Title of Invention	AN APPARATUS FOR THE CYLINDRICAL GRINDING OF A WORKPIECE
Abstract	An apparatus for the cylindrical grinding of a workpiece, having a grinding wheel and a receptacle for the workpiece to be ground, characterized in that a deburring pin is provided, and this deburring pin can be pressed onto a neighbouring surface adjoining the surface to be machined of the workpiece.

Full Text

Grinding method and grinding machine Prior art The invention relates to a method for the cylindrical grinding of a workpiece, in which a rotating grinding wheel is fed in towards a surface to be machined of the workpiece, while at the same time the workpiece rotates about its longitudinal axis, the surface to be machined being defined by an edge and merging into a neighbouring surface. The invention also relates to an apparatus for the cylindrical grinding of a workpiece, having a grinding wheel and a receptacle for the workpiece to be ground. A burr which starts from the surface to be ground and extends beyond the edge towards the adjoining neighbouring surface of the workpiece is produced during the grinding operation. If this burr is troublesome for the subsequent function of the finish-machined workpiece, it must be removed by a separate deburring operation. The object of the invention consists in improving the grinding method of the type mentioned at the beginning to the effect that the deburring operation can be dispensed with. Furthermore, the object of the invention is to provide an apparatus for grinding which enables the separate deburring operation to be dispensed with. Advantages of the invention The method according to the invention, having the features of Patent Claim 1, has the advantage that the burr produced when the grinding wheel is fed in towards the surface to be ground is removed automatically. A separate deburring operation is therefore no longer necessary. According to a preferred embodiment of the invention, provision is made for the deburring pin to be set in such a way that it projects outwards beyond the neighbouring surface and the edge towards the surface to be machined. With this orientation of the deburring pin, it is ensured that the burr produced during the grinding is pressed back again completely onto the surface to be ground. Provision is preferably made for the deburring pin to be pressed onto the neighbouring surface with a force of between 10 and 100 N, in particular with a force in the order of magnitude of about 50 N. The said forces constitute a good compromise between reliable pressing-back of the burr on the one hand and low friction forces on the other hand. The apparatus according to the invention, having the features of Patent Claim 6, offers essentially the same advantages as explained with regard to the method according to Claim 1. Since the burr is continuously ground off again by means of the grinding machine according to the invention, a burr-free ground workpiece is produced without a separate machining step following the grinding operation. According to a preferred embodiment of the invention, a pneumatic cylinder is provided, and this pneumatic cylinder can press the deburring pin with an adjustable force against the workpiece to be machined. In this way, with little effort, the contact force between the workpiece and the deburring pin can be set to the respective requirements. Drawings The invention is described below with reference to various exemplary embodiments which are shown in the attached drawings, in which: Fig, 1 shows a grinding machine according to the invention in a schematic view; Fig. 2 shows a detail of Fig. 1 on an enlarged scale; Fig. 3 shows a view of the components shown in Fig. 2 in the direction of arrow III in Fig. 2; Fig. 4 shows a half section through the workpiece to be machined along the plane IV in Fig. 3; Fig. 5 shows a half section through the workpiece to be machined along the plane V in Fig. 3; Fig. 6 shows a second embodiment of the invention in a view in accordance with that of Fig. 2; Fig. 7 shows a section through the workpiece in Fig. 6 in a view in accordance with that of Fig. 4; and Fig• 8 shows a further section through the workpiece in Fig. 6 in a view in accordance with that of Fig. 5. Description of the exemplary embodiments A machine according to a first embodiment of the invention is shown in Fig. 1. The grinding machine contains a frame 10 in which a receptacle 12 for a workpiece 14 to be machined is arranged. A drive 16 with which the workpiece 