FI97939C - Shaving head for shears - Google Patents

Description

1 97939

Shrub head. - Skärhuvud för busksax.

This invention relates to shrub cutting machines, and more particularly to the working end of a hedge trimmer or clearing plow having a protective hood provided with a blade opening, a retractable spray nozzle aligned with the opening, and a gripping thumb having a flat non-operative position.

Shrub cutting procedures have many purposes. Some of the 10 main purposes are to clear public access rights and road sides of obstructive vegetation and to thin trees for land management. In such situations, it is, of course, desirable to slow the regrowth of the cut vegetation and maximize the period of time before the need to repeat the cleaning or thinning operations. One method of slowing regrowth is to spray the cut areas with suitable chemicals. Because pruned vegetation, such as tree stumps, tends to close almost immediately, it is important that any spraying operation be carried out as soon as possible after pruning. For this reason, it is not uncommon for a surgical contractor to be required to spray within ten minutes of surgery.

The need for rapid spraying of cut areas is difficult to satisfy due to the lack of shrub cutting equipment that is suitable for both clearing passages and / or thinning trees and capable of spraying operations. Today, the most common method of performing spraying is to use a walking worker equipped with a portable chemical container on his back and a hand-held sprayer that follows the brushcutter. This procedure is tedious and laborious, and thus quite expensive. In addition, the procedure exposes the employee to unfavorable working conditions. Because the worker must maintain a safe distance from the shrub cutting machine, this procedure also includes 2,97939 of the unavoidable delay in spraying following shrub cutting. In addition, due to the relative distance of the cutting operation and the unavoidable covering of the cut area with cut shrubs 5 and debris, it is very difficult for the worker to accurately identify the areas that require spraying. Even when areas are identified, the nature of hand spraying generally results in uneven coverage. The result is a tendency to over-spray and / or uneven spraying when some of the areas 10 receive insufficient spraying.

Another problem associated with known shrub cutting equipment is that elements mounted on the workhead can prevent cutting operations and are prone to fouling caused by contact with mud and debris and damage caused by their adherence to vegetation and other objects. This makes it difficult to install the gripper and its actuators at or near the workhead without increasing repair and maintenance costs.

Spray accessories for lawn mowers are disclosed in U.S. Patent Nos. 2,737,340, issued March 6, 1956 to R.A. Bonini; No. 2,908,444, issued October 13, 1959, to A.R. Mullin; 25 No. 3,017,121, issued January 16, 1962, to V.W. Carlson; No. 3,100,371, issued August 13, 1963, to P.C. Redmon; and No. 3,857,515, issued December 31, 1974 to M.M. Zennie. The Bonin attachment is mounted on the mower base in conjunction with the engine and can be used simultaneously with or independently of the mowing and traction mechanisms to inject fluid. The location of the injector, which is connected to the chassis-mounted compressor by a hose, is unclear. Mullin presents a spray attachment for a lawn mower with a rotating cutting bar similar to a fan blade. The spray attachment is mounted on the drive shaft above the cutting bar. Centrifugal force transports fluid through the circumferential slits; and the liquid is deflected 3 97939 downwards so that it is applied only below the cutter. Carlson and Zennie each describe a power-driven lawnmower accessory with a perforated exhaust manifold mounted in a fixed position offset from the 5 mowers. The Carlson attachment is powered by the cutter exhaust. The Zennie accessory is powered by a fan that is powered by the mower motor. Redmon describes a lawn mower accessory with a funnel mounted in a mower housing that dispenses fluid onto the blade or blade path 10 only when the mower is in motion.

U.S. Patent No. 3,982,697, issued September 28, 1976 to H. E. Maples, discloses a spray attachment for a mower of the type used on a golf course green. The liquid is received from a distant source through an inlet mounted above the mower and distributed behind the mower. The accessories have valves to control the distribution of the liquid. U.S. Patent No. 4,551,968, issued November 12, 1985 to B. A. Samuelsson, discloses an spray device 20 mounted on a self-propelled combine. The spray device includes a tubular liquid spreader equipped with a plurality of nozzles. The spreader is located behind the front cutting deck. The spreader sprays the herbicide after harvesting but before the 25 crop residues settle.

