WO2002071833A1 - An apparatus for cutting a tree trunk - Google Patents

An apparatus for cutting a tree trunk Download PDF

Info

Publication number
WO2002071833A1
WO2002071833A1 PCT/SE2002/000424 SE0200424W WO02071833A1 WO 2002071833 A1 WO2002071833 A1 WO 2002071833A1 SE 0200424 W SE0200424 W SE 0200424W WO 02071833 A1 WO02071833 A1 WO 02071833A1
Authority
WO
WIPO (PCT)
Prior art keywords
guard
saw
cutting
swingable
inoperative position
Prior art date
Application number
PCT/SE2002/000424
Other languages
French (fr)
Inventor
Sten NYSTRÖM
Original Assignee
Partek Forest Ab
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Partek Forest Ab filed Critical Partek Forest Ab
Publication of WO2002071833A1 publication Critical patent/WO2002071833A1/en

Links

Classifications

    • A—HUMAN NECESSITIES
    • A01—AGRICULTURE; FORESTRY; ANIMAL HUSBANDRY; HUNTING; TRAPPING; FISHING
    • A01G—HORTICULTURE; CULTIVATION OF VEGETABLES, FLOWERS, RICE, FRUIT, VINES, HOPS OR SEAWEED; FORESTRY; WATERING
    • A01G23/00—Forestry
    • A01G23/02—Transplanting, uprooting, felling or delimbing trees
    • A01G23/08—Felling trees
    • A01G23/091—Sawing apparatus specially adapted for felling trees

