FI69977C - FOERFARANDE VID BEARBETNING AV SAODANA STOCKAR SOM HAR MOT ROETAENDAN OEKANDE DIAMETER OCH ANORDNING FOER TILLAEMPANDE AV FOERFARANDET - Google Patents

Description

69977

Method for machining logs whose diameter increases towards the base and apparatus for applying the method

The invention relates to a method as described in the preamble of appended claim 1 and to an apparatus for carrying out the method. In this case, flat reduction and sawing equipment means the reduction saw described in Finnish Patent Publication No. 56,941, in which the reduction and sawing operations are combined in one machine and a separate flat reduction machine and a separate (shared) sawing machine along a common center line.

Handling boards in sawmills is very laborious. Boards that are not completely good, e.g. form-15 mat sharp-edged boards or boards with so-called webs (not perfectly good points in the middle areas of the flat surface of the board) then cause special problems, e.g. stops (breaks). Stops in the sawmill's conveying equipment are assumed to cause losses of about 5-10% during working time, with many such stops being due in particular to boards with sharp ends or webs being skewed on conveyors and feeders. Therefore, it is very important that such defective boards are removed from the production process as soon as possible and discarded, i.e. chipped. But since wood chips are much less valuable than processed wood, it is at the same time important that only those parts of the wood for which it is absolutely appropriate are felled.

However, there are two main reasons why relatively large quantities of lau-30 must have to be discarded: a) Raw material, ie logs are sorted by diameter into so-called centimeter categories, ie all logs with a diameter within certain limits given in whole centimeters inside, are included in one centimeter-35 ri class. The program for placing the saw blade in its frame (adjusting the position of the saw blade laterally) is each adapted to the upper limit of the class, so that when machining logs, 2,69977 with a lower diameter, most of the deformed pieces of wood are forcibly produced.

b) Logging of logs, strong branches, ovality, etc. increase the proportion of rejected pieces of timber.

5 The introduction of the reduction sawing method, which will be explained in more detail below, has brought about a considerable improvement in the sawmill technique, so that the external parts of the logs that would otherwise form so-called surfaces are immediately reduced to chips. Nevertheless, some of the problems remain unresolved, because about 50-70% of the outer boards, which are obtained after planar milling in a saw in a reducing device, have to be discarded due to their deformity before they enter the edging device, or at the latest in the edging device. However, sorting after surface milling in a reducer requires extra labor.

German Patent Application No. 29 47 993.4 et al. In the corresponding Swedish patent application 20 No. 8 008 297, it has already been proposed to take into account the conical shape of the logs, tapering from the base to the end, when feeding the logs, so that during feeding the log width is continuously sensed by two sensing pins cooperating with a hydraulic or pneumatic device. that when the side felling of the cutting tools becomes so large during the machining process that an additional side board can be obtained from each side of the log, the distance between the cutting tools is increased during machining 30 and the cutting device passage by twice the board thickness and twice the cut. It is thus achieved that the wood material, which would otherwise have been converted into less valuable chips, becomes a sideboard with an excess of more than 35 on both sides of the reduced log. However, not all the additional sideboards obtained in this way are useful, as some of them have to be discarded and then this method is 3 69977 more complicated and more costly than if the corresponding volume of wood had been initially chopped with cutting tools (reduction plates). In order for a board to be approved, it is not enough for it to have a certain minimum thickness, but it must also have a certain minimum length and nominal width. This method thus gives three types of products from the sides of the log: wood chips, acceptable extra sideboards and undersized extra sideboards (eg only 10 cm 10 long and / or 2 cm wide) which have to be sorted, removed from the product line and chipped separately in one on a device other than the reducer. In addition, it may happen that the log may, for example due to its irregular shape, provide a longer additional sideboard 15 on one side than on the other, which, however, is not taken into account according to this method.

