WO2019051528A1

WO2019051528A1 - Powered vine shear improvements

Info

Publication number: WO2019051528A1
Application number: PCT/AU2018/000088
Authority: WO
Inventors: Angus MURRAY
Original assignee: MaxiCut Pty Ltd
Priority date: 2017-09-14
Filing date: 2018-06-01
Publication date: 2019-03-21
Also published as: AU2018333267A1

Abstract

The present disclosure relates to shears for woody plants such as vines. In a particular form the present disclosure relates to a power shear system, and a handpiece for such a system. In one aspect, the power shear system comprises a base comprising a power plant, at least one gantry arm assembly depending from the base, a tether dropping from the gantry arm assembly to a handpiece, where the or each handpiece comprises a pair of bypass blades and an hydraulic actuator for the blades, where the actuator is connected to the power plant via at least one hydraulic hose which drops from the gantry arm assembly at a position which is outboard of the tether along the gantry arm assembly.

Description

POWERED VINE SH EAR IMPROVEMENTS

PRIORITY DOCUMENTS

[0001] The present application claims priority from Australian Provisional Patent Application No. 2017903737 titled "POWERED VINE SHEAR IMPROVEMENTS" and filed on 14 September 2017, the content of which is hereby incorporated by reference in its entirety.

TECHNICAL FIELD

[0002] The present disclosure relates to shears for woody plants such as vines. In a particular form the present disclosure relates to a power shear system, and a handpiece for such a system.

BACKGROUND

[0003] Eutypa dieback is a disease caused by a fungus (Eutypa lata) which grows slowly through the wood of infected grapevines and other woody host plants. Vines become infected through fresh wounds such as those made during pruning. Toxins produced by the actively growing fungus cause stunting of the shoot. The fungus eventually kills infected parts of vines and can potentially kill the whole vine.

[0004] There is no cure for this disease, and so it must be removed by pruning diseased vine until no discolouration is seen in the cross section, and then a further 5 cm below that. It will be appreciated that this may involve making numerous cuts through thick vines in short succession. This makes manual shears unviable, but preceding powered shears and their associated powerplants are heavy and unwieldy, and prone to issues with the blades, such as jamming and blade failures.

[0005] It is against this background and the problems and difficulties associated therewith that the present invention has been developed.

[0006] Certain objects and advantages of the present invention will become apparent from the following description, taken in connection with the accompanying drawings, wherein, by way of illustration and example, an embodiment of the present invention is disclosed.

SUMMARY

[0007] According to a first aspect, there is provided a power shear system comprising a base comprising a power plant, at least one gantry arm assembly depending from the base, a tether dropping from the gantry arm to a handpiece, where the or each handpiece comprises a pair of bypass blades and an hydraulic actuator for the blades, where the actuator is driven via at least one hydraulic hose which drops from the gantry arm assembly at a position which is outboard of the tether along the gantry arm assembly.

[0008] In one form, the gantry arm assembly further comprises an underslung spring balancer unit and an underslung pulley, so that the tether can be connected to the spring balancer unit, and passed through the pulley and extended to the handpiece, so that the weight of the handpiece is compensated by the spring balancer unit via the tether.

[0009] In one form, the or each gantry arm assembly comprises a hose guide at or near a distal end thereof, from which the or each hydraulic hose drops to the handpiece.

[0010] In one form, the or each gantry arm assembly comprises a telescopic boom assembly.

[001 1] In one from, the telescopic boom assembly comprises an outer boom member and inner boom member which is telescopically extendable and retractable with respect to the outer boom member so that the boom assembly can be lengthened and shortened as required.

[0012] In one form, the outer boom member comprises the underslung spring balancer unit.

[0013] In one form, the inner boom member comprises the underslung pulley.

[0014] In one form, the inner boom member comprises the hose guide at or near a distal end thereof.

[001 5] In one form, the base comprises connection points for connecting the power shear system to a three point linkage of a tractor.

[0016] In one form, the power shear system comprises two gantry arm assemblies.