14 can be set in rotation is provided. Furthermore, a grinding wheel 18 is provided, and this grinding wheel 18 can both be set in rotation and suitably fed in towards a surface to be ground of the workpiece 14 by means of an infeed drive 20. The grinding machine described up to this point is of conventional construction, so that its design need not be described in detail. The grinding machine is additionally provided with a deburring pin 22, which is made of carbide and can be pressed by a pressure mechanism 24 against the workpiece 14 to be machined. The pressure mechanism has a pneumatic cylinder 2 6 (see Fig. 2) , the interior space of whi-ch can be pressurized via two schematically shown pneumatic lines 28 in order to press the deburring pin 22 against the workpiece 14 in the direction of arrow P in Fig. 2. The deburring pin functions as follows: when the grinding wheel 18 is fed in towards a surface 30 to be ground of the workpiece 14 in the direction of arrow Z in Fig. 2, a burr 32 is produced (see Figures 3 and 4), this burr 32 consisting of material which is displaced via an edge 34, which defines the surface 30 to be machined of the workpiece, onto an adj oining neighbouring surface 36. Since the workpiece 14 rotates, the burr reaches the deburring pin 22, which in the embodiment shown is arranged approximately opposite the grinding wheel 18. The burr is pressed back onto the surface 3 0 to be ground by the end face of the deburring pin 22, this end face being designed as a flat pressure surface 3 8, extending perpendicularly to the longitudinal axis of the deburring pin and projecting beyond the edge 3 4. This can clearly be seen by comparing Figures 4 and 5. Fig. 4 shows a section through a segment of the workpiece which has just been machined by the grinding wheel 18 and is now rotating towards the deburring pin 22. The burr 32 is located outside the surface 30 to be machined in the region of the neighbouring surface 36 adjoining the edge 34. A section through a segment of the workpiece can be seen in Fig. 5, this segment moving again towards the grinding wheel 18 after contact with the end face of the deburring pin 22. It can clearly be seen that the burr 32 is pressed back onto the surface 30 to be machined, so that it is ground off during the next contact with the grinding wheel 18. The pressure force of the deburring pin 22 may be selected as a function of the respective requirements and the material to be machined. For example, if the workpiece 14 is a valve needle for a fuel-injection valve for internal combustion engines, in which valve needle the surface to be machined has a diameter of a few millimetres, pressure forces of 50 N are sufficient. The cycle described here, consisting of the production of the burr by contact between the workpiece 14 and the grinding wheel 18, of the pressing-back of the burr 32 onto the surface 30 to be machined, and of the grinding-off of the burr, is repeated until the grinding wheel sparks out, that is to say no more material is removed and consequently no burr can be produced either. The result of the grinding operation described is a workpiece 14 having a ground surface 3 0 which has no burr, without a separate grinding operating having been necessary. The arrangement shown here of the deburring pin 22 relative to the grinding wheel 18 can be varied in accordance with the requirements. If a plurality of surfaces are ground simultaneously and measuring tools, for example, additionally monitor the grinding operation, the deburring pin 22 can also be set in other positions relative to the grinding wheel. A second embodiment of the grinding machine and of the grinding method carried out with it is shown in Figures 6 to 8. The same reference numerals are used for components already known from the first embodiment, and reference is made to the above explanations. The most important difference from the first embodiment consists in the fact that a cylindrical outer surface of the workpiece 14 is ground here, so that the burr 32 is produced on a neighbouring surface 36 adjoining the surface 30 to be machined, this neighbouring surface 3 0 extending perpendicularly to the longitudinal axis of the workpiece 14. From this neighbouring surface 36, the burr 32 is pressed back again by the deburring pin 22 onto the surface 3 0 to be ground, as can be seen by comparing Figures 7 and 8. Unlike the first embodiment, the deburring pin 22 in the second embodiment does not bear with its end face against