cylindrical envelope surface the axis of which coincides with the axis of the tool body.

First claim

What is claimed is:

1. A device for generating microstructures in cylindrical surfaces, comprising:
a tool body rotatable about a tool axis, having at least two seats for cutting elements at circumferentially spaced positions and cutting elements comprising a plurality of micro cutting teeth,
wherein said cutting elements are arranged within said seats such as to be radially and axially displaceable in said seats during rotation of said tool body,
wherein said cutting elements are in the shape of elongate plates comprising cutting teeth at least along one of the longitudinal edges of said plate,
wherein said cutting teeth comprise at least one cutting edge forming an acute angle with the tool axis, and
wherein cutting edges of at least two different cutting elements are provided each of which cutting edges forming an acute angle with the tool axis, the acute angle of a first one of said at least two different cutting elements being oriented towards a first direction relative to the tool axis which is opposite to the orientation of the acute angle of a second one of the at least two different cutting elements.

2. The device according to claim 1 , wherein guiding means are provided in said seats and on said cutting elements imparting an axial component of movement to said cutting elements simultaneously with any radial movement.

3. The device according to claim 1 , wherein said cutting elements are displaceable between at least one radially retracted and one radially extended position.

4. The device according to claim 1 , wherein at least a plurality of said cutting teeth have the same shape and are arranged at a constant pitch.

5. The device according to claim 1 , wherein the cutting teeth of said at least two different cutting elements are arranged with respect to each other along the axial direction such that, upon rotation of said tool about the tool axis, said cutting teeth mutually engage grooves generated by the respective cutting teeth of a respective preceding other cutting element.

6. The device according to claim 5 , wherein the cutting elements of at least one pair of different cutting elements are provided on diametrically opposed sides of the tool body.

7. The device according to claim 1 , wherein the cutting elements of at least one pair of different cutting elements are provided on diametrically opposed sides of the tool body.

8. The device according to claim 1 , wherein said cutting elements are biased towards a retracted position towards the tool body.

9. The device according to claim 1 , comprising radial displacement means in fluid communication with a cooling or flushing channel.

10. The device according to claim 1 , comprising radial displacement means, wherein the radial displacement means are wedge shaped bars forming a radial outer seating surface for the cutting elements and a radially inner sliding surface for sliding along a support surface which is tilted with respect to the tool axis.

11. The device according to claim 10 , wherein the radial displacement means are either hydraulically, pneumatically, mechanically, electrically or electromagnetically driven.

12. The device according to claim 1 , wherein at least three pairs of different cutting elements are arranged alternatingly under uniform angular distances about a periphery of the tool body.

13. The device according to claim 12 , wherein each of the pairs of different cutting elements is arranged at a different axial position than another pair of different cutting elements.

14. The device according to claim 1 , wherein the generated microstructures include grooves having a depth and a width in the cylindrical surface that are less than 1 mm.

15. A method for generating microstructures in cylindrical surfaces of a work piece with the device according to claim 1 .

16. A method for generating microstructures in cylindrical surfaces of a work piece with a tool body rotatable about a tool axis, said tool body comprising at least two angularly spaced seats receiving cutting elements, said cutting elements having a plurality of micro cutting teeth, the method comprising:
aligning the tool axis of said rotatable tool with an axis of said cylindrical surface, while said cutting elements are retracted towards the tool body in an inactive radial position;
arranging the tool body at an axial position with respect to the cylindrical surface corresponding to a position where the cutting elements are to produce the microstructure on said surface; and
during rotation of the tool body, radially extending said cutting elements into an active cutting position and engaging said cylindrical surface to generate said microstructures,
wherein said cutting elements are imparted an additional axial component of movement during the radial movement thereof,
wherein at least two different cutting elements are provided, the cutting edges of which form an acute angle with the tool axis, the acute angle of a first one of said at least two different cutting elements being oriented towards a first direction relative to the tool axis which is opposite to the orientation of the acute angle of a second one of said at least two different cutting elements, wherein the two different cutting elements are imparted an axial component of movement towards opposite axial directions while simultaneously being moved in the radial direction, and
wherein any axial feed of the tool body upon rotation thereof while the cutting elements are in engagement with the work place is adapted to a pitch of the cutting elements such that the cutting teeth of a pair of cutting elements which are arranged at different circumferential positions of the tool body engage the same grooves of the microstructure which have been generated by a preceding cutting teeth of the respective other cutting element.

17. The method according to claim 16 , wherein said cutting elements are biased towards a radially retracted position and are extended towards a radial extended position by applying a pressure of a cooling- or flushing media within the tool body.

18. The method according to claim 16 , wherein a plurality of parallel circumferential circular undercut grooves are generated in parallel without any axial feed of the tool body.

19. The method according to claim 16 , wherein the generated microstructures include grooves having a depth and a width in the cylindrical surface that are less than 1 mm.

20. The method according to claim 19 , wherein a pitch of the grooves is two to three times the groove width.

21. A device for generating microstructures in cylindrical surfaces, comprising:
a tool body rotatable about a tool axis, having at least two seats for cutting elements at circumferentially spaced positions and cutting elements comprising a plurality of micro cutting teeth,
wherein said cutting elements are arranged within said seats to be radially and axially displaceable relative to surfaces of the seat during rotation of said tool body,
wherein said cutting elements are in the shape of elongate plates comprising cutting teeth at least along one of the longitudinal edges of said plate,
wherein said cutting teeth comprise at least one cutting edge forming an acute angle with the tool axis, and
wherein cutting edges of at least two different cutting elements are provided each of which cutting edges forming an acute angle with the tool axis, the acute angle of a first one of said at least two different cutting elements being oriented towards a first direction relative to the tool axis

Assignees

• Walter Ag

Inventors

• Nedzlek Kevin
• Baertson Kenneth

Classifications

• Y10T408/03

  Processes · CPC title

• B23B2270/24

  Tool, chuck or other device activated by the coolant or lubrication system of the machine tool · CPC title

• Y10T408/44

  with means to apply transient, fluent medium to work or product · CPC title

• Y10T408/85

  to move radially · CPC title

• Y10T408/858

  Moving means including wedge, screw or cam · CPC title