Component Made from a Material Consisting Predominantly of Renewable Raw Materials, Having at Least One Compressed Region, and Method and Tool for Producing the Compressed Region

Abstract

The invention relates to a component made from a material consisting predominantly of renewable raw materials, the component having at least one hole with a longitudinal axis (A) and the material being locally compressed in the region peripherally adjoining the hole. According to the method, at least one pin, which comprises a substantially cylindrical shaft and a tip having a reducing diameter in the direction of the component, penetrates into the material, thus creating a hole in the component, and displaces the wood material radially and/or axially, so that the material in the region surrounding the hole is compressed. The tool used for carrying out the method is designed in the form of at least one pin having a cylindrical or polygonal shaft and a tip reducing in diameter in the direction of the component.

Claims

1.-23. (canceled)

24. Component made of a material consisting predominantly of renewable raw materials, characterized in that the component (1) has at least one hole (L) with a longitudinal axis (A1), and in that the material of the component (1) has local compression (V) in the region adjoining the hole (L) on the circumferential side.

25. Component according to claim 24, characterized in that the region of the component (1) adjoining the hole (L) on the circumferential side has radial and/or axial local compressions (V).

26. Component according to claim 4, characterized in that the hole (L) has a diameter (d) and the circumference (dv) of the compressed region adjoining the hole (L) is up to 5×d, and/or the height (hv) of the compressed region is up to 20×d and/or is reduced in comparison with the height (h) of the component (1).

27. Component according to claim 24, characterized in that the hole (L) is a cylindrical or nearly cylindrical hole (L) and is designed as a through-hole in the component (1) or has a bottom.

28. Component according to claim 24, characterized in that the material of the component (1) has at least 50% content of renewable raw materials.

29. Component according to claim 28, characterized in that the material is a wood-based material and in that, if required, less than 50% of other renewable raw materials such as grass-based materials (bamboo) are added to the wood-based material, and/or in that the component (1) is a hybrid material such as wood plastic composite (WPG) with renewable raw materials, and/or in that the component (1) has one or more material layers of metal, plastic, fiber composite material, paper or cardboard or a combination of these material layers.

30. Component according to claim 24, characterized in that the component (1) is designed in the form of a board and comprises at least three layers of renewable raw materials, preferably three layers of wood, which can be combined with further material layers as required.

31. Component according to claim 24, characterized in that the hole (L) is introduced into the component (1) at an angle (b) of 90° to 45° with respect to the upper side (1.1) of the component (1).

32. Method for producing at least one compressed region in a component (1) from a material which consists of at least 50% of renewable raw materials, characterized in that at least one pin (2) penetrates the material of the component (1) and thereby produces a hole (L) in the component (1) and displaces the material radially and/or axially and thereby produces a local compression (V) in the region of the material surrounding the hole (L).

33. Method for producing at least one compressed region in a component (1) from a material which consists of at least 50% of renewable raw materials, characterized in that at least one pin (2) penetrates the material of the component (1) and thereby produces a depression (V) in the component (1) and displaces the material radially and/or axially and thereby produces a local compression (V) in the material.

34. Method according to claim 32, characterized in that two opposing pins (2) are used, which alternately penetrate the component (1) from opposite directions and produce the hole (L) with the diameter (d) and thereby displace the material and compress it in the region surrounding the hole (0, or in that two opposing pins (2) are used and produce a depression in the component from opposite directions and compress the region of the component located between the pins.

35. Method according to claim 32, characterized in that the pin (2) or both pins rotates/rotate at least during penetration into the component (1).

36. Method according to claim 32, characterized in that a return stroke movement of the engaged pin (2) takes place and thereafter a renewed advance stroke movement of the pin (2), in which the pin (2) penetrates further into the component (1), and/or in that during a return stroke movement of a pin (2) an advance stroke movement of an opposite pin (2) into the component (1) takes place.

37. Method according to claim 32, characterized in that a maximum penetration depth of the pin is determined as a function of the component and a rotational speed of the pin and/or a feed rate of the pin, and in that the pin performs a return stroke after reaching the penetration depth.