the workpiece 14 but with a conical pressure surface 38. In addition, the longitudinal axis of the deburring pin 22 is not oriented perpendicularly to the longitudinal axis of the workpiece 14 but extends at an angle to the latter. It is especially worth mentioning that the deburring pin 22 is not pressed against the workpiece 14 approximately in the direction in which the burr 32 is to be pressed back onto the surface to be machined, but in a direction in which it would be expected that the burr would be pressed further inwards towards the longitudinal axis of the workpiece. However, the pressure surface 38 set at an angle actually presses the burr 32 away from the longitudinal axis of the workpiece 14 onto the surface 30 to be machined. The orientation shown here of the deburring pin 22 is especially advantageous if other components of the grinding machine have to be arranged in the region lying on the left of the deburring pin 22 with respect to Fig. 6; in this arrangement, the pressure mechanism 24 may then be arranged well outside this region. Patent claims 1. Method for the cylindrical grinding of a workpiece (14), in which a rotating grinding wheel (18) is fed in towards a surface (30) to be machined of the workpiece, while at the same time the workpiece rotates about its longitudinal axis, the surface to be machined being defined by an edge (34) and merging into a neighbouring surface (36) , characterized in that a deburring pin (22) is pressed onto the neighbouring surface (3 6) during the grinding, so that a burr (32) produced during the grinding of the surface to be ground is pressed back onto the latter. 2. Method according to Claim 1, characterized in that the deburring pin (22) is set in such a way that it projects outwards beyond the neighbouring surface (36) and the edge (34) towards the surface (30) to be machined. 3. Method according to Claim 2, characterized in that the deburring pin (22) is set in such a way that it projects with approximately half its diameter beyond the neighbouring surface (36). 4. Method according to one of Claims 1 to 3, characterized in that the deburring pin (22) is pressed onto the neighbouring surface (36) with a force of between 10 and 100 N. 5. Method according to Claim 4, characterized in that the deburring pin (22) is pressed onto the neighbouring surface with a force of about 50 N. 6. Apparatus for the cylindrical grinding of a workpiece (14), having a grinding wheel (18) and a receptacle (12) for the workpiece (14) to be ground, characterized in that a deburring pin (22) is provided, and this deburring pin (22) can be pressed onto a neighbouring surface (36) adjoining the surface (30) to be machined of the workpiece (14) . i 7. Apparatus according to Claim 6, characterized in that the deburring pin (22) has a flat end face. 8. Apparatus according to Claim 6, characterized in that the deburring pin (22) has a conical pressure surface (38) . 9. Apparatus according to one of Claims 6 to 8, characterized in that the deburring pin (22) is arranged in such a way that its longitudinal axis extends approximately at a right angle to the longitudinal axis of the workpiece (14) to be machined. 10. Apparatus according to one of Claims 6 to 8, characterized in that the deburring pin (22) is arranged in such a way that its longitudinal axis extends at an angle differing from 90° relative to the longitudinal axis of the workpiece (14) to be machined. 11. Apparatus according to one of Claims 6 to 10, characterized in that a pneumatic cylinder (26) is provided, and this pneumatic cylinder (26) can press the deburring pin (22) with an adjustable force against the workpiece (14) to be machined. i'2. Method for the cylindrical grinding of a workpiece substantially as hereinbefore described with reference to the accompanying drawings. 13. Apparatus for the cylindrical grinding of a workpiece substantially as hereinbefore described with reference to the accompanying drawings.

Documents:

in-pct-2001-1412-che-abstract.pdf

in-pct-2001-1412-che-claims filed.pdf

in-pct-2001-1412-che-claims granted.pdf

in-pct-2001-1412-che-correspondnece-others.pdf

in-pct-2001-1412-che-correspondnece-po.pdf

in-pct-2001-1412-che-description(complete) filed.pdf

in-pct-2001-1412-che-description(complete) granted.pdf

in-pct-2001-1412-che-drawings.pdf

in-pct-2001-1412-che-form 1.pdf

in-pct-2001-1412-che-form 26.pdf

in-pct-2001-1412-che-form 3.pdf

in-pct-2001-1412-che-form 5.pdf

in-pct-2001-1412-che-other documents.pdf