CA2121401C - Tilt cradle breakdown hoist - Google Patents
Tilt cradle breakdown hoistInfo
- Publication number
- CA2121401C CA2121401C CA 2121401 CA2121401A CA2121401C CA 2121401 C CA2121401 C CA 2121401C CA 2121401 CA2121401 CA 2121401 CA 2121401 A CA2121401 A CA 2121401A CA 2121401 C CA2121401 C CA 2121401C
- Authority
- CA
- Canada
- Prior art keywords
- stack
- arms
- hoist
- inclined face
- translatable
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B65—CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
- B65G—TRANSPORT OR STORAGE DEVICES, e.g. CONVEYORS FOR LOADING OR TIPPING, SHOP CONVEYOR SYSTEMS OR PNEUMATIC TUBE CONVEYORS
- B65G59/00—De-stacking of articles
- B65G59/08—De-stacking after preliminary tilting of the stack
Landscapes
- Stacking Of Articles And Auxiliary Devices (AREA)
- Processing And Handling Of Plastics And Other Materials For Molding In General (AREA)
Abstract
A method of breakdown hoist for breaking down a stack of tiered material has an inclined face with upper and lower edges, the stack of tiered material translatable over the inclined face between the upper and lower edges, a supporting frame supporting the inclined face, a rotatable stack receiving cradle for receiving the stack of tiered material from a stack transfer device and rotating the stack of tiered material into slidable engagement with the inclined face, a translatable hoist arm translatable along the inclined face for translating the stack of tiered material between the upper edge and the lower edge in a direction towards the upper edge on the inclined face, and means for translating the translatable hoist arm along the inclined face, the hoist arm rotatable between a recessed position recessed beneath the inclined face and a stack translat-ing position substantially perpendicular to the inclined face, whereby when in the stack translating position the hoist arm may engage an underside surface of the stack of tiered material and slide the stack of tiered material over the inclined face towards the upper edge of the inclined face so as to deposit the tiered material over the upper edge.
Description
21214~ l .
TILT ~nT.~ R~RnOWN HOI8T
Field of the Invention This invention relates to the field of saw mill machinery and in particular to an apparatus for breaking down stacked and stickered rough lumber between the saw mill kiln and saw mill planer.
Background of the Invention It is known in the art to breakdown a stack of stacked and stickered lumber arriving on an infeed transfer chain by placing the stack on a rotatable hoist frame which may be rotated to incline the entire stack of lumber. The stack of lumber is then pushed by support arms up the inclined surface formed by the inclined hoist frame so as to discharge under the force of gravity rows or tiers of individual pieces of lumber from the top of the stack of lumber as the top of the stack of lumber is pushed beyond the uppermost end of the frame.
It is also known to assist pushing the stack of lumber towards the uppermost end of the frame so as to discharge tiers of lumber from the stack by providing secondary lumber stack support arms which at some intermediate transfer point take over the upward translation of the stack of lumber from the primary lumber stack support arms on the rotatable frame.
In particular, applicant is aware of United States Patent No. 4,838,748 which issued on June 13, 1989 to Johnson for a device entitled "Hoist and Accumulator Arm Apparatus". Johnson teaches a rotatable hoist frame for rotating a stack of tiered material, such as stacked and stickered lumber, from an upright position into an inclined position flush with an accumulator arm apparatus. Hoist frame horizontal support members translate up the incline to slide the load of tiered material upwards onto a similarly inclined frame surface on the accumulator arm appar-2121~01 atus. Retracted accumulator arms in the accumulator arm apparatus extend from the accumulator arm apparatus normal to the inclined frame surface once the load of tiered material has been slid from the hoist frame onto the accumulator arm apparatus.
The accumulator arms take the place of the hoist frame horizontal supports and slide the stack of tiered material further upwards to a discharge point at the uppermost edge of the accumulator arm apparatus. The accumulator arms then retract and are repositioned ready to accept the next stack of tiered material which has been transferred onto the hoist frame, rotated, and translated onto the accumulator arm apparatus.
Thus, it is an object of the present invention to provide a breakdown hoist which may be relatively quickly cycled so that delivery of lumber from stacks of lumber which have been broken down approaches a constant supply onto an outfeed transfer device, and incidental to this it is an object to provide an apparatus which does not require the rotation or tilting of the entire hoist frame. It is a further object to provide a breakdown hoist which reduces the probability of stacking sticks falling inside the hoist frame.
Summary of the Invention A breakdown hoist for breaking down a stack of tiered material has an inclined face such that a stack of tiered material may be translated by sliding upwards over the inclined face. A supporting frame supports the inclined face.
Tilt arms or other such rotatable stack receiving cradle receives the stack of tiered material from a stack transfer device such as an infeed chain. The tilt arms rotate the stack of tiered material into slidable engagement with the inclined face, that is, so that the stack of tiered material lies flush on its side on the inclined face.
TILT ~nT.~ R~RnOWN HOI8T
Field of the Invention This invention relates to the field of saw mill machinery and in particular to an apparatus for breaking down stacked and stickered rough lumber between the saw mill kiln and saw mill planer.