[0017] In one form, the two gantry arm assemblies extend in opposing directions.

[0018] In one form, a first gantry arm extends on a first side of the base, and a second gantry arm extends on a second side of the base.

[0019] In one form, the or each actuator comprises a hydraulic cylinder or ram. [0020] In one form, in an alternative, the actuators are pneumatic.

[0021] In one form, the power shear system comprises a control system which controls its operation. [0022] Accordingly, the control system may include a variety of components. Exemplary components may include those that monitor electric signals, switch electric signals, perform sensing functions, and govern activation and deactivation of components such as the drive means.

[0023] Further, the control system may comprise a processor, a memory, storage, and a user interface. The control system may be controlled by software. The control system may provide users with precise control, diagnostic information and performance information for governing the power shear system.

[0024] According to a further aspect, there is provided a handpiece for a power shear system, the hand piece comprising a body, a pair of bypass blades, an hydraulic actuator for the blades and a handle comprising an operator presence control means, wherein in use, if the handle is released by an operator for a predetermined elapsed period, the operator presence control means will open the blades.

[0025] The operator presence control means will not instantaneously open the blades if the handle is released by the operator, as the operator will want to adjust the position of their hands on the handle from time without wanting to cease operation.

[0026] In one form, the handle comprises a generally annular handle body extending around the body of the handpiece.

[0027] In one form, the operator presence control means comprises a switch.

[0028] In one form, the switch extends around an inner edge of the handle body.

[0029] According to a further aspect, there is provided a blade for a handpiece of a power shear system, the blade comprising a generally planar body comprising a bypass face, and an opposing guide face, the body further comprising a blade portion, a tang portion, and a pivot mount portion positioned between the blade and tang portions, the pivot mount portion comprising a hole for the pivot pin on which the blade pivots, and wherein at least one of the bypass face or the guide face of the pivot mount portion comprises at least one groove extending from at or near an edge of the pivot mount portion to the hole for directing grease to the pivot pin.

[0030] In one form, it is the bypass face of the pivot mount portion that comprises the or each groove.

[0031] In one form, in an alternative, it is the guide face of the pivot mount portion that comprises the or each groove. [0032] In one form, in an alternative, both the bypass face and the guide face comprise at least one groove extending from at or near an edge of the pivot mount portion to the hole for directing grease to the pivot pin.

[0033] In one form, the or each of the grooves is shaped to direct grease to the pivot pin as the blades close.

[0034] In one form, the bypass face of the pivot mount portion comprises a plurality of grooves.

[0035] In one form, the plurality of grooves are equispaced.

[0036] In one form, the or each of the grooves is curved.

[0037] In one form, the or each of the grooves is shaped like an arc of a circle.

[0038] In one form, the tang comprises a hole via which the drive link is pivotally connected.

[0039] In one form, the blade portion comprises a leading edge extending from a point of the blade portion to the mounting portion, and a trailing edge extending from the point to the tang,

[0040] In one form, the leading edge comprises a cutting edge which comprises a curved and concave portion, and a short straight edge portion extending from the curved portion to the point of the blade.

[0041] In one form, the trailing edge is curved and convex.

[0042] In one form, the blade portion is tapered to the cutting edge, with a taper on the guide face being substantially longer than a taper on the bypass face.

BRIEF DESCRIPTION OF DRAWINGS

[0043] Embodiments of the present invention will be discussed with reference to the accompanying drawings wherein:

[0044] Figure 1 is a front schematic view of a power shear system with a gantry arm extended and supporting a handpiece;

[0045] Figure 2 is a front schematic view of the power shear system of Figure 1 ;

[0046] Figure 3 is a front view of the power shear system of Figure 1 ; [0047] Figure 4 is a schematic view of the handpiece from the power shear system of Figure 1 ; [0048] Figure 5 is an exploded view of the handpiece of Figure 4; [0049] Figure 6 is a plan view of one of the blades; from the handpiece of Figure 4; and [0050] Figure 7 is an end view of the blade of Figure 6.