Definitions

  • This invention relates to a unit arranged to be carried by an arm on a forestry vehicle, comprising gripping means for gripping and lifting tree trunks and a chain saw that is suspended to be swingable by a motor into an inoperative swung-back position in a shield and swingable from its inoperative position to a position for cutting a gripped and lifted tree trunk.
  • Single-grip harvesters are used to grip a tree trunk close to the ground and cut it off, lift it to horizontal position without changing grip and then strip the trunk of branches and cut the trunk into logs.
  • Figure 1 is a side view of a wheeled forestry machine, a harvester, with a single grip harvester head in accordance with the invention.
  • Figure 2 is a side view on a larger scale of the single grip harvester head shown in figure 1.
  • Figure 3 is a front end view of a the single grip harvester head shown in figures 1 and 2.
  • Figure 4 is a top view of the single grip harvester head shown in figures 1-3.
  • Figure 5 is a perspective view of a cutting unit that is part of the single grip harvester head.
  • Figure 6 is a perspective view corresponding to figure 4 but showing some elements in other positions.
  • Figure 7 is a perspective view of a grapple saw in accordance with the invention.
  • Figure 1 shows schematically a harvester with a wheeled vehicle 11 that carries a crane 12,13 with a boom 12 that is swingable about a vertical axis.
  • the boom carries an axially displaceable stick 13 which in its turn carries a single grip harvester head 14 that is rotatable in a rotator 15 and also tiltable.
  • the rotator is freely suspended in the stick 13 but it is not turnable.
  • the operator in the cabin 16 can move the head into all positions within the reach of the crane and control all the functions of the head, but the means for this is not illustrated in detail since they are conventional.
  • Figure 2 shows the head 14 on a larger scale and in more detail. It is suspended in a tilt link 20 which is suspended in the rotator 15 and the head can be tilted about a shaft 21. In the figures, the head is shown in it position for felling.
  • FIG. 4 At the lower end of the head 14, there is a cutting unit 22 that is shown in the perspective views, figures 4 and 5.
  • a chain saw 23 with a saw bar 24 is mounted in the cutting unit and it is swingable out of the cutting unit by being swung about an axis I by means of a turning motor 25 coaxial with the axis.
  • the saw bar 24 In figure 4, the saw bar 24 is shown in its position in which it is swung into the cutting unit where it is protected by a protecting plate 26, and in figure 5, the saw bar is shown in its position in which it is swung out of the cutting unit as during a cutting operation.
  • An elongated guard 30 of an elastically yieldable material, for example thick reinforced rubber, is suspended to be swingable about an axis II that is parallel with the swing axis of the saw. Its mounting is just in front of the tip of the saw bar when the saw is in its inoperative position.
  • a similar but shorter guard 31 is mounted in the same way behind the saw to be swingable about an axis III that is also parallel with the swing axis of the saw.
  • the guards are swingable by concentric turning motors and the motor 32 for swinging the short guard 31 can be seen in figures 4 and 5.
  • the two guards 30 and 31 are not shown in figures 2 and 3.
  • the two guards 30 and 31 are shown swung back into their inoperative positions and in figure 6 they are shown in their operative positions.
  • the guard 30 is swung out when in its operative position so that it is directed transverse to the saw bar, and the saw bar will then be directed towards the guard during its entire swinging out movement in a cutting operation so that the guard will catch the saw chain should the chain break and be thrown away from the saw bar.
  • the guard is long enough to cover the saw bar also when the saw bar is fully swung out.
  • the head has two feeding wheels 35,36 that are mounted to be swingable.
  • FIGS 2 and 3 they are shown in their positions moved apart, but in their operative positions, they are loaded towards each other in order to clamp a tree trunk between them.
  • the head has an upper two-part branching knife 37a and 37b, a lower two-part branching knife 38a and 38b, and a counting wheel 39.
  • the branching knives are shown in their open positions. In their closed positions, they guide the trunk without preventing it from being forwarded by the feeding wheels 35,36.
  • the head is moved towards the bottom part of the tree that is to be felled.
  • the feeding wheels 35,36 and the branch knives 37,38 are open and swung inwards when the head embraces the tree.
  • the chain saw 23 With its guards 30,31 in their inoperative positions, the chain saw 23 is swung out and cuts the trunk while the trunk is firmly held by the feeding wheels and the branch knives.
  • the head is lifted by the crane 12,13 and swung in the tilt link 20 so that the tree trunk will be substantially horizontal with its top dragging along the ground. In this suspended position, the tree trunk is moved forwards by the feeding wheels and the branch knives prevent the trunk from falling out of the head.
  • the counting wheel 39 is coupled to stop the feeding motion when a predefined length of the tree trunk has been moved forwards.
  • the branch knives 37,38 strips off the branches during this movement.
  • the guards 31,32 are swung out into their operative positions as shown in figure 5, and the chain saw 23 is swung out cutting off the trunk.
  • the guards are then swung back into their inoperative positions shown in figure 4.
  • the trunk is again cut off in the same way with the guards in their swung-out positions and this operation is continued until the trunk is cut into logs of predefined length.
  • guards 30,31 are swung into their protected inoperative positions after every so called free-hanging cutting, there is no risk that they will be destroyed by branches during the branch-stripping operation.
  • the fact that the guards are not rigid but are yieldable reduces the risk of damage further. Neither are the guards in the way nor can they be damaged during the felling since they are then in their protected positions. The saw is close to the ground during the felling and a guard is not necessary then since the chain will soon be stopped by the ground if it should break. Since the guards are long and elastically yieldable, they will dampen a thrown-out chain better than a stiff guard.
  • the guards can suitably be made of reinforced rubber and be more than 3 cm thick.
  • Figure 6 shows a conventional grapple saw head by which a bundle of thin trunks can be gripped and in such a free-hanging position cut in a single cutting operation.
  • the grapple saw head has a rotator 15 by which it can be suspended in a crane in the same way as the harvester head shown suspended in figure 1.
  • the grapple saw head has two gripper claws 42 and a gripper claw 41 opposite the claws 42. It has also a cutting unit 43 with a guard 30, arranged in the same way as in the figures 4 and 5, and a saw bar as in the previous figures.
  • the saw bar denoted by 24. Since the guard can be swung in as described, it will not be in the way neither during the gripping nor when the grapple saw is used for loading instead of for cutting.

