| SE421453B | 1981-12-21 | |||
| SE425720B | 1982-11-01 | |||
| SE381334B | 1975-12-01 | |||
| SE380087B | 1975-10-27 | |||
| SE22973C1 | 1907-08-24 | |||
| SE313171B | 1969-08-04 | |||
| SE11032C1 | 1900-06-02 |
| 1. | p P 33 Ul tr O rt P P* 3 tr p Hi tr 3 • 3 ιQ P 3 0 φ rt Φ Ω φ d P O et tr 03 rt d > Φ tr rt 3. |
| 2. | P X Φ Cl tr rt P* φ P1 3 rt o φ φ Hi P Φ fl Hi | P* P d 03 rt 3 H P Φ 3 01 P 3 3 Pi P Ω tr rt rt 3 o P* 3 rt φ O 33 Φ Pi 3 Φ et o P* 3 03 S3 $3 Φ 3 Pi rt Hi P tr ¬ Φ 3 Φ rt O tr 01 Φ 03 tr *3 h Φ 01 tr 3 P TJ P* rt φ •»• 3 P o |t tr * rt Φ P* Hi 3" rt Φ er 3* Ω 3 H P* Φ P* Φ tr Φ rt P 3 ti *< P 3 o tr 3 3 tr H rt Hi Φ P rt tr* O P Φ 3 3 P Ω 33 3 er P. 03 Φ H ft P* d o 03 P Pi Φ rt et P P P o Ul. H tr d H 3 P t< P 3 Ω P* P Pi 03 > 33 P O N rt P* d trt 3 3 Φ 3 P* P 3 P Ω 3 TJ Pi Φ *< 01 P φ sn P Φ H Ω P. h H P* P tr Ω Pi 3* i H 01 3 o o φ P* φ *< rt φ P 1 rt 3 Pi P* o rt H P Φ Φ 3 tr 3" Pi Ω H •» tr 03 tr 0 P ft 3 o H Pi rt 01 P P* P* P P* P* P* o 3 3 3 rt fl 3 Φ rt 03 Φ P. 3 iP 01 3" P Pi € 01 Φ 01 UJ. 3* o rt 0 P 33 P H ιt Hi Ul. rt _: P* Ω O Φ P o 01 rt 3" ft 133 tr tr P Ω φ 03 3 3 φ Φ Ul TJ H 3* et Φ Pi P P* P P* P* tr rt P* ID rt i h TJ Ω φ 3" p 01 H P* It tr O y P fl φ 01 ft fit fl H 3 3 P P* Φ It Φ H P. Pi Φ position in relation to the cutting devices of the edging machine. |
| 3. | 4 A method according to any of Claims 13, characterized in that the useful width of the board is determined by detecting the positions of the jaws when gripping a board; and in that the position of respective devices is adjusted in accordance with said detected positions. |
| 4. | 5 A method according to Claim 4 when applied to an edging machine incorporating one fixed and one laterally movable saw blade, characterized in that subsequent to a board being gripped by the jaws the frame assembly is moved to a position in which the centre line between the jawcarrying legs is located at a distance from the fixed saw blade which is equivalent to half the width of the maximum board width that can be recovered from the unedged board, and in that the movable saw blade is moved laterally to a posi¬ tion in which it is located at the same distance from said centre line, but on the other side thereof. |
| 5. | 6 An arrangement for use in guiding an unedged board or like workpiece into, or aligning said board with, an edging machine which includes at least one pair of mutually co acting jaws (17) which can be brought into gripping engage¬ ment with the board (1) so as to grip said board therebe¬ tween, characterized in that those parts of the jaws intend ed for gripping engagement with the board comprise bodies (17) of resilient material; in that the gripping force exterted is uniformly distributed on the two jaws and so adapted in relation to the resiliency of said material that any wane present on the board (1) will be pressed into the resilient material of an associated jaw, such that the distance between the jaws (17) in gripping engagement with said board represents the useful width of the board and can be utilized to effect said guidance or alignment of the board. |
| 6. | 7 An arrangement according to Claim 6, characterized in that the jaws (17) are supported on legs (14) which are pivotally mounted on a frame assembly (9) and which can be positively pivoted in relation to an intermediate centre line which corresponds essentially with the centre line representative of the useful width of a board (1) gripped between the jaws (17); and in that said frame assembly (9) can be displaced so as to bring the centre line represen¬ tative of the useful width of the board into the desired . position of alignment relative to the cutting devices (5, 6) of the edging machine (2) , by commensurate steering of the position of the centre line between the legs (14) . |
| 7. | 8 An arrangement according to Claim 6 or 7, character¬ ized by means (24, 25) for determining the positions of the jaws (17) in gripping engagement with a board (1) and therewith determining the useful width of the board; and by means (13) for displacing the frame assembly (9), in response thereto, relative to the cutting devices (5, 6) of the edging machine and for adjusting the distance between said devices. |
| 8. | 9 An arrangement according to Claim 7 or Claim 8, characterized in that the legs (14) are mutually connected via two coacting toothed segments (21, 22) with respec¬ tive centres located in the pivot point of associated legs. |
