DE7439613U - Auxiliary device for regrinding drills - Google Patents

Description

Auxiliary device for regrinding drills

The invention relates to an auxiliary device for facilitating regrinding with manual on a rotating grinding wheel held drills, in particular high-speed steel (HSS) twist drills, the device primarily intended for do-it-yourselfers.

Up until now, drill bits that had become blunt were largely thrown away by do-it-yourselfers, as there was hardly any possibility of to regrind the drills with the required accuracy. Occasionally it has already been undertaken, the drills at manual adjustment and holding on to a stationary rotating grinding wheel, however it was only possible for very skilled do-it-yourselfers. the drill tip with a correct roof angle and back grind to provide.

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The invention is based on the object of providing the do-it-yourselfer a to provide inexpensive, easily manageable auxiliary device for regrinding drills through which correct adherence to the roof angle and the required relief grinding is ensured.

The solution to this problem is characterized according to the invention by means of a forked support body that can be placed on the grinding wheel shaft or hub under the frame of the grinding wheel, on the back of the gobel there is a round opening in the fork Groove open on both sides for inserting the drill is arranged, which is shorter than the drill. According to the invention is here - seen in plan view - the groove in a dimension corresponding to the cutting edge or roof angle of the drill inclined towards the fork arms · Furthermore, care is taken that the groove, and thus the »drill When the support body is placed on the grinding wheel shaft, it is eccentric to the grinding wheel - i.e. always parallel to the Diametrical plane of the grinding wheel - is directed, whereby <a correct relief grinding is ensured.

The required eccentric alignment of the groove can be constructive can be achieved in several ways. According to one embodiment, on both sides of the grinding wheel on the SchleifscheJjDenwelle hubs or rings can be provided to support the fork arms, so that those of the Gaoelarm

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defined support level - and thus the one in or above ί drills to be reground lying on this level - inevitable always maintains the same distance from the diametrical plane of the grinding wheel that is parallel to the support plane. Alternatively can this eccentric position of the groove or the inserted Drill, can also be ensured by shaping the support body by, according to the invention, the support surfaces the plane containing the fork arms and the parallel plane defined by the groove base have a clear distance from one another have what z. B. by crimping the fork ends can be implemented constructively below.

According to a preferred embodiment, the fork back is of the forked support body as a plate that can be held between the index finger and thumb of one hand in the area of the groove According to the invention, the groove has a triangular profile, so that the drill, regardless of its diameter, finds a perfect edition. The drill is operated with the thumb of the generally left hand gripping the plate held in the groove, and with the other hand the Drill gripped at its rear end protruding from the groove and constantly around its during regrinding Rotated longitudinal axis. Because the mentioned oblique orientation and the eccentric orientation of the inserted into the groove Drill are fixed by the auxiliary device and also when pivoting the auxiliary device around the grinding

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Disc axis hevum remain unchanged, the device according to the invention ensures regrinding with correct cutting angle and relief grinding.

To protect the fingers reaching under the plate from slipping off, the plate can have the fork base at its base Side a finger protection edge protruding downwards own. Finally, according to the invention, one can also be mounted on the fork back, via the groove or via the therein have inserted drill, swiveling clamping bracket, which is pressed down by the thumb of the gripping hand on the ear, so that the thumb only indirectly holds the drill in its groove.

Dor GotfoniifcMnil dur KrfJmhinK is in the folRondon rujhnnd the Drawing explained in more detail in which show: #

1 shows a perspective overall view to explain the construction and handling of the auxiliary device according to the invention,

2 shows a plan view of the auxiliary device according to the invention,

Fig. 3 shows a section along the line III-III in Fig. 2,

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♦ Jr. I J * J

⁽ J

J J

Pig. 4 shows a section along the line IV-IV in FIG. 2,

Piss. 5 shows a side view of the auxiliary device a drill adjusted to a grinding axis.

Fig. 1 shows a forked support body "I, the fork back 2 consists of a plate and its two fork arms 3 »4 consist of two dog material rods attached to the fork back 2, which sized one to tightly enclose a grinding wheel 5 " Have a distance from each other. The grinding wheel shaft 6 carries 5 rings or hubs on the side of the grinding wheel 7 and 8 of larger diameter, on which the fork arms 3, 4 rest with their underside.

