Title of Invention

LASER HONING TOOL FOR GENERATING A STRUCTURE FORMED BY MICRO-BAGS ON A TRIBOLOGICALLY STRESSED SURFACE OF A WORK-PIECE

Abstract

Laser honing tool for generating a structure formed by micro-bags (6) on a tribologically stressed surface (3) of a work-piece (1) with: (a) agents (78) for connecting the lower open hollow end (9) of a spindle (10) on to a tool body (5) of the laser honing tool, and for introducing a laser beam (15) into the inner space (16) of the tool body (5); (b) agents (17) for focusing the laser beam (15); (c) agents (18, 18') for deflecting the laser beam (15) by about 90°; (d) a replaceable laser beam exit module (30), into which the laser beam (15) ios introduced through a protective glass (31) and from which it again exits through an opening (32), whereby between the protective glass (31) and the opening (32) a space (35) is designed, to which a gas is fed through a line (40), which again flows out of the space (35) through the opening (31).

Full Text

Laser Honing Tool for Generating a Structure Formed by Micro-bags on a Tribologically Stressed Surface of a Work-Piece Description The invention pertains to a laser honing tool for generating a structure formed by micro- bags on a tribologically stressed surface of a work-piece. Such a surface could, for example, be the cylindrical contact surface of a bore in the engine block of a combustion engine. The micro-bags serve the purpose of a receiving lubricant, particularly in the region of the upper and lower dead centres of the piston of the combustion engine. Laser honing tools with agents for introducing, focusing and deflecting a laser beam are known (EP 0 565 724 B1; DE 43 16 012 C2; DE 295 06 005 U; EP 1 275 864 B1). It is the task of this invention, to further improve such laser honing tools. This task is fulfilled as per the invention with the help of agents as mentioned in claim 1. The invention further pertains to various advantageous extensions. Design example of the invention and their advantageous extensions are described in more details below on the basis of the enclosed drawings. The following are shown: Fig. 1 A design example; Fig.2 A second design example; Fig.3 A trimming and fine-honing tool used subsequent to the processing, with the design example as shown in figures 1 and 2. Figure 1 shows a work-piece 1 with a bore 2, which has a cylindrical inner surface 3. Micro-bags 6 are introduced into this inner surface 3 with the help of a laser beam; these micro-bags receive lubricants in case of a tribological stressing (stressing due to friction) of the inner surface 3, e.g. the cylindrical bore in the engine block of a combustion engine. The laser honing tool has a tool body 5, which is fixed with bolts 7 on to a flange 8 of the hollow spindle 10 of a honing machine that is open below. The spindle can be moved up and down and can also be rotated. The laser beam 15 is generated with known agents and introduced on top (not shown) into the hollow inner space 11 of the spindle 10. It then comes out of the opening 9 at the lower end of the spindle 10 and enters the inner space 16 of the tool body 5 and is focused by a focussing lens 17 in such a way, that after deflection by the deflecting mirror 18' of a deflecting mechanism 18 and on meeting the inner surface 3 of the work- piece 1 it forms the point P. If the spindle 10 is then rotated around its axis A by a certain angle, one obtains a micro-bag 6. The focussing lens 17 is situated in a sleeve 20 that is arranged in the tool body and can be axially shifted but not rotated. This is achieved, in that a pin 23 fixed to it is guided in a slit 22 running in axial direction. Focussing is done by rotating a setting ring 19, which is arranged on to the tool body 5, and can be rotated but not axially shifted. The setting ring 19 is provided on the inside with a rectangular, spiral-shaped groove 21 that runs at an inclination, like a thread against the axis A, into which the pin 23 grips in. As this is fixed to the sleeve 20, on rotating the setting ring 19 there results an axial shift of a pin 23 and hence also of the sleeve 20 with the focussing lens 17 connected to it. After getting deflected by the deflecting mirror 18', the laser beam 15 runs through a laser exit module 30, in which a protective glass 31 is arranged. This helps in preventing dirtying of the inner space 16 by particles that get carried away while the laser beam 15 acts on the inner surface 3, and get sprayed from the inner surface 3. The laser beam 15 exits from the laser exit module 30 through the opening 32. The diameter of the opening 32 should be as small as possible, however larger than the beam diameter at this point, in order to also contribute towards preventing any particles entering into the space 35 between the protective glass 31 and the opening 32. A further measure for keeping the surface of the protective glass 31 towards the opening 32 clean, is by introducing a gas under pressure into the space 35 between the protective glass 31 and the opening 32 through a line 40; this gas then again exits through the opening 32 out of the space 35, so that this flow similarly prevents penetration of particles blown off from the inner surface 3 on