Landscapes

  • Life Sciences & Earth Sciences (AREA)
  • Biodiversity & Conservation Biology (AREA)
  • Ecology (AREA)
  • Forests & Forestry (AREA)
  • Environmental Sciences (AREA)
  • Shovels (AREA)
  • Harvesting Machines For Specific Crops (AREA)
  • Harvester Elements (AREA)
  • Catching Or Destruction (AREA)

Abstract

A single grip harvester head (14) has a chain saw (23) that is mounted to be svingable by a motor (25) into an inoperative position in a shield (26) and swingable out of the inoperative position for cutting a gripped and lifted tree trunk. A guard (30) is mounted to be swingable such that its mounting is adjacent the free end of the saw bar (24) when the saw (23) is in its inoperative position. The axes of swinging of the saw and the guard are parallel and the guard is swingale between an operative position in which it is transverse to the saw bar and a retracted inoperative position. The guard is used during a cutting operation with the tree trunk suspended but it is retracted during felling.

Description

An apparatus for cutting a tree trunk
Technichal field of the invention
This invention relates to a unit arranged to be carried by an arm on a forestry vehicle, comprising gripping means for gripping and lifting tree trunks and a chain saw that is suspended to be swingable by a motor into an inoperative swung-back position in a shield and swingable from its inoperative position to a position for cutting a gripped and lifted tree trunk.
Background of the invention
Single-grip harvesters are used to grip a tree trunk close to the ground and cut it off, lift it to horizontal position without changing grip and then strip the trunk of branches and cut the trunk into logs.
In such a cutting with the tree trunk in a suspended position, one wants a higher cutting power than used for felling only. Since the tree trunk has a free-hanging end during the cutting, the cutting must be fast in order to avoid cracks at the end of the cutting. The high cutting power is reached by a higher speed of the chain, which increases the stress on the chain and results in increased risk of chain breakage. The high velocity throws away the chain at a high velocity if the chain breaks and is a risk to the driver also when the driver is in a cabin, and it is of course also a risk to a third person.
There is the same risk when felling heads are used that fell and cut into logs but do not strip off the branches and at grapple saw heads that lifts a bundle of thin trunks and cuts the entire bundle.
Object of invention
It is an object of the invent ion to reduce the risk of injuring people when forestry units of the kind described above are used. Principally, this is achieved with a guard suspended swingably such that its mounting end is adjacent the free end of the saw bar when the saw is in its inoperative position, wherein the swing axes of the of the saw and the guard are parallel and the guard is swingable between an operative position in which it is directed transverse to the chain bar and a swung-back inoperative position. The invention is defined by the claims Brief description of the drawings
The drawings show two units as examples of the invention.
• Figure 1 is a side view of a wheeled forestry machine, a harvester, with a single grip harvester head in accordance with the invention.
• Figure 2 is a side view on a larger scale of the single grip harvester head shown in figure 1.
• Figure 3 is a front end view of a the single grip harvester head shown in figures 1 and 2.
• Figure 4 is a top view of the single grip harvester head shown in figures 1-3.
• Figure 5 is a perspective view of a cutting unit that is part of the single grip harvester head.
• Figure 6 is a perspective view corresponding to figure 4 but showing some elements in other positions.
• Figure 7 is a perspective view of a grapple saw in accordance with the invention.
Description in more detail of the illustrated examples of the invention
Figure 1 shows schematically a harvester with a wheeled vehicle 11 that carries a crane 12,13 with a boom 12 that is swingable about a vertical axis. The boom carries an axially displaceable stick 13 which in its turn carries a single grip harvester head 14 that is rotatable in a rotator 15 and also tiltable. The rotator is freely suspended in the stick 13 but it is not turnable. The operator in the cabin 16 can move the head into all positions within the reach of the crane and control all the functions of the head, but the means for this is not illustrated in detail since they are conventional. Figure 2 shows the head 14 on a larger scale and in more detail. It is suspended in a tilt link 20 which is suspended in the rotator 15 and the head can be tilted about a shaft 21. In the figures, the head is shown in it position for felling.
