Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
  • F16B—DEVICES FOR FASTENING OR SECURING CONSTRUCTIONAL ELEMENTS OR MACHINE PARTS TOGETHER, e.g. NAILS, BOLTS, CIRCLIPS, CLAMPS, CLIPS OR WEDGES; JOINTS OR JOINTING
  • F16B25/00—Screws that cut thread in the body into which they are screwed, e.g. wood screws
  • F16B25/10—Screws performing an additional function to thread-forming, e.g. drill screws or self-piercing screws
  • F16B25/106—Screws performing an additional function to thread-forming, e.g. drill screws or self-piercing screws by means of a self-piercing screw-point, i.e. without removing material
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
  • F16B—DEVICES FOR FASTENING OR SECURING CONSTRUCTIONAL ELEMENTS OR MACHINE PARTS TOGETHER, e.g. NAILS, BOLTS, CIRCLIPS, CLAMPS, CLIPS OR WEDGES; JOINTS OR JOINTING
  • F16B25/00—Screws that cut thread in the body into which they are screwed, e.g. wood screws
  • F16B25/10—Screws performing an additional function to thread-forming, e.g. drill screws or self-piercing screws
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
  • F16B—DEVICES FOR FASTENING OR SECURING CONSTRUCTIONAL ELEMENTS OR MACHINE PARTS TOGETHER, e.g. NAILS, BOLTS, CIRCLIPS, CLAMPS, CLIPS OR WEDGES; JOINTS OR JOINTING
  • F16B23/00—Specially shaped nuts or heads of bolts or screws for rotations by a tool
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
  • F16B—DEVICES FOR FASTENING OR SECURING CONSTRUCTIONAL ELEMENTS OR MACHINE PARTS TOGETHER, e.g. NAILS, BOLTS, CIRCLIPS, CLAMPS, CLIPS OR WEDGES; JOINTS OR JOINTING
  • F16B25/00—Screws that cut thread in the body into which they are screwed, e.g. wood screws
  • F16B25/001—Screws that cut thread in the body into which they are screwed, e.g. wood screws characterised by the material of the body into which the screw is screwed
  • F16B25/0021—Screws that cut thread in the body into which they are screwed, e.g. wood screws characterised by the material of the body into which the screw is screwed the material being metal, e.g. sheet-metal or aluminium

