| 摘要 |
Tool holders (6) which are arranged on the free end of the rotatable drive spindle (4) of a hand-operated device, for example a ratchet screwdriver, have a tool-receiving sleeve (7) which is made of a non-magnetisable material, has a polygonal insertion opening (9) for the screwdriver bit (10) and contains a permanent magnet behind that. In order to increase the holding force of this permanent magnet without increasing the constructional dimensions of the tool holder (6), the permanent magnet is designed as a pot-shaped magnet (11, 12), the annular wall part (11) of which extends the polygonal insertion opening (9) to the rear, and against the base (12) of which the inserted screwdriver bit (10) bears. The pot-shaped magnet advantageously consists of a permanently magnetic ring (11) forming its wall part and a disc (12) of magnetisable material forming its base and bearing against the rear side of the ring (11), it being possible for a circular-cylindrical permanent magnet (13) to also be arranged behind the base disc (12), which circular-cylindrical permanent magnet (13) bears with the same magnetic polarity as the magnetic ring (11) against the base disc (12). <IMAGE>
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