U.S. Patent No. 2,331,373, issued October 12, 1943, to F. A. Campbell, discloses a liquid outflow application for firefighting, gardening or painting buildings. 30 The application resembles a rigid hose and has tubes that are telescopically extended relative to each other by a medium flowing into the application. Cutter accessories with a housing provided with a blade revealing opening are described in U.S. Patent Nos. 3,241,302, issued March 22, 1966 to R. 0. Barry; No. 4,509,315, issued April 9, 1985, to N. Giguere; and No. 4,802,327, issued February 7, 1989 to C. A. Roberts.

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The mechanisms of adhesion are disclosed in U.S. Patent Nos. 4,269,241, issued May 26, 1981 to L. Hickman; No. 4,376,340, issued March 15, 1983 to M. Ramun et al .; No. 4,446,897, issued May 8, 1984 to J. Kurelek; and No. 4,491,163, issued January 1, 1985, 5 J. Kurelek. The Ramun et al. Device is an accessory for a backhoe loader, in which the gripping jaws have inner edges with a Saxon-type function. The other three patents disclose wood felling devices in which wood is gripped during cutting.

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The present invention is directed to shrub or vesicle cutting devices. A work end according to an aspect of the invention is characterized by the features set forth in the characterizing part of claim 1. The working head for a shrub-15 cutting machine according to the invention comprises a housing and a cutting blade supported by the housing. The housing includes a protective hood with a vertical opening to expose a portion of the blade to allow the blade to cut the bush. The spray nozzle is also supported by a housing. The nozzle has a rye-20 call position where it is substantially aligned with the opening above and outside the exposed portion of the blade. The activator is remote from the housing and operatively connected to the nozzle to selectively inject liquid therefrom. Preferably, the nozzle is slidably retractable to a non-operative position. Likewise, preferably the opening extends through the side part of the hood, and, in its spraying position, the nozzle is arranged laterally outwards from the exposed part of the blade.

The features of the invention described above can be incorporated into different types of workheads. For example, the blade may be a generally circular rotating cutting blade mounted for rotation about a vertical axis and extending radially outwardly through a vertical opening in the dome. The work end may also be provided with a further advantageous feature according to the invention. For example, the nozzle may be adjustable and / or a plurality of nozzles may be arranged to allow adjustability and flexibility of the liquid spray pattern. The arrangement of several nozzles also allows the selective spraying of one or more different liquids.

The invention includes the working head described above per se, as well as a working end together with a boom, in which the boom has an end part to which the working end is pivotally attached.

A bush trimmer according to another aspect of the invention is characterized by the features set forth in the characterizing portion of claim 9. The shrub cutting device according to the invention comprises a boom with opposite end portions and a combination of a working end pivotally connected to one end portion. The workhead includes a housing and a cutting blade supported by the housing 15. The housing includes a blade portion around the protective hood. The spray nozzle is mounted in the housing and can be flagged between the off position and the spray position. In the non-operating position, the nozzle is located above the housing part. In the spray position, the nozzle 20 protrudes horizontally outward from the housing to allow liquid to be sprayed downward from the nozzle onto the shrub cut. An actuator remote from the housing is operatively connected to the nozzle to selectively inject liquid therefrom. The possibility of the nozzle sliding between the two positions 25 has the advantage of allowing the nozzle to be placed during the cutting operations in a position which is not in use, where it does not obstruct the cutting operations and is not prone to fouling or damage.

A work end according to another aspect of the invention is characterized by the features set forth in the characterizing part of claim 11. The working head for the brushcutter comprises a housing, a cutting blade supported by the housing, and a gripping jaw supported by the lower part of the housing. The thumb is pivotally mounted in the housing for pivoting about a horizontal axis. The thumb turns from the non-used position towards the chin to grasp the bush cut with this and 6,97939 other debris between the thumb and the housing. In the non-operating position, the thumb is at least substantially flush with the top of the housing. The actuator is mounted inside the housing and connected to the thumb for turning the thumb around its axis. This combination of features at the workhead provides the head with the ability to grip waste while avoiding the contamination and prevention problems described above. The flat position of the thumb in its inoperative position and the mounting of the actuator on the inside of the housing) protect the thumb and the actuator and prevent these elements from interfering with the surgical procedure.

The spraying aspect of the invention provides flexible, cost-effective means for performing the required spraying and shrub-cutting operations. Placing the spray nozzle on the cutting head allows spraying to be performed immediately as soon as the area is cut. Immediate spraying prevents any overgrowth of cut stems and other vegetation before spraying. Therefore, spraying efficiency is maximized.

