WO2006060855A1

WO2006060855A1 - Material handling for radial timber sawing

Info

Publication number: WO2006060855A1
Application number: PCT/AU2005/001842
Authority: WO
Inventors: Andrew Karl Knorr
Original assignee: Radial Corporation Limited
Priority date: 2004-12-09
Filing date: 2005-12-06
Publication date: 2006-06-15
Also published as: ZA200705564B; BRPI0517162A; RU2007126523A; WO2006060865A1; EP1827780A4; BRPI0517163A; CN101115598A; EP1827780A1; RU2007126522A; CA2633079A1; CN101115597A; CN101115598B

Abstract

A process and associated devices to enable efficient processing of radial wedge sectors of timber by the removal of the necessity for manual handling of the wedge sectors and the provision of a system of mechanical handling of wedge sectors to provide aligned wedge sectors for further processing.

Description

Material Handling far Radial Timber Sawing.

The present invention has for its object a process, and associated devices, for the reduction or elimination of the manual handling of wedge sectors of timber. The process provides for the mechanization of the handling and control of wedge sectors and wedge sector production.

Background to the Invention

It is a general object of wood processors to reduce wastage during the sawing of wood products from logs and to improve the quality of sawn timber or lumber produced from those logs. With these improvements it is also a desired objective to reduce the cost of production and to improve the safe working conditions of personnel involved in the production process.

One process that appears to offer the promise of reduced wastage and an improvement in product quality, and which has been the subject of a number of patent applications is the method of radial sawing in which logs are sawn to, or through, a chosen centre to produce longitudinally extending wedge sectors of timber with two radial faces. Despite the benefits detailed in these patent applications the radial method has not generally been adopted by the timber industry. This level of adoption could be caused by the lack of a process to avoid the manual handling of the wedge sectors.

While a number of inventive methods are given for cutting wedge sectors and the subsequent use of the wedge sectors, no processes or methods or devices have been devised or developed for the mechanical handling or alignment of wedge sectors. This development is critical for the safe, efficient and high speed production, and further processing, of radial wedge sectors.

Hasenwinkle (US Patent No.US4, 117,755) Seaman (US 4,068,695) and Knorr (US Patent No. 6,032,708) like others, deal with the cutting and use of radial wedge sectors but do not allow for the controlled mechanical alignment of wedge sectors to facilitate wedge sector processing. Hasenwinkle and Seaman allow for the uncontrolled release of cut or separated wedge sectors and the transfer of unaligned wedges for further processing with an assumption that the necessary alignment for further processing is carried out by manual handling means. This is normal to the industry when mechanical means do not exist. Knorr allows for the controlled release of wedge sectors but does not allow for or provide for a process to align the wedges prior to further processing. Description of the Current Invention

The current invention has for its objective the alignment and control of radial wedge sectors by mechanical or πon manual means to facilitate the production of sawn timber sections from logs.

The basic embodiment σf the invention is the application of mechanical pressure to a selected part or selected parts of a wedge sector to cause the wedge sector to move so that the plane that divides the two radial faces of consecutively processed wedge sectors are basically parallel prior to or during the further processing. (For the purpose of this invention the reference to further processing includes packing or preparation for transport)

Radial wedge sectors have two radial faces which meet (or the extensions of which meet) approximate to the chosen cutting centre of the log and are produced by either:

(1) sawing to (or close to) a chosen centre of a log a number of times with the log being rotated between cuts to produce elongated wedges of timber with a required angle between the two radial faces formed by the saw cuts on

(2) sawing a log through a chosen centre so that the log is cut into two portions which are then separated and further processed to produce radial wedge sectors.

As part of the process of wedge production for processing logs that have growth stresses (which cause logs to distort during sawing), the two halves of the log as it is divided may be restrained or held to contain or divide the growth stresses as evenly as possible into each of the sectors of the log. This holding process to control growth stress distortion could also be applied to the further sawing of the log halves to wedges. This log holding method can also be used to facilitate the sawing of logs without growth stresses by holding and controlling movement during production phases.

