Process for anchoring connecting elements in a material with pores or cavities and connecting elements therefor

• US 6,913,666 B1
• Filed: 03/19/1998
• Issued: 07/05/2005
• Est. Priority Date: 03/21/1997
• Status: Expired due to Term

• Current Assignee: Woodwelding AG
• Original Assignee: Woodwelding AG
• Inventors: Aeschlimann, Marcel, Koester, Heinz, Torriani, Laurent, Mock, Elmar
• Primary Examiner(s): CORCORAN, GLADYS JOSEFINA-PIA
• Application Number:
  US09/381,526
• Time in Patent Office: 2,665 Days
• Field of Search: 156/92, 156/303.1, 156/306.6, 156/309.6, 156/73.2, 156/221, 156/91, 156/917, 156/73.1, 156/73.5, 156/73.6, 156/293, 428/223, 411/500, 411/501, 411/506, 411/507, 411/900, 411/901, 411/908, 144/355, 527/01, 403/266, 403/296, 247/06, 247/114, 247/031, 24D/IG.11
• US Class Current: 156/73.1
• CPC Class Codes: B29C 65/06 using friction, e.g. spin welding non-plastics elements to plastic elements B29C65/645
• CPC Class Codes: B29C 65/08 using ultrasonic vibrations non-plastics element to plastics elements B29C65/645
• CPC Class Codes: B29C 65/36 heated by induction
• CPC Class Codes: B29C 65/3612 comprising fillers
• CPC Class Codes: B29C 65/368 with a polymer coating
• CPC Class Codes: B29C 65/3696 with a coating
• CPC Class Codes: B29C 65/56 using mechanical means or mechanical connections, e.g. form-fits
• CPC Class Codes: B29C 65/564 hidden in the joint, e.g. dowels or Z-pins B29C65/603 takes precedence
• CPC Class Codes: B29C 65/603 the rivets being pushed in blind holes
• CPC Class Codes: B29C 65/645 using friction or ultrasonic vibrations
• CPC Class Codes: B29C 66/1142 Single butt to butt joints
• CPC Class Codes: B29C 66/30221 said melt initiators being point-like
• CPC Class Codes: B29C 66/30326 in the form of porosity
• CPC Class Codes: B29C 66/43 Joining a relatively small portion of the surface of said articles B29C66/45 takes precedence
• CPC Class Codes: B29C 66/474 said single elements being substantially non-flat
• CPC Class Codes: B29C 66/71 characterised by the composition of the plastics material of the parts to be joined welding bar compositions B29C65/125
• CPC Class Codes: B29C 66/7392 characterised by the material of at least one of the parts being a thermoplastic
• CPC Class Codes: B29C 66/74 Joining plastics material to non-plastics material
• CPC Class Codes: B29C 66/742 to metals or their alloys
• CPC Class Codes: B29C 66/7463 Concrete
• CPC Class Codes: B29C 66/7487 : Wood
• CPC Class Codes: B29C 66/8322 : Joining or pressing tools reciprocating along one axis
• CPC Class Codes: B29K 2023/06 : PE, i.e. polyethylene
• CPC Class Codes: B29K 2023/12 : PP, i.e. polypropylene
• CPC Class Codes: B29K 2025/06 : PS, i.e. polystyrene
• CPC Class Codes: B29K 2025/08 : Copolymers of styrene, e.g. AS or SAN, i.e. acrylonitrile styrene B29K2055/02 takes precedence
• CPC Class Codes: B29K 2027/06 : PVC, i.e. polyvinylchloride
• CPC Class Codes: B29K 2033/12 : Polymers of methacrylic acid esters, e.g. PMMA, i.e. polymethylmethacrylate
• CPC Class Codes: B29K 2055/02 : ABS polymers, i.e. acrylonitrile-butadiene-styrene polymers
• CPC Class Codes: B29K 2069/00 : Use of PC, i.e. polycarbonates or derivatives thereof, as moulding material
• CPC Class Codes: B29K 2077/00 : Use of PA, i.e. polyamides, e.g. polyesteramides or derivatives thereof, as moulding material
• CPC Class Codes: B29K 2711/14 : Wood, e.g. woodboard or fibreboard
• CPC Class Codes: F16B 13/00 : Dowels or other devices fastened in walls or the like by inserting them in holes made therein for that purpose nails F16B15/00; self-locking pins or bolts in general, stud-and-socket releasable fastenings F16B21/00; dowels or bolts for railroad sleepers E01B9/00; ans means for anchoring structural elements or bulkheads specially adapted to foundation engineering E02D5/74; bolts or dowels used while laying bricks or casting concrete sleepers E04B1/38; setting anchoring bolts in shafts, tunnels or galleries E21D20/00; anchoring bolts for shafts, tunnels or galleries E21D21/00
• CPC Class Codes: Y10S 411/90 : Fastener or fastener element composed of plural different materials
• CPC Class Codes: Y10S 411/908 : Resinous material

