ARRANGEMENT AT BINS

Abstract: A sawmill bin arrangement in which a given number of bins are placed sequentially one after the other and which are adapted to receive sorted wood pieces which are transported by means of a transporter which moves over the bins, wherein the wood pieces are released from the transporter into predetermined bins, wherein each bin includes two defining walls which limit the width of the bin, wherein the defining walls are positioned at right angles to the transporting direction of the transporter, and further include a bottom, wherein the bottom of each bin can be moved from an upper position to a lower position and is constructed to empty wood pieces that have been collected in respective bins onto an underlying transporter for transportation to further treatment. The invention is characterized in that one or more of said bins (1, 2; 44-46) is/are provided between the upper (9') and the lower (10') position of said bottom (9, 10; 32-33) with a plurality of mutually spaced arms (18, 19; 25-28) which are located along the length of the bin and which can be swung from an inactive position, in which they are located outside the space present between said defining walls (6-8; 29-31), to an active position in which they extend across said space and therewith function, in their active position, to support the wood pieces that have been dropped down into the bin (1, 2; 44-46).

Description: ARRANGEXENT AT BINS The present invention relates to a sawmill bin arrangement. After timber has been divided into planks and boards, the wood is then roughly sorted. This is effected by transporting the wood on a transport table where wood sorting personnel, or a measuring appliance, determines how much of the planks and boards shall be cut away in order to remove faults in the top end and the root end of the timber. The dimensions are measured and the quality of the wood is also noted, to some extent. The wood is then packaged and thereafter dried in a wood dryer. The dried wood is dry-sorted in a trimming mill, wherein extent to which the wood shall be cut at the root end and the top end is determined by sorters, or by a measuring appliance, who/which also determine the quality of the wood. After all sorting criteria have been determined and after having cut the wood as required, i.e. after the wood has passed along the transport table and along a trimming table in the trimming mill respectively, the pieces of wood are placed one by one in different mutually sequential bins. The bin into which a given piece of wood is placed will depend on the cross-sectional dimensions of the wood, its quality and in certain cases its length. This means that a large number of bins must be available, this number reaching from 30 to 50 bins in both the rough-sorting and the dry-sorting departments. The wood is thus collected in bins which are emptied onto an underlying conveyor for further transportation. Unseasoned wood, or green wood, is transported to a flat stacker in which the planks or boards are stacked to form a package, which is then transported to the wood dryer. Dry wood is transported to a packaging machine to form a wood package which is ready for delivery. Because of the different packages to be formed, the bins are to be emptied when they contain a predetermined number of wood pieces. The length of time taken to fill a bin will vary as a result of the different combinations of dimensions, lengths and qualities that occur. However, the number of bins must be dimensioned so that there will always be a sufficient number of bins available. It is less usual, however, for all bins to be used simultaneously. Many bins are required, particularly when a change is made to wood pieces that have a different cross-sectional dimension or which are of a different kind of wood, since a number of bins will contain the earlier wood sort. It is necessary to empty these bins before being able to feed wood pieces of the new sort thereto. This often means in practice that trimming of the new sort cannot begin until all, or essentially all, bins have been emptied. The cost of a bin is relatively high. This cost is not only entailed by a mechanical construction but also by the fact that a building structure must be extended to accommodate the addition of more bins. It is therefore desirable to keep down the number of bins required. Furthermore, when expanding an existing sawmill, and, for instance, increasing its capacity or in which it is desired to handle additional sorts of wood, it is desirable to avoid increasing the number of bins without reaching the situation in which the number of bins available when the mill is operating is too small. The present invention solves these problems and enables the number of necessary bins to be reduced. The invention also enables a reduction in the times taken to switch from one wood sort to another. The present invention thus relates to a sawmill bin arrangement in which a given number of bins are placed sequentially one after the other and which are adapted to receive sorted wood pieces which are transported by means of a transporter which moves over the bins, wherein the wood pieces are released from the transporter into predetermined bins, where each bin includes two defining walls which limit the width of the bin, wherein the defining walls are positioned at right angles to the transporting direction of the transporter, and further include a bottom, wherein the bottom of each bin can be moved from an upper position to a lower position and is constructed to empty wood pieces that have been collected in respective bins onto an underlying transporter for transportation to further treatment, and wherein the arrangement is characterized in that one or more of said bins is/are provided between the upper and the lower position of said bottom with a plurality of mutually spaced arms which are located along the length of the bin and which can be swung from an inactive position, in which they are located outside the space present between said defining walls, to an active position in which they extend across said space and therewith function, in their active position, to support the wood pieces