Background of the Invention It is known in the art to breakdown a stack of stacked and stickered lumber arriving on an infeed transfer chain by placing the stack on a rotatable hoist frame which may be rotated to incline the entire stack of lumber. The stack of lumber is then pushed by support arms up the inclined surface formed by the inclined hoist frame so as to discharge under the force of gravity rows or tiers of individual pieces of lumber from the top of the stack of lumber as the top of the stack of lumber is pushed beyond the uppermost end of the frame.
It is also known to assist pushing the stack of lumber towards the uppermost end of the frame so as to discharge tiers of lumber from the stack by providing secondary lumber stack support arms which at some intermediate transfer point take over the upward translation of the stack of lumber from the primary lumber stack support arms on the rotatable frame.
In particular, applicant is aware of United States Patent No. 4,838,748 which issued on June 13, 1989 to Johnson for a device entitled "Hoist and Accumulator Arm Apparatus". Johnson teaches a rotatable hoist frame for rotating a stack of tiered material, such as stacked and stickered lumber, from an upright position into an inclined position flush with an accumulator arm apparatus. Hoist frame horizontal support members translate up the incline to slide the load of tiered material upwards onto a similarly inclined frame surface on the accumulator arm appar-2121~01 atus. Retracted accumulator arms in the accumulator arm apparatus extend from the accumulator arm apparatus normal to the inclined frame surface once the load of tiered material has been slid from the hoist frame onto the accumulator arm apparatus.
The accumulator arms take the place of the hoist frame horizontal supports and slide the stack of tiered material further upwards to a discharge point at the uppermost edge of the accumulator arm apparatus. The accumulator arms then retract and are repositioned ready to accept the next stack of tiered material which has been transferred onto the hoist frame, rotated, and translated onto the accumulator arm apparatus.
Thus, it is an object of the present invention to provide a breakdown hoist which may be relatively quickly cycled so that delivery of lumber from stacks of lumber which have been broken down approaches a constant supply onto an outfeed transfer device, and incidental to this it is an object to provide an apparatus which does not require the rotation or tilting of the entire hoist frame. It is a further object to provide a breakdown hoist which reduces the probability of stacking sticks falling inside the hoist frame.
Summary of the Invention A breakdown hoist for breaking down a stack of tiered material has an inclined face such that a stack of tiered material may be translated by sliding upwards over the inclined face. A supporting frame supports the inclined face.
Tilt arms or other such rotatable stack receiving cradle receives the stack of tiered material from a stack transfer device such as an infeed chain. The tilt arms rotate the stack of tiered material into slidable engagement with the inclined face, that is, so that the stack of tiered material lies flush on its side on the inclined face.
2 1 ~
A translatable hoist arm translates the stack of tiered material by sliding the stack upwards over the inclined face in a direction towards the upper edge of the inclined face. The hoist arm is rotatable between a recessed position, wherein it is recessed beneath the inclined face, and a stack translating position, wherein the hoist arm is substantially perpendicular to the inclined face. When in the stack translating position the hoist arm engages the underside of the stack of tiered material which has been inclined flush with the inclined face.
The stack of tiered material is translated over the inclined face towards the upper edge of the inclined face. The tiered material is thus deposited over the upper edge of the inclined face onto an outfeed transfer device such as an outfeed chain. The hoist arm is then rotated into its recessed position and translated downwards along the inclined surface so as to reposition beneath the stack receiving cradle ready to rotate into its stack translating position so as to translate the next stack of tiered material upwards over the inclined surface.
Brief Description of the Drawings Figure 1 is a perspective partial cut-away view of the tilt cradle breakdown hoist of the present invention.
Figure 2 is a left side elevation view of the present invention with tilt arms upright and hoist arms discharging lumber.
Figure 3 is a left side elevation view with tilt arms in an inclined position and hoist arms recessed and positioned beneath tilt arms.
Figure 4 is a partial cut-away front elevation view of the breakdown hoist of Figure 1.
Figure 5 is a detailed view of a portion of Figure 4.
2121~01 Detailed Description of the Preferred Embodiment As illustrated in Figure 1, breakdown hoist 10 is positioned for breaking down lumber stack 12 when delivered to face 14 of breakdown hoist 10 via infeed transfer chains 16 on infeed transfer frame 18. It is the purpose of breakdown hoist 10 to break down lumber stack 12 into individual pieces of lumber 12a. Individual pieces of lumber 12a are transported away from breakdown hoist 10 on outfeed transfer chains 20. Outfeed transfer chains 20 are supported by an outfeed transfer frame (not shown).
Hydraulically actuated tilt arms 22 have lower arms 22a and upper arms 22b. Lower arms 22a and upper arms 22b form a rigid L-shaped cradle pivotally mounted about tilt arm pivot 24.
Tilt arms 22 may be hydraulically actuated by hydraulic ram 26 via linkage 28a and 28b so as to pivot tilt arms 22 about tilt arm pivot point 24. Tilt arms 22 may thereby be rotated between an upright position, wherein lower arms 22a are horizontal and upper arms 22b are vertical, and an inclined position, wherein upper arms 22b are, as illustrated in Figure 1, flush with face 14 and lower arms 22a protrude perpendicularly from face 14.