Abstract

A joining pin (3.2) with which two parts (1 and 2) made from a porous material, particularly wood or a wood-like material, are to be joined together, is anchored in the porous material at predetermined anchoring points (31, 33). For this purpose, a bore (4.2) with a closed inner end (41) is made in the parts (1 and 2). The shape of this bore (4.2) is so matched to the joining pin (3.2) that it can be introduced substantially without force expenditure into the bore and is positionable in a first position. At least one predetermined anchoring point (31, 33) between the joining pin (3.2) and the wall of the bore (4.2) is formed when pressure is built up by pressing the joining pin (3.2) with a pressing force (F) more deeply into the bore to a second position. Energy is supplied in a planned manner to the joining pin (3.2) so that at the predetermined anchoring points (31, 33) the thermoplastic material of the joining pin (3.2) is plasticized. The locally plasticized plastic material is pressed by the local pressure into the porous material of the parts and forms local, macroscopic anchors (10, 20). The joining pin (3.2) is, e.g., made entirely from a thermoplastic material and the energy for plasticizing is supplied thereto by ultrasonic vibration.

Claims

1. A method for anchoring a joining element in a part consisting of porous material, the joining element having a distal end and a proximal end and including a thermoplastic material at least at said distal end, the method comprising the steps of:

forming a bore in the part, the bore having an inner closed end and being matched to the shape and dimensions of the joining element so that the joining element can be positioned in the bore with substantially no force and with the distal end of the inserted joining element disposed against the inner closed end of the bore,

inserting the joining element in the bore such that the distal end of the joining element is disposed against the inner closed end of the bore,

applying pressure to the proximal end of the joining element to force the joining element deeper into the bore, the pressure being applied substantially along a central axis of the bore and producing an increase of pressure of the distal end of the joining element against the inner closed end of the bore,

during the application of pressure, applying vibration energy to the joining element to cause the thermoplastic to plasticize at the distal end of the joining element, the pressure causing the plasticized thermoplastic material to flow into pores of the part beyond the inner closed end of the bore in the axial direction of the bore, thereby forming a macroscopic anchoring connection between the part and the distal end of the joining element.

2. A method according to claim 1 including joining a second part made of a porous material to the first mentioned part with the joining element, wherein the joining element is a joining pin having a reduction in diameter intermediate the ends thereof forming a first shoulder, wherein the step of forming a bore includes forming a portion of the bore through the second part and into the first part to the inner closed end, the bore in the second part having a reduction in diameter forming a second shoulder matching the first shoulder of the joining pin, and the step of positioning includes inserting the joining pin into the first and second parts so that the first and second shoulders are in contact with each other, the contacting first and second shoulders forming a second macroscopic connection between the second part and the joining element.

3. A method according to claim 1 including joining a second part made of a porous material to the first mentioned part with the joining element, wherein the joining element is a joining pin, wherein the step of forming a bore includes forming a portion of the bore through the second part and into the first part to an inner closed end, and wherein the joining pin has an enlarged head portion on the proximal end thereof.

4. A method according to claim 1 including fixedly attaching the joining element to a second part.

5. A method according to claim 4 wherein the step of fixedly attaching is performed after positioning the joining element in the bore.

6. A method according to claim 5, wherein for fixedly attaching the second part, the joining element comprises at its proximal end an internally threaded opening for receiving an attachment of the second part.

7. A method according to claim 1 wherein the step of applying vibration energy includes ultrasonically exciting the joining element to cause the thermoplastic to plasticize.

8. A method according to claim 1 wherein the joining element consists entirely of thermoplastic material capable of being plasticized.

9. A method according to claim 1 wherein the part comprises wood or a woodlike material.

10. A method according to claim 1 wherein the part comprises at least one of sandstone, porous ceramic, burnt brick or concrete.

11. A method according to claim 1, wherein the distal end of the joining element is shaped with a point.

12. A method according to claim 1, wherein the distal end of the joining element is flat or concave.

13. A method according to claim 1, wherein the thermoplastic material is selected from the group consisting of polyamide, polycarbonate, polyester carbonate, acrylonitrile-butadiene-styrene, styrene-acrylonitrile, polymethylacrylate, polyvinyl chloride, polyethylene, polypropylene and polystyrene.

14. A method according to claim 1, wherein the joining element further comprises another material that is different from the thermoplastic material.