FI77805C - Procedure for the production of profile pieces from saw timber. - Google Patents

Description

77805

Method for making profile pieces from sawlogs

The invention relates to a method for producing profile pieces of a certain length by sawing the log in full length into slices and the slices according to the intended use into log-length blanks, from which the final cross-sectional shape of the profile is planed.

In particular, the invention relates to the production of wooden profile parts of a window or similar types of e.g. frame and door frame profile parts from selected saw supports so that the quality of different parts of the wooden frame is taken into account in accordance with the long-term durability and appearance requirements of the window or door.

The usual way to make windows, frames or door frames is to use normal lumber as a raw material. There have been problems with normal lumber in the manufacture of windows that are quality and cost conscious.

A very common way in the sawmill industry is to sort logs in terms of size and quality, and then saw as a so-called four-sawmill to standard dimensions and further sort the sawn timber into standard quality classes. More flexible methods for making non-standard customer products have also been developed. In general, sawing is based on the utilization of a healthy-branched top part of a tree trunk, a dry-branched intermediate part and a low-branched or even branchless base part. However, the base parts are often quite conical.

A conventional method of manufacturing windows well known in the art is to profile product parts from blanks that have only been cut to an almost final extent. There are many drawbacks to this method, especially when preparing in small batches the so-called tailor-lined windows.

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The raw material requirements for windows consist of the as branchless and straight sawn timber blank as possible for the inner and intermediate frame, the weatherproof and healthy straight sawn timber blank for the outer edge of the outer frame and frame, and the less important usually three or more glued sawn timber blanks. The above-mentioned weather resistance is generally ensured by using e.g. salt-impregnated lumber. Good weather resistance can also be achieved by using pine heartwood in critical parts outside the window, which has long been known.

The problems mentioned in this connection when using normal sawn timber consist in that a) The branchless surface layer of the base part of a good quality frame, due to the conicity of the wood, has to be partially removed, e.g.

b) Further due to conicity, sawn timber often comes for oblique reasons.

c) The proximity of the wood core is indeed weather-resistant heartwood, but often black-branched and poor wood that has to be removed.

d) As the final product is only cut from a blank that is shorter than the log, a large number of wastes result.

It has also been suggested to use a non-nsli sawing to start logging. Finnish patent 6108 discloses sawing into boards along one defined side of the frame. However, none of the above requirements can be met, and the method has the same disadvantages as normal quadrature sawing.

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Finnish patent application 855042 describes, from the above-described issues, the cutting of a tree trunk into blanks determined in terms of length, width, thickness and quality required by the user. Patent application Θ55042 is based on the above-mentioned manufacture of a conventional product (e.g. a window) as well as a very expensive sawing process, which is also difficult and expensive to control and control production.

The method according to the invention provides a decisive improvement in the above-mentioned drawbacks. To achieve this, the method according to the invention is characterized by what is set forth in the characterizing part of claim 1.

The advantages of the invention compared to the conventional sawn timber method include: 1. The quality of the wood raw material (heartwood / surface wood, branches, etc.) can be optimized according to the intended use of the profile blanks.

2. The structure of the wood (autumn direction and straightness, etc.> can be implemented by pre-sawing according to the intended use of the product.

3. The working margin required for profiling blanks can be defined in accordance with practical minimum requirements.

4. The production of blanks can be concentrated on efficient and programmed sawing machines and equipment. A variable-blade multi-blade saw is often sufficient as an additional investment.

5. It is possible to maximize the value yield of the saw log and during the sawing process the log cutting method can be corrected if necessary.

4 77805 6. The proportion of quality defects caused by drying is minimized.

7. The production of "tailor-made" windows is quite easy to automate, the throughput is fast and the control is easy.

Θ. The functional and visual quality level of the windows can be determined by using purpose-sawn blanks, so that there are no rejectable quality defects in the production.

In the following, the invention will be described in more detail with reference to the accompanying figures.

Figure 1 shows parts of a tree trunk in principle; Figure 2 shows the profiled parts of the window frame in cross section; Figure 3 shows parts of a sawn slice of a tree trunk in principle; Fig. 4A shows a log-length blank according to the invention; Fig. 4B shows a Log-length Profile according to the invention, from which profile pieces of product are obtained after cutting; Figure 5 shows Slicing of a tree trunk; Fig. 6 shows a typical sawmill for carrying out the method according to the invention; Figure 7 shows the sawing of blanks from a log-length slice according to the invention; Figure Θ shows a production phase diagram according to the invention.

Figure 1 shows the above-mentioned top part 1, intermediate part 2 and base part 3 of the frame 1Θ. In the conventional way, the structure of the obtained wood slice often consists of a branchless surface layer 7, an oblique part Θ and a possible black-branched heart part 9, as shown in Fig. 3.

