GB2345026A - Apparatus for manufacturing lumber products - Google Patents

Abstract

The apparatus (1) comprises a log scanner (9) for measuring each log which is stockpiled according to size. A debarker (32) is provided for stripping the bark from each log. A log machining conveyor (39) downstream of the debarker (32) is operable to transport debarked logs sequentially through a number of log machining stations (40, 43, 45, 50, 52). A first chipper (40) cuts away excess material from opposite sides of the log leaving a pair of flat side faces on the log. After rotation of the log through 90{ in a turntable (42), a second chipper (43) cuts away excess material from the remaining two rounded log faces leaving said faces flat. A first router (45) cuts rebates along each corner of a log and associated cutter blades part scale boards from each side of the log. After rotation through 90{ in a second turntable (48), the log is passed through a second router (50) which rebates the corners of the log with associated cutter blades then parting scale boards from opposite sides of the log. A log divider (52) then cuts the log into boards of a desired thickness which are cut to length in cross cut saws (55).

Description

"An apparatus for manufacturing lumber products" Introduction This invention relates to apparatus and a method for producing machined lumber products.

It is an object of the invention to provide apparatus for manufacturing lumber products from relatively low yield lumber in an efficient and cost effective manner.

Statements of Invention According to the invention, there is provided apparatus for manufacturing lumber products comprising : a log scanner for measuring selected dimensions of each log, a scanning conveyor for delivering each log longitudinally through the scanner, and downstream of the scanner means for discharging logs from the scanning conveyor into one of a number of stock piles in response to the dimensional information sensed by the scanner; a log debarker for stripping the bark off each log ; a log machining conveyor for transporting debarked logs sequentially through a number of log machining stations comprising : a first chipper having a pair of spaced-apart chipping blades engagable with opposite sides of a log to cut away a desired amount of excess material from the log leaving a pair of flat substantially parallel side faces on the log, a turntable having means to sense the presence of a log, means to grip the sensed log and rotate the log through 901 about a longitudinal axis of the log and then release the log, a second chipper having a pair of spaced-apart chipping blades engagable with opposite sides of a log to cut away a desired amount of excess material from the curved faces of the log leaving a pair of flat substantially parallel side faces on the log, a first router having a set of router blades engagable with each corner of the log to cut a rebate of a preselected size along each corner of the 'og, an associated scale board cutter immediately downstream of the first router having a pair of spaced-apart cutter blades rotatable about a horizontal axis for parting scale boards from-each side of the log leaving flat side faces on the log, with means for delivering said scale boards to a cross-cut saw operable to cut the scale boards to preset desired lengths, a second turntable downstream of the first router having means to sense the presence of a log, means to grip the sensed log and rotate the log through 90 about a longitudinal axis of the log and then release the log, a second router having a set of router blades engagable with each corner of the log to cut a rebate of a preselected size along each corner of the log, an associated scale board cutter immediately downstream of the second router having a pair of spaced-apart rotatable cutter blades for parting scaleboards from each side of the log leaving flat side faces on the log, with means for delivery of said scale boards to a cross-cut saw operable to cut the scale boards to preset desired lengths, ../ a log divider downstream of the second router having a number of spaced-apart rotatable cutting blades engagable with the log to divide the log into a number of boards of a preset desired size, and a cross-cut saw downstream of the log divider.

In a particularly preferred embodiment, the apparatus includes a log preparation station immediately upstream of the log machining conveyor, comprising an inlet conveyor for reception of logs, the conveyor having a number of spaced-apart endless log feed chains with associated drive means for the chains, the log feed chains discharging onto an upwardly inclined conveyor having a number of spacedapart fixed step plates with complementary movable step plates mounted therebetween, a ram being operable to move the movable step plates relative to the fixed step plates to lift a log from a fixed step up or) to the next higher step, an uppermost step of the inclined conveyor discharging on to a debarker feed conveyor for log delivery through the debarker, and a discharge conveyor for carriage of stripped logs downstream of the debarker onto the log machining conveyor.