In particular embodiments of the invention wedges are further processed by cutting basically parallel to a tangent to the growth rings with the aim of producing backsawn sections of timber and in other embodiments wedge sectors are further processed by cutting basically quarter sawn sections of timber by making alternate saw cuts parallel to alternate radial faces or by producing basically quarter sawn sections by making multiple cuts on or parallel to the plane that bisects the two radial faces or by cutting further wedge sectors by basically dividing the wedges into further wedge sectors by cutting on one or more planes that divide the radial faces. Radial wedge sectors of timber have- advantages for transfer and handling in that the radial faces present economical and accurate alignment, transfer, cutting and processing references. Aligned wedges will either rest on or be supported on one radial face when being transferred on a bed or rest or be supported on two radial faces when in a v type trough. When this happens corresponding faces of consecutive wedge sectors are basically parallel.

For practical transfer and processing, radial wedges must have the radial faces consistently aligned so that consecutive wedges have both- faces basically parallel and so that the plane that divides the two radial faces are basically parallel in the aligned wedges.

In the radial cutting process while the wedges are in the log the adjoining radial faces are parallel but the planes that bisect the radial face of each wedge are not parallel and are basically radial planes pointing to the cutting centre of the tree. The object of this embodiment of the invention is to provide for the practical movement of the alignment of the wedge bisecting planes from meeting at the log centre to being basically parallel to each other or so the planes are basically at a similar angle to another plane and so that the apex of the radial faces basically point in the same direction. In relation to references to the dividing plane and radial faces being "parallel" allowance must be made for the fact that wedges may spring. due to the effect of stresses in the log, or saw variations causing inaccuracy. Also if a wedge sector were out of longitudinal alignment the dividing planes would not be exactly parallel. These effects are excluded for references to "parallel" and "similar angte" and the like.

Aligned wedges could then be fed to the processing machines on the same plane or tipped or manoeuvred into a v type trough. White some species will exhibit spring from high growth stress a v trough driven by powered rollers, belts or pushing devices will provide or can be designed to provide transfer and referencing ability for all rates of spring or bow caused by growth stress.

If wedge sectors are to be aligned basically side' by side on chains or rollers for transverse or lateral movement in relation to the length of the wedges to facilitate ease of processing, it is desirable that (he apexes of the radial faces point in the direction of travel.

Prior art specifications allows for release of all wedge sectors at the one time. With simultaneous release, log stress and or/ gravity effects can cause a large degree of misalignment. A basic method for simultaneous release would be to drop the wedges into a trough or onto chains for side transfer. Some wedges would be aligned in the required direction, some opposite and some would be on top of each other and some on the round back with the plane basically vertical.

In one embodiment the invention the wedges would be dropped onto a means to move the wedge sectors laterally in relation to the cutting position of the log or laterally in relation to the longitudinal axis of the wedge sectors. These lateral movement beds could include slides, rollers, belts or chains. In this embodiment of the invention the beds, or sections of the bed. are fitted with remotely activated stops and flipping arms that apply pressure to selected parts of the wedges so that wedges can be separated, aligned, or flipped or turned over to result in the required alignment of radial faces and dividing planes.

An alternative embodiment involves the selection of wedges that are not aligned in the required manner and the rotation of the selected wedges around a vertical axis so that the wedges are aligned in the required manner. This could involve the lifting and rotation of the wedge sector or the rotation of the wedge sector on a turntable type device.

Control of the two prior embodiments could be by an operator visually deciding on the required actions to align the wedges or by camera or scanning means to control the mechanical operations. Knorr"s sawing device allows for the controlled release or the control of the position and time of release of the sawn wedge. Wedge sectors are sawn along radial lines with the holding aspect of the sawing device allowing travel of the saw between the holding pins to allow complete cutting of the wedge along the length of the log. Control of wedges individually released by KnOrT¹S holding arms or pins requires the controlled movement either by gravity or by applying or using pressure to move the wedge away from the log centre.

A preferred embodiment is to release and remove one wedge and then rotate the log so that the same position and device is used to remove the next wedge. This provides for minimizing turning and the complexity of machines or mechanisms required. In one embodiment of this aspect of the invention the cut log is rotated so that a cut wedge is released with one face at an angle so that gravity causes pressure on that face and the adjoining radial face so that the wedge sector slWeε on the adjoining radial face in a controlled manner away from ihe cutting centre. A slide device can be aligned with a wedge sector face basically parallel to the radial face or at a suitable angle may be positioned to support the sliding wedge adjacent to the outside of the radial wedge to facilitate the controlled slide of the wedge to the required position. The sawing device can rotate so that consecutive wedges slide down adjoining faces as the wedges are released The previous (or another) sliding device can be positioned in the gap caused by removal of the first wedge to facilitate the sliding of the last wedge to be released as there is no adjoining wedge sector remaining for the released wedge to be slid on. Conversely the sliding device could be moved into the sap created by removal of the first wedge with all the wedges after the first removed by sliding down the sliding device. Wedges could be individually released from the Knorr sawing device to facilitate the orderly turning of wedges by stops and or flipping arms. Vacuum devices could hold the sector by lowering pressure and using atmospheric pressure on the wedges to grip and move the wedge sectors away from the cutting centre and hold it until it is placed in the required position.

