Abstract: A suction and blowing device exhibits three air conduits connected to a source of pressurized air and partially terminating in a common transport conduit and has a selectable control body located between the air conduit entrance openings and the pressurized air source for regulating the entrance of the pressurized air into the air conduits. The device allows for the selective direction of pressurized air to one or more of the three air conduits to perform completely different functions such as: suction with an injector nozzle, vacuum cleaning using an injector nozzle and an additional cleaning pressure jet, blowing using a nozzle with large dynamic pressure and air velocity, and blowing using an injector nozzle and high air through-put.

Abstract: The invention relates to a two-handle arrangement for a handheld portable tool having a drive motor and equipped with forward and rearward handles for two-handed operation. Each of these handles includes respective actuating elements which can be actuated only in a specific sequence. First, force must be applied to the actuating element on the forward handle and only when a corresponding actuation of the throttle lever takes place is there an increase in the speed of the drive motor. The invention is especially suited for handheld portable tools equipped with an internal combustion engine such as motor-driven chain saws, hedge trimmers and the like.

Abstract: The invention relates to a two-handle arrangement for a handheld portable tool having a drive motor and equipped with forward and rearward handles for two-handled operation. Each of these handles includes respective actuating elements which can be actuated only in a specific sequence. First, force must be applied to the actuating element on the forward handle and only when a corresponding actuation of the throttle lever takes place is there an increase in the speed of the drive motor. The invention is especially suited for handheld portable tools equipped with an internal combustion engine such as motor-driven chain saws, hedge trimmers and the like.

Abstract: The invention is directed to a rearward handle arrangement for a handheld portable tool defining a horizontal axis and having a motor housing and a forward handle fixedly attached to the housing so as to permit two-handed operation of the tool by an operator. The rearward handle arrangement includes: a carrier part for attaching the rearward handle arrangement to the housing of the tool; a rearward handle; and, a bearing journal for rotatably journalling the rearward handle in the carrier part so as to permit the rearward handle to rotate about the horizontal axis relative to the carrier part and the forward handle. The carrier part and the reaward handle conjointly define an interface and an unlatchable detent is disposed at this interface for self-latching the rearward handle on the carrier part at any one of a plurality of predetermined angular positions about the horizontal axis. These angular positions correspond to respective work positions in which the tool can be held by the operator.

Abstract: The invention is directed to an arrangement for actuating a braking device for bringing a motor-driven work tool of a work apparatus to standstill. The braking device is actuated by a brake lever and the brake lever is connected to a pivotably journalled throttle lever via a first actuator. The throttle lever controls the carburetor of the engine driving the work apparatus via a second actuator. In order to bring the work tool rapidly to standstill in idle, the second actuator is attached to a drag lever which is pivotable relative to the throttle lever. After passing through an idle movement path, the throtle lever takes the drag lever along via a follower in a pivot direction.

Abstract: The invention is directed to a starter arrangement for an internal combustion engine wherein a manual starter device is combined with an electrical starter. Handheld portable tools such as motor-driven chain saws, brushcutters and the like are driven by two-stroke engines which can be started with a suitable manual starter device such as a pull-rope starter. Pull-rope starters require a forceful yank on the pull rope which is difficult for persons having inadequate physical strength. For this reason, electrical starters are provided to facilitate starting such handheld portable tools. The invention combines an electric starter and a manual starter device wherein the overrun clutch of the manual starter device includes a latching device and a drive member and is combined with a further latching device which coacts with a drive member driven by the electric starter.

Abstract: The invention is directed to a portable handheld tool such as a brushcutter which includes a work tool assembly and a drive motor connected by a drive shaft. The drive shaft is surrounded by a protective tube and is centrally held therein by means of a bearing sleeve unit. The bearing sleeve unit braces itself against the inner peripheral wall surface of the protective tube via outwardly extending supporting ribs. The mounting of the bearing sleeve unit within the protective tube must be adapted precisely with respect to tolerances in order to prevent damaging deformations of the bearing sleeve unit and to prevent the bearing sleeve unit from vibrating within the protective tube. At least one of the supporting ribs is configured so as to be resilient in the radial direction so that it effects a tolerance compensation as well as attenuates vibration.

Abstract: A tool chuck for a hammer drill has an inner sleeve and an axially slidable outer sleeve concentrically surrounding the inner sleeve. The inner sleeve has an open leading end adapted to receive a shank of the tool. The shank is clamped in the inner sleeve with a snap action in response to insertion of the shank through the open end. Torque and/or axial impact are selectively imparted to the tool chuck from a drive of the hammer drill. The tool shank is formed with a radially outwardly opening recess closed at both axial ends and shaped to receive a tool-holding element and with at least one axially extending groove. A formation is formed in the inner sleeve which is engageable with the axially extending groove for torque transmission. A ring is positioned between the outer sleeve and the inner sleeve. The ring is movably biased by a spring in axial direction and is provided with a projection engageable with the tool-holding element when the latter is moved outwardly of the recess.

Abstract: A drilling tool has a drilling shaft member, a crown drilling member with an annular wall provided with a plurality of cutting edges and detachably mounted on the shaft member, a center drilling member detachably mounted on the shaft member inside the crown drilling member and having a further cutting edge, and elements for limiting a drilling depth of the tool when the center drilling member is mounted on the shaft member. Thereby, the operator of the drilling tool, after drilling a guiding groove in a rock, is forced to remove the center drilling member from the drilling tool and drill further without the center drilling member, which increases the drilling efficiency.

Abstract: An arrangement for producing grooves in walls, ceilings and the like with the use of a hand-held processing machine, has a rotatable material-removing tool driven in rotation by the machine, and a housing surrounding the tool. The housing has a guiding piece through which the tool extends. The guiding piece has a guiding surface which is adapted to lie on the surface of the wall, ceiling and the like, and is inclined at an acute angle relative to the axis of the tool. The guiding piece is detachably mounted on the processing machine.