| 9. | 10 An arrangement according to any of Claims 69, char¬ acterized in that said resilient jaw parts (17) comprise airfilled casings made of rubber, plastic or like ateri al. |
The present invention relates to a method by which unedged sawn board or like material is brought into alignment with an edging machine, and by which the useful width of the board is determined with the aid of at least one pair of mutually co-acting jaws which are brought into engagement with the board so as to grip the board therebetween. The invention also relates to an arrangement of apparatus and of devices for use when aligning a board in accordance with the method.
Unedged sawn boards, such as planks or like timber lengths, here referred to collectively as boards, are edged by pass¬ ing the boards through an edging machine, which normally comprises two mutually spaced saw blades or cutting blades with which wanes orlike edge defects are removed from the boards. In order to obtain the best possible yield from an unedged board, it is essential that as much as possi¬ ble of the planar part of the unedged board is recovered, this planar board part being referred to hereinafter as the useful width. Since, for instance, the width or depth extension of the wane or other edge defect of an unedged board varies between the two mutually opposing edges of the board, it is not possible to centre the board in relation to the cutting tools of the edging machine with a starting point from the centre line of the unedged board. Instead, the board must be centred with reference to an offset or dis¬ placed centre line which represents the centre line of the useful width of the board.
Known arrangements for guiding a board automatically into an edging machine or aligning a board inrelation thereto, with the aim of obtaining optimal yield, are relatively compli-
cated and are based on the use of electronic devices that incorporate photocells, comparators, memory stores, and the like. Such arrangements can only be used in conjunc¬ tion with large saw mills and are relatively sensitive to ambient, environmental conditions. In the case of small saw mills, or saw mills of average size, it is normally necessary to judge the useful width of a board visually and to align and guide the board manually into the edging machine.
The main object of the present invention is to provide a method and an arrangement which will enable an unedged sawn board to be automatically aligned with and guided into an edging machine, in a manner to obtain maximum yield, without requiring the application of complicated expensive and environmentally sensitive technology.
To this end it is proposed in accordance with the inven¬ tion that when applying the aforedescribed method those parts of the jaws that are intended to grip the board con¬ sist of resilient bodies, that the gripping force exerted by the jaws is distributed uniformly thereon and is so adapted in relation to the resiliency of the material that any wane located on the board will be pressed into the resilient material of an associated jaw, and that the resul¬ tant distance between the mutually opposing jaws is used as a measurement of the useful width of the board when aligning the board relative to the edging machine, for subsequent guidance thereinto.
This method can be carried out purely mechanically with the aid of simple and reliable devices that are construc- ted from known and well tried components which will not be negatively influenced by the environment of a saw mill.
When carrying out the inventive method the centre line representing the useful width of the unedged board is preferably utilized for aligning the board in relation to the cutting devices of the edging machine, so as to obtain downstream of the edging machine an edged board whose centre line coincides with the first mentioned centre line.
The board gripping jaws are preferably carried by two pivotable legs which can be swung positively in relation to an intermediate centre line, wherewith this centre line can be used as the centre line which is representative of the useful width of a board gripped by th ' e jaws, thereby enabling the board to be aligned with the cutting devices by displacing the frame in a manner to bring the centre line extending between the jaw-carrying legs to a desired position relative to the cutting devices of the edging machine.
The useful width of the board is determined conveniently by detecting the resultant positions of the jaws when gripping the board, whereafter the positions of the cutting devices of the edging machine can be adjusted accordingly.
