Bulten-kanthal Aktiebolag

Bulten-kanthal Ab

Bulten-kanthal Ab Hallstahammar

Sixten H Lejdegard

Stig Lennart Bjorklind

Nils E Henriksson

A screw tightening apparatus comprising a motor-driven tool, a screw magazine for screws affixed to a strip-like carrier, and a screw advancing and tightening means for advancing the screws one at a time to a standby position in which a motor-driven bit may engage the screw for applying the same. A bell crank has a spring arm for advancing the screw strip and a drive arm driven by a projection on a plunger against the force of a feed spring to a cocked position, preparatory to advancement of the screw strip, the cocked position being maintained by a pivoted pawl which has a hook that locks the bell crank in such cocked position. A second projection on the plunger member engages the pawl to effect unlocking thereof near the end of a retracting stroke of the plunger member, whereby the feed spring drives the bell crank to advance the strip. A novel means for unlocking a spring-loaded axially slidable lock sleeve is provided. Further, a punch and die structure surround the screw head and cut a washer-like portion from the strip as the screw is applied.

Screw applicator

A screw package comprising a carrier strip through which the screws extend transversely with the essentially flat under surface of the screw heads resting against the upper surface of the strip. The strip has holes the diameter of which is closely related to the shank diameter of the screws. Around each hole there extend arcuate slots, between the ends of which comparatively weak webs have been left, or deep weakening lines, in such a manner that, as a screw is driven in, a washer consisting of the carrier strip material will be separated from the carrier strip to be clamped between the under surface of the screw head and the work piece wherein the screw is applied.

Screw package

A fastener package comprising a carrier tape having at equally spaced intervals throughgoing holes in each of which there is received from one side of the tape a screw with a head and a threaded shank, with the under side of the screw head resting against said one side of the tape. The holes are so designed and dimensioned in relation to the dimensions of the screw shanks that, on introduction of the screw shanks into the holes, the tape edges around the holes are deformed into lips which retainingly engage with the screw threads. Radial slots may facilitate the development of the retaining lips, and the slots may be long enough to permit deflection of the lips to let through the screw heads. Adjacent longitudinal slots may be so closely spaced that the tape is split up in two tape portions as the screws are driven home, through the tape.

Fastener package

A screw tightening apparatus comprising a motor-driven tool, a screw magazine for screws affixed to a strip-like carrier, and a screw advancing and tightening means for advancing the screws one at a time to a preparatory screw tightening position in which a bit portion of the motor-driven tool may engage with the screw for tightening thereof. The screw advancing and tightening means comprises two axially movable portions, one of which is secured to the tool and the other one of which carries the screw magazine and a spring biased screw advancing mechanism. A push and pull member on the stationary portion is adapted to cooperate with a dog means on the spring biased screw advancing mechanism for advancement of a new screw at the end of the retractive movement of the movable parts into a rest position, subsequent to a completed driving home of a screw. A latch holds the screw advancing mechanism temporarily in a retracted rest position during tightening of the screw and the first portion of the movement of the relatively movable portions into a retracted rest position and releases said screw advancing mechanism for advancement of a screw, at the final stage of said movement.

Power-driven screwdriver

An internal spline drive formation for screws is provided wherein the spline drive formation comprises a plurality of circumferentially alternating equiangularly spaced grooves and splines, said splines being defined in part by part-cylindrical surfaces and said grooves being defined in part by surfaces which, when viewed in plan, are arcuate to form a parabola-like line in that the radius of curvature is very small at the regions of intersection between the spline side surfaces and the groove bottom and increases gradually towards the center line of the groove bottoms. Also disclosed is a screw driving tool the bit end of which comprises an external spline drive formation having a surface which, when viewed in plan, comprises an outer cylinder having sunk therein a plurality of equiangularly spaced grooves, defined in part by re-entrant part-cylindrical surfaces, the regions of intersection between said grooves and said outer cylinder being sharp as contrasted to curved.

Internal spline drive configuration for threaded fasteners

The wrenching portion of a nut or a bolt head is provided with a configuration which, when viewed in plan, comprises an outer cylinder having a plurality of grooves defined in part by re-entrant concave surfaces and equiangularly spaced about its periphery, the regions of intersection of the grooves with the outer cylinder being planar. The grooves may be altogether part-cylindrical in cross section, or may they have a part-cylindrical bottom surface which merges with two planar inclined side surfaces. Also disclosed is a matrix or die for use in manufacture of nuts or bolts having a splined wrenching portion, said matrix or die having a die cavity adapted to form the regions of intersection of the grooves with the outer cylinder as planar surfaces.

Configuration for nuts and bolt heads

A screw driver bit for use with power screw drivers having at the mounting end thereof three equiangularly spaced axial recesses which form three equiangularly spaced drive surfaces for engagement by mating surfaces within a drive socket in the power screw driver.

Growing community of inventors

Ramnas, Sweden

Sixten H Lejdegard