It is an object of the present invention to provide a method and apparatus which allows only two types of products to be obtained from the side parts of logs, namely wood chips and only acceptable additional sideboards, and also to provide an additional sideboard of maximum length on each side of the log. it is possible on the opposite side of the log. This eliminates the need to sort the extra sideboards obtained and, as a separate step, to chop the undersized extra sideboards into chips. In addition, the highest possible yield is obtained when the extra board obtained from each side of the log has the greatest possible length.

30 This task is solved in accordance with the appended claims. According to the invention, the outer contours of the log as seen in plan view and its length with respect to the reference line are first determined. Several devices for determining the profile of a piece of wood are known and described in the patent literature. A simple measuring device for this purpose is presented later in the present description. The reduction plates are then placed so close to each other that from the first impact at the narrower top end of the log they each begin to block on their own side a planar side surface which is perfectly acceptable along its entire length as a flat baffle, i.e. free of web and nowhere. set minimum surface width.

However, as the diameter of the log gradually increases from the narrower top end to the wider base end, it may happen that so much 10 material is milled away from the base end of the log that it would be sufficient for an additional outer board, albeit shorter than the entire log. There is a standardized minimum length for usable boards, e.g.

1.8 m, while the supports themselves have a much longer length, e.g. 4 m. If the additional outer board were to be shorter than the minimum length of 15 m, it has been expressed that it is actually milled away, i.e. the reduction plates chop it into chips. However, if it corresponds to at least the minimum length, then according to the present invention the reduction plate on said side moves outwards by a predetermined distance (selected thickness of the additional outer board plus width of the slot) and the log has a stepped or stepped side surface. The extra saw blade then separates the shorter extra board after the step from the rest of the block in the usual way. The procedure may be repeated.

All calculations necessary for the above operation are performed in a conventional manner on the basis of the data entered in the electronic measuring and control unit with the result that either no control signal is produced to move the second or second reduction plate or that such a control signal is produced when at least the minimum length remains -reducible on that log page. Thus, all the extremities of the log, which ultimately have to be chopped, have been converted to chips directly during planar reduction, while all the extremes of the log from which at least 5,69977 of acceptable lengths of minimum length, width and thickness can be obtained have been recovered. Said distance by which the reduction plate is moved outwards can also be determined during the calculation phase in the measuring and control unit, where the optimization of the possible additional outer board length, width and thickness dimensions is achieved by means of a pre-entered program for this purpose.

The invention will now be described in more detail with the aid of the accompanying schematic drawings, in which Figure 1 shows a part of a conventional reduction saw machine 10 in which the log is machined, Figures 2a and 2b show two typical outer boards with defects Fig. 4 is a flow chart of the method according to the invention, Fig. 5 shows a plan view and on a smaller scale than Fig. 1 the machine according to Fig. 1 in the device according to the present invention, and Fig. 6 is a flow chart of Fig. 5 operation diagram of the electronics unit of the device according to

Figure 1 shows a reduction saw machine according to Finnish Patent Publication No. 25 No. 56,941, comprising a reduction part 50 and a saw part 40 having a common center line CL. The log 10, the center line of which is CS, must be flat-reduced on both sides and then cut into several parts. The log 10 is fed forward gold-30 conveyor 13 the direction of arrow A direction between the two hakkeenhakkuu- a redusointilevyn 11, 12, which mills off and the batter chips outer header portions 10 ', 10', which by the way, that is. Only saw processing, form surfaces which have separate and hack off.

The reduction plates 11, 12 are each located on their drive shafts 11a, 12a, which are driven by an electric motor (not shown). Conventionally, the reduction plates 11, 12 6 69977 are in the longitudinal direction (double arrows B) e.g. for distance from each other when a new log has to be received, after which they are immediately returned to a predetermined distance I for the entire reduction operation.

Between the reduction plates 11, 12 and the saw device 40, planar guide members 23, 24 are arranged, which can also be moved apart and towards each other.