The positioning of the spray nozzle at the workhead and the provision of a remote activator also allow spraying to be carried out quickly and easily by the user of the brushcutter. This eliminates the need for an additional 25 workers on foot and significantly reduces labor costs. In addition, the machine operator can be isolated from the chemical to be sprayed without interfering with the spraying operation. Since the cutting operation has just been performed by the machine operator, the operator has accurate first-hand knowledge of the points that require spraying. This allows the user to spray only where necessary. It also prevents the problem of uneven spraying and missing spots encountered in a conventional manual spraying procedure. The feature of the spray nozzle of the invention in that it extends laterally at the working end provides the user with maximum visibility to help maximize spraying accuracy. The retractability of the nozzle helps to protect the nozzle 7 97939 and to avoid the contamination and prevention problems described above.

Positioning the nozzle, in its spray position, aligned with the blade opening in the hood 5 allows for maximum compactness of the workhead in the spray structure, while preventing chemicals from being sprayed directly onto the housing or blade.

These and other advantages and features will become apparent from the following detailed description of the best mode for carrying out the invention.

In the drawings, the corresponding markings on the elements refer to the corresponding parts throughout, and:

Figure 1 is a vertical view of a shrub cutting machine incorporating a preferred embodiment of the invention.

Fig. 2 is a descriptive view of a preferred embodiment of a workhead showing the spray nozzles and the thumb in their inoperative position.

Figure 3 is similar to Figure 2 except that it shows the thumb used to grip the cut shrub.

Figure 4 is a bottom plan view of the workhead shown in Figures 1-3 with the nozzles in their spray position.

30

Fig. 5 is a plan view of the working end shown in Figs. 1 to 4 with the upper cover removed.

Fig. 6 is similar to Fig. 2 except that it 35 shows the nozzles in their extended spray position for spraying liquid.

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Figure 7 is a descriptive view of the injection system components of a preferred embodiment.

Fig. 8 is an exploded view of parts of the device shown in Fig. 7.

Figure 9 is an exploded exploded view of the container shown in Figure 7 and its support base.

Fig. 10 is an exploded view of the nozzles shown in Figs. 6-8 and their slide base.

The drawings show a shrub cutting device constructed in accordance with the invention, which constitutes the best mode currently known to the applicant for carrying out the invention. As shown in Fig. 1, the device is connected to a tractor 2 of a conventional type in a two-boom arrangement. The tractor 2 and the associated structure are shown here for the purpose of illustrating an installation of the device 20 according to the invention. It is, of course, to be understood that the invention may be utilized in connection with other types of tractors, tractor excavators and similar machines, and in connection with other boom arrangements. Another example of another suitable boom arrangement is the three triple boom arrangement described in Applicant's U.S. Patent No. 4,769,977, issued September 13, 1988.

Referring to Figure 1, the tractor 2 has a cab 4 for the driver and a turntable 5 mounted to pivot about a vertical axis 30. The vertical column 6 is mounted on the turntable 5. The boom 8, which is of a known type, is pivotally mounted on the column 6 to pivot about a horizontal axis. The hydraulic actuator 10 pivots the boom 8. The outer boom or rod 12 is pivotally mounted on the outer end 35 of the inner boom 8. The rod 12 is pivoted relative to the boom 8 by means of a hydraulic actuator 14. The actuator 14 is supported by a boom 8.

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Referring to Figures 1 to 6, the preferred embodiment of the working head 20 according to the invention is pivotally mounted on the outer end of the rod 12. As noted above, the invention includes both the workhead 20 itself and a combination of the workhead 20 and rod 12. The work end 20 is pivotable about a horizontal axis relative to the rod 12. The rotation of the working head 20 is effected by a hydraulic actuator 22 pivotally connected to the rod 12 and engaging the upper rear fork portion 32 of the working head 20. The rod 12 is pivotally connected to the fork 32 and coupled to the piston portion of the actuator 22 the boom structure in a known manner to the control system of the tractor 2. The bundle 26 includes hydraulic hoses and wiring to operate the cutting blade 42 15 and injection mechanism described more further below.

