DE8423757U1 - DRILL FOR MAKING CYLINDRICAL EXCLUSIONS IN PLASTIC PIECES - Google Patents

Description

■ /

BAYER AKTIENGESELLSCHAFT 5090 Leverkusen, Bayerwerk

Group administration RP

Patent department KR / Ke-c

¹ ' ¹ Aug 19, 1984

Drill for producing cylindrical recesses in workpieces made of plastic

The innovation relates to a drill for producing cylindrical recesses in workpieces made of plastic, in particular Hollow channel plates, consisting of cutting edges and a central guide.

Holes in hollow channel plates can hardly be carried out cleanly with conventional solid core drills, because on the one hand Bridges lying asymmetrically to the drilling axis lead to the drill running and on the other hand to the distances an undefined falling through of the drill cannot be avoided between the outer plates.

The task of the innovation is to find a drill that avoids the disadvantages described above.

The object is achieved according to the invention in that the cutting edges on the end face of a rotatable tube at » are ordered and that as a guide a sliding body movable along the inner wall of the pipe by a spring is pressed into an end position in which at least one surface of the sliding body for placing on the workpiece

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with a center point that protrudes further outwards - viewed in the direction of drilling - lies in front of the cutting edges.

Due to the circularly arranged cutting edges, the webs are only cut in a small area, so that the resulting low lateral forces without difficulty on the guidance of the sliding body by the center point penetrating the plate when the drill is placed.

A falling through of the drill is also avoided as soon as a ridge is underneath, which is because of the usual Bar spacing is almost always the case with the building boards used in practice; or the drill will so safely guided by the smooth wall of the tube in the first drilled recess that also in the plate lying underneath it creates a flush hole when drilling.

In a special embodiment, the cutting edges consist of saw teeth.

The saw teeth are easy to machine or to sharpen later. By lightly locking (reciprocal Deflection), jamming can be avoided. Tungsten carbide plates can also be soldered on as cutting edges, thereby extending the life of the drill is increased.

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\ Ir; Another embodiment consists of the sliding

\ body from an element that can be axially guided in the pipe, at

I that in an area, which in the end position, the saw

i teeth opposite, the maximum dimensions

I 5 are smaller than the clear distances between the saw teeth j - measured through the pipe axis.

'' The sliding body, which is cylindrical for guidance in the pipe,

i can have polygonal or protruding ribs,

i is in the part opposite the in the lowest point

j 10 teeth is formed thinner to make a contact with] geschränkten sawteeth during preparation of the drill to comparable

I avoid.

j In a further embodiment, the element has

! a shaft with a projection in a sliding track

j 15 parallel to the pipe axis, in which there is also one on the pipe I attached stop lies.

A spring, which is supported on the tube, pushes the element in the direction of the teeth until the one with the element Is driven via the stem connected projection against the stop 20 of the tube. So it is achieved that on the one hand the element does not fall out of the drill and on the other hand due to its precisely adjustable end position after penetration of the center point touches the workpiece over the entire surface before the cutting edges grip.

In one embodiment, a bass stop is outside of the pipe provided.

Le A 23 297

With a ring as a depth stop, which is fixed to the pipe with a screw, for example a certain drilling depth can be set in advance.

An example is shown in the drawing and is explained below.

In the Fig. A drill 1 is shown, which consists of a tube 2, which on one end face with formed as saw teeth cutting 3 is provided and which on the opposite side - as a clamping part 4 in the drill (not shown) is tapered. In the tube 1 is a sliding body 5 arranged, which consists of a cylindrical element 6, which on one side after is offset on the inside, the outer surface 7 having a projecting centering point lying in the tube axis 8 possesses, and a shaft 10 with a collar obtained by twisting as a projection 11 of the one as a stop 12 trained screw is applied. The spring in the tube is supported against the bearing 14 and the cylindrical Element 6. On the outside of the tube, a ring is seated as a depth stop 15, which is fastened with a screw is fixed on the pipe 1.

The rotating drill 1 according to FIG. 1 is placed on the twin-wall sheet placed, the centering point penetrates the upper plate until the surface 7 of the Slider 5 rests firmly. When the drill 1 is lowered further, the saw teeth come into engagement and

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I I I I I UIM ~,

- 5 -; i

cut the recess. The drilling depth can be limited by the depth stop 15, which is rests against the upper plate at the set depth. Through the sliding body guided inside the tube the drilling direction is guided exactly so that a clean cut is produced.

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Claims (5)

Protection claims: 1. Drill for making cylindrical recesses in workpieces made of plastic, in particular twin-wall sheets, consisting of cutting edges and a central guide, characterized in that the cutting edges (3) on the end face of a rotatable Tube (2) arranged and as a guide a sliding body (5) which can be moved along the tube wall is pressed by a spring (13) into an end position in which a surface (7) of the sliding body (5) for Placed on the workpiece with a center point (9) protruding further outwards from it - viewed in the drilling direction - lies in front of the cutting edges (3). 2. Drill naoh claim 1, characterized in that the cutting edges (3) consist of saw teeth. 3. Drill according to claims 1 and 2, characterized in that that the sliding body (5) consists of an element (6) which can be guided axially in the tube (2), at the maximum dimensions in an area that lies opposite the saw teeth (3) in the end position smaller than the clear distance ler saw teeth (3) - measured through the pipe axis (8). 4. Drill according to claims 1 to 3, characterized in that the element (6) has a shank (10) Projection (11) parallel in a sliding path Le A 23 297 to the pipe axis (8), in which there is also a stop (12) attached to the pipe (1). 5. Drill according to claims 1 to 4, characterized in that a depth stop (15) outside of the tube (2) is provided. Le A 23 297