After leaving the reduction plates 11, 12 and passing the guide member 23, 24, the log inlet 10Ϊ arrives in block 10a behind the inlet end 10aan of the reduced log to the next saw section 40, which in the example shown is a band saw device comprising four conventional band saws shown in Fig. 5. 14, 15, 18, 19, each passing through rollers 14a, 15a, 18a, 19a 15 arranged on its shaft 14b, 15b, 18b, 19b, while in Figure 1 only the inner arms 14 ', 15', 18 'of these saw blades are shown. , 19 '.

In the sawing device 40, the block 10a is sawn through the so-called central piece 22, into two inner boards 20, 21 and 20 into two outer boards 16, 17, which are separated from each other by sawing slits (saw seams) 20a, 21a, 22a, 22b.

The outer boards can then have the appearance of Fig. 2a or 2b, in which the broken outlines show the parts which, according to the present invention, are rolled away, while they would remain in a conventional reducing saw device. At the wider working end lOr of the log and the board, the outer board is generally perfectly good, however, in the vicinity of the top end lOi it often has areas b where a certain minimum surface width h ^ falls below, or so-called uu-30 areas c. According to the present invention, the undersized parts are milled out as will be explained in detail later, and after a step or step z in which the width I increases in a jump-like manner, areas a are obtained from which one additional outer board 35 can be made if a completely good piece of log length 1 remains at least in advance. of a specified minimum length m. about. The present invention thus solves the task of min 7 69977 to produce only perfectly good outer boards, while the support parts, such as b, c, which would give defective outer boards, are chipped before leaving the reduction saw, i.e. in the same way as hitherto. occurred in conventional reduction saws only on surfaces, i.e. log sections 10 'and 10 ".

Figure 3 shows a cross-section of the log 10 along the plane III-III of Figure 1. The cross-section has been turned 90 ° for the sake of clarity so that it is in the plane of the drawings and all incoming section lines are drawn in cross-section. The reduction saw machine is shown in a somewhat modified embodiment, in which the saw part is located in close proximity to or inside the reduction part 50, so that the structural length of the device is shortened 15 and in particular the control members 23, 24 between the two parts (Fig. 1) can be omitted.

The distances from the center line CL of the machine tool 40, 50 to the two outermost side points of the log are x1 and X2 and are measured in the above-mentioned profile recognition device.

20 The center line CS of the log is usually not exactly located on the center line CL of the machine tool. The width of the surface h1 and vast, h2, while s1 and s2 are the distances centerlines CL from the inner edge of the outer saw blades 14 ', 15'. The distances s1, s2 are determined by the so-called positioning program. The values t 1 and t 2 are the thicknesses of the outer 25 boards 16, 17, including the sawing slots 20a, 21a inside. The notations y1 and y2 indicate the thickness of the surfaces 10 ', 10 ”(Fig. 1) which the reduction plates 11, 12 mill off. It can be seen from Figure 3 that the following relations apply between the mentioned quantities: Χχ = y-L + t1 + s1 (la) x2 = y2 + t2 + s2 (lb)

It can be seen from Figure 4 that, according to the method according to the invention, the values x1 and x2 are first measured, which takes place in a known device for this purpose. The measurement results are fed to an electro-nick unit, which is also of a type known per se.

8 69977 This electronic unit is programmed to perform the operations according to Fig. 4, and for this purpose the values hm ^ n · ^ and ^ min2 have been entered into the unit for the minimum permissible surface widths (usually 5 h.. = H. ~). When the first or second reduction plate has to step outwards, it means that it is moved away from the center line CL to position 11 'or 12' (Fig. 3).