[0051 ] In the following description, like reference characters designate like or corresponding parts throughout the figures.

DESCRIPTION OF EMBODIMENTS

[0052] Referring now to Figure 1, where there is illustrated a power shear system 1, the power shear system 1 comprising a base 2 comprising a power plant, two gantry arm assemblies 20 depending from the base 2, and to opposing sides thereof, and a handpiece 100 detachably suspended from one gantry arm assembly 20 (typically a handpiece 100 would be detachably suspended from each gantry arm assembly 20).

[0053] Each of the gantry arm assemblies 20 can be moved between a stowed, retracted position, and an extended in use position. The stowed position is useful for transportation and storage of the power shear system 1. In Figure 1 and 3, one gantry arm assembly 20 is illustrated in its stowed position, and the other is illustrated in its in use position, with a handpiece 100 suspended therefrom.

[0054] Each handpiece 100 comprises a body 102 pivotally supporting a pair of bypass blades 120 and an actuator 1 10 for the blades 120, where the actuator 110 is driven via the power plant.

[0055] In the case of the illustrated embodiment, the actuator 1 10 for the bypass blades 120 comprises a hydraulic ram, and the power plant comprises a tank 10 for hydraulic fluid and a hydraulic pump 12. In this embodiment, the hydraulic pump 12 is driven by a power take off shaft from a tractor (not illustrated), however it will be understood that the power plant could further comprise a motor for driving the pump, so that the power shear system is not limited to use with a vehicle comprising a power take off shaft.

[0056] Hydraulic pressure and flow are equally split to the handpieces 100 when both are in use, to ensure that they are always cutting at the highest efficiency, even when running simultaneously.

[0057] Because the power shear system 1 according to the illustrated embodiment is adapted to be used with a tractor, the base 2 comprises a frame 4 comprising connection points 6 for connecting the power shear system 1 to a three point linkage of a tractor. In use, this means that the power shear system 1 can be tilted forward and rearward (relative to the tractor), which is of use to keep the system vertical when travelling up or down a hill.

[0058] Each gantry arm assembly 20 comprises an upright 22 and a boom assembly 30 depending from the top of the upright 22. Each upright 22 is pivotally secured to the frame 4 of the base 2 on a turntable bearing 23 so that the gantry arm assembly 20 can be slewed as required.

[0059] Each boom assembly 30 comprises an outer boom member 32 and inner boom member 34 which is telescopically extendable and retractable with respect to the outer boom member 32 so that the boom assembly 30 can be lengthened and shortened as required. This is of use where spacing between rows of vines varies.

[0060] Each outer boom member 32 comprises a crank 36 which is pivotally secured to the upright 22 so that the boom assembly 32 can be tilted up and down as required. This crank 36 further comprises an attachment point 38 for an arm actuator 50, which extends between this crank 36 attachment point, and an upright attachment point 39.

[0061] In the case of the illustrated embodiment, the arm actuator 50 comprises a hydraulic ram. The arm actuator 50 raises and lowers the boom assembly 30, and maintains the boom assembly 30 in an in use position.

[0062] There is a spring balancer 60 unit depending from an underside of each outer boom member 32, and each inner boom member 34 carries a suspended pulley 62, so that a tether 64 (a cable in this case) can be connected to the spring balancer unit 60, and passed through the pulley 62 and extended to the handpiece 100, so that the weight of the handpiece 100 is compensated by the spring balancer unit 60 via the cable 64 and boom assembly 30. This significantly reduces the physical effort required by an operator to handle a handpiece 100. The crank 36 comprises a relief to accommodate the spring balancer 60.

[0063] The outer boom 34 carries hydraulic hoses 37 which terminate at connectors for hoses extending to the handpiece 100. In this way the handpieces 100 and their hoses are detachable for storage. The inner boom 36 comprises a guide 35 for the hoses to the handpiece 100 at its distal end.

