METHOD FOR PRODUCE STRUCTURAL TIMBER FROM SMALL WOOD AND STRUCTURAL TIMBER

Abstract

The invention relates to a method for producing construction wood from small-dimensioned wood, having the steps of: - providing a small-dimensioned wood log which extends in a longitudinal direction and thereby has a substantially circular cross-section and tapers conically in the longitudinal direction, - separating the small-dimensioned wood log into two half logs, each of which is delimited by a central cutting surface and a parallel outer cutting surface, - trimming the two half logs so as to provide two respective flanks, said two flanks being provided so as to run towards each other along the conical shape of the original small-dimensioned wood log, and - producing a single-layer continuous board by placing and gluing the lateral flanks of multiple trimmed half logs together, wherein the half logs are arranged such that the flanks thereof running towards each other lie against each other in a reciprocal manner.

Description

[0001] Description

[0002] METHOD FOR PRODUCING STRUCTURAL TIMBER FROM WEAK WOOD AND STRUCTURAL TIMBER

[0003] Background of the invention

[0004] The invention relates to a method for producing structural timber, especially from small-diameter wood, and to structural timber produced by such a method.

[0005] In this context, small-diameter wood refers to roundwood from trees with a comparatively small top diameter, typically between 100 mm and 200 mm. Such small-diameter wood is also referred to as "paper wood" because such wood is currently primarily used for paper production. Such small-diameter wood typically has a trunk length of between 1 m and 6 m, preferably between 2 m and 5 m.

[0006] Underlying task

[0007] The invention is based on the object of providing small-diameter wood of the type mentioned with a higher-value use than is the case in paper production. Solution according to the invention

[0008] This object is achieved according to the invention with a method for producing structural timber from small-diameter wood with the following steps:

[0009] - Providing a small-diameter log extending in a longitudinal direction, having a substantially circular cross-section and tapering conically in its longitudinal direction,

[0010] - Splitting the small-sized trunk into two half-timbers, each of which is limited by a central cutting surface and a parallel outer cutting surface,

[0011] - Trimming the two half-timbers, each with two flanks, the main planes of which extend in particular substantially perpendicularly or alternatively preferably at an angle between 55° and 77° to the central cutting surface, wherein the two flanks are trimmed converging along the conical shape of the original small-wood trunk,

[0012] - Production of a single-layer continuous board by placing and gluing several edged half-timbers with their lateral flanks together, whereby the half-timbers are placed alternately against each other with their converging flanks.

[0013] The thickness of the half-timbers is preferably between 45 mm and 90 mm. A stepped thickness, depending on the diameter of the processed small-timber log, of 47 mm (with a minimum top diameter of 100 mm), 67 mm (with a minimum top diameter of 140 mm), and 87 mm (with a minimum top diameter of 180 mm) is particularly preferred.

[0014] When producing the single-layer continuous board, the edged half-timbers are preferably dried first.

[0015] Furthermore, during the production of the single-layer continuous board, at least one step or profile is advantageously formed into the lateral flanks of the edged half-timbers, particularly after the edged half-timbers have dried. This profile preferably forms a step in an otherwise essentially flat surface, the main plane of which extends obliquely to the central cutting surface. The angle between the central cutting surface and the main plane of this profile or flank surface is preferably between 55° and 72°, depending on the diameter of the processed small-diameter log.

[0016] The method according to the invention for producing structural timber from small-diameter wood preferably further comprises the step of separating at least one panel strip from the endless panel with strip flanks that are essentially parallel to one another, in particular with a width of between 8 cm and 30 cm.

[0017] Furthermore, the method for producing structural timber from small-diameter wood according to the invention is advantageously further characterized by the step: producing an endless panel strip by successively applying and gluing several panel strips, wherein the panel strips are provided at their ends in particular with prongs.

[0018] Furthermore, the method for producing structural timber from small-diameter wood according to the invention further comprises the step of planing the continuous panel strip to a final die size.

[0019] Finally, the method according to the invention for producing structural timber from small-diameter wood preferably also includes the step of producing a beam by arranging and gluing several continuous panel strips that have previously been cut to a predetermined length.

[0020] The invention also relates to structural timber produced by such a method. Brief description of the drawings

[0021] An exemplary embodiment of the inventive solution is explained in more detail below with reference to the attached schematic drawings. It shows:

[0022] Fig. 1 an explanation of working steps of an embodiment of the solution according to the invention,

[0023] Fig. 2 is a partial, frontal plan view of a small-sized timber for processing according to the method of the invention.

[0024] Detailed description of the embodiment

[0025] Fig. 1 shows an embodiment of a method 10 for producing structural timber 12 from small-diameter wood 14. The method comprises a step 16 in which a small-diameter wood log 18 is provided, which extends in a longitudinal direction, has a substantially circular cross-section 20, and tapers conically in its longitudinal direction (not shown). The small-diameter wood log 18 preferably has a diameter at the top (thin end) of between 100 mm and 200 mm and / or a diameter at the butt (thick end) of between 124 mm and 224 mm. In step 16, the small-diameter wood log 18 is then further split into two half-timbers 22, each defined by a central cutting surface 24 and a parallel outer cutting surface 26.