When either of the dimensions x1, X2 exceeds a certain value, the plane-reduced outer surface of the log, which at the same time forms the outer planar surface of the outer board, becomes narrower than required by a predetermined minimum surface width dimension hmj_ni (e.g. 75 mm). The reduction plate 12 remains in its inner position and all the wood material which would form an error-free outer board is reduced. As soon as the distance of the reducing plate from the center line CL falls below said critical value / dimensions x1, X2 increase with the log forward feed rate, as the diameter of the log (x ^ + X2) increases the closer to the base end and at the same time corresponds to the remaining 20 unreduced logs length m is at least the minimum dimension m determined according to Fig. 2a and fed to the electronic unit. (Fig. 2b), the reduction plate 12 steps outwards, preferably after a certain pre-programmed deceleration, and the material is obtained on an additional outer board. The same goes for the values of t-, s ~, h. ~ and redu-

^ 2 '2 mm2 J

relative to the sounding plate 12. The remaining log length is obtained in the electronics unit by subtraction m = 1 - 1 '(2) where 1, 1' and m represent the quantities shown in Figure 2b, 1 of which has been fed to the electronics unit 100 before the operation step and 1 'has been calculated by means of the signals supplied via Fig. 3) on the one hand for bypassing the optical barrier 38, 39 of the top end, on the other hand for the speed of movement of the conveyor 13.

35 If the web c (Fig. 2b) is located at a shorter distance from the base end 10r than what is the minimum dimension m ^^, 9 69977, then the reduction plate remains in its inner position at all times. For example, the following three cases may occur: A) At a certain length 1 'from the top end 10i, the reduced block 10a has a sufficient surface width and this 5 is maintained at least for a minimum length m. .

J mm B) The width of the surface is sufficient at the apex end lOi, but not in the central region closer to the base end, where the minimum value h. , undershot, mml C) The width of the surface is sufficient for the entire length 1, 10 but the web c occurs closer to the base end lOr than the minimum length m. is. r mm

In all three cases, the reduction plates 11, 12 are in their inner position when the log 10 arrives at the reduction device. In cases B and C, they remain in it throughout the leveling-15 tuning operation, while in case A they move outwards at a certain point in time. It should be noted that the log profile is determined on each side of the reference line CL separately. If this profile is asymmetrical and this is especially the case with the logs of the loops, then the reduction plate will move outwards perhaps only on one side or at different times on each side.

Figure 5 schematically shows an embodiment of a device for carrying out the method according to the invention. The device comprises a conveyor 13 for feeding the log 10 forward, which is held on it by the retaining rollers 29, 30. In this case, the log 10 is sensed by two sensors located in front of the reduction plates 11, 12 of the device. These sensors form the profile measuring device mentioned at the beginning and they each consist of one pair of sliding shoes 27, 28 and 17, respectively.

21 ', 28'. Their function is to determine the longitudinal contours of the log 10 and their position with respect to the reference line, in the example shown, the center line CL of the device (dimensions, x2). In principle, one of the two sensors shown is sufficient and, of course, another known mechanical or optical sensor can also be used.

10 69977

The output signals of the sensors are fed to the lines d2 and d1 and resp. via d2 * and d2 'to an electronic measuring and control unit 100 of a conventional type (computer), the operation of which will be explained in detail later.

An optical barrier is arranged between the position sensing elements 27, 28 and the reduction plates 11, 12, comprising a light-sensitive element 38 and a light source 39 and which, via a line d1, introduces a signal to the electronic unit 100 indicating the passage of each log inlet end 10. At a known feed rate, it can be used to calculate the longitudinal position of the log in time.

A line corresponding to the movement of the carrier 13 is further fed to the electronics unit 100 from the sensor 13a via the line d4. On the basis of the information entered via the lines d ^ _4, the profile of the log 10 can be "re-created" in the electronic unit 100 in a known manner. Preferably, the log 10 is felt in front of the reduction plates 11, 12 corresponding to a selected part of the log length 20 (such as half, third part, etc.), which is not shown in Figure 5 due to lack of space. This can of course also be combined in front of the reduction plates shown in the drawing. with recognition. In the case of a log length of 1 e.g.

25 4 m, the sliding shoes 27, 28 should thus be located at least 2 m in front of the reduction plates 11, 12 in order to ensure that any web c (Fig. 2b) has time to be detected. The reduction plates are mounted on bearings (not shown) via their shafts 11a, 12a and are rotated in a manner not shown. Always a corresponding position control means, such as a double-acting cylinder piston device 31, 32, can move the reduction plates farther apart and closer to each other.