Infeed transfer frame 18 and infeed transfer chains 16 are arranged in proximity to breakdown hoist 10 so that the lumber engaging surfaces 16a of infeed transfer chains 16 are substantially aligned with the upper surfaces of lower arms 22a when tilt arms 22 are in the upright position. As illustrated in Figure 2, infeed transfer chains 16 may thus transfer lumber stack 12 onto lower arms 22a so as to abut lumber stack 12 against upper arms 22b when tilt arms 22 are in the upright position.
Once lumber stack 12 is transferred from infeed transfer chains 16 onto tilt arms 22, hydraulic ram 26 may be actuated to rotate rigid linkage arms 28a in direction "A" about axle 30 on transfer frame 18. Rotating rigid linkage arms 28a in direction "A" drives connecting rods 28b against lower arms 22a so as to rotate tilt arms 22 from the upright position illus-trated in Figure 2 to the inclined position illustrated in Figures 1 and 3. Hydraulic ram 26, rigid linkage arms 28a, and connecting rods 28b are pivotally connected at their ends. Axle 30 and tilt arm pivot 24 are mounted to the ends of longitudinal supporting members 18a extending from infeed transfer frame 18.
When tilt arms 22 and lumber stack 12 are in the inclined position, rotatable hoist arms 32 may be translated downwards along inclined supporting member 34 so as to position rotatable hoist arms 36 beneath tilt arms 22 as illustrated in Figure 3. Rotatable hoist arms 36 rotate about pins 38 on trolleys 40. Inclined supporting member 34 may be an I-beam or channel member and trolleys 40 may travel within the channel running the longitudinal length of the I-beam or channel member.
Trolleys 40 are translated downwards along inclined supporting member 34 until rotatable hoist arms 36 may be rotated in direction "B" from a position substantially parallel to face 14 to a position substantially perpendicular to face 14. Cables 42a and 42b, better seen in Figure 4, control the position of trolleys 40 along inclined supporting member 34. Cables 42a and 42b may be tensioned to snug rotatable hoist arms 36 against the underside of lumber stack 12 being supported by lower arms 22a.
That is, cables 42a and 42b may be tensioned to translate trolleys 40 upwards along inclined supporting member 34 thereby translating rotatable hoist arms 36 upwards against the underside of lumber stack 12. Cables 42 may be further tensioned to raise trolleys 40 upwards along inclined supporting member 34 thereby translating lumber stack 12 upwards along face 14.
As the upper tier of lumber stack 12 is raised past the top edge 14a of face 14, individual pieces of lumber 12a slide from lumber stack 12 along inclined discharge members 44.
Discharge members 44 extend substantially perpendicular from face 14 downwards from top edge 14a. Discharge members 44 discharge 2121~ Ql individual pieces of lumber 12a onto outfeed transfer chains 20 so that individual pieces of lumber 12a may be transported away from breakdown hoist 10 on outfeed transfer chains 20. Figure 2 illustrates this result. Rotatable hoist arms 36 have been rotated from their position illustrated in Figure 3 so as to be perpendicular to face 14 and then translated upwards along inclined supporting member 34 so as to engage and translate upwards lumber stack 12 thereby discharging individual pieces of lumber 12a from the tier of lumber stack 12 raised above top edge 14a.
As illustrated in Figure 4, rotatable hoist arms 36 are rigidly mounted to a transverse member 46 extending between trolleys 40. Transverse member 46 and rotatable hoist arms 36 may be rotated about pins 38 by hydraulic ram 48. Transverse member 46 rotates against stops 50, better illustrated in Figure 5. When transverse member 46 is rotated against stops 50, rotatable hoist arms 36 are substantially perpendicular to face 14.
Hydraulic cylinder 52 may be retracted to tension cables 42 thereby translating trolleys 40, transverse member 46 and rotating hoist arms 36 upwards along inclined supporting members 34. In particular, cable 42a is affixed at one end to transverse member 46, is threaded over single pulley 54, under tensioning pulley 56, over double pulleys 58 and is affixed at its distal end to upper transverse frame member 60. Cable 42b is affixed to the end of transverse member 46 opposite the end to which cable 42a is attached. Cable 42b is also threaded over double pulleys 58 and is affixed to the end of upper transverse frame member 60 to which is affixed cable 42a. Retraction or extension of hydraulic cylinder 52 respectively elevates or lowers trolleys 40, transverse member 46, and rotatable hoist arms 36 along inclined supporting members 34.
As illustrated in Figures 1 and 4, face 14 may be composed of parallel plates or sheeting supported by underframe ~121~t members 62. The parallel plates or sheeting forming face 14 are spaced apart so as to allow translation therebetween of rotatable hoist arms 36 and rotation of tilt arms 22. Face 14 serves to deflect sticks that might otherwise fall into supporting S underframe members 62. Sticks may thus be collected for re-use.
In operation, lumber stack 12 is transported by infeed transfer chains 16 onto tilt arms 22 when tilt arms 22 are in their upright position. Tilt arms 22, and lumber stack 12 supported thereon, are then rotated into an inclined position whereby lumber stack 12 is on its side flush against face 14.
Substantially simultaneously rotatable hoist arms 36 are rotated from a position substantially perpendicular to face 14 to a position substantially parallel to and beneath face 14 and then translated downwards by trolleys 40 so as to descend along inclined supporting members 34 beneath tilt arms 22 and lumber stack 12.