Mechanical devices could hold the sector on the outside or natural face or other practical location to lift or pull the wedge sectors from the log and hold it until it is placed in the required position.

In a preferred embodiment a removal device is mounted on each of the trolleys or support devices that have the Knorr (US Patent No. 6,032,708) log and sector sawing devices mounted on them. The removal device comprises holding arms that grip or clamp each end of the sector to be released by compressive means, that then can travel away from the centre of the cut log with the released sector to a distance that clears the remaining sectors of the log, and that rotates and then releases or deposits the wedge sector in the required position by moving the holding arms away from the end of the wedge sector. The log is rotated so that the next wedge for removal is in the same position that the removed one was in. The arms rotate back to the moving position and then move back into gripping or clamping position. Compressive force is applied to grip the next wedge sector, the Knorr sawing device releases the sector portion, the holding arms move the sector away form the log and the process is repeated until all sectors of the log are downloaded or uploaded. In the cutting of pine or togs with no or ignorable growth stresses wedges could be removed from the log and sector holders as the logs were cut Alternatively, in logs like this, logs could be held at one point and the clamping device could hold the section of the log as it is cut and remove the wedge sector when it has been sawn and separated from the log. , Wedges can be gripped or clamped in such a way as to deposit or release the wedges into a v type roller trough or v holder or fiat or angled transfer bed. Movement of the wedge sectors can be parallel to the longitudinal axis of the wedges or laterally in relation to the axis or a combination of lateral and longitudinal or transverse movement. The above device could also be fitted with a pivot at the clamping or pressure head to allow the movement of wedges away form the log without the lateral movement of the removal device or to facilitate the positioning of the wedges for further transfer or processing.

In the above preferred embodiment the same device that is used to remove the wedges can be used to position the log into the Knorr sawing device prior to cutting to wedges. This aspect of the embodiment and other aspects of the invention are described and detailed in the following description and the associated accompanying drawings.

Description of the Drawings Figure 1 shows a drawing from Haseπwiπkle US 4,117,755 showing the known state of the art with unaligned wedges being transported for further processing. Figure 2 shows a log radial cutting pattern with a selected or chosen cutting centre which may or may not be the geometric centre of the log. The wedge cutting pattern could comprise any number of sectors with six sectors being used as an example only. For the purposes of this specification the cutting centre may refer to the position in the log before during or after it is cut or before during or after the wedges are separated or removed from the cutting position or sawing device. Cuts may be made to or through or approximate to the centre. In the practice of radial sawing it can be beneficial to leave a small centre in the log at the saw cut junction so that the cutting centre may be timber with the actual saw cuts not quite reaching cutting centre.

Figure 3 shows a wedge sector with two radial faces (2) and a dotted line (3) that represents the plane that divides the two radial faces. (4) indicates the natural or bark edge of the wedge sector which in practice may be in its natural state or may be fully or partially cut or machined. The two radial faces meet at an apex which in practice may or may not exist due to the apex of the wedge sector being broken off or in the case of a defective or partially decayed log which is hollow. In these cases it is treated as a theoretical apex.

Figure 4 shows timber sections with the growth ring alignment in (5) indicating a quarter sawn board with the curved growth rings basically at right angles to lhe broad face and (6) indicating a backsawn board with growth rings basically tangential to the broad face. Variations on the angle of the growth rings in relation to the broad face occur but may still fall within the industry definition of backsawn and quarter sawn. Figure 5 shows a wedge sector with dotted lines showing a cutting pattern to produce basically quarter sawn sections of timber.

Figure 6 shows an alternate quarter sawing pattern where sections are alternatively cut from alternate sides of the wedge sector.

