DE8910822U1 - Adapter compatible with the work spindle of a hand-held power tool - Google Patents

Description

Lipenf'ia
Patent-Verw.aifujigs-fimbH: . _: **.\-&Ggr;

Theodor-Stern-Kai &idiagr;"" 6*000 Frankfurt 1

WN89/16

Adapter compatible with the work spindle of a hand-held power tool

The innovation relates to an adapter according to the preamble of claim 1.

In such an adapter, the locking element that effects the axial locking of the centering drill is spherical and, together with an enclosing ring spring, effects the axial locking of the centering drill.

It has been shown that such a locking device leaves something to be desired in terms of simplicity and the time required for changing the center drill.

The innovation is based on the task of equipping the generic adapter with a locking device that enables comparatively quicker and easier center drill changes.

This problem is solved according to the invention with the characterizing features of claim 1.

Further developments and expedient embodiments of the innovation are characterized in the subclaims.

The innovation is explained below using the drawing, which illustrates a preferred embodiment of the locking device for a generic adapter.

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Show it:

Fig.: 1 two different versions of an adapter, namely the adapter shown in the lower half of this figure has a threaded hole for accommodating a work spindle with a smaller diameter than the adapter according to the upper half of the figure,

Fig. 2 is a view along section A-A through Fig. 1,

Fig. 3 an adapter according to the upper half of Figure 1 with screwed-on core bit and inserted centering or normal drill.

The adapter 10 shown in the lower half of Figure 1 is designed as a hollow body 11 with a continuous axial bore 12. In the drive-side area, the hollow body has a section provided with an internal thread 13 for receiving a corresponding threaded attachment on the work spindle of a hand-held power tool. The threads that correspond to one another are, for example, 1/2" threads.

Two diametrically opposed rotary drive webs 14 are attached to the inner circumference of the axial bore 12. If necessary, additional rotary drive webs can also be provided in any spatial position relative to one another. In the area facing away from the internal thread 13, the adapter contains a projection 15 provided with an external thread 15', which serves to accommodate a drill bit, which is designated 16 in Figure 3.

Approximately in the middle area of the wall of the hollow body 11 of the adapter, there is at least one radially extending, continuous opening 17 for receiving a roller-shaped locking

elements 18, which is prevented from falling out inwards by a constriction in the mouth area of the through-opening 17 in the axial bore 12. Instead of barrel-shaped locking elements, balls or similarly designed components can also be used.

A sliding sleeve 19 is pushed onto the hollow body 11 of the adapter and is subject to the action of a return spring 20 which is supported on the one hand by a locking ring 21 attached to the drive-side end of the hollow body 11 and with its other end by an annular web 19' of the sliding sleeve. In the rest position, the sliding sleeve 19 rests against a collar-shaped projection 11 ^: of the hollow body 11 and is secured by this against axial displacement towards the output side. In order to prevent dust Gtc. from penetrating the space between the sliding sleeve 19 and the outer wall of the hollow body 11, an O-ring 22 is inserted into a recess in the sliding sleeve 19.

The sliding sleeve 19 has a chamber-like recess 23 on its inner circumference, which expediently extends all the way around.

This recess interacts with the locking element 18 in such a way that the latter can move radially outwards into the recess 23 when the sliding sleeve 19 is pulled back against the restoring force of the spring 20, if the shaft of a centering drill 24 exerts a radial force on the ^part of the locking element protruding into the axial bore 12 when the drill is inserted or removed. This enables a quick change of drill (see Fig. 3).

For sealing and/or holding reasons, an O-ring 26 or similar component can be provided in the axial bore 12 of the adapter at the level of the shoulder 15.

The adapter illustrated in the upper half of Fig. 1 differs from the adapter explained above

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■only because the hollow body 11 is designed on the drive side to accommodate a differently designed work spindle of the power tool. The threaded hole 13 is designed to accommodate a threaded pin of larger diameter, for example for an M 18x2.5 thread. In addition, the axial hole 12 contains bore sections with an enlarged diameter. Of these, sections 12' and 12" serve as guides for the work spindle, while section 12"' is an undercut.

In order to prevent dust or drilling dust that accrues when drilling exclusively with the drill bit 16 from settling to a disturbing extent in the axial bore 12 for receiving the centering bore 24 in the adapter, at least one transverse bore 25 is made in the wall of the hollow body 11, which extends into the axial bore 12. As a result of the centrifugal forces that act when the adapter rotates and the associated formation of negative pressure, the drilling dust is largely discharged to the outside through the transverse bores 25.

The transverse bores 25 can, as shown in particular in Figure 2, be designed as two radial bores lying opposite one another. It has proven advantageous to provide the transverse bores 25 in the shaft part of the hollow body 11 of the adapter following the threaded attachment 15 for receiving the diamond core bit 16.

The working spindle of the power tool is designated 27 in Figure 3.

This figure also shows the centering drill 24 inserted into the axial bore 12 with its grooves 28 opening out towards the end of the shaft, into which the rotary drive webs 14 of the adapter engage. This figure also shows the locking member 18 protruding into a groove 29 of the centering drill that is closed on both sides.

Claims (5)

. 1, L j c en ti ä ··' '··' ·· Patent-Verwaltungs-GmbH Theodor-Stern-Kai 1, 6000 Frankfurt 1 WN 89/16 Claims 1. Adapter that can be combined with the work spindle of a hand-held power tool for receiving tools equipped with a core bit, which has an axial bore that has a section with rotary drive webs that protrude inwards from its periphery, to which recesses made in the shaft of center drills (normal drills) are correspondingly assigned, and in the wall of which at least one continuous opening that opens into the axial bore is provided for receiving an element that effects the axial locking of a center drill and engages in a recess in this drill, characterized in that the locking element (18) is provided with a recess that is under the action of a return spring (20) acting in the axial direction, concentrically surrounds the adapter hollow body (11) and is provided with a chamber-like recess (23) for the radial deflection of the locking element (18). provided sliding sleeve (19) is assigned, the recess (23) of which can be brought into alignment with the locking element (18) by axial displacement of the sliding sleeve against the force of the return spring (20). 2. Adapter according to claim 1, characterized in that the locking element (18) is cylindrical in shape. 3. Adapter according to one of the preceding claims, characterized in that its hollow body (11) is provided with transverse bores (25) opening into the axial bore (12). 4. Adapter according to claim 3, characterized in that the transverse bores (25) are designed as radial bores. 5. Adapter according to claims 1 to 3, characterized in that the transverse bores (25) are provided in the shaft part of the hollow body (11) following the threaded attachment (1S) for receiving the drill bit (16).