Once positioned beneath tilt arms 22 and lumber stack 12, rotatable hoist arms 36 are rotated back into a position substantially perpendicular to face 14 and translated upwards along inclined supporting members 34, by tensioning cables 42a and 42b, so as to engage rotatable hoist arms 36 against the bottom surface of lumber stack 12 resting in tilt arms 22. That is, when cables 42a and 42b are tensioned by cylinder 52, trolleys 40 are translated upwards along inclined supporting members 34 to thereby engage rotatable hoist arms 36 against the bottom surface of lumber stack 12. Upon further tensioning of cables 42a and 42b trolleys 40, transverse members 46 and rotatable hoist arms 36 are translated further upwards, thereby translating lumber stack 12 upwards by sliding lumber stack 12 over face 14.
As the top tier of lumber stack 12 is slid past top edge 14a on face 14, individual pieces of lumber 12a are discharged onto outfeed transfer chains 20 from inclined discharge members 44. As individual pieces of lumber 12a are discharged in this manner from lumber stack 12, a tier at a time, rotatable hoist arms 36 are translated further upwards along inclined supporting members 34.
Once hoist arms 36 have been translated upwards beyond the uppermost ends of upper arms 22b on tilt arms 22, tilt arms 22 are rotated back into their upright position ready to receive another lumber stack 12 from infeed transfer chains 16. Thus a cycle is established for the rapid breakdown of lumber stack 12.
Tilt arms 22 are receiving and inclining a second lumber stack 12 ready for upwards translation by rotatable hoist arms 36 while individual pieces of lumber 12a are being discharged from a first lumber stack 12 as the first lumber stack 12 is being translated upwards by rotatable hoist arms 36. Once the first lumber stack 12 has been completely discharged, sensors (not shown) or a sequence timer (not shown) or like cycle regulating machinery actuate the rotation of rotatable hoist arms 36 from their position perpendicular to face 14 to their position retracted beneath face 14 and rotatable hoist arms 36 are translated downwards for repositioning beneath the second stack of lumber 12 resting inclined against face 14 in tilt arms 22. Rotatable hoist arms 36 are, once positioned beneath the second stack of lumber 12 resting in tilt arms 22, rotated back into their extended position perpendicular to face 14 and translated upwards to thereby slide the second stack of lumber 12 upwards over face 14 to begin discharging individual pieces of lumber 12a from the second stack of lumber 12. Once the rotatable hoist arms 36 and the second stack of lumber 12 are clear of the uppermost ends of upper arms 22b on tilt arms 22, then tilt arms 22 are rotated back into their upright position ready to receive and incline a third lumber stack 12.
The cycle may be continuously repeated. The result of the timed or sequenced simultaneous co-operative movement of tile arms 22 and rotatable hoist arms 36 is an almost continuous breakdown of lumber stack 12 from breakdown hoist 10, only interrupted by the time it takes to reposition rotatable hoist 2121 lOl arms 36 beneath the next lumber stack 12 in tilt arms 22 and to slide that stack upwards over face 14 to top edge 14a.
As will be apparent to those skilled in the art in the light of the foregoing disclosure, many alterations and modifica-tions are possible in the practice of this invention without departing from the spirit or scope thereof. Accordingly, the scope of the invention is to be construed in accordance with the substance defined by the following claims.
A translatable hoist arm translates the stack of tiered material by sliding the stack upwards over the inclined face in a direction towards the upper edge of the inclined face. The hoist arm is rotatable between a recessed position, wherein it is recessed beneath the inclined face, and a stack translating position, wherein the hoist arm is substantially perpendicular to the inclined face. When in the stack translating position the hoist arm engages the underside of the stack of tiered material which has been inclined flush with the inclined face.
The stack of tiered material is translated over the inclined face towards the upper edge of the inclined face. The tiered material is thus deposited over the upper edge of the inclined face onto an outfeed transfer device such as an outfeed chain. The hoist arm is then rotated into its recessed position and translated downwards along the inclined surface so as to reposition beneath the stack receiving cradle ready to rotate into its stack translating position so as to translate the next stack of tiered material upwards over the inclined surface.
Brief Description of the Drawings Figure 1 is a perspective partial cut-away view of the tilt cradle breakdown hoist of the present invention.
Figure 2 is a left side elevation view of the present invention with tilt arms upright and hoist arms discharging lumber.
Figure 3 is a left side elevation view with tilt arms in an inclined position and hoist arms recessed and positioned beneath tilt arms.
Figure 4 is a partial cut-away front elevation view of the breakdown hoist of Figure 1.
Figure 5 is a detailed view of a portion of Figure 4.
2121~01 Detailed Description of the Preferred Embodiment As illustrated in Figure 1, breakdown hoist 10 is positioned for breaking down lumber stack 12 when delivered to face 14 of breakdown hoist 10 via infeed transfer chains 16 on infeed transfer frame 18. It is the purpose of breakdown hoist 10 to break down lumber stack 12 into individual pieces of lumber 12a. Individual pieces of lumber 12a are transported away from breakdown hoist 10 on outfeed transfer chains 20. Outfeed transfer chains 20 are supported by an outfeed transfer frame (not shown).