[0064] This arrangement means that the hydraulic hoses drop from the boom assembly 30 of the gantry arm assembly 20 at a position which is outboard of the tether 64 (cable) along the boom assembly 30. In use then, the hydraulic hoses are behind the operator, and well away from the blades 120 of the handpiece 100. The result of this is that the hoses cannot be accidently cut by the blades 120, and they will not get in the way of the operator as they are cutting. Moreover, the operator is further away from the hoses in case of hydraulic leaks.

[0065] We refer now to Figures 4 through 7, and to the handpiece 100.

[0066] The hydraulic ram 1 10 for the handpiece 100 comprises a rod 104 which extends through a cylindrical body 102 (comprised of parts 102A and 102B) for the handpiece 100 to a yoke 108 which is pivotally attached to the end of the rod 104. The yoke 108 comprises a pair of oppositely and outwardly directed tabs.

[0067] A hanging ring 1 12 is disposed over the body 102 so that the hanging ring 1 12 can swivel around the body 102. This means the body 102 of the handpiece 100 can pivot about its longitudinal axis in the hanging ring 1 12. The cable 64 is detachably attached to the hanging ring 112 and thus the handpiece 100 via a D-shackle 1 13. The hanging ring 1 12 is positioned at the balance point of the handpiece 100, so that the handpiece is balanced about the hanging ring 112 and therefore tending to extend horizontally to either side of the hanging ring 1 12.

[0068] The body 102 comprises a pair of parallel, spaced apart arms 1 14, and a pivot pin 1 15 extending between the arms 114, to which pivot pin 1 15 there is pivotally mounted the pair of bypass blades 120. Each of the arms 114 comprises a guide slot extending therealong, to guide movement of the yoke 108.

[0069] Each of the blades 120 comprises a generally planar body 122 comprising a bypass face 122A, and an opposing guide face 122B, the body 122 further comprising a blade portion 130, a tang portion 124, and a pivot mount portion 126 positioned between the blade 130 and tang 124 portions, the pivot mount portion 126 comprising a hole 128 for the pivot pin on which the blade pivots. A drive link extends between, and is pivotally attached to each of, one of the tabs of the yoke and the tang of one of the blades.

[0070] In use, as the hydraulic cylinder 110 extends, the yoke 108 and drive links 1 16 transfer drive to close the blades 120, and then open the blades 120 as the cylinder 1 10 retracts.

[0071] The handpiece 100 comprises a forward handle assembly 140, which comprises a handle mounting bracket 142 secured to the body 102 of the handpiece 100, a forward handle 144 which depends from the bracket 142, and a hand guard 146 which depends from the bracket 142 at a position forward of the forward handle 144. The forward handle 144 is shaped like a ring extending around the body 102 of the handpiece 100, with a pair of ends of the forward handle 144 terminating at the bracket 142. Similar to the forward handle 144, the hand guard 146 is shaped like a ring extending around the body 102 of the handpiece 100, with a pair of ends of the hand guard 146 terminating at the bracket 142. [0072] To a back end of the hydraulic cylinder 100 there is attached a rear handle 150 which extends lengthwise.

[0073] The power shear system comprises an operator presence control means, wherein in use, if the forward handle 144 is released by an operator for a predetermined elapsed period, the operator presence control means will open the blades 120 and isolate the or each handpiece to prevent further operation until an all clear is given. In use then, when the operator is not in full control of the handpiece, the operator presence control means should prevent unintended operation of handpiece 100, where such unintended operation could result in an unintended cutting operation that may cause damage or injury.

[0074] To this end, the forward handle 144 of the handpiece 100 comprises a switch 148 which extends approximately 270° (in this case) around an inner edge thereof. In this way, the operator can rotate the handpiece up to 270°to position the handpiece to make cuts as required, and still have the ability to activate the switch 148 by releasing the same.