The work end 20 includes a housing 28. The upper portion 30 of the housing 28 is vertical and terminates at its upper end in a rearwardly projecting fork 32 mentioned above. On the front side-20a of the fork 32, on the upper vertical part 30, there is a removable cover 34. The cover 34 at least substantially closes the upper part 30 of the housing 28 to exclude mud and debris and thereby protect the components mounted inside. The lower part of the housing 28 forms a protective dome 36. A jaw 38 comprising a plurality of teeth is formed on the lower rear edge of the dome 36. A substantially circular horizontally rotating cutting blade 42 is mounted in the housing 28 to rotate about a vertical axis. The circumferential edge of the blade 42 is substantially surrounded by a dome 36. The mounting structure for the blade 42 may comprise a number of different shapes and preferably includes the sludge pocket arrangement described in Applicant's aforementioned U.S. Patent No. 4,769,977. The arrangement of the cutting edges of the blade 42 can also vary considerably. The currently preferred structure is best seen in Figure 35 4. It has four circumferential cutting teeth 41 and four teeth 43 on its base surface.

97939 10

Figure 36 has a vertical side opening 40 extending therethrough to expose a portion of the blade 42 to allow the blade 42 to engage and cut the bush. Shrub cutting heads are conventionally provided with openings in the protective hood for this purpose. However, the openings are generally in front of the workhead, rather than in the side portion of the workhead, as in the preferred embodiment shown in the drawings of the workhead 20 and described herein.

The gripping thumb 44 is also pivotally mounted on the working head 20. The advantage of providing a thumb 44 mounted directly on the working head 20 is that when the working head 20 is mounted on an existing articulated boom structure, the structure is automatically provided with gripping capacity as well as shear capacity. The thumb 44 is pivotable about a horizontal axis between a non-operative position in which it is substantially flat against the lower surface of the fork 32 and a gripping position in which it cooperates with the jaw 38 to grip the Lei-20 covered shrub and other debris from the housing. 28 and between the thumb 44. The flat inoperative position is shown in Figures 1, 2 and 6. The gripping position is shown in Figures 3 to 5. As best seen in Figure 3, the thumb 44 has opposing side flanges 46 and an outer end flange 25 48 extending backward (in the engaging position) or upward (in the inoperative position) from the thumb. In the non-operating position, these flanges 46, 48 extend around the lower edge portion of the fork 32 to enhance conventional gripping of the fork with the thumb 44.

30

The hydraulic actuator 52 for the thumb 44 can be seen in Figure 5. The actuator 52 is mounted inside the upper vertical portion 30 of the housing 28. It can be seen in Figure 5 because the cover 34 has been removed. The actuator 52 35 is used to pivot the hinge / anchor pin 50. The pin 50 is wedged into the thumb 44 so that turning the pin 50

K

1 1 97939 causes the thumb 40 to be turned towards the jaw 38 to grip the bush and other debris, and in the opposite direction to its inoperative position, shown in Figures 1, 2 and 6. The actuator 52 is a conventional double-acting hydraulic cylinder 5 connected to the hydraulic system of the tractor 2. Positioning the actuator 52 and pin 50 within the closed housing portion 30 provides maximum protection for the thumb drive mechanism to assist in minimizing the maintenance and repair costs associated with the thumb. (It should be noted that components that are not relevant to the present invention have been omitted from Figure 5 for clarity.)

A preferred embodiment of the injection mechanism of the invention includes a square tube housing 58. The tube housing 58 is mounted in and integrated into the workhead housing 28. The tubes 58 extend through the front of the vertical top 30 of the workhead housing 28. As can be seen in Figures 2, 3, 5 and 6, the opposite ends of the tubular housing 58 protrude laterally 20 outwardly from the upper housing portion 30.

Referring to Figures 7 and 8, one end of the tubular housing 58 is closed by an end plate 60. An opening 66 is formed in the upper surface of the housing 58. The housing 58 is provided with a wear-resistant support plate 68 attached to the upper surface and covering the opening 66. The plate 68 has three elongate slots 70 extending therethrough to allow hoses 72, 84 to extend upwardly out of the housing 58 through the slits 70, as shown in Figure 7. The slider 74 and the hydraulic actuator 64 for this purpose are received in the housing 58. These elements can be seen in the exploded view shown in Fig. 8. The actuator 64 is held in place by an anchor pin 62 extending through suitable holes in the side of the housing 58. The actuator 64 is operated by a slide-35 slider 74 between a non-operating retracted position, shown in Figures 1-3 and 5, and a protruding operating position, shown in Figures 4, 6 and 7. In the retracted, non-operating position, the end plate 76 supported by the slider 74 closes the end of the tubular housing 58 opposite the fixed end plate 60. In the protruding operating position (spray position), the slider protrudes horizontally 5 laterally outwardly from the housings 28. there are two bearing strips 78 connected to each of the four elongate sides to ensure even sliding of the member 74 in the housing 58. Like the support plates 68, the strips 78 are formed of a resistant chemical resistant material such as nylon.