In another embodiment, log sensor means is provided downstream of the debarker operable to stop the debarker feed conveyor when a log is sensed on the discharge conveyor.

In a further embodiment, log sensor means is provided at an inlet of the debarker feed conveyor, the ram means for the inclined conveyor being stopped in response to the log sensing means detecting a log at the inlet of the debarker feed conveyor.

In another embodiment, the log feed chains are movable along channel supports and around a drive sprocket at an outlet end of the conveyor-and an arcuate weigher strip at an inlet end of the conveyor.

Preferably, each drive sprocket is mounted on a common drive shaft and said drive shaft has a ratchet wheel driven by a ram operated reciprocating drive arm.

In another embodiment, a catchment bin is located beneath the log feed chains with a scraper bar movable through the bin to discharge collected waste materials from the bin.

In a further embodiment, a waste material collection conveyor is mounted beneath the log machining conveyor for collection and delivery of wood off-cuts to a screen which discharges into a waste collection bin, oversize materials being delivered through a waste chipper prior to return to the screen.

In another embodiment, means are provided for delivery of offcut materials from the cross-cut saws through the waste chipper.

In another aspect, the invention provides a process for manufacturing lumber products comprising the steps: delivering logs to a log scanner for measuring selected dimensions of each log, delivering each log longitudinally through the scanner on a scanning conveyor, downstream of the scanner, discharging logs from the scanning conveyor into one of a number of stock piles in response to the dimensional information sensed by the scanner; delivering each log through a log debarker for stripping the bark off each log ; mounting debarked logs on a log machining conveyor for transporting debarked logs sequentially through a number of log machining stations comprising: a first chipper having a pair of spaced-apart chipping Jades engagable with opposite sides of a log for cutting away a desired amount of excess material from the Jlog ieaving a pair of flat substantially parallel side faces on the log, a turntable having means for sensing the presence of a log, means for gripping the sensed log and rotating the log through 9CP about a longitudinal axis of the log and then releasing the log, a second chipper having a pair of spaced-apart chipping blades for engaging with opposite sides of a log to cut away a desired amount of excess material from the curved faces of the log leaving a pair of flat substantially parallel side faces on the log, a first router having a set of router blades for engaging with each corner of the log for cutting a rebate of a preselected size along each corner of the log, an associated scale board cutter immediately downstream of the first router having a pair of spaced-apart cutter blades rotatable about a horizontal axis for parting scale boards from each side of the log leaving flat side faces on the log, with means for delivering said scale boards to a cross-cut saw operable for cutting the scale boards to preset desired lengths, a second turntable downstream of the first router having means for sensing the presence of a log, means for gripping the sensed log and rotating the log through 90 about a longitudinal axis of the log and then releasing the log, a second router having a set of router blades for engaging with each corner of the log for cutting a rebate of a preselected size along each corner of the log, an associated scale board cutter immediately downstream of the second router having a pair of spaced-apart rotatable cutter blades for parting scaleboards from each side of the log leaving flat side faces on the log, with means for delivering said scale boards to a cross-cut saw operable for cutting the scale boards to preset desired lengths, i a log divider downstream of the second router having a number of spaced-apart rotatable cutting blades for engaging with the log for dividing the log into a number of boards of a preset desired size, and a cross-cut saw downstream of the log divider for cutting the boards to a desired length.

In a preferred embodiment, the process includes the step of delivering the logs through a log preparation station immediately upstream of the log machining J conveyor, comprising an inlet conveyor for receiving logs, the conveyor having a number of spaced-apart endless log feed chains with associated drive means for the chains, the log feed chains discharging onto an upwardly inclined conveyor having a number of spaced-apart fixed step plates with complementary movable step plates mounted therebetween, a ram being operable to move the movable step plates relative to the fixed step plates for lifting a log from a fixed step up onto the next higher step, an uppermost step of the inclined conveyor discharging on to a debarker feed conveyor for delivering logs through the debarker, and a discharge conveyor for carrying stripped logs downstream of the debarker onto the log machining conveyor.