The guide members between the reduction plates 11, 12 and the saw blades 14, 15, i.e. in the example 35 shown in the guide plates 23, 24, must of course also be displaceable in the same way as the reduction plates. This can be done either by automatically participating in the movement of the reduction plates 11 69977 by being influenced by the position control means 31, 32 of the reduction plates, or preferably by being controlled by their own position control means 23A, 24A by separate lines ff and gg 5. is controlled by the electronics unit 100. The members 23A and 24A may advantageously also be double-acting cylinder-piston devices. The electronic unit 100 is then programmed so that the guide plates 23, 24 perform a transfer in the same way as otherwise in the same direction and to the same extent as the reduction plates, but with a predetermined deceleration during stepping. Thus, it is provided that these control means also control the block during the time interval before the step z (Fig. 2), which is formed on the countercurrent edge of this plate during stepping out of the reduction plate, reaches the countercurrent edge of the control plate, i.e. the deceleration is selected so that at a given feed rate corresponds mainly to the distance represented by the inner diameter d of the reduction plates.

The electronics unit 100 can further advantageously be programmed to receive both reduction plates 11, 12 and control plates 23, 24 simultaneously in the same direction when receiving signals from a sensing device which mark a loop log with e.g. a center line Cg '. bringing 25 to follow the logging of the log. This uniform displacement is deposited, or is only, combined with the outward stepping of the second or second reduction plate caused by the increasing diameter of the log in exactly the same way as in the case of straight logs. Thus, it is also possible to rationally machine loop logs in accordance with the present invention. In the example according to Figure 5, both reduction plates 11, 12 and guide plates 23, 24 would be shifted equally to the right, corresponding to the deviation between the center lines and Cg '.

35 The entire sensor - regardless of how many points along the length of the log are felt - may also be located in a place other than the direct connection of the i2 69977 timber machine itself and may be long enough with the relatively short wires d £, d ^, etc. shown in Figure 5. instead of connected to the electronics unit 100.

A saw section 40 is arranged behind the reducing part 50 of the apparatus. Each of the four band saws of the saw section 40, of which only the saw blades 14, 15, 18, 19 each surround their upper turning roller 14a, 15a, 18a, 19a and located on the shafts 14b, 15b, is shown in the drawing. , 18b, 19b, are mounted on the base plate 14c, 15c, 18c, 19c movable towards and away from the center line CL. The movements of the base plates are effected by means of positioning means, e.g. double-acting hydraulic cylinder piston devices 34-37, which are fixedly fixed at one end and connected to the base plate at the other end.

Means 34-37 thus allow each saw blade to be individually adjusted in position relative to the centerline CL; this adjustment is called setting the saw blade. Mi-20, if desired, this setting program can be given automatically to the electronics unit 100 via wires d 1.

The position control means 31, 32 of the reduction plates 11, 12 are connected via wires f, g to the electronic unit 100 for receiving the control signals produced in this unit.

Fig. 5 shows the situation shortly after the reduction plates 11, 12 have been moved outwards, so that additional outer boards 16 ', 17' are obtained, as indicated by the broken lines 2a ', 21a', which show sawing slits, which saw blades 14, 15 bring about.

It should be noted that these saw blades 14, 15 have previously swept past, more specifically, swept along the plane-reduced outer surfaces of the boards 20, 21 and then cleaned these, thus avoiding that the boards 20, 21 have outer planar surfaces with partially - before the reduction plates 11, 12 have been moved outwards - the surface structure resulting from the reduction i i 69977, while in them in part - after the reduction plates 11, 12 have been moved outwards - is the surface structure resulting from sawing.

The thickness of the additional outer board can, of course, be selected from suitable standardized board thicknesses, taking into account on the one hand the dimension x ^ (Fig. 3) of the log half, and the remaining log length m. Thus a thinner board can be taken than the currently preferred thickness, if it is found that the preferred thickness 10 exceeds the so-called. stuagen rajan.