Hydraulically actuated tilt arms 22 have lower arms 22a and upper arms 22b. Lower arms 22a and upper arms 22b form a rigid L-shaped cradle pivotally mounted about tilt arm pivot 24.
Tilt arms 22 may be hydraulically actuated by hydraulic ram 26 via linkage 28a and 28b so as to pivot tilt arms 22 about tilt arm pivot point 24. Tilt arms 22 may thereby be rotated between an upright position, wherein lower arms 22a are horizontal and upper arms 22b are vertical, and an inclined position, wherein upper arms 22b are, as illustrated in Figure 1, flush with face 14 and lower arms 22a protrude perpendicularly from face 14.
Infeed transfer frame 18 and infeed transfer chains 16 are arranged in proximity to breakdown hoist 10 so that the lumber engaging surfaces 16a of infeed transfer chains 16 are substantially aligned with the upper surfaces of lower arms 22a when tilt arms 22 are in the upright position. As illustrated in Figure 2, infeed transfer chains 16 may thus transfer lumber stack 12 onto lower arms 22a so as to abut lumber stack 12 against upper arms 22b when tilt arms 22 are in the upright position.
Once lumber stack 12 is transferred from infeed transfer chains 16 onto tilt arms 22, hydraulic ram 26 may be actuated to rotate rigid linkage arms 28a in direction "A" about axle 30 on transfer frame 18. Rotating rigid linkage arms 28a in direction "A" drives connecting rods 28b against lower arms 22a so as to rotate tilt arms 22 from the upright position illus-trated in Figure 2 to the inclined position illustrated in Figures 1 and 3. Hydraulic ram 26, rigid linkage arms 28a, and connecting rods 28b are pivotally connected at their ends. Axle 30 and tilt arm pivot 24 are mounted to the ends of longitudinal supporting members 18a extending from infeed transfer frame 18.
When tilt arms 22 and lumber stack 12 are in the inclined position, rotatable hoist arms 32 may be translated downwards along inclined supporting member 34 so as to position rotatable hoist arms 36 beneath tilt arms 22 as illustrated in Figure 3. Rotatable hoist arms 36 rotate about pins 38 on trolleys 40. Inclined supporting member 34 may be an I-beam or channel member and trolleys 40 may travel within the channel running the longitudinal length of the I-beam or channel member.
Trolleys 40 are translated downwards along inclined supporting member 34 until rotatable hoist arms 36 may be rotated in direction "B" from a position substantially parallel to face 14 to a position substantially perpendicular to face 14. Cables 42a and 42b, better seen in Figure 4, control the position of trolleys 40 along inclined supporting member 34. Cables 42a and 42b may be tensioned to snug rotatable hoist arms 36 against the underside of lumber stack 12 being supported by lower arms 22a.
That is, cables 42a and 42b may be tensioned to translate trolleys 40 upwards along inclined supporting member 34 thereby translating rotatable hoist arms 36 upwards against the underside of lumber stack 12. Cables 42 may be further tensioned to raise trolleys 40 upwards along inclined supporting member 34 thereby translating lumber stack 12 upwards along face 14.
As the upper tier of lumber stack 12 is raised past the top edge 14a of face 14, individual pieces of lumber 12a slide from lumber stack 12 along inclined discharge members 44.
Discharge members 44 extend substantially perpendicular from face 14 downwards from top edge 14a. Discharge members 44 discharge 2121~ Ql individual pieces of lumber 12a onto outfeed transfer chains 20 so that individual pieces of lumber 12a may be transported away from breakdown hoist 10 on outfeed transfer chains 20. Figure 2 illustrates this result. Rotatable hoist arms 36 have been rotated from their position illustrated in Figure 3 so as to be perpendicular to face 14 and then translated upwards along inclined supporting member 34 so as to engage and translate upwards lumber stack 12 thereby discharging individual pieces of lumber 12a from the tier of lumber stack 12 raised above top edge 14a.
As illustrated in Figure 4, rotatable hoist arms 36 are rigidly mounted to a transverse member 46 extending between trolleys 40. Transverse member 46 and rotatable hoist arms 36 may be rotated about pins 38 by hydraulic ram 48. Transverse member 46 rotates against stops 50, better illustrated in Figure 5. When transverse member 46 is rotated against stops 50, rotatable hoist arms 36 are substantially perpendicular to face 14.
Hydraulic cylinder 52 may be retracted to tension cables 42 thereby translating trolleys 40, transverse member 46 and rotating hoist arms 36 upwards along inclined supporting members 34. In particular, cable 42a is affixed at one end to transverse member 46, is threaded over single pulley 54, under tensioning pulley 56, over double pulleys 58 and is affixed at its distal end to upper transverse frame member 60. Cable 42b is affixed to the end of transverse member 46 opposite the end to which cable 42a is attached. Cable 42b is also threaded over double pulleys 58 and is affixed to the end of upper transverse frame member 60 to which is affixed cable 42a. Retraction or extension of hydraulic cylinder 52 respectively elevates or lowers trolleys 40, transverse member 46, and rotatable hoist arms 36 along inclined supporting members 34.
As illustrated in Figures 1 and 4, face 14 may be composed of parallel plates or sheeting supported by underframe ~121~t members 62. The parallel plates or sheeting forming face 14 are spaced apart so as to allow translation therebetween of rotatable hoist arms 36 and rotation of tilt arms 22. Face 14 serves to deflect sticks that might otherwise fall into supporting S underframe members 62. Sticks may thus be collected for re-use.