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Figure 2 shows the location and shape of the profile parts of a conventional window frame. The window frame consists of a pig frame 4, an intermediate frame 4 ', an outer frame 5 and a frame part 6 glued in several parts. The different sections of the profiles have the quality requirements described earlier.

According to the invention, after substantially peeling and cubing measurement, the mainly good quality heavy pine log 1Θ is sawn according to Fig. 5 with conventional sawing machines into three or more parts, core slices 13 and surface slices 14. Some sawing machines have to be sliced in two or more steps.

Next, at least the core slices 13 are sawn according to Figure 7 along the outer edges of the slice into blanks 15, 16, which may be only one, but typically at least two, leaving a slightly wedge-shaped piece 17 in the middle of the body, which is a waste piece if it is a defective wood 9. or it is utilized otherwise. Since sawing at this point takes place at the outer edges, you. parallel to the surface of the wood, the blanks thus obtained are of the same size in size and for direct reasons. The reason for this is that each blank remains in the same depth zone throughout its size.

The resulting sawn blanks are graded, processed and dried in the same way as normal sawn timber.

Next, the thus obtained blanks 15, 16 with different grain structure and other properties, but with uniform quality, are still planed into their final profile shape, still remaining in full log size. Blanks 15 of the same type, which are surface wood, are made, for example, into an inner and / or intermediate frame profile, and blanks 16 which are different but similar to each other are made into an outer frame profile or the outer surface profile of the frame. Thus, depending on the dimensions of the een and the intake point in the tree trunk, the nearly square cross-section blank shown in Fig. 4A can be planed, e.g. the outer frame profile 5, etc.

Only the log-length final profile 19 obtained in this way is cut into final product parts 10, as shown by the broken lines in Fig. 4B. In connection with cutting, the joints of the ends of the product parts are machined with a machining cutter in the same work step, after which the final product can be assembled.

Depending on the appearance requirement of the final product, the profile can be extended in the above-mentioned manner by a suitable installation method, such as a glued finger joint, from the end of the profiles opposite to the cutting point. In this case, in principle, the product parts are cut from an endless profile, so that no cutting loss occurs at all.

When using extension, an additional feature is that if individual defects are found in the profile, they can be cut off and the resulting ends of the intact profile parts can be joined together by a splice, thus obtaining an intact endless profile. Also, the heartwood, which is very resistant to weathering, often close to the weather wedge core in the middle of the slice, can be utilized excellently using further technology.

If it is expedient to make the final profile from the side profiles glued to each other along the entire length, such as the frame 6, the sub-profiles 6a to 6d are glued to each other in the length of the log and only the final profile 6 is cut to the required length of the final product. If, in connection with such a structure, it is desired to remove the defective points in the sub-profiles 6a to 6d, they are removed from those sub-profiles, the sub-profiles are glued together to obtain the final profile shape, which is cut along the end product. Depending on the desired dimensional accuracy, the final planing of the profile can be done either just before cutting after gluing the sub-profiles 7 77805 or the oea profiles have been planed to the final dimension before gluing them together.

It is typical of the present invention to make the most of the equipment already available in sawmills. As one application example, Fig. 6, in which a previously known variable-etched multi-blade saw 11, characterized by the use of the invention, with its return conveyor 12 is placed in connection with a very typical circular saw line. Thanks to the method described in more detail above, the invention has the potential to improve the profitability of the entire sawmill and window industry and to ensure the qualitatively optimal use of wood raw material.

Claims (4)

77805 β A method for producing profile pieces of fixed length by sawing a log in full length into slices and slices according to the intended use into log-length blanks from which the final profile cross-sectional shape is planed, characterized in that log-length blanks <15, 16) with respect to the grain structure of the wood and the surface wood / heartwood, the weather resistance and appearance requirements of the part of the blank to be used and that the blanks <15, 16) are the length of the log or longer, after which the profiles are finally cut to the length of the product parts <10). Method according to Claim 1, characterized in that the defects <15, 16) are removed from the blanks by cutting the blank on both sides of the defect and joining the resulting free ends with a finger joint and continuing the blank by gluing and finger joints to a sufficient length before planing the blank or its component. the cross-sectional dimensions. Method according to one of the preceding claims, characterized in that the blank is extended by an extension joint with the planing and cutting of the second part of the profile in parallel with the second end, cutting profile pieces <10) in length from the first end to obtain a blank almost infinite in length. Method according to one of the preceding claims, characterized in that in connection with the cutting of the profile, the notch of the corner joint is in each case machined to the length length according to the product by the same machining. li 9 77805 Pftt.entKrfty