Figure 7 shows a wedge sector with dotted Ifπes showing a cutting pattern to produce basically quarter sawn sections of timber. Figure 8 shows a wedge sector with dotted lines to indicate where wedge sectors could be cut along radial planes to subdivide wedge sector into further wedge sectors. Figure 9 shows a log divided into two sections (6) as part of a process of wedge sector production and with the division made along cut line (7). The cut would be made through the chosen cutting centre. Figure 10 shows a partially cut log from the top at a right angle to the cutting plane (12). If the log has growth stress the cut sections of the log will separate as shown at (14). If holding devices are used such as indicated by lines (9) then the separation can be controlled and the stress relieved evenly into each section. The control of separation basically keeps the cutting plane that divides the cut faces straight. If the log is only held one side and there are growth stresses the cutting plane curves as the cut progresses making unevenly balanced sections and putting side pressure on the cutting device as the cut progresses. The aim erf restraining both sectors during cutting is to produce, when the sections are released, two sections that are both equally straight or both equally curved by the growth stresses in the log. The dotted line (12) can also represent the longitudinal axis of the log which has a length and in the same way the wedge sectors have a longitudinal axis that relates to the wedge sectors length. Figure 11 shows an end section view and the cut line with (9) indicating holding points. Figure 12 shows how a log can be held with dual holding means (9) to allow cutting at cut line (7) and released to, or rotated in a controlled manner to, a new cutting position as shown by Figure 13. The sawing of wedges this way can control growth stresses as previously described.

Figure 14 shows an indicative movement path for the movement of a wedge sector away from the cutting centre of the log and the turning of the sector to a required alignment. Figure 15 shows indicative movement of a wedge sector by the release and sliding of the sector down its radial face and the plane of an adjoining radial face. (16) indicates a slide device which aligns with the wedge sector face to facilitate the controlled sliding with the lower arrow showing where the device could be moved . in bo support wedge sectors when there is not an adjoining wedge sector to support- Figure 16 shows the path a wedge sector could take when a removal device with a pivoting holding head is used to remove the head. If the pivoting head is powered the wedge sector could be aligned in any required manner by rotating the pivot head to the required position. Figure 17 shows random aligned wedge sectors that need to be aligned to facilitate further processing.

Figure 18 shows wedges being transferred in the direction of the arrow (20) segregated by stops indicated by (17) which can flip up in the plane parallel to the longitudinal axis of the wedges to stop the movement and to separate the wedges as required. These stop devices can be repeated as often as is required to align and separate the wedge sectors to facilitate their alignment. (19) indicates flipping devices to flip or turn or rotate the wedge sectors around their longitudinal axis to gain the required alignment. Wedge sectors would be allowed to travel past the flipper pivot to the best position to facilitate the turning of the wedge sectors when the pressure is applied in the most appropriate position. The transfer means may be stoppable to facilitate the application of pressure at the correct point. Flipping devices can be repeated as often as is required to align the wedge sectors.

Figure 20 shows wedge sectors aligned so that the apex of the radial face and the radial faces are all facing basically in the same direction and the plane that bisects the radial faces are basically parallel and the plane that bisects the radial faces is at a similar angle to the transfer plane as an adjoining wedge sector as shown by lines (21) and their associated angle. For the purpose of this diagram the term basically is used as, if some wedges were longitudinally misaligned, the said faces would not be completely parallel and similarly the effect of distortion from growth stresses could have similar effect. The intent of this definition is to define that the wedge sectors are facing in the same general direction as could be defined by saying the apexes of the radial faces are all pointing in the same direction. The same definition as referred to by Figure 20 could be applied to the alignment of wedge sectors one after the other along or parallel to the longitudinal axis of the wedge sectors. Figure 21 shows an aspect of a preferred embodiment of the invention in which a Knorr sawing device is mounted adjacent to a wedge sector removal device. The removal device would be mounted on the same platform as the Khoπr sawing device and would adjust to differing log lengths along with the sawing device. Removal devices work in pairs to hold and remove wedge sectors by applying pressure at each end of the wedge sector. (22) shows the pins that hold the log and each wedge sector as it is cut and after it is cut. The pins can move parallel to the longitudinal axis of the log and have independently controllable means to release individual wedge sectors (23) as required. An arm (24), which can have suitable gripping attachments, pivots around an axis (25) and applies pressure to the end of the wedge sector to grip and hold the wedge sector. The sawing device releases the wedge sector to the wedge sector removal device. The pivot has means to travel sideways in relation to the longitudinal axis of the log to move the wedge away from the cutting centre of the log so that it can clear adjacent wedges as is shown by the shifted position of the pivot point at (28) in Figure 22. The lag rotates as indicated by arrow (27) to a new wedge sector release position as shown by wedge (29) in Figure 23. The arm rotates to position the held wedge sector onto a transfer bed so that each wedge sector is aligned in the required direction as indicated by the arrow and wedge sector (30). The pressure is removed from the end of the wedge sectors to release the wedge sectors. The arrow (30) indicates a direction of travel for the further processing of wedges, in a similar way the wedge sectors could be inserted or guided directly into a wedge shaped roller or holding trough or referencing device. This sequence of drawings show the wedges being held at a particular angle. Wedges can be rotated and then held or removed at any suitable angle to facilitate the release of the wedge sectors in Ihe required position. Figure 24 shows the end section of a log (32) which can be clamped by the wedge sector removal device and rotated into the cutting position to be held by the pins of the Knorr sawing device as shown by (33). In the preferred embodiment of this aspect of the invention the log would be pre-aligned at its damping position and rotated in its correct position for sawing in the sawing device. If the log has knots or defects in certain places the sawing device could be rotated before the log is gripped so that when the log and sawing device are rotated back into the cutting position and sawn the defects are contained in certain or a minimum number of wedge sectors.