As can be seen in Fig. 10, the lower surface of the sliding members 74 has an opening 80 formed therein. Two nozzles 82 are mounted on the member 74 and positioned to inject a liquid, such as a herbicide, downwardly through the opening 80. The fluid is fed to the nozzles 82 through a hose 84 extending through the rear of the slider 74 and upwardly out of the tube housing 58 through a single slot 70 in the support plate 68, as can be seen in Figures 7 and 8. The hose 84 is preferably made of a durable, chemical resistant material. An example of a suitable hose is a hose sold under the trademark Dayco with a stainless steel braided jacket with a Teflon (trademark) liner.

25

Figure 7 also shows other components of the injection system. The system includes a hydraulic valve 65, which may be of numerous known types. This valve 65 is connected by two hoses 72 to the actuator 64 to drive the actuator 64 30. Valve 65 can be installed in various locations in the shrub cutting equipment. As shown in Figure 5, a suitable location is inside the upper vertical portion 30 of the workhead housing 28 adjacent the thumb actuator 25. The hoses 72 project from the valve 65 into the tubular housing 58 through two slots 70 in the support plate 68.

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Referring further to Figure 7, a hose 84 that supplies fluid to nozzles 82 is connected at its distal end to a filter 86. The filter 86 is in turn connected to a pump 88 connected to a reservoir 90. In the illustrated embodiment, the pump 88 is electric and is operated. such as the hydraulic components of the device shown in Figure 1, from the cab 2 of the tractor. The filter 86, pump 88, and reservoir 90 may be mounted at any suitable location in the shrub cutting device. It is currently preferred to install these elements 10 on the tractor 2 outside the cab 4, as shown in Figure 1. In this preferred arrangement, the entire activation mechanism for the nozzles 82 is located remote from the working end 20. In other embodiments, activation mechanism components such as filter 86 and / or or the pump 88, 15 may be located at or near the working end 20. However, the trigger mechanism should be located at a distance, preferably in cabin 4, to isolate the user from chemicals and to maximize ease of operation.

Figure 9 is an exploded view of the container device. The container 90 comprises a main body 92, which forms a liquid container. It also comprises a base 94 to which the lower part of the container 92 is slidably received. Removable latches 96 provide a connection between the reservoir 92 and the base 94. The container 92 has a handle 92 at its upper end to allow it to be manually removed from the base 94. As shown in Figures 7 and 9, the latches 96 are tightened with wing nuts. Shakes could also take several other forms. For example, snap fasteners would have the advantage of quick and easy operation. The two-part design of the tank 90 allows the injection mechanism to be easily re-fed with the desired liquid chemical while maintaining a secure installation of the tank on the tractor 2. When empty, the tank 92 with a full tank or refill in a suitable place.

1 4 97939

The drawings show a simple fluid supply system for nozzles, including hose 84, filter 86, pump 88, and reservoir 90. This system may be connected to either or both nozzles 82. The device of the invention 5 may also include an additional fluid supply system including, for example, the same elements 84, 86, 88, 90 than the system shown. In such a case, the two containers 90 may contain two different fluids, such as two different herbicides or herbicides and fertilizer, and each feed system would be connected to a different nozzle 82. The user could then selectively use an appropriate trigger mechanism to spray either. as necessary.

15

In the operation of the described device, the hydraulic and electrical components of the device are controlled by the user in the cab 4 of the tractor 2. This can be done in a known manner. The guides are used to turn the turntable 5, the booms 8, 12 and 20 the working heads 20 to place the working head 20 and the blade 42 for cutting the bush. The blade 42 is preferably driven by a hydraulic motor mounted in the housing 28. Upon completion of cutting in the area requiring spraying, the user stops the rotation of the blade 42 and locates the work head 20 to spray at appropriate points. Valve 65 and actuator 64 are used to extend the slider 74 to its protruding operating position, shown in Figures 4, 6 and 7. Pump 88 is then used to inject liquid from nozzle 82, as shown in Figures 6 and 10. Liquid may be injected from one or both nozzles 82 to increase the injection intensity. to vary and vary the spray pattern. In addition, the nozzles 82 are preferably adjustable in a known manner to provide additional adjustability of the spray pattern. As can be seen in Figures 4 and 6, when the slider 74 is in its position of use, the nozzles 82 are aligned with the opening 40 and above and laterally outwardly from the blade 42. That is, a portion of the blade 42 extends 97939 15 radially outwardly through the opening 40, and the nozzles 82 are radially outside the blade 42. When the slider 72 is retracted to its inoperative position, the member 74 and the nozzles 82 supported by it are located above the portion 5 of the housing 28.