In operation, lumber stack 12 is transported by infeed transfer chains 16 onto tilt arms 22 when tilt arms 22 are in their upright position. Tilt arms 22, and lumber stack 12 supported thereon, are then rotated into an inclined position whereby lumber stack 12 is on its side flush against face 14.
Substantially simultaneously rotatable hoist arms 36 are rotated from a position substantially perpendicular to face 14 to a position substantially parallel to and beneath face 14 and then translated downwards by trolleys 40 so as to descend along inclined supporting members 34 beneath tilt arms 22 and lumber stack 12.
Once positioned beneath tilt arms 22 and lumber stack 12, rotatable hoist arms 36 are rotated back into a position substantially perpendicular to face 14 and translated upwards along inclined supporting members 34, by tensioning cables 42a and 42b, so as to engage rotatable hoist arms 36 against the bottom surface of lumber stack 12 resting in tilt arms 22. That is, when cables 42a and 42b are tensioned by cylinder 52, trolleys 40 are translated upwards along inclined supporting members 34 to thereby engage rotatable hoist arms 36 against the bottom surface of lumber stack 12. Upon further tensioning of cables 42a and 42b trolleys 40, transverse members 46 and rotatable hoist arms 36 are translated further upwards, thereby translating lumber stack 12 upwards by sliding lumber stack 12 over face 14.
As the top tier of lumber stack 12 is slid past top edge 14a on face 14, individual pieces of lumber 12a are discharged onto outfeed transfer chains 20 from inclined discharge members 44. As individual pieces of lumber 12a are discharged in this manner from lumber stack 12, a tier at a time, rotatable hoist arms 36 are translated further upwards along inclined supporting members 34.
Once hoist arms 36 have been translated upwards beyond the uppermost ends of upper arms 22b on tilt arms 22, tilt arms 22 are rotated back into their upright position ready to receive another lumber stack 12 from infeed transfer chains 16. Thus a cycle is established for the rapid breakdown of lumber stack 12.
Tilt arms 22 are receiving and inclining a second lumber stack 12 ready for upwards translation by rotatable hoist arms 36 while individual pieces of lumber 12a are being discharged from a first lumber stack 12 as the first lumber stack 12 is being translated upwards by rotatable hoist arms 36. Once the first lumber stack 12 has been completely discharged, sensors (not shown) or a sequence timer (not shown) or like cycle regulating machinery actuate the rotation of rotatable hoist arms 36 from their position perpendicular to face 14 to their position retracted beneath face 14 and rotatable hoist arms 36 are translated downwards for repositioning beneath the second stack of lumber 12 resting inclined against face 14 in tilt arms 22. Rotatable hoist arms 36 are, once positioned beneath the second stack of lumber 12 resting in tilt arms 22, rotated back into their extended position perpendicular to face 14 and translated upwards to thereby slide the second stack of lumber 12 upwards over face 14 to begin discharging individual pieces of lumber 12a from the second stack of lumber 12. Once the rotatable hoist arms 36 and the second stack of lumber 12 are clear of the uppermost ends of upper arms 22b on tilt arms 22, then tilt arms 22 are rotated back into their upright position ready to receive and incline a third lumber stack 12.
The cycle may be continuously repeated. The result of the timed or sequenced simultaneous co-operative movement of tile arms 22 and rotatable hoist arms 36 is an almost continuous breakdown of lumber stack 12 from breakdown hoist 10, only interrupted by the time it takes to reposition rotatable hoist 2121 lOl arms 36 beneath the next lumber stack 12 in tilt arms 22 and to slide that stack upwards over face 14 to top edge 14a.
As will be apparent to those skilled in the art in the light of the foregoing disclosure, many alterations and modifica-tions are possible in the practice of this invention without departing from the spirit or scope thereof. Accordingly, the scope of the invention is to be construed in accordance with the substance defined by the following claims.
Claims (10)
1. A breakdown hoist for breaking down a stack of tiered material comprises an inclined face having upper and lower edges, said stack of tiered material translatable over said inclined face between said upper and lower edges, a supporting frame supporting said inclined face, a rotatable stack receiving cradle for receiving said stack of tiered material from a stack transfer device and rotating said stack of tiered material into slidable engagement with said inclined face, a translatable hoist arm translatable along said inclined face for translating said stack of tiered material between said upper edge and said lower edge in a direction towards said upper edge on said inclined face, and means for translating said translatable hoist arm along said inclined face, said translatable hoist arm rotatable between a recessed position recessed beneath said inclined face and a stack translating position substantially perpendicular to said inclined face, whereby when in said stack translating position said translatable hoist arm may engage an underside surface of said stack of tiered material and slide said stack of tiered material over said inclined face towards said upper edge of said inclined face so as to deposit said tiered material over said upper edge.
2. The device of Claim 1 wherein said inclined face comprises a plurality of spaced apart inclined mem-bers, said rotatable stack receiving cradle comprises a plurality of spaced apart support arms, said support arms staggered relative to said inclined members so as to position said support arms between said inclined members, and said translatable hoist arm comprises a plurality of spaced apart hoist arms, said plurality of spaced apart hoist arms staggered relative to said inclined members and said support arms so as to posi-tion said hoist arms between said inclined members and said support arms, whereby said hoist arms are translatable along substantially the length of said inclined members past said support arms.