In another embodiment, a waste material collection conveyor is mounted beneath the log machining conveyor, and the process includes for collecting and delivering wood off-cuts to a screen which discharges into a waste collection bin, oversize materials being delivered through a waste chipper prior to return to, the screen.

In a further embodiment, the process includes delivering offcut materials from the cross-cut saws through the waste chipper.

Detailed Description of the Invention The invention will be more clearly understood by the following description of some embodiments thereof, given by way of example only, with reference to the accompanying drawings, in which: . 0 Fig. 1 is a plan view of apparatus according to the invention; Fig. 2 is a perspective view of a log sorting station forming portion of the apparatus; Fig. 3 is a detail perspective view of portion of the log sorting station; Fig. 4 is a perspective view of a debarking and machining production line forming portion of the apparatus ; Fig. 5 is a detail perspective view of debarking apparatus according to the invention; .

Fig. 6 is a perspective view of a log feed conveyor for the debarking apparatus; Fig. 7 is a detail perspective view of an outlet end of the machining production line ; and Fig. 8 is a view similar to Fig. 4 showing a waste recovery system in broken outline.

Referring to the drawings, there is illustrated apparatus for manufacturing lumber products according to the invention, indicated generally by the reference numeral 1.

The apparatus 1 comprises a log sorting station 2 for measuring the size of logs and sorting the logs into stock piles of a number of preselected different sized logs.

Downstream of the sorting station 2 is a debarking apparatus 3 for stripping the bark off the logs prior to delivery of the debarked logs through log machining apparatus 4 for shaping the logs and cutting the logs into timber articles of selected sizes.

The sorting station 2 has a conveyor 6 for delivery of logs 7 onto a sorting conveyor 8.

The conveyor 8 delivers logs 7 longitudinally through a scanner 9 for measuring the size of each log 7, the dimensional information being sent to a controller (not shown) which determines the volume of wood in the log 7. Downstream of the scanner 9, each log 7 according to its measured size is delivered into one of a number of stock piles 10. Each stock pile 10 contains logs in different preselected sizes. A number of sets of deflector arms 12 are rotatably mounted above he conveyor 8. Each set of arms 12 is mounted on a rotatable support 13 having an associated actuating mechanism 14 operable by the controller in response to sensed log size. As the log 7 on the conveyor 8 reaches the required stock pile 10, the appropriate arms 12 rotate to deflect the log 7 from the conveyor 8 onto the stock pile 10.

A batch of logs 7 from a selected stock pile 10 are delivered to the debarking apparatus 3 (Fig. 5). The debarking apparatus 3 has an input conveyor 20 comprising a number of spaced-apart endless conveyor chains 21 running in associated channel guides which deliver logs from an inlet 22 to an outlet end 23 of the conveyor 20.

Each chain 21 passes around a drive sprocket on a drive shaft having a ratchet drive 28 comprising a ratchet wheel driven by a ram operated reciprocating drive arm. The spacing between the conveyor belts 21 allows strips of lose bark and foreign matter to drop downwardly between the chains 21 for collection beneath the conveyor 20 in a J waste catchment bin 24. A pair of spaced-apart scraper beams 25 are carried at each side of the bin 24 on endless drive belts 26 mounted on associated tracks 27 and slowly traverse the tray 24 to collect and push any collected material onto a waste collection conveyor 29.

