Hilti Aktiengesellschaft

Rolf Bereiter

Gerhard Ehmig

Peter Goepfert

Franz Chromy

Edmund Narobe

Peter Von Flue

An explosive powder charge operated fastening element setting tool has a hydropneumatic damping unit (17) and includes a housing part (1) forming a piston guide (5, 6) for driving fastening elements and a handle part (15) displaceable against the force of the damping unit (17) in the setting direction relative to the housing part (1). The handle part (15) supports a cylinder (18) containing a liquid medium (21) under gas pressure. The housing part (1) cooperates with a piston (23) displaceable in the cylinder (18) against the flow resistance of the liquid medium (21). The damping unit (17) has no moving valve parts. At least one through aperture (24) is provided for the liquid medium (21) flow between a front and a rear cylinder space when the piston (23) is displaced. The aperture (24) has a least cross-section (M) so that the liquid medium flowing into the front cylinder space as a fastening element is driven has an effective flow cross-section corresponding to the least cross-section of the aperture (21), while after the fastening element has been driven the effective flow cross-section of the aperture from the front cylinder space into the rear cylinder space is smaller than the least cross-section of the aperture.

Explosive powder charge operated fastening element setting tool

An explosive powder charge operated fastening element setting tool includes an interceptor (14) for intercepting or cushioning a driving piston (8) in the event excess energy is supplied to the piston in driving a fastening element into a receiving material. The driving piston (8) has a shoulder (12a) displaceable when excess energy is present into the axially extending region of a deformable stopper (27) in contact with a bolt guide (4). If the interceptor (14) for the driving piston (8) does not afford an adequate braking, the shoulder (12a) runs up against the stopper (27) and the stopper is deformed and tightly clamps or jams the driving piston (8) so that it can not be freely displaced. When such jamming action takes place, the tool operator is signaled that a buffer (23) between the interceptor and the bolt guide and possibly the stopper (27) need to be replaced.

A loading strip (1) for supplying individual explosive powder charges in a setting tool is formed of an elongated belt-shaped member (2). The member has openings (2a) therethrough with a hollow receptacle (3) projecting outwardly at each opening from one surface of the member (2). The interior of the hollow receptacle (3) in combination with the corresponding opening (2a) form a space for holding an explosive powder charge. Annular gap (2b) encircles each opening (2a) and extends inwardly from the opposite side of the member from the receptacles. A bulge-like projection extends into the space formed by the receptacle and the member. The projection has a hollow recess (2c) located eccentrically relative to the opening and the hollow space and faces the opposite side of the member (2). An ignition medium (6) is placed in the hollow recess (2c). A base plate (7) forms a closure for the explosive powder charge space and the ignition medium hollow recess.

Belt-shaped loading strip

An anchor bolt assembly includes an axially elongated bolt and an axially elongated expanding sleeve laterally encircling the bolt. The sleeve is axially slotted from its leading end. The bolt includes an axially elongated cylindrically shaped shank with a frusto-conical section at its leading end and means for attaching a load to the bolt at its trailing end. A stop extends axially outwardly from the leading end of the frusto-conical section. In the axially extending region of the slots, the outer surface of the sleeve has an axially extending reduced diameter section.

Anchor bolt assembly including a bolt and an expanding sleeve

In the separation of solids out of a flushing liquid such as used in flushing out boreholes and the like drilled or cut in rock, concrete, masonry and similar materials, a flocculant is added to the flushing liquid before it enters a settling tank so that the removal of the solids is accelerated. As a result, a supply of flushing liquid, free from solids, is always available from the settling tank. The flushing liquid flow is directed through the feed line into the settling tank. Before the liquid enters the settling tank it is passed in contact with a flocculant so that the liquid picks up a dosed quantity of the flocculant. To assure the optimum effect, after contacting the flocculant, the liquid is mixed and then passed into the settling tank.

Method of and apparatus for separating solids from a flushing liquid

A self-drilling anchor dowel has a drill head at one end of the axially elongated dowel and a truncated cone-shaped projection at the other end. The projection fits into an adapter or holder on a drilling device. Immediately following the drill head is a frusto-conical clamping part which tapers inwardly in the direction away from the head. A collar extends laterally outwardly from the smaller diameter end of the clamping part. The outside diameter of the collar is the same as the outside diameter of the drill head. When the dowel is drilled into a receiving material, such as concrete or rock, and the collar enters the borehole formed by the dowel, the collar prevents the borings formed in the drilling operation from being discharged out of the borehole. As the collar continues into the borehole, it compacts the borings which anchor the dowel in the borehole.

Self-drilling anchor dowel

A hammer drill is arranged to rotate and also apply percussive force to a tool receptacle. The percussive force is transmitted from a shaft to a drive piston which, in turn, reciprocates a percussion piston which drives the tool receptacle. The hammer drill includes a housing and a bearing rotatably mounted in the housing. The shaft is rotatably mounted in the bearing and its axis extends perpendicularly of the axis of rotation of the bearing. The bearing supports a contact rim which is in meshed engagement with the shaft. The contact rim is displaceably into frictional contact with a brake member for holding the contact rim against rotation while the bearing rotates carrying with it the shaft. Due to its meshed engagement with the contact rim, the shaft rotates about its own axis causing the drive piston to reciprocate.

Growing community of inventors

Grabs, Switzerland

Rolf Bereiter