In accordance with one particularly preferred embodiment of a method according to the invention applied with an edging machine of the kind which employs a fixed saw blade and a laterally movable saw blade, the frame, subsequent to engagement of the jaws with the board, is moved to a position in which the centre line between the jaw-carrying legs is located from the fixed saw blade at a distance which corresponds to half the width of the maximum useful board width of the unedged board, and the laterally movable blade is moved to a position located at the same distance from the centre line, but on the opposite side thereof.
The resilient bodies provided on respective jaws may com¬ prise air-filled casings of rubber, plastic or some equivalent material, and means may be provided for varying the pressure of the air in the casings in accordance with the anticipated width and thickness of the wane of a board or like wooden workpiece.
The invention also relates to an arrangement of apparatus and devices for use when carrying out the method. The features particularly characteristic of the arrangement are set forth in the following apparatus claims.
The invention will now be described in more detail with reference to the accompanying drawings.
Figure 1 is a perspective illustration of an arrangement constructed in accordance with the invention, and
Figures 2-5 are cross-sectional views of a pair of jaws included in the arrangement of Figure 1 and shown in grip¬ ping engagement with boards which exhibit mutually dif¬ ferent edge defects.
The arrangement illustrated in Figure 1 is intended for bringing an unedged board 1 into a desired position of alignment with an edging machine 2, and feeding said unedged board into the machine. The arrangement in¬ cludes two serrated or fluted feed drums 3 and 4 which clamp the board 1 firmly therebetween and advance the board into the vicinity of two cutting devices, which in the illustrated embodiment have the form of saw blades 5 and 6. Both of the illustrated blades 5 and 6 are later¬ ally adjustable, so that the blades can be brought to positions corresponding to the desired width dimension of the board, although normally one of the blades, 5, is
fixedly located while the other blade, 6, is movable laterally in relation to the first mentioned blade.
Since the two saw blades are movable symmetrically in relation to an intermediate centre line, the board 1 need only be aligned so that the centre line representing the useful width of the board coincides with the centre line between the saw blades 5 and 6, while the mutual distance between the saw blades is adjusted to the maximum width that can be recovered from the unedged board 1.
In those cases where only the saw blade 6 is laterally movable, it is necessary to determine the position of the board 1 such that the distance from the centre line along the useful width of the board 1 to the laterally fixed blade 5 corresponds to half the width of the maximum board width that can be recovered, and the laterally mov¬ able blade 6 is moved to a corresponding distance from the centre line, but on the opposite side thereof.
To this end the arrangement illustrated in Figure 1 in¬ cludes a frame assembly, generally shown at 9, which is movably mounted on guides 7 and 8 and which incorporates an upper frame 10, which is guided on said guides, and a lower frame 11 , which is suspended from the upper frame 10 by means of rigid cross-struts 12. The whole of the frame assembly 9 can be moved reciprocatingly on the guides 7 and 8 with the aid of an accurately steered piston-cylin¬ der device 13.
In the illustrated embodiment the lower frame 11 of the frame assembly has depending therefrom three pairs of pivotably mounted legs 14, 15 and 16, each of which can be pivoted or swung in relation to the other. Provided on the lower end of respective legs is a jaw 17 which is made from
a resilient or elastic material and which is intended for gripping engagement with a respective side edge of the illustrated board 1.
As will be seen from Figure 1 , the frame assembly 9 can be moved laterally to the left in said Figure, so as to collect a board 1 advanced on a board conveyor 18, where¬ upon the board is gripped by the jaws 17 and, as the frame assembly is moved to the right in the Figure 1 , lifted onto rollers 19, which feed the board into the edging machine 2. The board 1 is held in a correct position of alignment in relation to the edging machine with the aid of two toothed wheels 20, which press the board against the rollers, such as to maintain the position of alignment of the board when the jaws 17 release their hold thereon.
The upper ends of the legs 14 are pivotably mounted in the lower frame 11 at the centre of a respective toothed seg¬ ment 21 and 22, which mesh with each other. The leg connected to the toothed segment 21 is also by an arm 23 connected to the piston rod 24 of an auxiliary piston-cylinder device 25 mounted on the upper frame 10 of the frame assembly 9. Consequently, as the piston rod 24 moves in its axial direction the legs 14 will be symmetrically moved in a corresponding direction towards or away from each other while centred around the centre line between the leg sus- pension points, due to the positive steering of the legs in relation to one another achieved through the mutual meshing engagement of the toothed segments 21 and 22. The pairs of legs 15, 16 are suspended from the lower frame 1 ' 1 and positively steered and manipulated in a manner cor- responding to that described with regard tσ the leg pair 14.