Logs discharged from the conveyor 20 are delivered individually by an inclined conveyor 30 onto a feed conveyor 31 which delivers the logs through de-barking apparatus 32. The inclined conveyor 30 has a number of spaced-apart fixed step plates with complementary movable step plates mounted therebetween. A ram (not shown) is operable to move the movable step plates back and forth relative to the fixed step plates to lift a log from a fixed step up onto the next higher fixed step. Log sensing means is provided at an inlet of the feed conveyor 31. This sensor is connected to a controller for the ram to stop the ram and hence the movable step plates when a log is sensed at the inlet of the feed conveyor 31. This prevents a pile up of logs at an inlet to the debarker 32. The debarker 32 has rotating sets of spiked rollers 33 engage and strip the bark from each log as it passes through the debarking apparatus 32 and then discharge the debarked log to a machine line feeder 35. Each log is delivered by a discharge conveyor 34 against a sensor plate 36 which then actuates a cross feed conveyor 37 to deliver the log onto a step-up conveyor 38 which positions the log at the start of the machining line 4. It will be noted that the conveyors 30,31 are switched off until the line downstream of the debarking apparatus 32 is clear to prevent a backlog of stripped logs on conveyor 34 preventing a debarked log being discharged from the debarker 32 as the rotating rollers 33 would cut the log in two. A direct infeed conveyor 36 is provided for direct infeed of prestripped logs to the machining line if required.

The log machining apparatus 4 has a log machining conveyor 39 for transporting debarked logs sequentially through a number of log machining stations. A first chipper 40 has a pair of spaced-apart chipping blades engagable with opposite sides of a log to cut away excess material from the log imparting flat side faces to the log as it passes through the chipper 40. Downstream of the first chipper 40, a turntable 42 rotates the log through 90 so that it fits on its flat face with the two rounded faces at the sides. The log is then delivered through a second chipper 43. In passing through the second chipper 43, the log passes between a pair of chipping blades which engage with the rounded sides of the log to cut away excess material leaving flat substantially parallel side faces of the log. At this stage, the log is substantially rectangular but has rounded corners. The log is then delivered through a first router 45 having a set of router blades engagable with each corner of the log to cut a rebate of a preselected size along each corner of the log. Immediately downstream of the router 45, an associated scale board cutter has a pair of rotatable cutter blades which cut away scale boards from each side of the log leaving flat side faces on the log. As the log is delivered along the conveyor, the scale boards fall away to each side and are delivered by conveyors to a cross-cut saw in which the scale boards are cut to a preset desired length. A second turntable 48 downstream of the first router has means to sense the presence of a log. As the log locates in the turntable, a clamp grips the log and rotates the log through 9Cf so that the longer side face is sitting on the conveyor. The log is then delivered through a second router 50. This second router is similar to the first router and has a set of router blades engagable with each corner of the log to cut a rebate of a preselected size along each corner of the log.

Again, immediately downstream of the routers, associated scale board cutters part away scale boards from each side of the log leaving, flat side faces on the log.

Downstream of the router 50, the scale boards are allowed to peel away from the log and are delivered by conveyors to a cross-cut saw for cutting to a required length. A log divider 52 is provided downstream of the second router 50 and has a number of spaced-apart rotatable cutting blades which are engagable with the log to divide the log longitudinally as it passes through the divider 52 into a number of boards of a preset desired size. These boards are then delivered on to a cross-cut saw 55 for cutting to a required length. If desired, the cutting blades of the divider 52 may be retracted so that a rectangular timber piece of a desired dimension is discharged to the cross-cut saw 55. l It will be noted particularly from Fig. 8 that a waste material collection conveyor 60 is mounted beneath the log machining conveyor 39 for collection and delivery of wood chips and sawdust to a screen 62 which discharges into a waste collection bin. Any oversize materials from the screen are delivered through a waste chipper prior to return to the screen 62. Means is also provided for delivering offcut materials from all the cross-cut saws 55 through the waste chipper and then to the screen 62 for recovery of the waste materials from the cross-cut saws.

It will be appreciated that the invention provides an efficient apparatus for the processing of lumber with a view to maximising the useful yield from the original tree trunks.

The invention is not limited to the embodiments hereinbefore described which may be l varied in both construction and detail.