[0075] The switches 148 comprises a delay or timer function to stop the jaws from opening when the operator momentarily takes their hand off of the switch 148, such as may result from a slight jerk from cutting, or the operator adjusting their grip. A 0.5 second delay would allow enough time for the operator to regain grip, but not allow them enough time to get their hands between the blades.

[0076] This power shear system 1 comprises a control system which, amongst its numerous functions, is control of this operator presence control means.

[0077] If this control system detects any irregularity in operation of the power shear system 1, such as an electrical, electronic or hydraulic failure or overload, then the blades 120 will be opened and the or each handpiece 100 isolated.

[0078] Referring now to Figures 6 and 7, where it can be seen that the blade portion 130 comprises a leading edge LE extending from a point P of the blade portion 130 to the mounting portion 126, and a trailing edge TE extending from the point P to the tang 124.

[0079] The leading edge LE comprises a cutting edge which comprises a curved and concave portion, and a short straight edge portion SE extending from the curved portion to the point P of the blade 130. The trailing edge TE is curved and convex. The curved and concave portion of the cutting edge prevents the blades from crossing over and becoming jammed and/or damaged. [0080] A thickness of the blades 120 tapers down to an edge at the point P on the tip of the blade, which prevents the blades 120 from crossing over when the flexure is enough to force the tips to close together. If the blades 120 are able to cross over, this can break them.

[0081 ] The cutting edge comprises a blunt face so that the blades 130 can cut wire without suffering damage. In the case of the illustrated embodiment, the blunt face is about 3mm thick.

[0082] Both the bypass face 122A and opposing guide face 122B of the body 122 of the blade portion 130 is tapered to the cutting edge, with a taper Tlon the guide face 122B being substantially longer than a taper T2 on the shear face 122A. These tapers Tl and T2 help to prevent splitting of the wood.

[0083] The pivot mount portion 126 comprises a generally circular planform extending concentrically around the hole 128 for the pivot pin. The diameter of this circular planform substantially matches a depth of the arms 1 14 of the body 102, so as to provide a guide surface area to prevent any misalignment of the blades 130 in use, where misalignment can result in jamming, damage and downtime.

[0084] The bypass face 122B of the pivot mount portion 126 comprises a plurality of equispaced grooves 160 extending from near an edge of the pivot mount portion 126 to the hole 128. Each of the grooves 160 is shaped like an arc of a circle to direct grease applied at the edge to the pivot pin 115 as the blades 130 close.

[0085] In use then, grease is supplied to the pivot pin 115 and the adjacent shear faces 122A of the bypass blades to ensure smooth, trouble free operation and reduced downtime due to failures. The grooves 160 can also aid in expelling any contamination which finds its way between the blades 130.

[0086] The power shear system disclosed herein incorporates features which improve efficiency, safety, durability and reliability.

[0087] Throughout the specification and the claims that follow, unless the context requires otherwise, the words "comprise" and "include" and variations such as "comprising" and "including" will be understood to imply the inclusion of a stated integer or group of integers, but not the exclusion of any other integer or group of integers.

[0088] The reference to any prior art in this specification is not, and should not be taken as, an acknowledgement of any form of suggestion that such prior art forms part of the common general knowledge. [0089] It will be appreciated by those skilled in the art that the invention is not restricted in its use to the particular application described. Neither is the present invention restricted in its preferred embodiment with regard to the particular elements and/or features described or depicted herein. It will be appreciated that the invention is not limited to the embodiment or embodiments disclosed, but is capable of numerous rearrangements, modifications and substitutions without departing from the scope of the invention as set forth and defined by the following claims.

Claims

1. A power shear system comprising a base comprising a power plant, at least one gantry arm assembly depending from the base, a tether dropping from the gantry arm assembly to a handpiece, where the or each handpiece comprises a pair of bypass blades and an hydraulic actuator for the blades, where the actuator is connected to the power plant via at least one hydraulic hose which drops from the gantry arm assembly at a position which is outboard of the tether along the gantry arm assembly.