At the lower end of the head 14, there is a cutting unit 22 that is shown in the perspective views, figures 4 and 5. A chain saw 23 with a saw bar 24 is mounted in the cutting unit and it is swingable out of the cutting unit by being swung about an axis I by means of a turning motor 25 coaxial with the axis. In figure 4, the saw bar 24 is shown in its position in which it is swung into the cutting unit where it is protected by a protecting plate 26, and in figure 5, the saw bar is shown in its position in which it is swung out of the cutting unit as during a cutting operation.
An elongated guard 30 of an elastically yieldable material, for example thick reinforced rubber, is suspended to be swingable about an axis II that is parallel with the swing axis of the saw. Its mounting is just in front of the tip of the saw bar when the saw is in its inoperative position. A similar but shorter guard 31 is mounted in the same way behind the saw to be swingable about an axis III that is also parallel with the swing axis of the saw. The guards are swingable by concentric turning motors and the motor 32 for swinging the short guard 31 can be seen in figures 4 and 5. The two guards 30 and 31 are not shown in figures 2 and 3.
In figure 5, the two guards 30 and 31 are shown swung back into their inoperative positions and in figure 6 they are shown in their operative positions. The guard 30 is swung out when in its operative position so that it is directed transverse to the saw bar, and the saw bar will then be directed towards the guard during its entire swinging out movement in a cutting operation so that the guard will catch the saw chain should the chain break and be thrown away from the saw bar. The guard is long enough to cover the saw bar also when the saw bar is fully swung out.
In the conventional way, the head has two feeding wheels 35,36 that are mounted to be swingable. In figures 2 and 3, they are shown in their positions moved apart, but in their operative positions, they are loaded towards each other in order to clamp a tree trunk between them. The head has an upper two-part branching knife 37a and 37b, a lower two-part branching knife 38a and 38b, and a counting wheel 39. The branching knives are shown in their open positions. In their closed positions, they guide the trunk without preventing it from being forwarded by the feeding wheels 35,36.
A working operation will now be described
The head is moved towards the bottom part of the tree that is to be felled. The feeding wheels 35,36 and the branch knives 37,38 are open and swung inwards when the head embraces the tree. With its guards 30,31 in their inoperative positions, the chain saw 23 is swung out and cuts the trunk while the trunk is firmly held by the feeding wheels and the branch knives. After the cutting, the head is lifted by the crane 12,13 and swung in the tilt link 20 so that the tree trunk will be substantially horizontal with its top dragging along the ground. In this suspended position, the tree trunk is moved forwards by the feeding wheels and the branch knives prevent the trunk from falling out of the head. The counting wheel 39 is coupled to stop the feeding motion when a predefined length of the tree trunk has been moved forwards. The branch knives 37,38 strips off the branches during this movement. The guards 31,32 are swung out into their operative positions as shown in figure 5, and the chain saw 23 is swung out cutting off the trunk. The guards are then swung back into their inoperative positions shown in figure 4. After another feeding movement, the trunk is again cut off in the same way with the guards in their swung-out positions and this operation is continued until the trunk is cut into logs of predefined length.
Since the guards 30,31 are swung into their protected inoperative positions after every so called free-hanging cutting, there is no risk that they will be destroyed by branches during the branch-stripping operation. The fact that the guards are not rigid but are yieldable reduces the risk of damage further. Neither are the guards in the way nor can they be damaged during the felling since they are then in their protected positions. The saw is close to the ground during the felling and a guard is not necessary then since the chain will soon be stopped by the ground if it should break. Since the guards are long and elastically yieldable, they will dampen a thrown-out chain better than a stiff guard. The guards can suitably be made of reinforced rubber and be more than 3 cm thick.
Figure 6 shows a conventional grapple saw head by which a bundle of thin trunks can be gripped and in such a free-hanging position cut in a single cutting operation. The grapple saw head has a rotator 15 by which it can be suspended in a crane in the same way as the harvester head shown suspended in figure 1. The grapple saw head has two gripper claws 42 and a gripper claw 41 opposite the claws 42. It has also a cutting unit 43 with a guard 30, arranged in the same way as in the figures 4 and 5, and a saw bar as in the previous figures. The saw bar denoted by 24. Since the guard can be swung in as described, it will not be in the way neither during the gripping nor when the grapple saw is used for loading instead of for cutting.

