A thread rolling screw molten through friction which is involved in metal plate installation field is publicized in the invention, and it is used to solve the problem that the method for breaking through the tradition is not formed for current connecting thread of metal plate structure to realize the simple and rapid efficiency improvement. The top of locating tip of the stated cone is connected with the expanding cone in a fixed way. The top of the stated expanding cone is connected with the pored shaping section in a fixed way. The top of the stated pored shaping section is connected with the transition section in a fixed way. The top of the stated transition section is connected with the self-tapping thread section in a fixed way. The external surface of the stated self-tapping thread section is set with tapered thread. The top of the stated self-tapping thread section is connected with the cylindrical locking thread section in a fixed way. The external surface of the stated cylindrical locking thread section is set with external thread. The top of the stated cylindrical locking thread section is connected with the transition fillet in a fixed way. The top of the stated transition fillet is connected with the concave storage ring in a fixed way. The top of the stated concave storage ring is connected with the flange in a fixed way.

A joining method is a method of joining a plate set composed by a plurality of stacked plate members including a first plate member and a second plate member by using a tapping screw. When the tapping screw is advanced into the plate set while the tapping screw is rotated in a state of applying a pressure onto the plate set so as to form through-holes in the first plate member and the second plate member, a first pressure applied onto the tapping screw is reduced down to a second pressure at the time when the tapping screw penetrates the first plate member.

In order to prevent wood fringes at the edge of a hole from a countersunk screw (1), the screw-head (2) is provided with a tapering underside and inclined milling-ribs (8) on the tapering underside. Each milling-rib (8) has a planar front-side (15) delimited by smoothly curved convex milling-edge (17) for milling the material during countersinking of the screw-head (2).

A panel fastener is provided that has a head having a first surface and a second surface opposite the first surface; an engagement feature on the first surface of the head, the engagement feature being configured to be engaged by a driving tool; a shank extending from the second surface of the head; a threaded portion extending from the shank, the threaded portion having first and second helical threads arranged in an intertwined manner; the first thread extending farther radially from the central axis than does the second thread; and the shank being located between the head and the threaded portion.

A vehicle assembly includes a first component having a stand-off that provides a cavity. The stand-off protrudes from an insertion side of the first component. The stand-off includes at least one side wall that extends from a floor of the cavity to at least one outer surface of the stand-off. The assembly further includes a second component that contacts the first component at an interface. The cavity is configured to receive a mechanical fastener that joins the first component to the second component. A distance between the floor of the cavity and the interface is greater in some areas than in other areas such that a cross-sectional thickness at a bottom of the cavity is varied.

Various embodiments provide a fastener including a head, a shank connected to the head and having a tip, one or more helical thread formations extending outwardly from the shank, and wherein a bottom portion of the head includes a plurality of ribs that extend towards the tip of the shank and that are shaped to abruptly frictionally engage a surface of a first object being attached to a second object to create an immediate frictional torsional resistance of a desired force level to the tightening of the fastener. This frictional resistance is provided back to the tightening tool to inform the operator of the tightening tool that the head of the fastener has sufficiently engaged the first object and that further tightening or clockwise rotation of the fastener is unnecessary.

A method of installing and sealing a friction fastener to at least an upper substrate and a lower substrate includes providing an expandable sealant to an underhead volume of the friction fastener, installing the friction fastener through the upper substrate and into the lower substrate using a joining device, and applying heat in-situ to the expandable sealant such that the friction fastener is sealed to at least the upper substrate. The heat in-situ is applied to the expandable sealant via installing the friction fastener and/or with an external heating source disposed downstream from the joining device.

The invention relates to a joining element comprising a shaft to be placed into a component; a head provided at a first end of the shaft; and a punching element attached in a losable manner to a second end of the shaft remote from the head.

Various embodiments provide a fastener including a head, a shank connected to the head and having a tip, one or more helical thread formations extending outwardly from the shank, and wherein a bottom portion of the head includes a plurality of ribs that extend towards the tip of the shank and that are shaped to abruptly frictionally engage a surface of a first object being attached to a second object to create an immediate frictional torsional resistance of a desired force level to the tightening of the fastener. This frictional resistance is provided back to the tightening tool to inform the operator of the tightening tool that the head of the fastener has sufficiently engaged the first object and that further tightening or clockwise rotation of the fastener is unnecessary.

The present invention provides a fast chip removal reaming screw, including a screw head, a rod body extending from the screw head and a first thread arranged on the rod body. The rod body includes a rod body portion connected to the screw head, an reaming portion, and a pointed cone portion. The reaming portion includes first reaming blocks, second reaming blocks and third reaming blocks which are disposed in a helically staggered manner, and chip removal paths formed between the first reaming blocks, the second reaming blocks and the third reaming blocks. A first width of the chip removal path located between the first reaming blocks and a second width of the chip removal path located between the second reaming blocks are different, so that wood chips can be fast removed to reduce a stress between the screw and a wood workpiece.