Definitions

• the invention relates to a screwed into a piece of sheet metal hole and wind-forming screw with a tool holder having head, a threaded shaft, a slightly conically tapered hole forming part and a punch.
• Such a screw is known from European Patent 0 464 071 Bl.
• a perforated friction member is used, which is designed as a tapered piece, which terminates in a rounded tip. This tip is placed on a piece of sheet metal, so that upon rotation of the screw, the material of the sheet metal piece is soft and the cone piece can penetrate the piece of sheet metal, whereby a hole in the piece of sheet metal is formed.
• the conical piece is followed by a substantially slimmer conical hole forming part, which penetrates into the hole formed by the perforated friction part and then expands it to its largest diameter under frictional heat by the rotation of the screw.
• a passage is formed from the material of the sheet metal part, which extends on both sides of the sheet metal part, in particular also on that side from which the screw is placed on the sheet metal part. The passage on this page is undesirable in many cases.
• the invention has for its object to provide a hole- and thread-forming screw with which when creating a hole in a piece of sheet metal for later screwing a thread a passage essentially only on that side is turned away from the touchdown of the screw on the piece of sheet metal ,
• the screw should be designed so that the heat necessary for the formation of the hole in a particularly short time after placement of the screw on the piece of sheet metal can be generated.
• the perforated friction member is formed as a radial shoulder, which surrounds a piece of gel piece which can be placed on the sheet piece coaxially, has a relative to the cone piece substantially larger diameter and passes over a rounded edge of the ring in the hole molding.
• the screw according to the invention exerts with its designed as a radial shoulder hole friction part when pressing the screw on the piece of sheet pressure, which gives the softened in the rotation of the screw due to frictional heat material of the piece of sheet tendency, in front of the radial shoulder in the direction of the pressure exerted on the piece of sheet metal pressure to avoid and thus form a passage with a clean edge, which does not bother normal on the side facing away from the screw of the piece of sheet metal, but in any case does not have the tendency to extend to the Aufsetzseite of the piece of sheet out.
• the radial shoulder This can be designed so that it extends substantially at an angle of 90 ° to the screw axis. On the other hand, it is also possible to form the radial shoulder as a blunt cone. In this design, a particularly favorable effect on the flow behavior of the material of the sheet metal piece results.
• the radial shoulder concave arched run.
• the individual design of the radial shoulder then depends essentially on the material of the sheet metal piece. Furthermore, the design of the radial shoulder has a favorable influence on the pressure to be applied and the rotational speed.
• the conical piece can be left to run off in a blunt rounded end piece, as disclosed, for example, in EP 0 464 071 B1. You can also run the cone piece in a tip, which then, however, a relatively large pressure on the tip must be exercised to form a hole.
• Another particularly advantageous design of the cone piece is to give it a coaxial depression which is surrounded by a blunt edge whose outer diameter (d) is 0.35 to 0.7 times smaller than the largest diameter (D). of the hole molding.
• Figure 1 shows the screw in perspective view
• Figure 2 is a section along the line H-II of Figure 1 with radially extending radial shoulder;
• FIG. 3 shows a similar section with a conically extending radial shoulder
• Figure 4 shows a similar section with concave radial shoulder
• FIG. 5 shows a similar section with rounded curvature projecting with respect to the radial shoulder;
• FIG. 6 shows the perforated friction part with a tapered piece extending in a point;
• Figure 7 is a perforated friction member with a cone piece with coaxial recess
• Figure 8 is a section along the line VIII-VIII of Figure 7;
• the hole and thread forming screw 1 according to the invention is shown in a perspective view.
• the screw has the screw head 2, the threaded shaft 3 and the hole-forming part 4, to which the perforated friction part 5 is preset.
• the punch friction part consists of the radial shoulder 6 and the cone piece 7.
• the cone piece 7 is placed on the piece of sheet metal and set in rotation. Due to the resulting frictional heat, the cone piece 7 penetrates into the piece of sheet metal until the radial shoulder 6 also impinges on the piece of sheet metal and ensures with its relatively large diameter for rapid heating of the relevant area of the piece of sheet metal.
• the radial shoulder 6 presses the softened material from the piece of sheet metal in front of it, ie in the direction of the screw 1 side facing away from the piece of sheet metal, so that a molded from the softened material of the piece of sheet passage substantially on this side facing away from the screw of the piece of sheet metal forms (see Figures 9a to c).
• the radial shoulder thus has a double function, since on the one hand provides a favorable way for rapid heating of the material of the piece of sheet metal and on the other hand, the heated and thus softened material from the piece of sheet in front of him pushes on the side facing away from the screw of the piece of sheet metal.
• the cone piece 7 used in the screw 1 according to Figure 1 has a rounded end 7a, which ensures that when placed on a piece of sheet metal at a correspondingly high pressure on the piece of sheet quickly results in a surface contact and thus corresponding friction heat. This is particularly advantageous when it comes to screwing the screw 1 in a sheet metal piece consisting of relatively hard material, that is, for example, a sheet metal piece made of steel.
• This design has the consequence that initially only the central cone piece 10 penetrates into the material of the sheet metal piece, until then the radial shoulder 9 touches down with its inner region and presses with increasing diameter on the edge of the resulting hole, resulting in a transition to a greater compressive stress yields and finally on reaching the outer edge of the radial shoulder 9, the greatest pressure is exerted on the piece of sheet metal.
• Figure 4 shows a section similar to that of Figure 2.
• the radial shoulder 11 of the perforated friction member 12 extends concavely, whereby the transition of the friction load from the region of the central cone piece 13 to the radial shoulder 11 is further equalized.
• FIG. 1 A special design of the perforated friction part is shown in FIG.
• the concavely curved radial shoulder 11 at its outer edge goes into a jumping ring edge 14 via, which traps the material which has become movable when softening the material of the piece of sheet material, so to speak, and holds it together, whereby this is almost entirely available to a pull which forms on the side of the piece of sheet facing away from the screw.
• FIG. 15 Another variant of the cone piece is shown in FIG.
• the cone piece 15 shown here terminates in a point 16 which, especially when the screw is used, is supported on relatively soft material, e.g. Aluminum, is advantageous.
• FIG. 7 A particular design of the cone piece is shown in Figures 7 and 8, wherein Figure 8 shows a section along the line VIII-VIII of Figure 7.
• the cone piece 17 at its end a coaxial recess 18 which is surrounded by a blunt edge 19.
• This blunt edge 19 has an outside diameter of 2 mm with respect to a maximum diameter of the cone piece 17 of 5 mm. Due to the blunt edge 19 is obtained when placing the cone piece 17 on a piece of sheet metal immediately a relatively large area and a correspondingly large heating during rotation of the screw, which greatly facilitates their penetration into the piece of sheet metal.
• the recess 18 is formed by a short bore, which is about 2 mm deep.
• FIGS. 9a, b and c show screwing a screw into a piece of sheet metal 20 and forming a passage 22, the design of a screw shown in FIG. 1 being used as a basis.
• the cone piece 7 rounded off at its end 21 has penetrated into the material of the piece of sheet metal 20 and has softened accordingly.
• the cone piece 7 has completely penetrated the sheet metal piece 20.
• the threaded shaft 3 has penetrated the sheet metal piece 20 and thereby generated the passage 22, which is here exclusively on the side that the touchdown the screw is turned away on the sheet metal piece 20.

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• Engineering & Computer Science (AREA)
• General Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Connection Of Plates (AREA)
• Forging (AREA)
• Milling Processes (AREA)

Applications Claiming Priority (2)

Publications (1)

Family

ID=38565608

Family Applications (1)

Country Status (10)

Families Citing this family (8)

Family Cites Families (16)

• 2006
  • 2006-07-26 DE DE102006034585A patent/DE102006034585A1/de not_active Withdrawn
• 2007
  • 2007-07-23 MX MX2009000732A patent/MX2009000732A/es not_active Application Discontinuation
  • 2007-07-23 BR BRPI0714664-7A patent/BRPI0714664A2/pt not_active Application Discontinuation
  • 2007-07-23 CN CNA200780026710XA patent/CN101517249A/zh active Pending
  • 2007-07-23 AU AU2007278469A patent/AU2007278469A1/en not_active Abandoned
  • 2007-07-23 JP JP2009521160A patent/JP2009544907A/ja not_active Withdrawn
  • 2007-07-23 EP EP07765246A patent/EP2044340A1/de not_active Withdrawn
  • 2007-07-23 KR KR1020097000715A patent/KR20090034873A/ko not_active Application Discontinuation
  • 2007-07-23 WO PCT/EP2007/006536 patent/WO2008012052A1/de active Application Filing
  • 2007-07-23 US US12/307,717 patent/US20090311075A1/en not_active Abandoned

Non-Patent Citations (1)

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