Claims

Claims
1. A unit arranged to be carried by an arm (12,13) on a forestry vehicle (11), comprising gripping means (35,36; 41,42) for gripping and lifting tree trunks and a chain saw (23) that is suspended to be swingable by a motor (25) into an inoperative swung-back position in a shield (26) and swingable from its inoperative position to a position for cutting a gripped and lifted tree trunk, characterised by a guard (30) suspended swingably such that its mounting end is adjacent the free end of the chain bar (24) when the saw (23) is in its inoperative position, wherein the swing axes of the of the saw and the guard are parallel and the guard is swingable between an operative position in which it is directed transverse to the chain bar and a swung-back inoperative position.
2. A unit according to claim 1, characterised in that it is a single-grip harvester head with two feeding wheels (35,36), which are biased against each other but can be moved away from each other, and two branch cutters (37,38), which can be opened.
3. A unit according to claim 2, characterised in that the guard (30) consists of an elastically yieldable material.
4. A unit according to claim 3, characterised in that the guard (30) consists of reinforced rubber.
PCT/SE2002/000424 2001-03-09 2002-03-08 An apparatus for cutting a tree trunk WO2002071833A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
SE0100837A SE0100837L (en) 2001-03-09 2001-03-09 Aggregate for cutting a tree trunk
SE0100837-4 2001-03-09

Publications (1)

Publication Number Publication Date
WO2002071833A1 true WO2002071833A1 (en) 2002-09-19

Family

ID=20283306

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/SE2002/000424 WO2002071833A1 (en) 2001-03-09 2002-03-08 An apparatus for cutting a tree trunk

Country Status (2)

Country Link
SE (1) SE0100837L (en)
WO (1) WO2002071833A1 (en)

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP2104599A1 (en) * 2007-01-18 2009-09-30 Log Max AB Arrangement for the capture of a broken sawchain
US7690407B2 (en) 2002-07-12 2010-04-06 John Deere Forestry Oy Sawing device and its safety system for precaution of a breaking saw chain
AU2011200196B2 (en) * 2010-11-30 2012-07-26 A W Trinder Limited Tree Felling And Grappling Head
US20150314470A1 (en) * 2012-12-13 2015-11-05 Komatsu Forest Ab Arrangement for the passive capture of a broken saw chain
US9439363B1 (en) 2015-04-27 2016-09-13 Caterpillar Forest Products Inc. Bracket system for grapple assembly
US9795091B2 (en) 2013-03-18 2017-10-24 A W Trinder Limited Tree felling and grappling head

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FI118248B (en) * 2003-12-22 2007-09-14 Ponsse Oyj Arrangement at a cutting saw in a harvester

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4991297A (en) * 1989-09-18 1991-02-12 Cain Myron C Safety guard for chain saw bar
US5850696A (en) * 1996-09-09 1998-12-22 Sciarrone; Angelo Chain saw guard

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4991297A (en) * 1989-09-18 1991-02-12 Cain Myron C Safety guard for chain saw bar
US5850696A (en) * 1996-09-09 1998-12-22 Sciarrone; Angelo Chain saw guard