As used herein, the terms horizontal, vertical, upper, lower, and the like refer to the orientation of the working head shown in Figs. 1 to 3 and 6. They are used here to facilitate the description of the structure and operation of the device according to the invention, they are in no way intended to limit the operating orientation of the working head according to the invention to that shown in Figures 1 to 3 and 6.

Although a preferred embodiment of the invention has been shown and described herein, it is intended that those skilled in the art will appreciate that various modifications and omissions in form and detail may be made without departing from the spirit and scope of the invention as defined in the following claims.

Claims (11)

97939 16 A workhead (20) for a brushcutter, the workhead comprising: a housing (28); a cutting blade (42) supported by the housing (28); wherein the housing (28) includes a protective hood (36) having an opening (40) extending therethrough to expose a portion of the blade (42) to allow the blade (42) to cut the bush, characterized by: a spray nozzle (82) supported by the housing (28) , the nozzle having a spray position where the nozzle (82) is substantially aligned with the opening (40) outwardly of said portion of the blade (42) to allow liquid to be sprayed from the nozzle 15 onto a cut bush; and an activator (88) remote from the housing (28) and operatively coupled to the nozzle (82) to selectively inject fluid therefrom. Workhead according to Claim 1, characterized in that the nozzle (82) can be slidably retracted to a position which is not in use. Workhead according to Claim 2, characterized in that the opening (40) in the hood (36) extends through the side part of the hood (36); and the nozzle (82), in said spraying position, is positioned laterally outside said portion of the blade (42). Workhead according to one of Claims 1 to 3, characterized in that the blade (42) is a generally circular rotating cutting blade mounted for rotation about a vertical axis and extending radially outwards through the opening (40). 1 A workhead according to claim 1, characterized in that the nozzle (82) is adjustable to form an adjustable spray pattern of said liquid. 97939 17 Workhead according to claim 1 or 5, characterized in that it comprises a plurality of nozzles (82) having said spraying position. Workhead according to claim 1, 2, 3 or 4, characterized in that it further comprises a gripping jaw (38) supported by the lower part of the housing (28); and a thumb (44) pivotally mounted on the housing (28) to pivot from an inoperative position (Figures 1, 2 and 6), wherein the thumb lo (44) is at least substantially flush with the top of the housing (28), toward the jaw ( 38) and thereby adhere to the cut shrub and other debris between the thumb (44) and the housing (28). A combination of a working head (20) and a boom according to any one of claims 1 to 7, wherein the boom has an end portion to which said working end is pivotally connected. A shrub cutting machine comprising a combination of: 20 a boom (12) having opposite end portions; and a work end (20) pivotally connected to said end portions, said work end (20) comprising: a housing (28): a cutting blade (42) supported by the housing (28); 25 wherein the housing (28) includes a portion of the blade (42) surrounding the protective hood (36), characterized by: a spray nozzle (82) mounted on the housing (28); wherein the nozzle (82) is releasable between an inoperative position and a spray position, wherein in said non-use position, the nozzle (82) is blocked by a portion of the housing (28), and in the spray position the nozzle (82) is directed to the housing (28); past the blade (42) to allow liquid to be sprayed downward from the nozzle onto the shrub cut; and 35 activators (88) remote from the housing (28) and operatively coupled to the nozzle (82) for selectively injecting fluid therefrom. 97939 18 Device according to Claim 9, characterized in that the nozzle (82) is laterally flagable relative to the housing (28). A workhead (20) for a brushcutter, the workhead comprising: a housing (28); a cutting blade (42) supported by the housing (28); a gripping jaw (38) supported by the lower part of the housing (28), characterized by: the thumb (44) pivotally mounted on the housing (28) to pivot about a horizontal axis from a non-operative position, wherein the thumb (44) is at least substantially flush with the top of the housing (28) , towards the jaw (38) and thereby adhere to the cut bush and other debris between the thumb (44) and the housing (28); and an actuator (52) mounted inside the housing 15 (28) and coupled to the thumb (44) for pivoting the thumb (44) about said axis. 19 97939