38. Method according to claim 37, characterized in that the rotational speed and/or the feed rate and/or the maximum penetration depth are determined empirically.

39. Method according to claim 37, characterized in that the maximum penetration depth is determined such that a temperature acting on the component due to the friction of the punch is at most 200° C. (increased from 150° C. to 200° C.).

40. Tool for carrying out the method according to claim 32, characterized in that a) the tool for producing a predominantly radial compression is designed in the form of at least one pin (2) having a cylindrical or polygonal shank (3) and a tip (4) which reduces in diameter in the direction towards the component (1), or b) in that the tool for producing a predominantly axial compression in the direction towards the component has a flat/plane/conical surface with an obtuse angle and/or widens in diameter away from the component.

41. Tool according to claim 40, characterized in that the tip (4) is designed in the shape of a conical tip, a truncated cone or in another shape reducing in diameter in the direction towards the component.

42. Tool according to claim 40, characterized in that a counter-holder is arranged on the side of the component (1) opposite the pin (2) and/or in that the pin (2) is surrounded by a holding-down device.

43. Tool according to claim 42, characterized in that it can be set in rotation by means of a first drive and can be moved in the direction of the longitudinal axis of the pin by means of a second drive, or can only be moved in the direction of the longitudinal axis of the pin by means of a second drive.

44. Tod according to claim 40, characterized in that the pin is heated.

45. Tool according to claim 40, characterized in that it comprises a temperature sensor.

46. Tool according to claim 40, characterized in that the forming tool is cooled during the forming of the axial compression after reaching the final shape or is formed in the hot state.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0077] The invention is explained in more detail below with reference to an exemplary embodiment and associated drawings, wherein:

[0078] FIG. 1 shows the schematic diagram of the method sequence when penetrating the component on one side with a pin,

[0079] FIG. 2 shows the schematic diagram of the method sequence for two-sided penetration of the component with two opposing pins,

[0080] FIG. 3 shows the schematic diagram of a component with radial compression according to the invention,

[0081] FIG. 4 shows the schematic diagram of axial compression according to the invention over the complete connection cross-section of the component,

[0082] FIG. 5 shows the schematic diagram of generating radial and axial compression using a counter-holder,

[0083] FIG. 6 shows the screw connection of two components 1 with axial and radial compression.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0084] In FIG. 1, the schematic diagram of the method sequence during the penetration of the component 1 on one side with a tool which has a pin 2 or is designed as a pin 2, which has a longitudinal axis A2, is shown in the steps A to D. The component 1 is a multi-glued wooden panel (plywood) having a first side 1.1 and a second side 1.2 and a height h. The pin 2 has a cylindrical shank 3 with a diameter D2, which is adjoined by a tip 4 in the direction towards the component 1. The tip 4 is here substantially conical in shape and has a cone angle a, which is preferably between 15° and 20° (but the angle can also be larger or smaller).

[0085] In step A, the rotating pin 2 is moved with the tip 4 in the direction of the upper side 1.1 of the component 1, is seated here on the side 1.1 and is now pressed into the component 1 with a force F in the preliminary stroke, wherein according to step B the material of the component 1 is largely displaced radially and partially compressed. In step C, the pin 2 has penetrated the component 1 and a hole L has been formed in the component 1 by the displacement of the material. Around the hole L, local radial compressions V have been produced over the entire height h of the component 1 by the displacement of the material of the component 1. Subsequently, the pin 2 is removed from the component 1 in a return stroke preferably rotating according to step D in the direction of the arrow. The hole L created in the component 1 has a longitudinal axis A1 and a diameter d, wherein the diameter d corresponds to the diameter D2 of the pin 2. The local compression V surrounding the hole L remains in the component 1 after removal of the pin 2, since this is stabilized by the thermoplastically reacting lignin in the forming region of the material.

[0086] It is also possible for the pin 2 to first partially penetrate the component 1, to be retracted again, and then to penetrate deeper into the component 1 again, thus performing an alternating forward and return stroke movement until the pin 2 has completely penetrated the component 1.