account of the laser effect, on the side of the protective glass 31 away from the inner surface 3. Displacement of the setting ring 19 can either be done manually or by a NC-controI to different diameters of the bore 2. The deflecting mechanism 18 has, as has been shown, a deflecting mirror 18' that reflects the laser light. However, it can also be designed as a prism, so that the laser beam 15 gets deflected on account of the laws of total reflection. The deflecting mechanism 18 is adjustable, among other things because the deflecting mirror 18' can be swivelled around the axis B running perpendicular to the drawing plane. Furthermore, the deflecting mechanism including the axis B on the base 25, can be rotated around the axis A. Due to variations during adjusting of the laser beam 15, there could be variations with respect to the deflecting angle as against exactly 90°, and in the diameter of the laser beam while passing through the opening 32. If the laser beam 15 is not aligned exactly centric to the tool body 5, then it strays up and down on rotation of the tool body 5. In case of a slanting arrangement, as indicated only schematically in the design example shown in figure 2, further variations occur. If in spite of the measures taken, the protective glass 31 is dirty, then the laser exit module 30 can be replaced in a very simple manner. This quick and adjustment-free replacement possibility reduces the standstill periods in production. The laser honing tool 5 is preferably positioned in the centre of the bore 2 in such a way, that it can be rotated around the axis A. In this way, the distance between the focusing lens 17 and the inner surface 3 and hence the focussing plate in which the point P lies, remains constant. One can also position the laser honing tool eccentric to the axis of the bore 2 and rotate it. In this way the distance between the inner surface 3 and the laser honing tool increases. For this however, the laser honing tool 5 must simultaneously be guided on a circular path. Alternatively, it is also possible to let the work-piece 1 rotate around the laser honing tool 5. In a design example, as shown in figure 2, the laser beam 15 is introduced at an inclination from outside on the top into the bore 2. The laser honing tool is thereby positioned outside the bore 2. In that case, a deflection of the laser beam 15, as shown in figure 1, does not take place. The processing takes place in such a way, that a bore 2 is initially pre-honed in the usual way. Then with the help of the described laser-honing tool, the structure formed by the micro-bags 6 is brought in. Subsequently the inner surface 3 is trimmed in a further work sequence, i.e. freed from the burrs on the edges of micro-bags 6, and then finish-honed. Trimming and finish-honing can be done with the help of a single trimming and honing tool, which is designed as a double flaring tool as shown in figure 3. It has a tool body 51 which is provided with radial slots, into which - alternately - first honing cleats 52 with short cutting planks 60 for stripping, and second honing cleats 53 with long cutting planks 61 for finish-honing are arranged. The short honing cleats 52 help to strip the edges of the micro-bags 6 in the region close to the upper dead centre of a piston that is arranged in a bore 2 of a combustion engine, can be moved up and down. The short honing cleats 52 help to strip the edges of the micro-bags 6. For that, only short honing cleats are required, if for example micro-bags have been attached only in the upper region (near the upper dead centre of a piston) on the inner surface 3. If one shifts the flaring rod 54, on which conical/tapered faces 54' are foreseen, which work along with conical/tapered faces 52' on the honing cleats 52, then the honing cleats 52 get pushed radially outwards. Now stripping can be done. However, if one shifts the flaring rod 55, which is foreseen with conical/tapered faces 55' that work along with the conical/tapered faces 53' on the second honing cleats 53, then the second honing cleats 53 get pushed radially outwards. Then final honing is done. During upward movement of the flaring rods 54 or 55, the honing cleats 52 or 53 are drawn radially inwards by return springs 56. WE CLAIM 1. *A laser honing tool for generating a structure formed by micro bags (6) on a tri-biologically stressed surface (3) of a word piece (1) comprising:- a hollow cylindrical body member (5) agent (7,8) for connecting the lower open end (9) of a spindle (10) on to tool body (5) of the laser honing tool and for introducing a laser beam (5) into the inner space (16)of the tool body (5); the tool body (5) provided with a sleeve (20) axialy movable by means of a pin (23) fixed to it guided in slit (22); agent (17) for focusing the laser beam (15) by rotating a setting ring (19) provided in the lnner hollow part of tool body (5); agent (18,160) for deflecting the laser beam (15) by about 90°; a replaceable laser beam exit module (30), into which the laser beam (15) is introduced through a protective glass(31) and from which it again exits through an opening (32) where by between the protective glass (31) and the opening (32) a space (35) is designed , to which a gas is fed through a line (40), which again flows out of space (35) through the opening (31) Characterized in that the honing tool is capable of performing multidirectional cutting activity." 