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7690407B2 (en) 2002-07-12 2010-04-06 John Deere Forestry Oy Sawing device and its safety system for precaution of a breaking saw chain
EP2104599A1 (en) * 2007-01-18 2009-09-30 Log Max AB Arrangement for the capture of a broken sawchain
EP2104599A4 (en) * 2007-01-18 2013-06-05 Log Max Ab Arrangement for the capture of a broken sawchain
AU2008205698B2 (en) * 2007-01-18 2013-06-27 Log Max Ab Arrangement for the capture of a broken sawchain
US8499463B2 (en) 2007-01-18 2013-08-06 Log Max Ab Saw box for preventing chain shot from a broken sawchain
AU2011200196B2 (en) * 2010-11-30 2012-07-26 A W Trinder Limited Tree Felling And Grappling Head
AU2011200196C1 (en) * 2010-11-30 2018-10-11 A W Trinder Limited Tree Felling And Grappling Head
US20150314470A1 (en) * 2012-12-13 2015-11-05 Komatsu Forest Ab Arrangement for the passive capture of a broken saw chain
US9656406B2 (en) 2012-12-13 2017-05-23 Komatsu Forest Ab Arrangement for the passive capture of a broken saw chain
US9795091B2 (en) 2013-03-18 2017-10-24 A W Trinder Limited Tree felling and grappling head
US9439363B1 (en) 2015-04-27 2016-09-13 Caterpillar Forest Products Inc. Bracket system for grapple assembly

Also Published As

Publication number Publication date
SE517665C2 (en) 2002-07-02
SE0100837L (en) 2002-07-02
SE0100837D0 (en) 2001-03-09

Similar Documents

Publication Publication Date Title
US6135175A (en) Tree harvester provided with a rotatable worktable
US5785101A (en) Tree harvesting and processing head
US9795091B2 (en) Tree felling and grappling head
AU2011200196C1 (en) Tree Felling And Grappling Head
FI74382C (en) Device for tree felling.
US7373960B1 (en) Brush cutter
SE467233B (en) Aggregate for forest logging machine
US5628354A (en) Tree processor attachment for log porters
WO2002071833A1 (en) An apparatus for cutting a tree trunk
US4382457A (en) Tree harvester
US4779654A (en) Tree harvesting
US4412777A (en) Device for a felling and gripping unit
CA2627845C (en) Tree chipper
US6418989B1 (en) Standing-stem timber harvesting system
EP2804468B1 (en) Cutting arrangement for gripping and cutting trees or bushes
EP0041515B1 (en) Tree harvester
US4127154A (en) Tree harvesting apparatus
US6371177B1 (en) Tree delimbing head for boom-type delimbers
CA1214976A (en) Tree felling apparatus
US5445197A (en) Arrangement in tree-processing assembly
CA2173634C (en) Tree harvester provided with a ratatable worktable
RU2815346C1 (en) Method of felling trees during winter logging
USRE30153E (en) Tree harvester
FI88853B (en) Method and device for forest thinning
CA2800448C (en) Tree felling and grappling head

Legal Events

Date Code Title Description
AK Designated states

Kind code of ref document: A1

Designated state(s): AE AG AL AM AT AU AZ BA BB BG BR BY BZ CA CH CN CO CR CU CZ DE DK DM DZ EE ES FI GB GD GE GH GM HR HU ID IL IN IS JP KE KG KP KR KZ LC LK LR LS LT LU LV MA MD MG MK MN MW MX MZ NO NZ PL PT RO RU SD SE SG SI SK SL TJ TM TR TT TZ UA UG US UZ VN YU ZA ZW

AL Designated countries for regional patents

Kind code of ref document: A1

Designated state(s): GH GM KE LS MW MZ SD SL SZ TZ UG ZM ZW AM AZ BY KG KZ MD RU TJ TM AT BE CH CY DE DK ES FI FR GB GR IE IT LU MC NL PT SE TR BF BJ CF CG CI CM GA GN GQ GW ML MR NE SN TD TG

121 Ep: the epo has been informed by wipo that ep was designated in this application
DFPE Request for preliminary examination filed prior to expiration of 19th month from priority date (pct application filed before 20040101)
REG Reference to national code

Ref country code: DE

Ref legal event code: 8642

122 Ep: pct application non-entry in european phase
NENP Non-entry into the national phase

Ref country code: JP

WWW Wipo information: withdrawn in national office

Country of ref document: JP