Figure 26 shows a variation on the previous preferred embodiment where two Knorr sawing devices and wedge removal devices are basically mirrored around a station for clamping pre aligned logs (35). Logs can be pre-aligned at a remote station and could be delivered to the clamping station by a rail and holding device along or parallel to the mirror plane. Dotted arm (36) shows a iog damping position. Clamp arm (37) transfers logs to sawing device (38) and clamp arm (39) transfers logs to sawing device (40). The damp arms have means to move laterally with arm (37) moveable a greater distance as it is required to move away from the cutting device to clear the remaining wedge sectors and then moves back towards the log so the wedge misses the transfer device (41) as it is rotated and moves away from the log again to the wedge deposit position as shown by dotted arm and wedge sector (42). This arm is rotated in a direction opposite to the other arm (39) to achieve the alignment of the wedge sectors which is the abject of the current invention. Sawing devices are rotated to a selected position and the oriented wedge sector is clamped in that position. This rotation effects the angle that the wedge sectors is deposited to the transfer bed. In the shown embodiment the wedge sectors have been rotated 15 degrees from the cutting position to facilitate rotation and deposit of the wedge sector.

In certain embodiments of the invention the drive device for the saw blade that cuts the log and travels between the holding pins of the Knorr sawing device can be mounted offset to the log cutting position to provide clearance and room for the log insertion and wedge removal, In the mirrored embodiment the saw driving mechanisms would be positioned furthest apart at the extremes of the mirrored setup.

The current embodiment could include a number of objectives or operations to achieve efficient further processing of wedge sectors. The main objective of the mirror type setup is Io achieve a high wedge processing rate. Further processing of wedges can be at a quick rate when taking place with a lineal type set up where the wedge sectors are processed progressively or simultaneously. In certain setups the reciprocating nature of the Knorr saw device and the time the saw is not operating when logs are being loaded could mean the radial cutting is the slowest part of the operation. With the mirrored saw, while one log was being cut the other log would be being removed from the saw device as wedges and then a new log loaded. If the wedge sectors have data recorded about them at the sawing device the wedge sectors can be transferred in an orderly and recorded manner so that the data can be used to facilitate further processing. This mirror process can provide for higher rates of wedge sector production without the need for duplicating log supply and alignment infrastructure and also provides for the orderly delivery of cut wedges to a single further processing line.

Claims

The claims that define the invention are as follows:

Claim 1. A process in which wedge sectors of timber, which are produced by cutting to, or through, a chosen cutting centre of a log to form a wedge sector of timber with two radial faces, are, prior to further processing, aligned by the application of non manual pressure to a selected part or selected parts of the wedge sector so as to cause the apex of the radial faces of consecutive wedge sectors to point in the same genera! direction.

Claim 2. A process according to Claim 1in which the wedge sectors are aligned by either

(a) Holding and moving each wedge sector as it is separated by sawing from an adjacent wedge or released from a device that was holding a sawn wedge, or

(b) Releasing or separating the sawn wedge sectors and then applying mechanical pressure to selected parts of the wedge sectors that are not in the required alignment, or:

(C) Sliding a wedge sector along a plane of an adjacent radial face after it is separated by sawing from an adjacent wedge or released from a device that was holding the sawn wedge, on

(d) Releasing or separating the sawn wedge sectors and then selecting wedges that are not in the required alignment and mechanically rotating the non aligned wedge sectors around a vertical axis.