[0087] FIG. 2 shows the schematic diagram of the method sequence with the steps A to D during the two-sided penetration of the component 1 with two oppositely arranged pins 2, the longitudinal axes A2 of which are aligned and which penetrate alternately from both sides 1.1, 1.2 always with a feed into the component 2 until the hole L has formed completely in the component 1 (step C). According to step A, no rotating pin 2 has yet penetrated the component 1. In step B, the upper pin 2 here has entered the component 1 from the direction of the upper side 1.1 of the component 1, but has not yet penetrated it. According to step C, the upper pin 2 has retracted from the component 1 and the lower pin 2 has entered it from the direction of the underside 1.2 of the component 1 and has penetrated it completely and has produced the hole L. Thereupon, the lower pin 2 has also been disengaged according to step D and the method is completed. In the aforementioned examples, the pin 2 is inserted substantially at right angles=angle 90° to the upper side 1.1 or to the underside 1.2 of the component 1. It is also possible to form the pin 2 into the component 1 at a different angle of inclination, thereby creating a hole L whose longitudinal axis A1 runs obliquely in the component.

[0088] It is further possible that the punch is surrounded by a holding-down device which acts on the upper side or underside 1.1, 1.2 of the component 1 during the forming of the hole, depending on the direction from which the pin 2 engages.

[0089] The schematic diagram of a component 1 with a radial compression V according to the invention is shown in FIG. 3.

[0090] A hole L with a diameter d was created in component 1 without pre-drilling. The radial compression V of the material here, which is adjacent to the hole L on the circumference, has a diameter dv of up to 5×d on the circumference. In the example shown, dv is approximately 2×d.

[0091] According to FIG. 4, it is also possible to generate only an axial compression V which extends over the complete connection cross-section of the component 1. The hole L was made by pre-drilling and then the area of the hole L adjoining the periphery of the hole was provided with the axial compression V by an axially acting punch (not shown). The height hv of the compressed region V in the area of the hole L is here approximately 0.5×h.

[0092] FIG. 5 shows a schematic diagram of the generation of a radial and axial compression V using a pin 2 having a shoulder 5 with a diameter D5, which is adjacent to the shank 3, and a counter-holder 6. First, in step A, the radial compression V was generated using the pin 2 and its tip 4, in that the pin 2 enters the component 1 from the direction of the upper side 1.1 and has penetrated it completely, so that the hole L with the diameter d was generated.

[0093] During a further feed, the shoulder 5 is pressed axially into the component 1 (see step B), so that in addition to the radial compression, an axial compression V of the material in the component 1 is produced in the component 1 from the direction of the upper side 1.1, wherein the height h of the component 1 is reduced to a height hv in the region of the acting shoulder 5.

[0094] On the underside 1.2 of the component 1, in both stages, a counter-holder 6 abuts which has a hole 6.1 through which the pin 2 can engage.

[0095] A screw connection with axial and radial compression V is shown in FIG. 6. Two components 1 lie against each other with their flat undersides 1.2 and are connected to each other by a screw 7 and a nut 8, wherein the screw 7 projects through the holes L of the components 1, which holes L are aligned with each other. A washer 9 is provided under the screw head 7.1 and under the nut 8 in each case.

[0096] The compressed region V in the two components 1 allows a higher pretension and reduces the settlement or relaxation and retardation phenomena.

LIST OF REFERENCE NUMERALS

[0097] 1 Component [0098] 1.1 Upper side [0099] 1.2 Underside [0100] 2 Pin [0101] 3 Shank [0102] 4 Tip [0103] 5 Shoulder [0104] 6 Counter-holder [0105] 7 Screw [0106] 7.1 Screw head [0107] 8 Nut [0108] 9 Washer [0109] a Cone angle of the tip [0110] b Angle of penetration of the pin [0111] d Diameter of the hole L [0112] dv Circumference of the compressed region [0113] h Height of component 1 [0114] hv Height of the compressed region [0115] A Longitudinal axis [0116] D2 Diameter of the pin that adjoins the tip 4 [0117] D5 Diameter of the shoulder 5 [0118] F Force [0119] L Hole [0120] V Compression