The plate-shaped fork back 2 is profiled on its upper side with an open at both ends, triangular in cross-section Groove 9 (see also FIGS. 2 to 4) is provided, which lies in a plane parallel to the GabeDormen 3 »4, but which in Draiif sees (according to Fig. 2) opposite the fork arms' 3, 4 is oriented obliquely. The groove 9 is used for recording a drill 10 to be reground, which is for example It is an HSS twist drill that does not have carbide cutting edges at its tip. the The device according to the invention is basically also suitable for hard metal fittings Drill can be used, but a diamond grinding wheel would have to be provided in such a sleeve.

The handling of the device is as follows: The drill 10 to be re-sharpened is inserted into the groove 9 opening in the fork base 11 in such a way that its tip protrudes a short distance, the plate-shaped fork rump 2 being grasped with the left hand in the manner shown Fingers of the left hand grasp the plate, being protected against slipping by a downwardly protruding edge 12 provided on the side of the fork base 11 on the fork back 2, while the thumb of the left hand reads the top of the fork back 2 and the drill 10 holds in the groove. The fork-shaped support body 1 is then placed under the frame of the grinding wheel 5 with its fork arms 3, 4 on the hubs 7, 8 of the stationary grinding wheel and then pushed up to the point of the drill bit against the grinding wheel. Then the drill 10 is gripped with the right hand at its rear end protruding from the groove 9 and its longitudinal axis is continuously rotated. The fixed inclined position of the 3 ear 10 gives its tip a perfect roof or cutting edge angle when regrinding. 7 / ie can be seen from Fig. 5, the axis of the Eohrers 10 is at a clear distance E above that parallel to the fork arms. Diametrical plane D of the grinding wheel; the drill is consequently employed eccentrically on the grinding wheel. This distance E, or this eccentricity, determines the relief of the drill cutting edges

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and is maintained unchanged even if the entire Auxiliary device is swiveled up or down around the grinding wheel axis

Distance E and the eccentricity of the drill 10 at the 1st Ausführunßsbeispiel substantially the diameter of the grinding wheel hub 7, 8 dependent. As indicated by dashed lines in FIG. 3 ', this distance E can also be achieved constructively by a bend 4' of the fork ends 3, 4.

As shown in FIGS. 2 and 4, a pivotably mounted fork back can be mounted on the plate-shaped fork back and via the groove 9 gripping clamping bracket 13 are provided, which is used to hold down the drill 10 inserted into the groove 9 and the is pressed on the drill 10 with the thumb of the left gripping hand while grinding. Preferably there is the clamping bracket 13 ice plastic.

As can also be seen from FIGS. 2 and 3, the fork back is provided in the region of its fork base 11 with a downwardly widening recess 14, approximately triangular in cross section, for receiving the grinding wheel 5, so that the fork back 2 fits very closely the grinding wheel circumference can be pushed in »

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Claims (1)

Expectations 1. Auxiliary device to facilitate each grinding beljmanuell held on a rotating grinding wheel Drills, especially HSS twist drills, marked by means of one that can be placed on the grinding wheel shaft (6) or hub (7, 8) under the frame of the grinding wheel (5), Forked support body (1), on the fork back (2) above a fork base (11) opening out at both ends open groove (9) for inserting the drill (10) is arranged, which (9) is shorter than the drill. 2 · Device according to claim 1, characterized in that that - seen in plan view - the groove (9) in a dimension corresponding to the cutting angle of the drill (10) is inclined in relation to the fork arms (3 »^) Device according to Claims 1 and 2, characterized in that the groove (9) is eccentric to the grinding wheel axis is oriented. Device according to Claim 3, characterized in that rings or hubs (7, 8) for supporting the fork arms (3, ⁷ O) are provided on both sides of the grinding wheel (5) on the grinding wheel shaft (6). '439613 07.0175 5. Device according to claim 3, characterized in that that the support surfaces of the fork arms (3, 4) contain The plane and the parallel plane defined by the groove base are at a distance o 6 · Device according to one of claims 1 to 5 »thereby characterized in that the fork back (2) as one in the region of the groove (9) between the index finger and thumb Hand-grippable plate is formed. 7 · Device according to one of claims 1 to 6, characterized characterized in that the groove (9) has a triangular profile. 8. Apparatus according to claim 6, characterized in that that the plate-shaped fork back (2) on its side having the fork round (11) one downwards protruding fincer protection edge (12) has " 9 · Device according to one or more of the preceding Claims, characterized by one on the fork back (2) mounted, swiveling clamping bracket (13) via the groove (9) or a drill bit (10) inserted therein 7439813 05/07/75