Claims (16)

1. CLAIMS 1. Apparatus for manufacturing lumber products comprising: a log scanner for measuring selected dimensions of each log, a scanning conveyor for delivering each log longitudinally through the scanner and downstream of the scanner means for discharging logs from the scaining conveyor into one of a number of stock piles in response to the dimensional information sensed by the scanner; a log debarker for stripping the bark off each log ; a log machining conveyor for transporting debarked logs sequentially through a number of log machining stations comprising : a first chipper having a pair of spaced-apart chipping blades engagable with opposite sides of a log to cut away a desired amount of excess material from the log leaving a pair of flat substantially parallel side faces on the log, a turntable having means to sense the presence of a log, means to grip the sensed log and rotate the log through 9 (F about a longitudinal . l axis of the log and then release the log, a second chipper having a pair of spaced-apart chipping blades engagable with opposite sides of a log to cut away a desired amount of excess material from the curved faces of the log leaving a pair of flat substantially parallel side faces on the log, a first router having a set of router blades engagable with each corner of the log to cut a rebate of a preselected size along each corner of the log, an associated scale board cutter immediately downstream of the first router having a pair of spaced-apart cutter blades rotatable about a horizontal axis for parting scale boards from each side of the log leaving flat side faces on the log, with means for delivering said scale boards to a cross-cut saw operable to cut the scale boards to preset desired lengths, a second turntable downstream of the first router having means to sense the presence of a log, means to grip the sensed log and rotate the log through 90 about a longitudinal axis of the log and then release the log, l a second router having a set of router blades engagable with each corner of the log to cut a rebate of a preselected size along each corner of the log, an associated scale board cutter immediately downstream of the second router having a pair of spaced-apart rotatable cutter blades for parting scaleboards from each side of the log leaving flat side faces on the log, with means for delivery of said scale boards to a cross-cut saw operable to cut the scale boards to preset desired lengths, a log divider downstream of the second router having a number of spaced-apart rotatable cutting blades engagable with the log to divide the log into a number of boards of a preset desired size, and l a cross-cut saw downstream of the log divider.
2. 2. Apparatus as claimed in claim 1, including a log preparation station immediately upstream of the log machining conveyor, comprising an inlet conveyor for reception of logs, the conveyor having a number of spaced-apart endless log feed chains with associated drive means for the chains, the log feed chains discharging onto an upwardly inclined conveyor having a number of spaced-apart fixed step plates with complementary movable step plates mounted therebetween, a ram being operable to move the movable step plates relative to the fixed step plates to lift a log Irom a fixed step up onto the next higher step, an uppermost step of the inclined conveyor discharging on to a debarker feed conveyor for log delivery through the debarker, and a discharge conveyor for carriage of stripped logs downstream of the debarker onto the log machining conveyor.
3. 3. Apparatus as claimed in claim 1 or 2, wherein log sensor means is provided downstream of the debarker operable to stop the debarker feed conveyor when a log is sensed on the discharge conveyor.
4. 4. Apparatus as claimed in any preceding claim, wherein log sensor means is provided at an inlet of the debarker feed conveyor, the ram means for the inclined conveyor being stopped in response to the log sensing means detecting a log at the inlet of the debarker feed conveyor.