[0026] In a step 28, the half-timbers 22 are trimmed or laterally milled, with this trimming or milling of the two half-timbers taking place conically, with two flanks 30 each, the main planes of which extend perpendicular to the central cutting surface 24. The two flanks 30 converge along the conical shape of the original small-diameter trunk 18. This is followed by a step 32 in which the wood prepared in this way is first dried to a residual moisture content of preferably between 12% and 20%, particularly preferably between 15% and 18%, and then, in a step 34, provided with a profile or step 36 in each of the flanks 30.

[0027] In a step 38, the thus trimmed and profiled half-timbers 22 are placed alternately against one another with their lateral, converging, profiled flanks 30. The thus pre-processed half-timbers 22 are then glued together at their profiled flanks 30 to form a single-layer continuous panel 40.

[0028] In a step 42, individual plate strips 44 are then separated from this single-layer endless plate 40, each of which has strip flanks 46 parallel to one another.

[0029] The individual strip flanks 46 are then, in a step 48, provided with prongs 50 at their ends, in particular in the form of a longitudinal finger joint, placed one behind the other, and then glued together at the prongs 50. This creates a continuous strand or continuous panel strip 52 from panel strips 44, which is then, in a step 54, cut to a predetermined length and planed to a final plank dimension 56, thereby producing a so-called structural solid timber or a lamella 58.

[0030] Finally, such lamellae 58 are then stacked and glued together to form a beam in the form of a glulam beam 60 (laminated timber beam), a duo beam 62, or a trio beam 64. Alternatively, a so-called cross-laminated timber 66, particularly of CLT quality, can also be produced in this way. Fig. 2 shows a partial end view of a small-diameter timber log 18, with a top radius 68 and a stock radius 70 marked. A saw cut 72 forms a half-timber 22 with its central cut surface 24 and, opposite, its outer cut surface 26. Fig. 2 further illustrates an angle 74 already mentioned above between a main plane 76 of the step or profile 36 and the central cutting surface 24. This angle 74 is advantageously between 55° and 72°, in particular between 60° and 65°, depending on the diameter of the processed small-wood trunk.

[0031] Finally, it should be noted that all features mentioned in the application documents and in particular in the dependent claims, despite the formal reference to one or more specific claims, are to be granted independent protection, even individually or in any combination.

[0032] List of reference symbols

[0033] 10 Methods for producing structural timber

[0034] 12 Structural timber

[0035] 14 Weak wood

[0036] 16 Step Preparing and splitting small wood trunk

[0037] 18 weakwood trunk

[0038] 20 Cross section

[0039] 22 half-wood

[0040] 24 Central cutting area

[0041] 26 Outer cutting surface

[0042] 28 Step Trimming

[0043] 30 flank

[0044] 32 Step Drying

[0045] 34 Step Profiling the flanks

[0046] 36 Grading or profiling

[0047] 38 Step Gluing

[0048] 40 single-layer continuous plate

[0049] 42 Step Separating Plate Strips

[0050] 44 plate strips

[0051] 46 striped flank

[0052] 48 Steps: Dovetailing and Gluing Panel Strips

[0053] 50 prongs

[0054] 52 endless strands or endless plate strips

[0055] 54 Step Cutting and Planing

[0056] 56 Dieken gauge block

[0057] 58 lamella or solid structural timber

[0058] 60 glulam beams

[0059] 62 Duo-Beam Trio-Beam Cross-laminated timber End radius Stock radius Saw cut Angle Main plane of the grading or profiling

Claims

-9- Claims 1. Method (10) for producing structural timber (12) from low-grade timber (14) comprising the steps: - Providing a small-diameter log (18) extending in a longitudinal direction, having a substantially circular cross-section (20) and tapering conically in its longitudinal direction, - Splitting the small-diameter log (18) into two half-logs (22), each bounded by a central cross-sectional surface (24) and an outer cross-sectional surface (26) parallel to it, - Trimming the two half-timbers (22) with two flanks (30) each, wherein the two flanks (30) are trimmed converging along the conical shape of the original small-timber trunk (18), - Producing a single-layer continuous panel (40) by placing and gluing several edged half-timbers (22) together with their side flanks (30), wherein the half-timbers (22) are placed alternately against each other with their converging flanks (30).

2. Method for producing structural timber from low-grade timber according to claim 1, wherein, in the production of the single-layer continuous panel (40), the edged half-timbers (22) are first dried.

3. Method for producing structural timber from low-grade timber according to claim 1 or 2, wherein, when producing the single-layer continuous panel (40), at least one step (36) is formed on the side flanks (30) of the edged half-timbers (22), in particular after drying the edged half-timbers (22).

4. Method for producing structural timber from low-grade timber according to one of claims 1 to 3, characterized by the step: - Separating at least one strip of plate (44) from the continuous plate (40) with strip flanks (46) that are substantially parallel to each other.

5. Method for producing structural timber from low-grade timber according to claim 4, characterized by the step: - Producing an endless strip of plates (52) by placing and gluing several strips of plates (44) one after the other, wherein the strips of plates (44) are provided at their ends in particular with tenons (50).

6. Method for producing structural timber from low-grade timber according to claim 5, characterized by the step: - Planing the endless strip of boards (52) to a final dimension (56).

7. Method for producing structural timber from low-grade timber according to claim 5 or 6, characterized by the step: Production of a beam (60, 62, 64) by arranging and gluing together several continuous strips of plate (52) that have been previously cut to a predetermined length.

8. Structural timber (12) produced according to a method according to any one of claims 1 to 7.