2. The power shear system of claim 1, wherein the gantry arm assembly further comprises an underslung spring balancer unit and an underslung pulley, so that the tether can be connected to the spring balancer unit, and passed through the pulley and extended to the handpiece, so that the weight of the handpiece is compensated by the spring balancer unit via the tether.

3. The power shear system as in either of the preceding claims, wherein the or each gantry arm assembly comprises a hose guide at or near a distal end thereof, from which the or each hydraulic hose drops to the handpiece.

4. The power shear system as in any one of the preceding claims, wherein the or each gantry arm assembly comprises a telescopic boom assembly comprising an outer boom member and inner boom member which is telescopically extendable and retractable with respect to the outer boom member so that the boom assembly can be lengthened and shortened as required.

5. The power shear system of claim 4, wherein the outer boom member comprises the underslung spring balancer unit.

6. The power shear system as in either of claims 4 or 5, wherein the inner boom member comprises the underslung pulley.

7. The power shear system as in any one of claims 3 through 6, wherein the inner boom member comprises the hose guide at or near a distal end thereof.

8. The power shear system as in any one of the preceding claims, wherein the base comprises connection points for connecting the power shear system to a three point linkage of a tractor.

9. The power shear system as in any one of the preceding claims, wherein the power shear system comprises two gantry arm assemblies.

10. The power shear system as in any one of the preceding claims, wherein the handpiece comprises a body, the pair of bypass blades, the hydraulic actuator for the blades, and a handle comprising an operator presence control means, wherein in use, if the handle is released by an operator for a predetermined elapsed period, the operator presence control means will open the blades.

11. The power shear system of claim 10, wherein the handle comprises a generally annular handle body extending around the body of the handpiece.

12. The power shear system as in either of claims 10 or 1 1 , wherein the operator presence control means comprises a switch.

13. The power shear system of claim 12, wherein the switch extends around an inner edge of the handle body.

14. The power shear system as in any one of the preceding claims, wherein each comprises a generally planar body, the body comprising a bypass face, and an opposing guide face, the body further comprising a blade portion, a tang portion, and a pivot mount portion positioned between the blade and tang portions, the pivot mount portion comprising a hole for the pivot pin on which the blade pivots, and wherein at least one of the bypass face or the guide face of the pivot mount portion comprises at least one groove extending from at or near an edge of the pivot mount portion to the hole for directing grease to the pivot pin.

15. The power shear system of claim 14, wherein it is the bypass face of the pivot mount portion that comprises the or each groove.

16. The power shear system of claim 14, wherein it is the guide face of the pivot mount portion that comprises the or each groove.

17. The power shear system of claim 14, wherein both the bypass face and the guide face comprise at least one groove extending from at or near an edge of the pivot mount portion to the hole for directing grease to the pivot pin.

18. The power shear system as in any one of claims 14 through 17, wherein the or each of the grooves is shaped to direct grease to the pivot pin as the blades close.

19. The power shear system as in any one of claims 14 through 18, wherein the pivot mount portion comprises a plurality of grooves.

The power shear system of claim 19, wherein the plurality of grooves are equispaced.

21. The power shear system as in any one of claims 14 through 20, wherein the or each of the grooves is curved.

22. The power shear system as in any one of claims 14 through 21, wherein the or each of the grooves is shaped like an arc of a circle.

23. The power shear system as in any one of claims 14 through 22, wherein the tang comprises a hole via which the drive link is pivotally connected.

24. The power shear system as in any one of claims 14 through 23, wherein the blade portion comprises a leading edge extending from a point of the blade portion to the mounting portion, and a trailing edge extending from the point to the tang,

25. The power shear system of claim 24, wherein the leading edge comprises a cutting edge which comprises a curved and concave portion, and a short straight edge portion extending from the curved portion to the point of the blade.

26. The power shear system as in either of claims 24 or 25, wherein the trailing edge is curved and convex.

27. The power shear system as in either of claims 25 or 26, wherein the blade portion is tapered to the cutting edge, with a taper on the guide face being substantially longer than a taper on the bypass face.