3. The device of Claim 2 wherein said plurality of spaced apart inclined members have a first inclined member of said plurality of spaced apart inclined members and a last inclined member of said plurality of spaced apart inclined members, said first inclined member and said last inclined member at opposed ends of said plurality of spaced apart inclined members, wherein said first inclined member is supported by a first inclined support member and said last inclined member is supported by a last inclined support member and said hoist arms are translatable between said upper and lower edges of said inclined face on a transverse supporting member translatably supported at its ends on said first and last inclined support members.
4. The device of Claim 3 wherein said transverse supporting member is rotatably mounted to means for translating said transverse supporting member along said inclined support members and said transverse support member rigidly supports said hoist arms in parallel spaced apart array.
5. The device of Claim 4 wherein said means for translating said transverse support member along said inclined support members comprises an opposed pair of wheeled trolleys and said inclined support members comprise members each having a longitudinal channel, whereby said opposed pair of wheeled trolleys are translatable along said longitudinal channels and said means for translating said transverse supporting member along said inclined support members comprises retractable flexible cables attached to said trolleys, retractable so as to position said trolleys along said inclined support members.
6. The device of Claim 5 wherein said support arms comprise rigid "L"-shaped arms having intersecting substantially perpendicular upper and lower arms, said "L"-shaped arms pivotable about the intersection of said upper and lower arms so as to be rotatable between an upright position and an inclined position whereby when in said upright position said stack of tiered material may be transferred onto said lower arms in snug abutment with said upper arms, and when in said inclined position said stack of tiered material is rotated so as to rest one side of said stack of tiered material flush along said inclined face.
7. The device of Claim 6 wherein when said hoist arms are rotated into said recessed position, said hoist arms may be translated to a position underneath said stack of tiered material when said stack of tiered material is supported by said "L"-shaped arms in said inclined position, whereby said hoist arms may be rotated from said recessed position to said stack translating position and said cables retracted so as to urge said hoist arms against said stack of tiered material to thereby translate said stack of tiered material over said inclined face towards said upper edge.
8. The device of Claim 7 further comprising sensing means for sensing when said stack of tiered material has been deposited over said upper edge, said sensing means, once said stack of tiered material has been deposited over said upper edge, communicating with said hoist arms so as to trigger said rotation of said hoist arms into said recessed position and so as to trigger translation of said hoist arms downwards to reposition said hoist arms beneath a second stack of tiered material in said support arms.
9. The device of Claim 8 wherein said sensing means further communicates with means for detensioning said cables whereby when said stack of tiered material has been deposited over said upper edge, said sensing means communicates with said means for detensioning said cables and said means for detensioning said cables detensions said cables so as to translate said hoist arms in said recessed position downwards to position said hoist arms beneath said support arms and said second stack of lumber supported therein.
10. A method of breaking down a stack of tiered material using a breakdown hoist having an inclined face having upper and lower edges, a supporting frame supporting said inclined face, a rotatable stack receiving cradle for receiving said stack of tiered material from a stack transfer device, a translatable hoist arm translatable along said inclined face, and means for translating said translatable hoist arm along said inclined face, said translatable hoist arm rotatable between a recessed position recessed beneath said inclined face and a stack translating position substantially perpendicular to said inclined face comprising the steps of:
(a) depositing said stack of tiered material from said stack translating device onto said rotatable stack receiving cradle, (b) rotating said stack of tiered material and said rotatable stack receiving cradle so as to rotate said stack of tiered material into slidable engagement with said inclined face, (c) rotating said translatable hoist arm into said recessed position and translating said translatable hoist arm downwards along said inclined face to a position beneath said stack of tiered material and said rotatable stack receiv-ing cradle, (d) rotating said translatable hoist arm from said recessed position to said stack translating position, (e) translating said hoist arm in said stack translating position upwards along said inclined face so as to urge said stack of tiered material out of said rotatable stack receiving cradle and upwards over said inclined face towards said upper edge on said inclined face, (f) rotating said rotatable stack receiving cradle from said inclined position back into said upright position and depositing onto said rotatable stack receiving cradle a second stack of tiered material from said stack transfer device, (g) translating said translatable hoist arm and said stack of tiered material upwards over said inclined face so as to deposit said tiered material over said upper edge on said inclined face, (h) rotating said translatable hoist arm into said recessed position and translating said translat-able hoist arm downwards along said inclined face to said position beneath said rotatable stack receiving cradle so as to reposition said trans-latable hoist arm beneath said second stack of tiered material once all of said tiered material have been deposited over said upper edge of said inclined face.