2. Laser honing tool for generating a structure formed by micro bags (6) on a tribologically stressed surface (3) of a work piece as claimed in claim 1 wherein a) agents (78) for connecting the tower open hollow end (9) of a spindle (10) on to a tool body (5) of the laser honing tool and for introducing s laser beam (15 into the inner space (16) of the tool body (5); b) agent (17) for focussing the laser beam (15); c) a replaceable laser beam exit module (30), into which the laser beam (15) is introduced through a protective glass (31) and from which it again exits through an opening (32), whereby between tht preconceive glass (31) and the opening (32) a space (35) is designed, into which a gas is fed through a line (40), which again flows out of the space (35) through the opening (31). and the amendment claim 6 to read as "method for introducing micro- bag (6) in tribologlcally stressed cylindrical inner surface (3) in work pieces (1) as claimed in claim 1"where in especially into the contact surface of cylindrical bores of combustion engines, in which the following steps are involved :- (a) pre-honing in the inner surface (3) with a known honing tool; (b) bringing in the structure of micro-bag (6) with the help of a laser honing tool according to one of the claims 1 -5; (c) stripping of the edges of the micro-bags (6); finish-honing of the inner surface (3). 3. Laser honing tool as claimed in claim 1 or 2, wherein the focussing lens (17) in the tool body (5) is arranged in a sleeve (20) that can be axially shifted, which has a pin (23) stretching through a slot (22) in the tool body; this pin (23) is guided in an inclined running roove (21) of a setting ring (19) surrounding the sleeve. 4. Laser honing tool as claimed in one of the claim 1 or 3, wherein the agents (18) for deflecting the laser beam (15) have a deflecting mirror (18) that can be swivelled around an axis (B) which run perpendicular to the axis (A) of the laser honing tool. 5. Laser honing tool as claimed in claim 4, wherein the agents (18) for deflecting the laser beam (15) can be twisted against the tool body (5). 6. Method for introducing micro-bags (6) used in a laser honings tool for generating a structure as claimed in claim 1, in the tribologically stressed cylindrical inner surfaces (3) in work-pieces (1), especially into the contact surfaces of cylindrical bores on combustion engines, wherein the following steps are involved: a) pre-honing in the inner surface (3) with a known honing tool; b) bringing in the structure of micro-bags (6) with the help of a laser honing tool according to one of the claims 1-5; c) stripping of edges of the micro-bags (6); d) finish-honing of the inner surface (3). 7. Method as claimed in claim 6, wherein for stripping (step (c)) and for finish- honing (step (d)) a double flaring tool (50) with independently activate-able first (52) and second (53) honing cleats are used, in which the first honing cleats (52) stretch over the region provided with micro-bags (6) and help the stripping operation, and the second honing cleats (53) stretching over the entire surface help in the finish-honing. 8. Method as claimed in claim 6 or 7, wherein the laser honing tool is rotated in the bore (2) eccentric to the axis (A) of the bore. 9. Method as claimed in claim 6, wherein for bringing in the micro-bags (6) forming the structure, the laser beam (15) is introduced inclined at the top into the bore (2). Laser honing tool for generating a structure formed by micro-bags (6) on a tribologically stressed surface (3) of a work-piece (1) with: (a) agents (78) for connecting the lower open hollow end (9) of a spindle (10) on to a tool body (5) of the laser honing tool, and for introducing a laser beam (15) into the inner space (16) of the tool body (5); (b) agents (17) for focusing the laser beam (15); (c) agents (18, 18') for deflecting the laser beam (15) by about 90°; (d) a replaceable laser beam exit module (30), into which the laser beam (15) ios introduced through a protective glass (31) and from which it again exits through an opening (32), whereby between the protective glass (31) and the opening (32) a space (35) is designed, to which a gas is fed through a line (40), which again flows out of the space (35) through the opening (31).

Documents:

1105-KOL-2005-FORM 27 1.1.pdf

1105-KOL-2005-FORM 27-1.1.pdf

1105-KOL-2005-FORM 27.pdf

1105-KOL-2005-FORM-27-1.2.pdf

1105-kol-2005-granted-abstract.pdf

1105-kol-2005-granted-claims.pdf

1105-kol-2005-granted-correspondence.pdf

1105-kol-2005-granted-description (complete).pdf

1105-kol-2005-granted-drawings.pdf

1105-kol-2005-granted-examination report.pdf

1105-kol-2005-granted-form 1.pdf

1105-kol-2005-granted-form 18.pdf

1105-kol-2005-granted-form 2.pdf

1105-kol-2005-granted-form 26.pdf

1105-kol-2005-granted-form 3.pdf

1105-kol-2005-granted-form 5.pdf

1105-kol-2005-granted-priority document.pdf

1105-kol-2005-granted-reply to examination report.pdf

1105-kol-2005-granted-specification.pdf

1105-kol-2005-granted-translated copy of priority document.pdf