Claim 3. A process according to Claim 1 in which as part of the process of cutting a log to, or approximate to, the chosen cutting centre to produce a sawn wedge sector, both the wedge and the timber section that the wedge was cut from is he!d or supported.

Claim 4. A process according to claim 1 in which as part of the process of producing a wedge a log is cut through the middle or cutting centre to divide the log into two sections with both sections of timber being held or supported.

Claim 5. A process according to claim 4 in which the log is held so that the two log sectors are held before, during and after separation.

Claim 6. A process according to Claim 4 in which the log is held so that growth stresses that may be contained in the log are divided as evenly and consistently as possible into each log sector.

Claim 7. A process according to Claim 1 in which sawn wedge sectors are clamped on the ends and the clamped sawn wedges sectors are moved away from the cutting centre, Claim 8. A process according to Claim 7 in which the clamped wedge sectors are moved away from the cutting centre and rotated.

Claim 9. A process according to Claim 7 in which a sawn wedge sector, which has been held as part of the sawing process, is released to the clamping device. Claim 10. A process according to Claim 7 in which the clamping device is used to position an uncut log in the cutting device.

, Claim 11. A process according to Claim 7 in which the log sawing mechanism rotates to the required position so that the clamping device can clamp the end of the sawn wedge sector at the required position.

Claim 12. A process according to Claim 7 in which a portion of a log which is to be cut to a wedge sector and which is not held by other means is clamped on the ends and moved from the cutting position by the clamping device once the wedge sector is separated by sawing.

Claim 13. A device according to Claim 1 which incorporates clamping devices to contact and hold the end of a sawn wedge sector, or section of a log that is to be sawn to a wedge sector, and means to move the wedge sectors once the sector is released or sepa rated by sawing.

Claim 14. A device according to Claim 13 which has the clamping devices mounted on the same platform as the log holding devices.

Claim 15. A device according to Claim 13 which has the clamping devices mounted on means to enable the movement of the clamping devices towards and away from the log cutting device.

Claim 16. A device according to Claim 13 which incorporates a pivoting arm with clamping means that can move to apply and release pressure on the end of a log or wedge sector so that the clamping means can contact and hold the log or sector and move and /or rotate the log or sector and release the log or sector as required. Claim 17. A device according to Claim 13 that incorporates a pivot point at or close to the clamping point so that the log sector or wedge sector can be rotated independently of the pivoting arm.

Claim 18. A process according to Claim 16 in which a log is held in a position by an independent Jog holding device and in which a wedge sector clamping device clamps the log and moves the log to the cutting position and at the end of the necessary cutting stage removes the sawn wedge sectors from the cutting device and deposits the sawn wedge sectors in an aligned position. Claim 19. A process according to Claim 16 in which a log is held in a position by an independent log holding device and in which a wedge sector clamping device clamps the log and moves the log to the cutting position and at the end of the necessary cutting stage removes the sawn wedge sectors from the cutting device and deposits the sawn wedge sectors in an aligned position and in which a further wedge sector clamping device mounted on the other side of the independent log holding device can also clamp a log from the same log position and move the log to an alternate cutting position and cutting device and at the end of the necessary cutting stage remove the sawn wedge sectors from the cutting device and deposit the sawn wedge sectors in an aligned position so that two cutting devices can produce wedge sectors and deposit aligned wedges- Claim ZD. A device according to Claim 19.

Claim 21. A device according to Claim 1 which rotates a selected wedge sector around a vertical axis.

Claim 22. A device according to Claim 1 which incorporates a slide to support a wedge sector and which aligns with a radial wedge sector face to facilitate the sliding of the wedge sector.

Claim 23. A process according to Claim 16 in which the log sawing device rotates to a required position to take hold of the log and then rotates back to a cutting position so the log is held in a position for cutting that contains the defects which may occur in the log to a minimum number of wedges.

Claim 24. A device according to Claim 1 in which stopping and flipping devices apply pressure to selected parts of selected wedges to cause the wedge sectors to rotate around their longitudinal axis. Claim 25. Timber sections produced according to Claim 1