Based on Figure 3, the following equations can be written, which give the values of h - ^ and vast, h2. The reduction plates 11, 12 step outwards when the conditions (6a), (6b) and (7) are also satisfied.

15 (0.5 hx) 2 = ^ + x2 - y1) y1 (3a) y-j_ = Xj_ - s1 - t1 (4a) which gives: h1 = 2 V (x2 + s1 + t1) (χι - s1 - t ^ (5a) (0.5 h2) 2 = (χ1 + χ2 - y2) - y2 (3b) 20 * 2 = x2 'S2 ~ fc2 (4b) which gives: h2 = 2 V (χ1 + s2 + t2 ) (χ2 - s2 - t2) (5b) hl 2 hminl (6a> h2 * hmin2 <6b) 25 m> m. (7) - min where the dimension m is shown in Figure 2b and the value m. is a predetermined value of this dimension ( programmed) minimum value.

The arrangement of the electronics unit 100 in which these calculation and comparison operations are performed is shown in the diagram of Fig. 6. For the sake of clarity, only Fig. 5 shows the signal processing of the left sensor 28 and Fig. 5 shows the adjustment of the left reduction plate 11. The same scheme naturally applies to the sensor 27 and the reduction plate 12.

A signal corresponding to the value (Fig. 3) is fed to a processor 101, from which a signal representing the value u ^ is obtained, which is the thickness of the board to be taken at a given minimum width of i4 69977 - A switch 101a is fed to a first comparator 102. the value of the board thickness U £ (the saw blade insertion-5 program is not a computer program, it indicates the relative position of the saw blades in the saw section 40). From the comparator 102, a signal e corresponding to the difference between u1 and U2 = n is supplied to the derivative 103 (e = u1 - U2). The signal e is applied in parallel to the second comparator 104 and its de-10 derivative e is applied to the third comparator 105. Depending on the obtained comparison result, this is applied from both comparators 104, 105 to either AND gate 106 or OR gate 107. AND gate 106 is further supplied with signal v. The outputs 106, 107 are connected to the transfer means 31 of the reduction plate 15 (Fig. 5).

The second comparator 104 thus determines whether e> 0, and when this is the case, the signal goes to the AND gate 106. The derivative e of the signal e indicates whether it does not increase or decrease, which is indicated by + and - next to the first-20 comparator 102 . If e> 0, e increases and the signal goes to AND gate 106, otherwise to OR gate 107. A comparison is made in the third comparator 105. When both e S 0 and e 2 0 and AND gate 106 have a signal at both respective inputs, as in the 25 third intake, the reduction plate 11 moves outward.

Said third intake is connected to a fourth reference member 108, which determines whether the length of any additional outer board is equal to or exceeds a specified minimum length (m>. M.). When this is the case, the sig-30 outputs to the third input of the AND gate 106. The value of m is determined in the subtraction unit 110, where the previously mentioned calculation operation (2) is performed. If desired, the electronic unit 100 may further be provided with a deceleration unit 109 after the three-way AND gate 106.

Since, in general, no special signal is required to keep the reduction plate 11 in a constant position, the OR gate 107 and its connection to the transfer means 31 can also be completely dispensed with.

is 69 9 7 7

The signal processing of the position sensor 27 for adjusting the reduction plate 12 naturally takes place in a corresponding manner. The unit 100 can also be more simply constructed, e.g. an algorithm which takes into account the distance 5 from the base end 10r of the log can be used to select the appropriate thickness and width of the board 16, 17 to be taken by the reduction plate 11, 12 and the outer saw blade 14 ', 15'. between.

It is obvious that the invention can also be used 10 in a reduction sawing device with only two saw blades, in which it is necessary to select only the supply of the middle piece 22 and possibly one or two outer boards 20, 21 of smaller length.

Depending on the length and conicity of the log, stepping out one or both of the reduction plates may be repeated one or more times.