that have been dropped down into the bin. The invention will now be described in more detail, partly with reference to exemplifying embodiments thereof shown in the accompanying drawings, in which - Figure 1 is a side view of the first two bins of a bin line, in which a first embodiment of the invention is applied; - Figure 2 is a view seen from the right of Figure 1; and - Figure 3 shows the first three bins in a bin line, in which a second embodiment of the invention is applied. Figure 1 illustrates a sawmill bin arrangement in accordance with the invention. A given number of bins 1, 2, for instance from 20 to 40 bins, are placed one after the other and are adapted to receive sorted wood pieces transported by means of a transporter 3 which moves over the bins. The transporter 3 transports the wood pieces in the direction of the arrow 5 and drops the wood pieces into predetermined bins 1, 2. Each bin includes two defining walls 6, 7; 7, 8 which limit the width of the bin and which extend perpendicularly to the movement direction 5 of the transporter 3. The bins also include a respective bottom 9, 10 which can be moved from an upper position 9' to a lower position 10'. Each bin bottom is intended to empty the wood pieces that have collected in respective bins onto an underlying transporter 4 for transportation to further treatment. The wood pieces are emptied onto the underlying transporter 4 as a result of the bin bottom being moved to the aforesaid lower position 10', in which the bottom is located beneath the upper level 11 of the underlying transporter. Figure 2 is a schematic illustration of the arrangement shown in Figure 1 as seen from the right in said Figure. Each bin bottom consists in a plurality of mutually spaced carrier arms 12 which are supported by a beam 13 which can be moved upwards and downwards between the aforesaid upper and lower positions by means of a drive 14 which is attached to the two ends 16, 17 of the beam 13 through the medium of chains 15. The bottom of an empty bin is normally placed in the upper position 9'. As the wood pieces are fed down into the bin from the transporter 3, the bin bottom lowers so that the distance through which the wood pieces fall from the transporter onto the uppermost wood pieces in the bin will be short. This reduces the risk of damage to the wood pieces. Bins of the type hitherto described are very well known in the sawmill industry and are available in many different designs. The present invention is not restricted to any particular type of bin, but can be applied to all of the different types of bin occurrent in the sawmill industry. According to the invention, one or more of the aforesaid number of bins is/are provided between the upper and lower positions 9', 10' of a respective bottom 9, 10 with a number of mutually spaced arms 18, 19 which are positioned along the length of the bin. These arms can be swung in the vertical plane, from an inactive position 18' in which they are located outside the space present between said defining walls 6, 7; 7, 8 to an active position 19' in which they extend across said space and therewith function, in their active position, to support the wood pieces 20 that are released down into the bin. According to a first preferred embodiment of the invention, the pivot point 21, 22 about which the arms 18, 19 swing is located at one of said defining walls 6;7. The lengths of the arms are such that in their active positions 19' the arms will extend to opposing defining walls 7;8 and therewith support wood pieces 20 that have dropped down into the bin. Thus, when the arms 18, 19 are activated so as to swing from their inactive positions 18' to their active positions 19', those wood pieces that are thereafter released into the bin from the transporter 3 will land on the arms. This allows wood pieces to be released down into a bin which already contains wood pieces of another sort, these latter wood pieces being supported by the bin bottom 9, 10. When the wood pieces that rest on the bin bottom have been discharged to the underlying transporter 4, the bin bottom is moved up to a position immediately beneath the position of the arms 19, whereafter the arms take their inactive positions. This causes the wood pieces supported by the arms to fall down onto the bin bottom. Further wood pieces are thereafter released into the bin from the transporter 3, wherewith the bin bottom moves downwards so as to maintain the uppermost wood pieces in the bin at a generally constant level, as earlier mentioned. Figure 3 illustrates schematically a second preferred embodiment of the invention, which includes the arms 25, 26; 27, 28 at both defining walls 29, 30; 30, 31. The types of bin shown in Figure 3 are different to those earlier described although they operate in accordance with the same principles as those described with regard to the bins of the Figure 1 embodiment. The bins 44, 45, 46 have bottoms 32, 33, 34 which are moved between their respective upper and lower positions by means of chains 35 driven by an electric motor 36. The chains are firmly attached to a beam 37, in a manner corresponding to the beam 13 in Figure 2. The upper transporter in Figure 1 is indicated by means of the chain 38 in Figure 3. The underlying transporter is indicated by the chain line 39 in Figure 3. The arms 25-28 of this second embodiment are journalled in journal bearings 40 for carrying out their swinging movement at respective defining walls 28-31. According to this embodiment, the length of the arms is shorter than the distance between the defining walls 29-31. When in their active positions, the arms project out from respective defining walls so as to meet or mutually overlap at their free ends 41, 42 and function to support the wood pieces 43 that are released down into the bin. As shown in Figure 3, the arms are in an inactive position in the bin that is referenced 46. The arms 47, 48 are shown in broken lines. According to a further preferred embodiment of the invention, each set of arms on a defining wall 6; 7 is non-rotatably mounted on a journalled rod 23 which extends parallel with the defining wall and which can be pivoted by means of a power