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5. 5. Apparatus as claimed in any precedhg claim wherein the log feed chains are movable along channel supports and around a drive sprocket at an outlet end of the conveyor and an arcuate weigher strip at an inlet end of the conveyor.
6. 6. Apparatus as claimed in claim 5, wherein each drive sprocket is mounted on a common drive shaft and said drive shaft has a ratchet wheel driven by a ram operated reciprocating drive arm.
7. 7. Apparatus as claimed in any preceding claim, wherein a catchment bin is located beneath the log feed chains with a scraper bar movable through the bin to discharge collected waste materials from the bin.
8. 8. Apparatus as claimed in any preceding claim, wherein a waste material collection conveyor is mounted beneath the log machining conveyor for collection and delivery of wood off-cuts to a screen which discharges into a waste collection bin, oversize materials being delivered through a waste chipper prior to return to the screen.
9. 9. Apparatus as claimed in any preceding claim, wherein means is provided for delivery of offcut materials from the cross-cut saws through the waste chipper.
10. 10. Apparatus substantially as hereinbefore described with reference to the accompanying drawings.
11. 11. A process for manufacturing lumber products comprising the steps: delivering logs to a log scanner for measuring selected dimensions of each log, delivering each log longitudinally through the scanner on a scanning conveyor, downstream of the scanner, discharging logs from the scanning conveyor into one of a number of stock piles in response to the dimensional information sensed by the scanner; delivering each log through a log debarker for stripping the bark off each log ; J mounting debarked logs on a log machining conveyor for transporting debarked logs sequentially through a number of log machining stations comprising : a first chipper having a pair of spaced-apart chipping blades engagable with opposite sides of a log for cutting away a desired amount of excess material from the log leaving a pair of flat substantially parallel side faces on the log, a turntable having means for sensing the presence of a log, means for gripping the sensed log and rotating the log through 90"about a longitudinal axis of the log and then releasing the log, a second chipper having a pair of spaced-apart chipping blades for engaging with opposite sides of a log to cut away a desired amount of excess material from the curved faces of the log leaving a pair of flat substantially parallel side faces on the log, a first router having a set of router blades for engaging with each corner of the log for cutting a rebate of a preselected size along each corner of the log, an associated scale board cutter immediately downstream of the first router having a pair of spaced-apart cutter blades rotatable about a horizontal axis for parting scale boards from each side of the log leaving flat side faces on the log, with means for delivering said scale boards to a cross-cut saw operable for cutting the scale boards to preset desired lengths, a second turntable downstream of the first router having means for sensing the presence of a log, means for gripping the sensed log and rotating the log through 91Y about a longitudinal axis of the log and then releasing the log, a second router having a set of router blades for engaging with each corner of the log for cutting a rebate of a preselected size along each corner of the tog, an associated scale board cutter immediately downstream of the second router having a pair of spaced-apart rotatable cutter blades for parting scaleboards from each side of the log leaving flat side faces on the log, with means for delivering said scale boards to a cross-cut saw operable for cutting the scale boards to preset desired lengths, a log divider downstream of the second router having a number of spaced-apart rotatable cutting blades for engaging with the log for dividing the log into a number of boards of a preset desired size, and a cross-cut saw downstream of the log divider for cutting the boards to a desired length.
12. 12. A process as claimed in claim 11, including the step of delivering the logs through a log preparation station immediately upstream of the log machining conveyor, comprising an inlet conveyor for receiving logs, the conveyor having a number of spaced-apart endless log feed chains with associated drive means for the chains, the log feed chains discharging onto an upwardly inclined conveyor having a number of spaced-apart fixed step plates with complementary movable step plates mounted therebetween, a ram being operable to move the movable step plates relative to the fixed step plates for lifting a log from a fixed step up onto the next higher step, an uppermost step J of the inclined conveyor discharging on to a debarker feed conveyor for delivering logs through the debarker, and a discharge conveyor for carrying stripped logs downstream of the debarker onto the log machining conveyor.
13. 13. A process as claimed in claim 11 or 12, wherein a waste material collection conveyor is mounted beneath the log machining conveyor, and the process includes for collecting and delivering wood off-cuts to a screen which discharges into a waste collection bin, oversize materials being delivered through a waste chipper prior to return to the screen.
14. 14. A process as claimed in any of claims 11 to 13, wherein the process includes delivering offcut materials from the cross-cut saws through the waste chipper.
15. 15. A process for manufacturing lumber products substantially as hereinbefore described with reference to the accompanying drawings.
16. 16. Lumber products whenever produced by the process as claimed in any of claims 11 to 15.