In order to align a board exactly, the arrangement must
incorporate at least two pairs of legs, suitably one pair of legs at each end of the board. Consequently, the intermediate leg pair 15 of the Figure 1 embodiment need only be used when edging a board which is too short to extend from the legs 16 to the legs 14. The reference 26 identifies a pivot device which enables adjustments to be made to the angle at which respective jaws of an associated leg pair engage the board.
As beforementioned, the jaws 17 are made of, or comprise, a resilient material, such that a wane or like edge defect present on the board to be edged will be pressed into the jaw in engagement therewith. Consequently, when a board is gripped between the jaws, the useful width of the board can be determined by detecting the movement carried out by the piston rod 24, or the terminal position of the piston rod. Furthermore, it is known that the line passing along the centre of the useful width of the board 1 coincides essentially with the centre line between the pivot axes of the toothed segments 21 and 22. This is illustrated more closely in Figures 2-5.
In Figure 2, the jaws 17 are shown gripping a board 1 having planar side edges. As seen from this Figure, the gripping force acting on the legs 14 is adapted so that the edges of the board 1 will not be pressed into the resilient jaws 17 to any appreciable extent. Consequently, the centre line A-A representing the useful width of the board 1 , which in this case coincides with the centre line representing the total width of the illustrated board, will coincide with the centre line between the legs 14.
Figure 3 illustrates a board with which the opposing side edges thereof have mutually different wane configurations. In this case the gripping force is adapted so that the
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blades 5 and 6. The distance between the blades is there¬ with adjusted in accordance with the detected width of the board which is obtained from the auxiliary piston- cylinder device 25. Movement of the piston rod 24 and its terminal position can be determined, to this end, in some suitable known manner and the resultant value used to control the adjustment of the saw blades.
When using an edging machine 2 in which one blade, 5, is immovable, the procedure followed is essentially the same as before, although with the exception that in this case subsequent to gripping a board the frame assembly 9 is displaced to a position in which the frame assembly centre line is located at a distance from the fixed blade 5 equivalent to half the known useful width of the board 1. The other blade 6 is then moved to a position in which the blade is located at a corresponding distance from said centre line, but on the opposite side thereof. Movement of the frame assembly 9 with the aid of the piston-cylin¬ der device 13, and displacement of the saw blade 6 are also in this case steered on the basis of signals received from the auxiliary piston-cylinder device 25.
When the widths of the mutually opposite ends of an un¬ edged board vary, the useful width of the board and said centre line are determined by means of the resilient jaw 17 in engagement with the narrowest end of the board. The jaws 17 located at the other end of the board are there¬ with adjusted with the aid of the associated legs, on the basis of those width determinations made at the narrowest end of the board. It will be understood that the above description made with reference to the legs 14 and associ¬ ated piston-cylinder device 25 also applies to the legs 16 and its associated auxiliary piston-cylinder device, and in the case of short planks also to the legs 15 with as-
sociated auxiliary piston-cylinder device.
Thus, it is those jaws which detect the smallest width of a board that control the subsequent aligning procedure. Should the jaws of one jaw pair located at one of the extremes meet one another during a board aligning process, this indicates that the board is too short to reach be¬ tween the pairs of jaws located at the extremities and a signal is subsequently sent to the piston-cylinder device which controls the intermediate legs 15, so as to bring the jaws attached thereto into gripping engagement with the board.
Although the invention has been described with reference to a preferred embodiment thereof, it will be understood that this embodiment is not restrictive in any way and that modifications can be made within the scope of the following claims. For example, the legs 14 may be sus¬ pended and positively steered in relation to one another in a manner different to that illustrated, and the posi¬ tion of the auxiliary piston-cylinder devices may be varied so that said devices, e.g., engage directly be¬ tween the legs. The piston-cylinder devices used may be either pneumatically operated or hydraulically operated devices. The resilient jaws 17 may comprise homogenous bodies of resilient material, instead of the air-filled bladder-like casings of rubber, plastic or like material from which the illustrated jaws are comprised. Thus, the jaws may have any desired form and can be made from expanded rubber having closed cells.