source 24 so as to move the arms 18 between their inactive and active positions. The power source is suitably a hydraulic piston-cylinder device. This embodiment applies correspondingly also to the aforesaid second embodiment of the invention. It is highly preferred, if not necessary, that the arms 18, 19 are located close to the upper position 9' of respective bin bottoms 9, 10. This embodiment also applies correspondingly to the aforesaid second embodiment of the invention. The invention therewith enables a reduction in the number of bins that are required in a given sawmill operation, since the invention enables a number of bins to be used temporarily as additional bins. This eliminates the drawbacks mentioned in the introduction. A number of embodiments have been described in the aforegoing. However, the invention can be modified in many ways that will be obvious to the person skilled in this art. For instance, each arm can be driven individually. Furthermore, the arms may have other configurations and may be placed further down in the bins than shown in the drawing. The number of arms may also be varied. In one modification, the arms can be swung in a horizontal plane instead of in a vertical plane. In this case, each arm is journalled at one end about a vertical pivot means on the same level as the journal bearing 22 in Figure 1. This journal bearing, and also each arm, can be let into a groove in the bin defining walls 6, 7, 8, so that when the arm is received in the groove, the inactive position of the arm, said arm will lie flush with the defining wall. When the arms are to be moved to their active positions, the arms are swung out around the journal bearing of each arm, in a horizontal plane until the arms extend between the bin defining walls. Those arms that are common to one bin may be moved between their inactive and active positions, and vice versa, by means of a horizontally extending pull rod to which each arm is pivotally connected close to said vertical pivot means. The pull rod can thus be moved reciprocatingly in its longitudinal direction. The pull rod may be driven by means of a hydraulic or pneumatic piston-cylinder device. Instead of providing a common manoeuvering means for all arms that belong to a given bin, the arms can be manoeuvered individually by means of hydraulic or pneumatic pistoncylinder devices, for instance. This also applies to the first-mentioned embodiments. As will be understood, the present invention can also be applied to wood bins of the kind which do not include a movable bottom. Such bins have an openable bottom which is normally placed at a level in the bin which corresponds to the position of the beam 50, see Figure 1. In the case of this application, the arms will preferably be placed at positions corresponding to those shown in Figure 1. The present invention shall not therefore be considered to be limited to the aforedescribed and illustrated embodiments, since modifications can be made within the scope of the following Claims.

Claims: CLAIMS 1. A sawmill bin arrangement in which a given number of bins are placed sequentially one after the other and which are adapted to receive sorted wood pieces which are transported by means of a transporter which moves over the bins, wherein the wood pieces are released from the transporter into predetermined bins, wherein each bin includes two defining walls which limit the width of the bin, wherein the defining walls are positioned at right angles to the transporting direction of the transporter, and further include a bottom, wherein the bottom of each bin can be moved from an upper position to a lower position and is constructed to empty wood pieces that have been collected in respective bins onto an underlying transporter for transportation to further treatment station, characterized in that one or more of said bins (1,2; 44-46) is/are provided between the upper (9') and the lower (10') position of said bottom (9,10; 32,33) with a plurality of mutually spaced arms (18, 19; 25-28) which are located along the length of the bin and which can be swung from an inactive position, in which they are located outside the space present between said defining walls (6-8; 29-31), to an active position in which they extend across said space and therewith function, in their active position, to support the wood pieces that have been dropped down into the bin (1,2; 44-46). 2. An arrangement according to Claim 1, characterized in that the journal points (21) about which the arms (18, 19) swing are located on one of the aforesaid defining walls (6; 7); and in that the length of the arms (18, 19) is such that when in their active positions the arms extend to the opposite defining wall (7; 8) so as to support the wood pieces that are released down into the bin (1, 2). 3. An arrangement according to Claim 1, characterized in that the arrangement includes arms (25-28) on both of the defining walls (29, 30; 30, 31), said arms (25-28) being journalled for pivotal movement on respective defining walls (29, 30; 30, 31); in that the length of the arms is shorter than the distance between the defining walls (29, 30; 30, 31); and in that the arms (25-28) in their active positions extend out from respective defining walls so as to meet or overlap one another at the free ends (41, 42) of said arms, so as to support the wood pieces that are released down into the bin. 4. An arrangement according to Claim 1, 2 or 3, characterized in that the arms (18, 19; 25-28) are located close to the upper position of respective bin (1, 2; 44, 45) bottoms (9, 10; 32, 33). 5. An arrangement according to Claim 1, 2, 3 or 4, characterized in that a set of arms (18, 19; 25-28) on a defining wall are non-rotatably mounted on a journalled rod (23) which extends horizontally and parallel to the defining wall and which can be rotated by means of a power source (24) such as to move the arms between their respective inactive and active positions by pivotal movement of the arms in a vertical plane.

Inventors: LARSSON STAFFAN, LARSSON, STAFFAN
Applicants: AHLSTROEM MACHINERY AB, LARSSON STAFFAN, LARSSON, STAFFAN
Application year: 1995
Main classification: B07C5
IPC codes: B07C5