In contrast to all known methods, inadequate additional side boards cannot be produced in accordance with the present invention, so that their removal and sulfur shredding in a separate harvester is eliminated. An even better yield of raw material is further achieved because the extra sideboard is made as soon as possible on at least one side of the log.

Claims (9)

69977 Claims: A method for machining logs (10) having a diameter increasing towards the base end (10r) and a narrower top end (10i) fed forward through a woodworking apparatus comprising a common center line (CL) along a plane reduction section (50) with two position weather an axially displaceable reduction plate (11, 12) by means of its pusher (31, 32), and a saw part (40) with at least one saw blade (14, 15, 18, 19) at least one board (16, 17) adjustable in its lateral positions. 20, 21) on both sides of the reduced log (10a), and in which the width of the log (x1 + x2) is measured before feeding the log into the reduction section and the distance between the reduction plates is increased depending on the measurement result during processing of the log for higher board yield and lower chip waste. that before feeding the log to the reducing part (50), both longitudinal contours of the log and their distance from the reference line 20 are measured and fed to an electronic calculator; to the unit (100) that during the forward feeding of the log through the apparatus, the longitudinal position of the log is continuously measured or counted and fed to said landing unit previously fed a minimum board thickness of 25 including the width of the saw gap and a minimum board width and width (hmin) and the log length (1) and providing control signals for lateral position adjustment of the reduction plates, and the counting unit determines when the log longitudinal-30 line on one side has moved away from the centerline of the hardware mm ^ n) and whether the additional sideboard would also have a programmed minimum pin-35 nan width (h. ) and whether the additional side board would also have a programmed minimum surface width (hm ^ n) <whereby in the present case a control signal is produced to , which corresponds to a predetermined thickness value of 5 boards and the width of the saw gap. A method according to claim 1, characterized in that the longitudinal contours of the log are felt at at least two different distances in front of the reduction part. Method according to Claim 1 or 2, characterized in that the outward stepping of the reduction plate is effected by a certain deceleration. Method according to one or more of the preceding claims, characterized in that the outermost saw blade (14 ', 15') in the saw section 15 is placed in its frame so as to tightly sweep past the passing flat surface previously provided in the reduction section, so that this the surface acquires approximately the same structure as the sawn surface also in the part from which the sideboard with more than 20 volumes has not been separated. Apparatus for machining logs according to one or more of the preceding claims, the apparatus comprising a woodworking apparatus having a common centering section (50) along the common centerline (CL) and two axially displaceable reduction plates (11, 12) by means of its positioning members (31, 32). ) and a saw part (40) with at least two saw blades (14, 15, 18, 19) adjustable in their lateral positions, for feeding the logs of the conveying device (13) through the machining equipment, the measuring device (27, 28, 27 ', 28') (10) for sensing the longitudinal contours and their position relative to the reference line, means (13a, 38, 39) for sensing the feed forward position of the log and for generating control signals of the electronic landing unit (100) to the position control means, characterized in that the electronic landing unit (100) is adapted to generate a control signal 12) stepping out every time 18,69977 is programmed and in on the basis of the information provided, it can be concluded that this allows an acceptable additional side board to be obtained from one of the two sides of the log. Device according to Claim 5, characterized in that the saw blade positioning means (34-37) of the saw section are connected via wires (d 1) to an electronic unit for automatically entering the saw blade setting program of the saw section here. Device according to Claims 5 and 6, characterized in that the sensing device for the longitudinal contours of the log is arranged in the immediate vicinity of the woodworking equipment. Device according to one or more of Claims 5 to 7, characterized in that the positioning means are double-acting hydraulic cylinder piston devices. Device according to one or more of Claims 5 to 8, characterized in that the electronics unit comprises a processor (101) to which a first reference element (102) is connected, to the output of which a parallel derivation unit (103) and a second reference element (104) are connected. and that a third comparator (105) is connected to the output of the derivative unit and that one output of the second comparator and one output of the third comparator are connected to an AND gate 25 (106), the output of which is in turn connected to said position control means. 19 69977