(a) depositing said stack of tiered material from said stack translating device onto said rotatable stack receiving cradle, (b) rotating said stack of tiered material and said rotatable stack receiving cradle so as to rotate said stack of tiered material into slidable engagement with said inclined face, (c) rotating said translatable hoist arm into said recessed position and translating said translatable hoist arm downwards along said inclined face to a position beneath said stack of tiered material and said rotatable stack receiv-ing cradle, (d) rotating said translatable hoist arm from said recessed position to said stack translating position, (e) translating said hoist arm in said stack translating position upwards along said inclined face so as to urge said stack of tiered material out of said rotatable stack receiving cradle and upwards over said inclined face towards said upper edge on said inclined face, (f) rotating said rotatable stack receiving cradle from said inclined position back into said upright position and depositing onto said rotatable stack receiving cradle a second stack of tiered material from said stack transfer device, (g) translating said translatable hoist arm and said stack of tiered material upwards over said inclined face so as to deposit said tiered material over said upper edge on said inclined face, (h) rotating said translatable hoist arm into said recessed position and translating said translat-able hoist arm downwards along said inclined face to said position beneath said rotatable stack receiving cradle so as to reposition said trans-latable hoist arm beneath said second stack of tiered material once all of said tiered material have been deposited over said upper edge of said inclined face.
Priority Applications (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA 2121401 CA2121401C (en) | 1994-04-15 | 1994-04-15 | Tilt cradle breakdown hoist |
| PCT/CA1995/000210 WO1995028344A1 (en) | 1994-04-15 | 1995-04-13 | Tilt cradle breakdown hoist |
| AU22116/95A AU2211695A (en) | 1994-04-15 | 1995-04-13 | Tilt cradle breakdown hoist |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA 2121401 CA2121401C (en) | 1994-04-15 | 1994-04-15 | Tilt cradle breakdown hoist |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CA2121401A1 CA2121401A1 (en) | 1995-10-16 |
| CA2121401C true CA2121401C (en) | 1997-12-09 |
Family
ID=4153390
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA 2121401 Expired - Fee Related CA2121401C (en) | 1994-04-15 | 1994-04-15 | Tilt cradle breakdown hoist |
Country Status (3)
| Country | Link |
|---|---|
| AU (1) | AU2211695A (en) |
| CA (1) | CA2121401C (en) |
| WO (1) | WO1995028344A1 (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7740440B2 (en) | 2007-09-20 | 2010-06-22 | Mill Tech Industries | Continuous breakdown hoists |
| CA3060524C (en) * | 2018-10-29 | 2022-04-12 | Usnr, Llc | Tilt hoists and lumber unstacking systems |
| CN116331855B (en) * | 2023-04-11 | 2023-09-15 | 安徽中兴造船有限公司 | Push type steel plate automatic feeding device of shipyard butt joint steel plate conveying line |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3565266A (en) * | 1968-09-17 | 1971-02-23 | Buss Automation Inc | Lumber breakdown hoist |
| DE2152727C3 (en) * | 1971-10-22 | 1975-11-20 | Karl Haist Kg, 8000 Muenchen | Device for automatic unstacking and feeding of boards to a processing machine |
-
1994
- 1994-04-15 CA CA 2121401 patent/CA2121401C/en not_active Expired - Fee Related
-
1995
- 1995-04-13 WO PCT/CA1995/000210 patent/WO1995028344A1/en active Application Filing
- 1995-04-13 AU AU22116/95A patent/AU2211695A/en not_active Abandoned
Also Published As
| Publication number | Publication date |
|---|---|
| AU2211695A (en) | 1995-11-10 |
| CA2121401A1 (en) | 1995-10-16 |
| WO1995028344A1 (en) | 1995-10-26 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CA1298326C (en) | Pallet loading apparatus | |
| US4067456A (en) | Apparatus for arranging and stacking nonrigid articles | |
| US4902195A (en) | Device for automatically piling up flat elements | |
| US6561752B2 (en) | Pallet and top frame handler for a palletizer and method of handling a pallet and top frame in a palletizer | |
| US4610360A (en) | Installation for stacking piles of lumber separated by sticks | |
| US5890579A (en) | Apparatus for separating and dealing individual boards from an uninterrupted mat of boards to a conveyor | |
| CA2230464C (en) | Continuous breakdown tilt hoist with overhead rotatable secondary hoist | |
| CA2208385A1 (en) | Cart loader and method of loading | |
| US5435690A (en) | Method and apparatus for loading layers of articles | |
| US5271334A (en) | Cart loading equipment having reciprocating pusher and chain conveyors with sensor operated central control | |
| CA2121401C (en) | Tilt cradle breakdown hoist | |
| US5385117A (en) | Poultry collection device | |
| US4229133A (en) | Lumber spacer and stick layer | |
| US4632633A (en) | Apparatus for loading cylindrical articles onto pallets | |
| CA2215460C (en) | Sticker placing mechanism for use with lumber stacker | |
| CA2211384C (en) | Method and apparatus for high speed variable tier width lumber stacking | |
| US4516900A (en) | De-palletizer | |
| US5795126A (en) | Tilt hoist with multiple independent rotatable masts | |
| US5350272A (en) | Automatic stick laying apparatus | |
| CA1121837A (en) | Lumber stacker and method | |
| US2838185A (en) | Loading device | |
| US4051958A (en) | Pallet unloading and orienting device | |
| US5707204A (en) | Stacking apparatus | |
| US4417836A (en) | Device for separating a stack by layers, particularly a stack of long timbers or lumber | |
| WO1993007080A1 (en) | Cart loading machine |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| EEER | Examination request | ||
| MKLA | Lapsed |