Abstract: An arrangement for transmitting a torque from a power tool to a working tool and including a shank forming part of the working tool and having following one another, in the operational direction of the working tool, first, second, third, and fourth regions (B1, B2, B3, B4), at least two drive grooves (3) extending parallel to a working tool axis over all of the shank regions (B1, B2, B3, B4), and at least one additional drive groove (4) extending in third and fourth regions (B3, B4) of the shank (2), with the arrangement further including a chuck (10) having an opening (13) for receiving the shank (2), at least one locking element (21) projecting into the receiving groove (13) for engagement into the circumferential groove (5) of the shank (2), at least two drive dogs (16) and an additional drive dog projecting into the receiving groove (13) for engagement in the first drive grooves (3) and the at least one additional drive groove (4).

Abstract: An arrangement for transmitting a torque from a power tool to a working tool and including a shank forming part of the working tool and having following one another, in the operational direction of the working tool, first, second, third, and fourth regions (B1, B2, B3, B4), at least two drive grooves (3) extending parallel to a working tool axis over all of the shank regions (B1, B2, B3, B4), and at least one additional drive groove (4) extending in third and fourth regions (B3, B4) of the shank (2), with the arrangement further including a chuck (10) having an opening (13) for receiving the shank (2), at least one locking element (21) projecting into the receiving groove (13) for engagement into the circumferential groove (5) of the shank (2), at least two drive dogs (16) and an additional drive dog projecting into the receiving groove (13) for engagement in the first drive grooves (3) and the at least one additional drive groove (4).

Abstract: The present invention relates to a suction and discharge apparatus for a drilling fluid, which is used in material removing treatment of hard constructional components formed of concrete, stone, break work, and the like, and including at least two air- and liquid-tight reservoirs (1,2), with the first reservoir being connected with a vacuum-producing device (6) and a suction conduit (3), with the second reservoir (2) being connected with an overpressure-producing device (4) and a discharge conduit (4), and with both reservoirs (1, 2) being connected by a conduit (5).

Abstract: A hand-held tool for driving a cutting or grinding disk includes a housing and a protection hood with a sleeve-shaped extension detachable connected to the housing. A receptacle is mounted on the housing for releaseably holding the sleeve-shaped extension. The receptacle is formed as a slotted sleeve so that it has a variable diameter. The diameter is changed by moving circumferential ends of the sleeve toward or away from one another. The displacement of the sleeve ends can be effected by a lever pivotly mounted on the ends.

Abstract: A drill stand includes a base plate, an elongated guide column extending outwardly from the base plate and a drilling device movably supported on the column. The guide column is formed of two laterally spaced elongated support members each having the same cross-section transversely of the elongated direction. A drilling device is positioned between the two support members. A rack is secured to the guide column and a feed mechanism for moving the drilling device includes a pinion in meshed engagement with the rack. Guide members on the support members fit into correspondingly shaped guide grooves on the drilling device.

Abstract: In a device for drilling rock, concrete, reinforced concrete and similar materials, a spindle is rotatably mounted in a housing and a drilling tool is replaceably mounted on the spindle so that the spindle and drilling tool rotate together. A gear wheel is fitted on the drilling tool. A motor is located on the housing laterally spaced from the axis of rotation of the spindle. The motor includes a drive pinion which drives an intermediate gear. The intermediate gear meshes with the gear wheel and drives the drilling tool and spindle. The spacing between the axis of the intermediate gear and the spindle is adjustable.

Abstract: In a stand for supporting a drilling tool, a guide block is movably supported on a guide column. The drilling tool is attached to the guide block. Rollers are mounted in the guide block and contact the guide column for effecting rolling movement of the block along the column. Elastic members associated with the rollers assure contact between the rollers and the column.